Spirit Cat Of course, that map tells you more than „YOU ARE HERE“ - it puts your „here“ into relation to a set of known „there“s, just like your watch puts your „now“ into relation to a set of known „then“s.
Yay for idiofinders. (that's the name for them, thisn't me using ableist language, though the name might have been chosen due to ableism being normalised.)
I absolutely love the political stuff and I think it's super important to discuss and apply, but I'm glad that you're not solely focusing on the political philosophy.
Dnt Wry Those are precisely my feelings, as well. I'm a journalist in training and I need a thorough education in politics, socioeconomic, and ethics, but I would be hard pressed to say political, economic, and ethical philosophy are the only kinds I derive meaning, purpose, and pleasure from.
I love what Abigail does now but I do really enjoy this earlier, less on-the-pulse stuff. The world of today is so tumultuous and there seem to be new arguments of the moment or events that need to be properly analysed every day. Whilst properly framing a concept of the moment philosophically and contextually is good work and is what made Philosophy Tube really popular, and it must be difficult to NOT make something that is relevant to the world currently being on fire in many different ways, I do miss these more 'pure philosophy' investigative pieces.
Besides all the more scientific and philosophical definitions of time, most people seem to perceive time in relation to space. Time is described with spatial terms like "arrow of time", mostly linearly unlike what Einstein stated about it. In that way, it would seem time is so dependent on motion that we imagine "time stopping" as "space stopping" or the stopping of all motion. If that were the only way to perceive time then theoretically speaking, we can imagine a thought experiment where a universe had only two identical particles and they switch places with another at a certain rate and afterwards they trade locations at the same rate, then return to their original locations. If we observed this particle movement backwards or forwards we could not tell the difference between past and present as they look the same and moved the same unless we observed the original movement. Therefore perception of time as an abstract form of motion is erroneous. A common misconception of time. But we still rely on even with precise time-keeping devices like moving arms on a watch or changing digits on a clock.
"Time is an illusion. Lunchtime doubly so." Great video, and interesting to tackle a different philosophical topic that really comes back to one of the basic questions - how we perceive the world and what that means. Keep up the good work!
I don't see that the B-conceptualization makes relief impossible. You made a comparison to a book, and I can feel relief when I pass a climactic portion of a book, despite the text of the book remaining the same. "Thank goodness that's over" is easily reframable into "Thank goodness I'm past that", a statement that makes quite a bit of sense in terms of, for instance, a section of road that's under construction. To be fair, this requires a conceptualization of identity that allows a distinction between "I, now" and "I, then", but that seems pretty common afaict.
I find it weird that someone might subordinate metaphysical knowledge to human speech patterns. Why would the way humans speak have any influence over the properties of the universe?
It wouldn't, but it is an example of how the things we experience aren't necessarily accurate representations of how things really are. Other examples would be hallucinations and optical illusions. First-hand experience/testimony is one of the least reliable sources of information there are is all.
And yet, from a certain point of view, first-hand experience is ALL that exists, because to say that there is an objective reality is to make an assumption that is innately filtered through the subjective lens of the person making the assumption. Scientific experiments are supposed to be objective for instance, but they are being done by individuals who experience the experiment itself in a subjective manner. The only reason you can say that objective reality exists is by making a whole heap of assumptions you cannot actually prove. Of course, this is solipsism, which generally isn't well regarded. But the thing is, it's not a philosophy that is thought of poorly because it's wrong, but because it is on that list of things which can (presumably) never be proven, and thus invoking it means you shut down any possible argument. Plus, it's impractical. Science assumes objective reality exists, and the results appear to work. Whether that is actually true or not may well be irrelevant if the results remain consistent either way. (that is, if the shared, objective reality is in fact a delusion, it is one that is consistent enough that it may not matter one way or another if it's actually 'real')
I think it's gor more to do with the fact that us being able to considder a concept gives presidence for it's existance in some way. If something could happen in a causal world, it must happen (otherwise it couldn't have), so if we truly mean that something is possible, then it must also have happened. The alternative is that although only one thing can ever happen, we can imagine several outfalls based on different possibilites in the dark areas of our knowledge.
He isent claiming the universe works such and such way because we talk like this. He is using examples of how we talk to make the ideas of how the universe works easier to understand.
@@1a2b3c4d_ I see your point. I was attempting to be quirky, but I understand your perspective. I try not to continue being toxic in my masculinity, but I see I still have some work to do. My apologies, to you, Abigail, and any others that found the comment inappropriate.
I feel like the difference between A universes and B universes comes down basically to a change of reference frame. A theorists see themselves as standing still while time flows past them, while B theorists see time as standing still while they move through it - both are equally valid descriptions of the observation that there is relative motion between observers and time, just like the view that the train you‘re on is standing still and the landscape is moving past is just as valid as that of a train moving through a stationary landscape.
Unfortunately, the two positions are fundamentally different. If the disagreement was merely a matter of reference, then we would expect some similarities in descriptions of the matter of reference; however, A-theory, and B-theory describe entirely different things. The implications of the respective theories explicate mutually exclusive phenomenon that are competing for the descriptor "time". An analogy would be two people attempting to define "water", and one person is describing a rock while the other is describing water. Additionally, as an eternalist (a position within B-theory), I would argue that in B-theory that nothing is "flowing" through time anymore than time itself can be described as having some sort of active motion. Objects have temporal extension (they stretch over particular points in the time series), but nothing is in motion. An object (X) described at some instant in time (t) is not the entire object at t, rather, it is a temporal part of X (X') at t. So, the issue is that our language implies all of something that we speak of is presently located (Jake just fell on the ice), but we're actually referencing a part of the temporally extended object (a temporal part of Jake located at t1 fell on the ice). We describe temporal motion, because consciousness appears to only occupy one spacetime location, sequentially (we are never aware of our entire self). A-theory seems to imply that a person is spontaneously generated, ex nihilo, at "the" present instant. Read "The Ontolgy of Physical Objects...", by Mark Heller, for more about temporal parts.
"Thank goodness that's over" has the same problem as saying the sun "rises." We know it doesn't literally rise up around the edge of the Earth, but it's weird to try and put it otherwise.
TIMEQUAKE II BY KURT VONNEGUT is an underappreciated and silly bit of time fiction. (Essentially, the universe gets bored of expanding and decides to contract for a bit, causing everyone to live out their last few years in reverse.)
i've been seeing things in a b-universe way for a while now. i see time as a spatial dimension. and the reason it would be different than the other spatial dimensions is because everything is propelled in one direction (the direction of time) in it, unlike the 3 spatial dimensions which are just spaces that things hang out in or move lazily in. in my mind this explains evolution and our need to live. we have a force propelling us forward, we aren't just sitting here being alive. it also explains why passion can make you want to move mountains to realize your dreams. you are flowing more with the flow of time and life rather than against it.
I've been in the B-theory even before I knew the term, and I'm quite comfortable with it. Let me try to redefine the "stopping" of time in fashion that might make sense in B-theory: Although our physical selves are 4D objects with temporal parts, our conscience is only a 3D slice of that 4D object i.e. we do not (cannot) experience different temporal parts simultaneously. So "experience" is like a wave passing through the 4D object, experiencing each temporal slice in order. So to "experience" "stopping" of time, all that is needed is that for a time-length of our 4D object, the surrounding 4D objects to have the same 3D cross section and relative arrangement. All the effects described at the beginning of the video will be valid (inability to breathe/move), but in terms of 4D geometry it's conceivable.
Thanks for this video man. The comment section made me realize that I do really need to address all the little reasons why my theory makes more sense before I contend with the most difficult to explain ones that my current writings deal with exclusively
I really like your videos, but this one is the best one I'd seen. Your other videos are amazing, so saying this is my favorite is A LOT. I liked the way you combine physics and philosophy in a convincing way. The subject and the approach was brilliant. It made me think more deeply about time. I can't wait to do more research on it. THNAK YOU
Great video, I love me some metaphysics :D I have one problem though. Even if the pie is hot and cold and these properties exist simultaneously in 4d, we still experience this weird change of perspective that I can't really explain. I think it doesn't really matter if time actually passes or not, it's the fact that we experience these shifts in perspective which is interesting.
The last part reminded me of a Dylan Moran routine about how calling your lover's name during the act can take on different meanings wi th different tones.
If time was never moving then we'd have to be moving through time. In that case couldn't you say that "time stopping" has the same affect as "us not moving through time"?
Time traveler here. After the video Men. Abuse. Trauma the example with "I love you" gains a different meaning. The argument in 8:05 onwards is being made across several videos.
A different model (which I'm reasonably sure corresponds to relativity, despite the fact that I barely remember first year physics from uni) would be to keep the same definition of time but make the changes relative only to a single actor (the one moving about in the time that all changes between the other bodies are swapped). The person moving about in stopped time would still be able to move and find air and photons in the place they were at the start of the movement (as long as they didn't try in the exact same place twice, anyway).
Good stuff. If anyone wants to look into the other side of the argument (ie of course time flows, the passage of time is the most evident and fundamental thing we experience, but that doesn't mean the universe has to be presentist and Newtonian. Eternalist models of the universe that most people use simply lack the ability to describe it, but alternate models for the geometry of time can) I recommend looking up Tim Maudlin. His BigThink videos are interesting and cover a variety of topics in Philosophy of Science, but his debates and lectures concerning whether or not time has flow present an argument for a moving present within 4-dimensional spacetime.
My watch is staying on because there is a very good use for a paper that says “you are here” Because the function of a watch is to say “you are here” in the same way that, say, a wall map in a crowded mall says “you are here”; it tells me my location relative to everything else.
i refute that end bit about watches, in the B universe model its not a piece of paper saying you are here, its a gps constantly showing where in time you are, much more useful
Well, your watch would not be exactly a piece of paper saying "you are here", but a GPS that says "you are currently here". It tracks your movement through time in relation to other "positions".
Great video! I've always enjoyed your content and i hope your channel keeps evolving and improving. However, id like to point out a mistake that you've made. When speaking about heat as motion of particles we're referring to a very particular type of motion. Random motion. So moving as fast as the flash would not cause you to heat up as that would be uniform motion.
If I understand correctly, in the B scenario, a clock is not just like a paper that reads 'you are here ', but gives you coordinates relative to other temporal locations- similar to XY coordinates in two dimensional space coordinates.
Sorry for so many comments on one video, but this is my favorite kind of philosophy. So, for this argument, let's accept B-theory and the posit that the pie doesn't change in time, but that it is a discreet object in 3+1D spacetime. What about an acorn? First it was a part of a leaf and twig complex (which is part of a tree which is part of the planet, etc), then it fell and grew into a sprout, eventually it became a mighty oak, then it was felled, then it begins rotting, then its various parts are torn asunder and digested, then some bits go into the organism and are spent as energy (excreted as heat) while others are excreted into the soil. This soil becomes good earth for the next acorn. So, what is the discreet unit? I think, if we are going to accept this posit of B-theory, then we must look at all of spacetime as a discreet unit. While this may be true in the noumenal, it's not very useful in the phenomenological.
The concept of a B universe becomes kind of intuitive to me when I bare in mind that time is a dimension, the fourth dimention. Space is defined by three dimensions. A dimension is a line and lines are defined by infinite points that exist simultaneously one next to the other. Your watch is more than a paper saying "you are here", it's like a map with a gps. It tracks your location(temporal or spacial, respectively) in relation to other points. All the talk about change and the passing of time is grounded in our perception of what happens in these four dimensions. We understand the concept of dimension, the simultaneous existance of infinite points, when it comes to space, because we feal like everything just sits there. When it comes to time though, we percieve a more dynimic relation between two temporal locations, two points in time. I don't know how to explain that. I just understand that it is difficult to understand time the way we understand space because we cannot traverse within each of the four dimensions with the same ease.
We do that with space too. An infinite number of points still wouldn't get past the 0 point on any given axis since they have length/width/depth/time of 0. That's why B-Theorists tend to define objects through perdurance which describes the points between which all the matter is said to make up what that object is (in both space and time). But I see what you mean about viewing 3-D models as unmoving making temporal coordinates explain motion more intuitively. Presentists would say that 3-D space is all that's needed to provide movement, it's just not as useful when trying to _describe_ movement. Which is technically true if the past and future do not exist, but it gets more complex when you have to account for relativity. But that dynamic relationship between points in time is why I'm still an A-Theorist. I just believe in a 4-D spacetime which contains one or more instances of a moving present. That we can't traverse time with the same ease actually doesn't really enter into my thinking on the issue since in philosophy you can imagine whatever sort of time travel device you want so long as it's logically consistent. It's more the nature of consciousness that makes me feel like there's a moving present since I believe that the answer to the hard problem of consciousness is simply that it is born out of the flow of time and the activity of our brains processing information etc as opposed to simply the function of it. For example the functions of the brain are like the code of a computer game, but consciousness only arises when and while you're actually playing it (in other words only when it's responding to input as the input is entered). You could pre-program a set of instructions to replace the input, but nobody would call simulating the results of that the game being played. It would just be one long cutscene.
Sliding into the forum very late to say. "Thank goodness that's over" still works perfectly fine as a space-related sentence therefore should apply comfortably to a time-as-spacelike-experience. My thought was going over a speedbump in a car. WHUMP. "Thank goodness that's over". The speedbump is still there. It's right behind you and getting further away as you move. But you're still past it. You've moved on. And thus, as with time.
I visualize it like a book. There's a 2D character on the page, and as the pages turn, the character can exist in different places, it can cease to exist, it can change. If the pages stop, it just exists in that one temporal state until they start turning again. As the pages turn, the 2D character is constantly moving through the third dimension and instead of perceiving this the same way he perceives himself moving through 2D space, he perceives it as time.
time theory b reminds me of the alien's conception of time in slaughterhouse five. also, i am glad you covered this. when i watched cartoons as a kid time stopping powers were very puzzling to me.
Question: If we think about time like a "B" universe - what if it's not time that passes, but WE who pass time? Like the material world moves through time like a fish moves through water, and by so doing time leaves it's mark on us. Wouldn't that take care of the "A" Theorists problems with it? There are fish that can't stop swimming and there are organisms who can only move in one direction, not the other, so it might make sense that we can only move one way in time (forward). Has there been any philosophy on that idea or a similar one?
That would be an A-Theory model. There are issues with it if objects only exist in the present and don't exist in the future or past (ie relativity of simultaneity - see wikipedia article for elaboration) but there are also models like the moving spotlight theory where the 4-d spacetime universe exists just like in b-theory, but the present moves across it like a spotlight and only highlighted objects could be said to be currently in the present. This has issues with superfluousness though, and for some strange reason most moving spotlight theorists still insist on the present being simultaneous across the universe, which brings up the same problems with relativity. I'm working on a theory where there would actually be a physical reason for an object (meaning smallest possible objects individually) to be within an instance of the present, why it appears to be simultaneous when we only look at the actions of other nearby objects, and why it would actually be important to track, but few if any other A-Theorists (or B-Theorists for that matter) seem to think this is a possibility.
Would that really be A-Theory though? As the presentism variation implies only the present is real, and the growing-block theory supposes that only the past and present are real and the future isn't. The model I'm proposing argues they're all real (as in a B-Universe) but it's a passive-environment as opposed to an active force. Like if we think of it like we think of space, just because I'm in my apartment right now doesn't mean the summit of Katahdin doesn't exist. It's there - I'm just not. Also, semi-related but the Cruxshadows new song "Uncertainty (In Space and Time)" is kinda perfect for this discussion: ruclips.net/video/SK2CA0iXufE/видео.html
Yep, A-Theory only means that time has tense. So there is a past/present/future. What you describe there is the moving spotlight theory which is the one that I personally think is closest to being correct, but I don't feel has really been done well yet. The trouble its primary versions have is that there's no way to really differentiate between an object in the present and an object in the past/future. If the only difference is that one is currently labelled "in the present" then it's just arbitrary. If you can only tell that you are in the present because you are experiencing it, then Prosser argues that such an experience could not be caused or in any way affect the physical universe and therefore from a reductionist point of view cannot itself exist. I actually agree with him there, but I only think that that must mean that there is a physical reason for the present to be where it is and move at the rate it does, which is why I believe in a dynamic 4th dimension. My theory is more a hybrid between moving spotlight and growing block, but I find it easier to describe in terms of the former as I do believe that the future exists (just not necessarily in the same way that it will when we get around to experiencing it). (video at that link is either deleted or geo-gated)
Inside a black hole, theoretically, space and time change places, you can move around in time, but space flows relentlessly towards the singularity, like how time flows forward outside the black hole
B-Universe theory basically replaces change with locality, from what you describe. In that sense, a watch is less like a paper that says 'you are here' and more like the grid-lines on a map - each 'tick' of the clock is a grid line which we can use to help us 'locate' what bit of time a part of our experience occupies, compared to other bits, and make decisions about them. You don't need to look at a map to know you're 'here', but you might need to do so to know what 'here' means in relation to other locations you care about. It ultimately boils down to the fact that our language is very informal when talking about time and experiences. We use shorthand terms like 'that's over' or 'I'm looking forward to', because our perceptions are embedded in space and time just as our consciousness is. We can only experience those events located on one 'slice' of space-time at any given 'here'-moment, because the mechanisms for us to experience things require physical phenomena within space-time. So while the past and future exist independently of our experiences of them in a B-Universe, we are stuck unable to experience them directly, only make use of knowledge about the way events at one time seem to correlate to events at the next time - i.e., Memory. The Past/Future Memory issue seems like a challenge to B-Universe interpretations - if all of space-time exists, then why can we only remember the past and not the future? We seem to 'remember' the past by interpreting the current state of our 'Memory' as having arisen from interacting with events in past times. We seem to be unable to interpret our Memory to gather data about interactions with events in future times, which might be a problem for B-theory. My personal take on this problem runs something like this. Your memory is a thing that exists now, and bears certain markings. We, as beings who experience time in sequence, have become accustomed to instinctively relating the markings on our memory to events that happened in past times - i.e. to 'remember what happened'. This is an inexact process, fraught with errors. We also use our memory markings to relate to events in the future - i.e. 'to infer or predict what will happen'. This is also an inexact process, fraught with errors. In both cases, we can only *infer* what happened before, or will happen later, based on the Memory we have now, and that inference is of limited accuracy in both cases. We feel, intuitively, like our inference of the past is more accurate, but in reality we have just as little way or knowing with certainty what happened yesterday as we have of knowing what will happen tomorrow. Being limited, physical beings, dependent on perceptions of ourselves at a single moment in time to infer our pasts and our futures, is incredibly inconvenient from a philosophical perspective, but we have adapted well enough to i from a practical one.
It is the same logic behind it, if time is stationary strongly connected with space, there is no entropy, since in this 3d reality you cannot perceive how exactly time shifts to create our understanding of past, present and future in the same time/spot. The universe is just too complicated for our current minds, if there are more dimensions and time itself is like left, right, up, down, height, depth. We just know for a certain space-time is a thing, without it you cannot have heat, forces and matter interaction.
At first I thought he was arguing against B-theory, but later in the vid I realized that he was simply presenting it. An excellent presentation of this idea happens in the later half of 'Slaughterhouse Five', wherein time is viewed as a loaf of bread full of infinitesimally thin slices. The loaf never changes, it simply is, it is only the perspective that changes. So it goes, as they say.
If I understand B theory correctly, Kurt Vonnegut explained it very well in "Slaughterhouse-Five or The Children's Crusade: A Duty-Dance with Death" as how the Tralfama dorians, and most other species in the universe, percieve time.
The Story of You, the story Arrival is based on, deals with this. The aliens' concept of time, as communicated by learning their language, is not only non-linear, it's also simultaneous, which also means no free will. Arrival sorta steered just clear of that concept, probably because it's terrifying.
I was watching this at the kitchen table and my mom saw Olly on the screen over my shoulder and all she said was "That man looks like he's from the seventies."
I have an idea! We should put pictures from his videos into a collage to see how his hair has changed over time. idk but his long hair is so nice to look at.
I think a watch is a little more useful than that. It tells you "you are here" in time the same way GPS tells you "you are here" in space. It's a lot more precise than saying "you are here" and it tells you how to refer to that location when you stop being there.
I wish I could remember where I read this, but one interesting implication of B-series universe is when you add in quantum mechanics, not only do the "past" and "future" exist elsewhere on the time axis of our space-time cartesian coordinate field, but all possible futures and pasts and presents exist in a quantum superposition of each other, like a bit in a quantum computer but for all possible versions of the universe
That's close. Temporal cooridnates of other objects depend on various things including the distance we are from them so all quantum calculations have to be calculated relative to an object's point of view. Since quantum particles exist at every point in space, and space and time are relative, that does mean that at the quantum level the number of events which could technically be said to be seen by our quantum state would be vast. If you want to bring in the idea of all "possible" versions of the universe though you gotta accept String Theory (specifically the Many Worlds interpretation). That _might_ mean you heard it from Sean Carroll maybe? He's String Theory's champion in scientific pop culture.
This is a pretty fun starting point to lead into explaining the A and B theories of time which I hadn't thought about! I was pretty into time when I wrote about it for my metaphysics essay (unfortunately there wasn't a time travel module like at my brother's university though... ) but I've never managed to get much further than 'yeh I guess David Lewis sounds good enough idk'. You've just reminded me of how disappointed I was in myself that I didn't manage to fit in any of my Timesplitters: Future Perfect examples in my essay.... le sigh.... Anyway yeh good video (:
No Time Travel module? But that's what David Lewis' best work on time was all about! Don't think he called it this at the time but he essentially first posited the logical consistency of Circular Timelike Curves, but more importantly his description of why the Grandfather paradox would not happen in a deterministic universe but we would still have free will is the best explanation I've yet come across of how counterfactual logic really works. I only played the first Timesplitters. What examples did you have?
Ah yeh I did time travel in the last couple of weeks of metaphysics, so yeh definitely looked at Lewis' stuff about that! And oh no, my vague memories must be off, but I thought he said time loops (I had to google timelike curves but I think I'm talking about the same thing) wouldn't work either? Granted, I really can't remember what I thought Lewis' reasons for being against them even at the time so I'm probably wrong there. My main example was from Timesplitters Future Perfect, i.e TS3. In that game there were multiple points where the main character Cortez travels backwards in time through a wormhole to the same location, usually later interacting with his past self. The first time, the future Cortez appears above the present (i.e the player) Cortez, and drops him a key through a grille in future Cortez's floor. Present Cortez needs this key to get through a door and progress - which then leads him to go up a floor, go back in time, and then hand the *same* key down to a past Cortex underneath him. There are some strange issues with that maybe, like where did the key come from, and that in one intuitive sense we would think if it really is the same key then surely it would disintergrate at some point thanks to spending an eternity being used... But erm, I can't really remember what my point was going to be besides being like 'aren't causal loops funny?'
Yes his time loops were what later became known as Closed Timelike Curves. His conclusion was that they do not present any logical inconsistencies but he did still find them unlikely due to the whole chicken and egg problem of them having no causal beginning, but I'm pretty sure he still contended that if backwards time travel is possible every instance of it would take the form of such a loop in one way or another and his main argument was about how counterfactual logic preserves free will in such a loop where someone attempts to murder their younger self even though they would always fail in one way or another (because those instances cannot be the only possible worlds we consider when judging whether or not those failures can still be legitimately called coincidences). That Timesplitters scenario is a great example of a Bootstrap "Paradox". Physically it is a paradox but logically there doesn't need to be an origin of where the key came from. That's a good physical representation of why Lewis considered time loops logically consistent but unlikely due to the causal chain lacking a true beginning (though the causal chains alone would still be consistent with the physics whereas the bootstrap paradox would never happen). In an Eternalist A-Theory model where time flows time travel wouldn't entail CTCs, but they could still arise through an origin that started differently but ended up getting erased when the loop ended the reason for it, but almost nobody other than me takes such models seriously.
Good video. I'll be honest, I was so excited to comment that I glazed over some moments. To put my argument simply, a subject (i.e. a baby person) by its being subject does not change. I mean to convey a sense that (subjectively) time can be mutually independent of a subject.
PBS Space Time seems to largely argue for a B universe, a Block universe serendipitously. All time exists at once, there's no preferred arrow of time, we just happen to perceive it as moving forward due to events entangling themselves on us locally through imprinting on our brain. Before that event, we were still entangled, but only if you have perfect information about the entire universe.
I like the end of the video(and your other videos), but the physics in the start here are a bit generously formulated. The Planck time is the smallest measurable time, but that does not mean that the universe is discretized in Planck units, or something similar. It is just fundamental to quantum physics that any measurement of time has at least an uncertainty of the Planck time, because to get more accurate results you'd have to measure with less energy then the lowest possible energy, the Planck energy. Also, temperature is not necessarily a measure of the average speed. It is for a disordered system, but not necessarily for an ordered system. You could also argue that the observers would be very hot if you were to move fast, with your argument, as the laws of thermodynamics are invariant under relativity. Arguing that you are very hot because of some non-statistical effect would not be the best way of considering it. You really need the interaction with air around you in order for this to make sense, and that is just traditional air resistance. (I'm not entirely sure of the formulation of this, it's been quite a while since I have done statistical physics). Now some amateur philosophy response to the rest: I'm kind of interested if there is any real difference between an A-universe and a B-universe, because they only thing that seems to change is the formulation, not the meaning. I guess the B-universe formulation makes the most sense in physics, as there is no such thing as a purely time-based or space-based relation, as those are dependent on reference frames. You could argue that because spacelike and timelike distances are different, a A-universe formulation makes more sense. To me, either does not seem to have a particular different truth, just the words which would be used are different(which I guess could make our emotional connotation different, but that does not mean that . Basically, what I'm arguing for is that the difference between talking within the A-universe and within the B-universe is just a matter of talking in a different language. If you were to make a dictionary from one "language"(i.e. English in A-universe style) to the other "language"(i.e. English in a B-universe style), this would capture all the difference. There is no difference in meaning, only in the words(and the emotional connotation of them). I'm not sure of this though.
The "we need time to pass for sentences about change to make sense" arguments sort of ignore math, too: mathematicians can talk about a function "changing" but that just means you can find two outputs that aren't equal, functions (formally defined as sets of input-output pairs) don't "change" in a temporal sense. Time could be like that: (something like) ordinals paired with... intertial frames? Cosmic snapshots? Anyway then you can talk about objects "changing" without reference to time "passing."
An interesting idea about the possible nature of cosmological time (aside from it being part of the fabric of space according to Albert Einstein - and so effectively time stopping completely on a black hole's event horizon from the perspective of someone away from a black hole looking into it) is the idea that the events of the 'birth' and 'death' of the universe just depends on your perspective - i.e. they could be the same thing... not because of some linear property of the physical universe causing it to recycle anew when it dies, but due to the counter-intuitive effect of cosmological time causing death and re-birth of the universe to being at once in the distant past and distant future or death and re-birth being simultaneous... depending on your perspective in space-time. A simple example is on the event horizon of a black hole in-which all of time passes in an instant: and so, for a black hole formed at the beginning of the universe, time passes so quickly (eternity happens in an instant) that time effectively does not even occur - the beginning and end of the universe become simulteneous in this case... but that's black holes, and it's not couter-intuitive to understand once you understand how time and space warps using Einstein's laws. An even weirder example though - that is totally bizarre - is the effect of what happens On YOUR PERSPECTIVE OF TIME when you try to reach the edge of the observable universe... You'll never reach the edge of the universe for one thing as it is escaping from you, due to the exapnsion of the universe, at the speed of light - and you can't travel faster than the speed of light. But there is also other effects to consider... The expansion of the universe is accelerating, which means eventually even things relatively near to us in our own galaxy will, in the distant future, be moving away from us at the speed of light (or maybe even faster? - we don't know) - and this is thought to happen long before the universe dies (when all the stars have burned out, and even matter itself has decayed to sub-atomic particles)... Also, another thing to consider is that we always see the beginnings of the universe when we look at the edge of the observable universe - the moments just after the big bang.... So there you are racing towards the edge of the observable universe, which is always moving away from you... and the edge of the observable universe looks always as it did at the time of the big bang... If you now travelled faster than the speed of light to reach the edge of the observable - in order to beat the effect of the accelerating expansion of the universe contracting the observable distance you can see only to objects very near to you in your present time - you would start to travel forwards in time in respect of what you would be able to see of the edge of the observable universe... the universe at the edge of what is observable would start to age as you would see it - no longer appearing as it was 13.8 billion years ago, but appearing as it is nearer and nearer to the present to time... Now think about what that means... If your rate of acceleration met the contraction of the observable universe you could see due to the accelerating expansion of the universe - in effect the end of time... Then in the process of accelerating to the edge of the observable universe, the universe from your perspective aged from appearing as it was at the big bang (the beginning of time) to the present time of the end of the universe (the end of time)... ...But this is no different than if you stayed put in space and let the observable universe contract to sub-atomic distances due to the accelerating expansion of the universe... ...And as the big bang happened everywhere at once (the space you are in now) this really is the case... ...Plus, the fact that to go down to smaller and smaller scales, to the sub-atomic - like what scientists are doing at the Large Hadron Collider - you have to go back to conditions in the early universe that were present at the big bang... which are also in evident in black holes, which like I said before have time at their event horizons happening instantaneously.... ...So the Big Bang becomes the end of the universe at the same time! - but not because of something special you did like travelling faster than the speed of light to age the edge of the observable universe to how it is at the end of time from your perspective (like bringing the beginning of time towards you when you reach it at the end of time - as from your perspective) but because of the nature of cosmological time itself, which plays the same trick such that it isn't just a trick of a perspective of how you see time but how time actually is. (I really didn't cheat with this)
when i am playing playstation games the game sometimes appears to slow down as i become increasingly involved in it. Then i realise that the game is not slowing but the functioning of my brain is actually speeding up. I think that is what is happening here with you. Your brain is actually speeding up, so's to keep up with change. Great video anyhow.. Keep going.
Hmm, I very much liked this deeply intriguing video of yours, it makes sense. On another note, I don't blame you for confusing 'effect' with 'affect', it's a common mistake.
Time is an entropic anisometry in the configuration space of the universe. In other words, while most people assume that time is a strict linear progression from a single past through to a single future, it's actually more like a big ball of wibbly-wobbly... timey-wimey... stuff.
There is the theory of timeless physics suggested by Julian Barbour, that's similar to the idea of B-universes but maybe more extreme. If I understand correctly, in a B-universe there is no "now", no special pointer scanning over the time dimension - there is simply time, many moments existing in a continuum, which our minds perceive in slices we call "now". In timeless physics we just discard time completely - the point is that we don't really need time for the equations that describe the universe. We don't need this extra property stitched to the configuration of everything, we can describe everything without it (and it's even more elegant this way), so we Occam Razor it away. It's important to note this is far from being widely accepted, but it is accepted by some. BTW, regarding the criticism of A-universes, that sentences like "I'm glad that's over" don't make sense - well I don't really get it. Sure, from an objective overview of time, in some of it there is pain and in some there isn't. But since we as humans experience time in slices coming in an order, when the pain is "over" it means we can expect not to feel it again. In our subjective view of time as a directional linear progression, we won't have to go back to that period where there was pain. And that's good, so we're happy.
I could mention the 2nd law of thermodynamics (in-which the information content of the universe is always increasing - unless you consider the counterpart to black holes, called white holes, which reduce rather than increase entropy.. edit; though technically they increase the entropy of their surroundings.. it's complicated). Entropy of economics is an interesting topic - when you consider that we humans keep our entropy low by raising the entropy of our environment (in the form of heat).
Cool thoughts! But I think in the B-Universe you still need time to pass for your consciousness, or you'd be always looking to the same page of the book. You can't take a look at the next page without change. Your consciousness can't travel through the static time of the B-Universe unless time passes for it somehow. If change doesn't occur, you can only see either the hot part of the pie or its cool part, but not one after the other.
Part 3 was really good. We say the sun rises but it doesn't, the Earth is spinning. Similarly any phrases about time don't have to be consistent with the way time is. The argument against B-universes in part 2 didn't make sense to me for another reason. We already use changing words with respect to space, we say things like 'it gets hotter nearer the equator' or 'the river gets wider near the ocean' it doesn't 'get' hotter or wider it already is, just somewhere else. If time necessitates change because of our language then space does too, since we use similar words. It seems more likely from our language that time and space are similar, as posited by the B-universe.
I wrote my undergrad thesis on the philosophy of time, specifically updating Presentism and Eternalism in light of both relativity and quantum mechanics. My conclusion was ultimately that the two views had very few differences which had consequences for other areas of philosophy. It would lead to a difference in the ontolog of the past or the future, but no difference with free will or any of the other usual implications that are discussed. To give a really rough idea of how this implicates the debates you mentioned: the current state of an object, in a sufficiently detailed quantum level description, encodes within it the entire past of that object and all possible futures of that object. It doesn't guarantee any given future, but it does guarantee which futures are possible and how likely each one is. There are many ways to explain this, but Richard Feynmab did it best in his work on consistent histories, which was revolutionary in the development of a relativistic quantum field theory, the most accurate theory ever created by man according to scoentific testing. The idea is that every possible set of events that can happen does. More specifically, if you shine a beam of light at a mirror and reflect it off into a drtector, the light actually takes every path on the way. It splits into a superposition of every path it could take. Now all those patha going off at funny angles end up cancelling out and the paths that are closest to straight reinforce each other leading to an unimaginably high likelihood that the light will just go straight, hit the mirror, and bound off. But even if you very carefully remove bits of the mirror to change the way these paths cancel, you can show the effect. Even if you remove tue center of the mirror where it appears the light is hitting and instead only have very precisely measured mirror rings going around that hole, a portion of the light will actually still reflect, apparently off the hole, because of these effects. The implication is that if you have a sufficiently detailed explanation of anything, it got to be that way by every possible event that could have lead up to that precise quantum state having occurred, including all superpositions and descrete events. There is only 1 past in a macroscopic sense. Quantum superpositions collapse at that level. In the quantun level, where more than one path could have lead to where you are now, it is because those paths all ocurred and were in a superposition of possibilities. Similarly, although discrete events are probabilistic in quantum mechanics, the range of possibilities evolves deterministically. For any given current state, if we knew every knowable thing about them (and this does not implicate uncertainty, that's a different discussion) we could theoretically find the odds of each possible future event that would occur. So even if you believe that only the present momebt exists, you can still treat the past and future as proveable offshoots from your one point in spacetime. You can take them seriously because they are real implications encoded in the events of now.
Thanks for the comment. So in other words, if we revisit that moment in time by recreating every possible component and relation, then we can explore a different offshoot and thereby prove it? Doesn't the fact that the most complex component, the human observer, is changed by being older, more experienced, having gone thru that first moment already, doesn't this mean that the moment cannot be recreated faithfully? How are the offshoots provable?
Project Malus You can't put complex states back to that of an earlier time. You can do that with very simple quantum states with an experiment called the "quantum eraser." PBS spacetime has a good video explaining how it works. The interpretation of that experiment is highly controversial, but my favorite explanation is that by setting the relevant quantum state into an earlier state it essentially devolves it in time, sending it back in time and allowing the state to evolve again in the particle's future in accordance with the rules of quantum mechanics. Note though that the Quantum Eraser Experiment is right at the edge of my understanding. I can follow the explanations but it's hard to hold it in my head. I'm not 100% sure my explanation works.
Sam I'm sure I've seen that episode but for sure I'll watch it again :) I realized later that you probably meant time itself without the added complexity of an observer. Time by itself would be a fairly simple complex system with lots of the same components and basic relations with matter, quantitative in other words, and I could see how the quantum eraser could work. With the added complexity of a human in the mix, forget it! If you have time there's a paper by Vincent Vesterby "The intrinsic nature of emergence" I believe it's called, that shows how patterns that are created by matter particles moving in relation to one another are duplicated at higher levels of complexity. This was my thinking that the same "pattern" could be recreated and the moment revisited, but it just doesn't work with an observer since the relations are too complex.
I never sat down and read McTaggart's time theories, I'll get to them later (insert laughter here), but what I find unfortunate here is that I believe you are confusing Spacetime (clocktime) with Time. Now, I don't fully have a grasp of it myself, but basically what I'm getting at was at the center of probably the biggest debate in history, Henri Bergson vs. Albert Einstein on time. Henri Bergson being the man would blocked Albert Einstein from winning a Nobel Prize for his relativity theory because Bergson claimed Einstein's Theory was epistemological and not physics. So, when you say, you may want to throw out your watch at the end, you are confusing the two. Another way of expressing what I am trying to express, Time has been mistakenly expressed as extension. This is why we consider a clock to measure time; however, it does not measure time, it only measures the change in distance from, for example, noon to noon thirty. As Bergson states, "Ever since my university days I had been aware that duration is measured by the trajectory of a body in motion and that mathematical time is a line; but I had not yet observed that this operation contrasts radically with all other processes of measurement, for it is not carried out on an aspect or effect representative of what one wishes to measure, but on something which excludes it. The line one measures is immobile, time is mobility. The line is made, it is complete; time is what is happening, and more than that, it is what causes everything to happen. The measuring of time never deals with duration as duration; what is counted is only a certain number of extremities of intervals, or moments, in short, virtual halts in time... Tus it does nothing but lean in the direction of common sense, which is a beginning of science: usually when we speak of time we think of the measurement of duration, and not duration itself." (_The Creative Mind: An Introduction to Metaphysics_ by Henri Bergson Introduction I pg 12 and 13) So, I don't believe we can measure Time at all because Time is not extension in the sense of weight, distance, and change. "All through the history of philosophy time and space have been placed on the same level and treated as things of a kind; the procedure has been to study space, to determine its nature and function, and then to apply time to the conclusion thus reached." (Ibid page 14)
3:02 It certainly seems that time is global, but is that true? Spacetime is always relative to mass-energy. If _C_ (the speed of causality, light, and gravity to name the most obvious) is constant, than that is a global rule and we should be measuring other things against it. Regarding things moving quickly (and therefore experiencing more time) effecting their surroundings, light, moving at light speed, doesn't heat up the medium orthogonal to it's direction of movement. It only has an outside effect when crashing into something (as far as I know).
"Thank goodness that's over" is itself an indexical phrase. It may be true for the "present" you but it doesn't have to be true for the "past" you. Relativity doesn't mean ambiguity it simply acknowledges the truth of seemingly conflicting statements.
Surely the B-theory's temporal equivalent of a piece of paper that says "you are here" is a piece of paper that says "you are now". A watch is more like a 1-dimensional GPS, but for time instead of space (except the GPS info would be relative to some point on the surface of the earth, while the watch is it's own reference frame)?
There is a Zen poem that, translated to English, goes as follows: "I am on a bridge, and O marvel! It is not the river which flows, it is the bridge which moves over the torrent."
What about entropy? That concept (a measure of the state of (dis)order) didn't exist in the time of Aristotle, but entropy and the second law of thermodynamics clearly define a sequential pattern in the state of the universe (and all the objects in it). Since entropy tends to increase, time tends to pass globally (you can decrease entropy locally but only through increasing it elsewhere; there's also an astonishingly incredibly small -but non-zero - chance that entropy will spontaneously decrease so I guess time would go backwards there but that's so small that it practically never happens).
I, for one, am extremely appreciative of standing maps that have a "YOU ARE HERE" marker on them, so I'll be holding onto my watch for now.
Spirit Cat Of course, that map tells you more than „YOU ARE HERE“ - it puts your „here“ into relation to a set of known „there“s, just like your watch puts your „now“ into relation to a set of known „then“s.
Yay for idiofinders. (that's the name for them, thisn't me using ableist language, though the name might have been chosen due to ableism being normalised.)
I absolutely love the political stuff and I think it's super important to discuss and apply, but I'm glad that you're not solely focusing on the political philosophy.
The political philosophy is my primary area, but it's nice to take a break from it and think about other things. I'd be miserable otherwise.
Dnt Wry
Those are precisely my feelings, as well. I'm a journalist in training and I need a thorough education in politics, socioeconomic, and ethics, but I would be hard pressed to say political, economic, and ethical philosophy are the only kinds I derive meaning, purpose, and pleasure from.
Yeah, me too - I wanted to get a few more diverse ones out there before I start my 4-part big series on liberalism which'll be coming up in two weeks!
Will liberalism have Stirner in it?
Please, put Max Stirner in it. He really didn't like liberalism.
Nice spooks :P
I love what Abigail does now but I do really enjoy this earlier, less on-the-pulse stuff. The world of today is so tumultuous and there seem to be new arguments of the moment or events that need to be properly analysed every day. Whilst properly framing a concept of the moment philosophically and contextually is good work and is what made Philosophy Tube really popular, and it must be difficult to NOT make something that is relevant to the world currently being on fire in many different ways, I do miss these more 'pure philosophy' investigative pieces.
sort of how like VSauce does his videos
*ZA WARUDO*
Fucking beat me to it!
TOMAREEE TOKI WOOOO
JoJo's has the most inconsistent time stop
I confirm that Jojo fans are EVERY FUCKING WHERE
@@yonatanbeer3475 How is it inconsistent?
Besides all the more scientific and philosophical definitions of time, most people seem to perceive time in relation to space. Time is described with spatial terms like "arrow of time", mostly linearly unlike what Einstein stated about it. In that way, it would seem time is so dependent on motion that we imagine "time stopping" as "space stopping" or the stopping of all motion. If that were the only way to perceive time then theoretically speaking, we can imagine a thought experiment where a universe had only two identical particles and they switch places with another at a certain rate and afterwards they trade locations at the same rate, then return to their original locations. If we observed this particle movement backwards or forwards we could not tell the difference between past and present as they look the same and moved the same unless we observed the original movement. Therefore perception of time as an abstract form of motion is erroneous. A common misconception of time. But we still rely on even with precise time-keeping devices like moving arms on a watch or changing digits on a clock.
"Time is an illusion. Lunchtime doubly so."
Great video, and interesting to tackle a different philosophical topic that really comes back to one of the basic questions - how we perceive the world and what that means. Keep up the good work!
I don't see that the B-conceptualization makes relief impossible. You made a comparison to a book, and I can feel relief when I pass a climactic portion of a book, despite the text of the book remaining the same. "Thank goodness that's over" is easily reframable into "Thank goodness I'm past that", a statement that makes quite a bit of sense in terms of, for instance, a section of road that's under construction.
To be fair, this requires a conceptualization of identity that allows a distinction between "I, now" and "I, then", but that seems pretty common afaict.
I find it weird that someone might subordinate metaphysical knowledge to human speech patterns. Why would the way humans speak have any influence over the properties of the universe?
It wouldn't, but it is an example of how the things we experience aren't necessarily accurate representations of how things really are. Other examples would be hallucinations and optical illusions. First-hand experience/testimony is one of the least reliable sources of information there are is all.
And yet, from a certain point of view, first-hand experience is ALL that exists, because to say that there is an objective reality is to make an assumption that is innately filtered through the subjective lens of the person making the assumption.
Scientific experiments are supposed to be objective for instance, but they are being done by individuals who experience the experiment itself in a subjective manner.
The only reason you can say that objective reality exists is by making a whole heap of assumptions you cannot actually prove.
Of course, this is solipsism, which generally isn't well regarded.
But the thing is, it's not a philosophy that is thought of poorly because it's wrong, but because it is on that list of things which can (presumably) never be proven, and thus invoking it means you shut down any possible argument.
Plus, it's impractical.
Science assumes objective reality exists, and the results appear to work. Whether that is actually true or not may well be irrelevant if the results remain consistent either way. (that is, if the shared, objective reality is in fact a delusion, it is one that is consistent enough that it may not matter one way or another if it's actually 'real')
Of course human speech has influence over the properties of the universe or how would magic spells work JK
I think it's gor more to do with the fact that us being able to considder a concept gives presidence for it's existance in some way. If something could happen in a causal world, it must happen (otherwise it couldn't have), so if we truly mean that something is possible, then it must also have happened. The alternative is that although only one thing can ever happen, we can imagine several outfalls based on different possibilites in the dark areas of our knowledge.
He isent claiming the universe works such and such way because we talk like this. He is using examples of how we talk to make the ideas of how the universe works easier to understand.
Slaughterhouse Five by Kurt Vonnegut does a great job of describing b-universe time.
Is there a Patreon level where I can have Abigail send me “I love you” texts every two minutes for a week?
That’s kind of creepy
@@1a2b3c4d_ just a bit, but hey, para-social relationships are badass 😎
@@nowlun oke
@@1a2b3c4d_ I see your point. I was attempting to be quirky, but I understand your perspective. I try not to continue being toxic in my masculinity, but I see I still have some work to do. My apologies, to you, Abigail, and any others that found the comment inappropriate.
I read this before I got to that part and thought that was just something you came up with as an appealing scenario lol
This is my FAVORITE EPISODE EVER! These are my fav conversations to have with my husband and friends.
I'm in Simon Prosser's class at St. Andrews right now, and my exam is tomorrow. Thanks for the revision help.
Michael Sansbury Jr. out of curiosity, how’d ya do?
fredreick weaver Can’t remember, don’t think it did badly though
I feel like the difference between A universes and B universes comes down basically to a change of reference frame. A theorists see themselves as standing still while time flows past them, while B theorists see time as standing still while they move through it - both are equally valid descriptions of the observation that there is relative motion between observers and time, just like the view that the train you‘re on is standing still and the landscape is moving past is just as valid as that of a train moving through a stationary landscape.
Unfortunately, the two positions are fundamentally different. If the disagreement was merely a matter of reference, then we would expect some similarities in descriptions of the matter of reference; however, A-theory, and B-theory describe entirely different things. The implications of the respective theories explicate mutually exclusive phenomenon that are competing for the descriptor "time". An analogy would be two people attempting to define "water", and one person is describing a rock while the other is describing water. Additionally, as an eternalist (a position within B-theory), I would argue that in B-theory that nothing is "flowing" through time anymore than time itself can be described as having some sort of active motion. Objects have temporal extension (they stretch over particular points in the time series), but nothing is in motion. An object (X) described at some instant in time (t) is not the entire object at t, rather, it is a temporal part of X (X') at t. So, the issue is that our language implies all of something that we speak of is presently located (Jake just fell on the ice), but we're actually referencing a part of the temporally extended object (a temporal part of Jake located at t1 fell on the ice). We describe temporal motion, because consciousness appears to only occupy one spacetime location, sequentially (we are never aware of our entire self). A-theory seems to imply that a person is spontaneously generated, ex nihilo, at "the" present instant. Read "The Ontolgy of Physical Objects...", by Mark Heller, for more about temporal parts.
"Thank goodness that's over" has the same problem as saying the sun "rises." We know it doesn't literally rise up around the edge of the Earth, but it's weird to try and put it otherwise.
TIMEQUAKE II BY KURT VONNEGUT is an underappreciated and silly bit of time fiction. (Essentially, the universe gets bored of expanding and decides to contract for a bit, causing everyone to live out their last few years in reverse.)
'We are here and this is now' Terry Pratchett
i've been seeing things in a b-universe way for a while now. i see time as a spatial dimension. and the reason it would be different than the other spatial dimensions is because everything is propelled in one direction (the direction of time) in it, unlike the 3 spatial dimensions which are just spaces that things hang out in or move lazily in.
in my mind this explains evolution and our need to live. we have a force propelling us forward, we aren't just sitting here being alive.
it also explains why passion can make you want to move mountains to realize your dreams. you are flowing more with the flow of time and life rather than against it.
I've been in the B-theory even before I knew the term, and I'm quite comfortable with it. Let me try to redefine the "stopping" of time in fashion that might make sense in B-theory: Although our physical selves are 4D objects with temporal parts, our conscience is only a 3D slice of that 4D object i.e. we do not (cannot) experience different temporal parts simultaneously. So "experience" is like a wave passing through the 4D object, experiencing each temporal slice in order. So to "experience" "stopping" of time, all that is needed is that for a time-length of our 4D object, the surrounding 4D objects to have the same 3D cross section and relative arrangement. All the effects described at the beginning of the video will be valid (inability to breathe/move), but in terms of 4D geometry it's conceivable.
"Thank goodness that experience is located at a time prior to the indexicly defined present"
that sounds so scifi, i love it
Thanks for this video man. The comment section made me realize that I do really need to address all the little reasons why my theory makes more sense before I contend with the most difficult to explain ones that my current writings deal with exclusively
I really like your videos, but this one is the best one I'd seen. Your other videos are amazing, so saying this is my favorite is A LOT. I liked the way you combine physics and philosophy in a convincing way. The subject and the approach was brilliant. It made me think more deeply about time. I can't wait to do more research on it. THNAK YOU
i dont know why but the ,,wherever you are ,, part really gave me the chills
Great video, I love me some metaphysics :D I have one problem though. Even if the pie is hot and cold and these properties exist simultaneously in 4d, we still experience this weird change of perspective that I can't really explain. I think it doesn't really matter if time actually passes or not, it's the fact that we experience these shifts in perspective which is interesting.
You inspired me to add a philosophy minor to my acting major. Thank you, you're amazing
That's amazing! Congrats!
It’s really interesting seeing these videos as a new fan. Love this stuff and I’m excited for more of her in the future
Very Very. Indeed.
I ain't gonna throw out my watch, what would I throw out my map? I find value in knowing where I am.
The last part reminded me of a Dylan Moran routine about how calling your lover's name during the act can take on different meanings wi th different tones.
If time was never moving then we'd have to be moving through time. In that case couldn't you say that "time stopping" has the same affect as "us not moving through time"?
Exactly what I thought. This way, the concept of "time as the fourth dimention" makes much more sense to me.
Been binge watching her vids. They are so good. I feel smart lol
Time traveler here. After the video Men. Abuse. Trauma the example with "I love you" gains a different meaning. The argument in 8:05 onwards is being made across several videos.
Another time traveler here. Abby is actually a woman
A different model (which I'm reasonably sure corresponds to relativity, despite the fact that I barely remember first year physics from uni) would be to keep the same definition of time but make the changes relative only to a single actor (the one moving about in the time that all changes between the other bodies are swapped). The person moving about in stopped time would still be able to move and find air and photons in the place they were at the start of the movement (as long as they didn't try in the exact same place twice, anyway).
Good stuff. If anyone wants to look into the other side of the argument (ie of course time flows, the passage of time is the most evident and fundamental thing we experience, but that doesn't mean the universe has to be presentist and Newtonian. Eternalist models of the universe that most people use simply lack the ability to describe it, but alternate models for the geometry of time can) I recommend looking up Tim Maudlin. His BigThink videos are interesting and cover a variety of topics in Philosophy of Science, but his debates and lectures concerning whether or not time has flow present an argument for a moving present within 4-dimensional spacetime.
My watch is staying on because there is a very good use for a paper that says “you are here”
Because the function of a watch is to say “you are here” in the same way that, say, a wall map in a crowded mall says “you are here”; it tells me my location relative to everything else.
As someone with an avid interest in time, I quite enjoyed this.
This. This episode! When I have money I'm going to join your patreon. OMG I loved this episode! THANK YOU!
i refute that end bit about watches, in the B universe model its not a piece of paper saying you are here, its a gps constantly showing where in time you are, much more useful
ZA WARUDO, TOKI WO TOMARE!
Well, your watch would not be exactly a piece of paper saying "you are here", but a GPS that says "you are currently here". It tracks your movement through time in relation to other "positions".
Great video! I've always enjoyed your content and i hope your channel keeps evolving and improving. However, id like to point out a mistake that you've made. When speaking about heat as motion of particles we're referring to a very particular type of motion. Random motion. So moving as fast as the flash would not cause you to heat up as that would be uniform motion.
If I understand correctly, in the B scenario, a clock is not just like a paper that reads 'you are here ', but gives you coordinates relative to other temporal locations- similar to XY coordinates in two dimensional space coordinates.
Time absolutely does speed up and slow down. That was the biggest revolutionary idea in relativity.
As a person who, due to ADHD is literally time blind, I have no idea what I just watched. I live my life without time, and I always have.
Sorry for so many comments on one video, but this is my favorite kind of philosophy.
So, for this argument, let's accept B-theory and the posit that the pie doesn't change in time, but that it is a discreet object in 3+1D spacetime. What about an acorn? First it was a part of a leaf and twig complex (which is part of a tree which is part of the planet, etc), then it fell and grew into a sprout, eventually it became a mighty oak, then it was felled, then it begins rotting, then its various parts are torn asunder and digested, then some bits go into the organism and are spent as energy (excreted as heat) while others are excreted into the soil. This soil becomes good earth for the next acorn. So, what is the discreet unit?
I think, if we are going to accept this posit of B-theory, then we must look at all of spacetime as a discreet unit. While this may be true in the noumenal, it's not very useful in the phenomenological.
Thank you sir u r my favorite youtuber now
The concept of a B universe becomes kind of intuitive to me when I bare in mind that time is a dimension, the fourth dimention. Space is defined by three dimensions. A dimension is a line and lines are defined by infinite points that exist simultaneously one next to the other. Your watch is more than a paper saying "you are here", it's like a map with a gps. It tracks your location(temporal or spacial, respectively) in relation to other points. All the talk about change and the passing of time is grounded in our perception of what happens in these four dimensions. We understand the concept of dimension, the simultaneous existance of infinite points, when it comes to space, because we feal like everything just sits there. When it comes to time though, we percieve a more dynimic relation between two temporal locations, two points in time. I don't know how to explain that. I just understand that it is difficult to understand time the way we understand space because we cannot traverse within each of the four dimensions with the same ease.
We do that with space too. An infinite number of points still wouldn't get past the 0 point on any given axis since they have length/width/depth/time of 0. That's why B-Theorists tend to define objects through perdurance which describes the points between which all the matter is said to make up what that object is (in both space and time). But I see what you mean about viewing 3-D models as unmoving making temporal coordinates explain motion more intuitively. Presentists would say that 3-D space is all that's needed to provide movement, it's just not as useful when trying to _describe_ movement. Which is technically true if the past and future do not exist, but it gets more complex when you have to account for relativity.
But that dynamic relationship between points in time is why I'm still an A-Theorist. I just believe in a 4-D spacetime which contains one or more instances of a moving present. That we can't traverse time with the same ease actually doesn't really enter into my thinking on the issue since in philosophy you can imagine whatever sort of time travel device you want so long as it's logically consistent. It's more the nature of consciousness that makes me feel like there's a moving present since I believe that the answer to the hard problem of consciousness is simply that it is born out of the flow of time and the activity of our brains processing information etc as opposed to simply the function of it. For example the functions of the brain are like the code of a computer game, but consciousness only arises when and while you're actually playing it (in other words only when it's responding to input as the input is entered). You could pre-program a set of instructions to replace the input, but nobody would call simulating the results of that the game being played. It would just be one long cutscene.
Sliding into the forum very late to say. "Thank goodness that's over" still works perfectly fine as a space-related sentence therefore should apply comfortably to a time-as-spacelike-experience. My thought was going over a speedbump in a car. WHUMP. "Thank goodness that's over". The speedbump is still there. It's right behind you and getting further away as you move. But you're still past it. You've moved on. And thus, as with time.
I visualize it like a book. There's a 2D character on the page, and as the pages turn, the character can exist in different places, it can cease to exist, it can change. If the pages stop, it just exists in that one temporal state until they start turning again. As the pages turn, the 2D character is constantly moving through the third dimension and instead of perceiving this the same way he perceives himself moving through 2D space, he perceives it as time.
time theory b reminds me of the alien's conception of time in slaughterhouse five. also, i am glad you covered this. when i watched cartoons as a kid time stopping powers were very puzzling to me.
And one year later, re-watching this video did the same affect towards my brain; it made my brain hurts!
Question: If we think about time like a "B" universe - what if it's not time that passes, but WE who pass time? Like the material world moves through time like a fish moves through water, and by so doing time leaves it's mark on us. Wouldn't that take care of the "A" Theorists problems with it?
There are fish that can't stop swimming and there are organisms who can only move in one direction, not the other, so it might make sense that we can only move one way in time (forward).
Has there been any philosophy on that idea or a similar one?
That would be an A-Theory model. There are issues with it if objects only exist in the present and don't exist in the future or past (ie relativity of simultaneity - see wikipedia article for elaboration) but there are also models like the moving spotlight theory where the 4-d spacetime universe exists just like in b-theory, but the present moves across it like a spotlight and only highlighted objects could be said to be currently in the present. This has issues with superfluousness though, and for some strange reason most moving spotlight theorists still insist on the present being simultaneous across the universe, which brings up the same problems with relativity.
I'm working on a theory where there would actually be a physical reason for an object (meaning smallest possible objects individually) to be within an instance of the present, why it appears to be simultaneous when we only look at the actions of other nearby objects, and why it would actually be important to track, but few if any other A-Theorists (or B-Theorists for that matter) seem to think this is a possibility.
Would that really be A-Theory though? As the presentism variation implies only the present is real, and the growing-block theory supposes that only the past and present are real and the future isn't.
The model I'm proposing argues they're all real (as in a B-Universe) but it's a passive-environment as opposed to an active force. Like if we think of it like we think of space, just because I'm in my apartment right now doesn't mean the summit of Katahdin doesn't exist. It's there - I'm just not.
Also, semi-related but the Cruxshadows new song "Uncertainty (In Space and Time)" is kinda perfect for this discussion:
ruclips.net/video/SK2CA0iXufE/видео.html
Yep, A-Theory only means that time has tense. So there is a past/present/future. What you describe there is the moving spotlight theory which is the one that I personally think is closest to being correct, but I don't feel has really been done well yet. The trouble its primary versions have is that there's no way to really differentiate between an object in the present and an object in the past/future. If the only difference is that one is currently labelled "in the present" then it's just arbitrary. If you can only tell that you are in the present because you are experiencing it, then Prosser argues that such an experience could not be caused or in any way affect the physical universe and therefore from a reductionist point of view cannot itself exist.
I actually agree with him there, but I only think that that must mean that there is a physical reason for the present to be where it is and move at the rate it does, which is why I believe in a dynamic 4th dimension. My theory is more a hybrid between moving spotlight and growing block, but I find it easier to describe in terms of the former as I do believe that the future exists (just not necessarily in the same way that it will when we get around to experiencing it).
(video at that link is either deleted or geo-gated)
Inside a black hole, theoretically, space and time change places, you can move around in time, but space flows relentlessly towards the singularity, like how time flows forward outside the black hole
B-Universe theory basically replaces change with locality, from what you describe. In that sense, a watch is less like a paper that says 'you are here' and more like the grid-lines on a map - each 'tick' of the clock is a grid line which we can use to help us 'locate' what bit of time a part of our experience occupies, compared to other bits, and make decisions about them. You don't need to look at a map to know you're 'here', but you might need to do so to know what 'here' means in relation to other locations you care about.
It ultimately boils down to the fact that our language is very informal when talking about time and experiences. We use shorthand terms like 'that's over' or 'I'm looking forward to', because our perceptions are embedded in space and time just as our consciousness is. We can only experience those events located on one 'slice' of space-time at any given 'here'-moment, because the mechanisms for us to experience things require physical phenomena within space-time. So while the past and future exist independently of our experiences of them in a B-Universe, we are stuck unable to experience them directly, only make use of knowledge about the way events at one time seem to correlate to events at the next time - i.e., Memory.
The Past/Future Memory issue seems like a challenge to B-Universe interpretations - if all of space-time exists, then why can we only remember the past and not the future? We seem to 'remember' the past by interpreting the current state of our 'Memory' as having arisen from interacting with events in past times. We seem to be unable to interpret our Memory to gather data about interactions with events in future times, which might be a problem for B-theory.
My personal take on this problem runs something like this. Your memory is a thing that exists now, and bears certain markings. We, as beings who experience time in sequence, have become accustomed to instinctively relating the markings on our memory to events that happened in past times - i.e. to 'remember what happened'. This is an inexact process, fraught with errors. We also use our memory markings to relate to events in the future - i.e. 'to infer or predict what will happen'. This is also an inexact process, fraught with errors. In both cases, we can only *infer* what happened before, or will happen later, based on the Memory we have now, and that inference is of limited accuracy in both cases. We feel, intuitively, like our inference of the past is more accurate, but in reality we have just as little way or knowing with certainty what happened yesterday as we have of knowing what will happen tomorrow.
Being limited, physical beings, dependent on perceptions of ourselves at a single moment in time to infer our pasts and our futures, is incredibly inconvenient from a philosophical perspective, but we have adapted well enough to i from a practical one.
And what about the "arrow of time" and entropy flow eh? There is a lot of important points to the subject being omitted.
It is the same logic behind it, if time is stationary strongly connected with space, there is no entropy, since in this 3d reality you cannot perceive how exactly time shifts to create our understanding of past, present and future in the same time/spot. The universe is just too complicated for our current minds, if there are more dimensions and time itself is like left, right, up, down, height, depth. We just know for a certain space-time is a thing, without it you cannot have heat, forces and matter interaction.
Ooh, loved this one, it really engaged ideas from my linguistics degree of deixis!
*he mentioned Rick and Morty, he MUST be a philosophy major*
At first I thought he was arguing against B-theory, but later in the vid I realized that he was simply presenting it.
An excellent presentation of this idea happens in the later half of 'Slaughterhouse Five', wherein time is viewed as a loaf of bread full of infinitesimally thin slices. The loaf never changes, it simply is, it is only the perspective that changes. So it goes, as they say.
Time is just a category we have in order to better be able to perceive processes
If I understand B theory correctly, Kurt Vonnegut explained it very well in "Slaughterhouse-Five or The Children's Crusade: A Duty-Dance with Death" as how the Tralfama
dorians, and most other species in the universe, percieve time.
The Story of You, the story Arrival is based on, deals with this. The aliens' concept of time, as communicated by learning their language, is not only non-linear, it's also simultaneous, which also means no free will. Arrival sorta steered just clear of that concept, probably because it's terrifying.
I was watching this at the kitchen table and my mom saw Olly on the screen over my shoulder and all she said was "That man looks like he's from the seventies."
I really hope to see more videos on metaphysics.
this is my first video and I have to say how glad I am that I discovered your channel :)
Awesome! Welcome to the little community!
I have an idea! We should put pictures from his videos into a collage to see how his hair has changed over time. idk but his long hair is so nice to look at.
too lazy
I think a watch is a little more useful than that. It tells you "you are here" in time the same way GPS tells you "you are here" in space. It's a lot more precise than saying "you are here" and it tells you how to refer to that location when you stop being there.
I wish I could remember where I read this, but one interesting implication of B-series universe is when you add in quantum mechanics, not only do the "past" and "future" exist elsewhere on the time axis of our space-time cartesian coordinate field, but all possible futures and pasts and presents exist in a quantum superposition of each other, like a bit in a quantum computer but for all possible versions of the universe
That's close. Temporal cooridnates of other objects depend on various things including the distance we are from them so all quantum calculations have to be calculated relative to an object's point of view. Since quantum particles exist at every point in space, and space and time are relative, that does mean that at the quantum level the number of events which could technically be said to be seen by our quantum state would be vast. If you want to bring in the idea of all "possible" versions of the universe though you gotta accept String Theory (specifically the Many Worlds interpretation). That _might_ mean you heard it from Sean Carroll maybe? He's String Theory's champion in scientific pop culture.
You are literally the most amazing person
No, I am fairly certain watches are more useful than that. I've owned one before and it seemed to me quite helpful.
your voice tone is so good
you should broadcast at radio station
Thanks!
This is a pretty fun starting point to lead into explaining the A and B theories of time which I hadn't thought about! I was pretty into time when I wrote about it for my metaphysics essay (unfortunately there wasn't a time travel module like at my brother's university though... ) but I've never managed to get much further than 'yeh I guess David Lewis sounds good enough idk'. You've just reminded me of how disappointed I was in myself that I didn't manage to fit in any of my Timesplitters: Future Perfect examples in my essay.... le sigh.... Anyway yeh good video (:
No Time Travel module? But that's what David Lewis' best work on time was all about! Don't think he called it this at the time but he essentially first posited the logical consistency of Circular Timelike Curves, but more importantly his description of why the Grandfather paradox would not happen in a deterministic universe but we would still have free will is the best explanation I've yet come across of how counterfactual logic really works.
I only played the first Timesplitters. What examples did you have?
Ah yeh I did time travel in the last couple of weeks of metaphysics, so yeh definitely looked at Lewis' stuff about that! And oh no, my vague memories must be off, but I thought he said time loops (I had to google timelike curves but I think I'm talking about the same thing) wouldn't work either? Granted, I really can't remember what I thought Lewis' reasons for being against them even at the time so I'm probably wrong there.
My main example was from Timesplitters Future Perfect, i.e TS3. In that game there were multiple points where the main character Cortez travels backwards in time through a wormhole to the same location, usually later interacting with his past self. The first time, the future Cortez appears above the present (i.e the player) Cortez, and drops him a key through a grille in future Cortez's floor. Present Cortez needs this key to get through a door and progress - which then leads him to go up a floor, go back in time, and then hand the *same* key down to a past Cortex underneath him. There are some strange issues with that maybe, like where did the key come from, and that in one intuitive sense we would think if it really is the same key then surely it would disintergrate at some point thanks to spending an eternity being used... But erm, I can't really remember what my point was going to be besides being like 'aren't causal loops funny?'
Yes his time loops were what later became known as Closed Timelike Curves. His conclusion was that they do not present any logical inconsistencies but he did still find them unlikely due to the whole chicken and egg problem of them having no causal beginning, but I'm pretty sure he still contended that if backwards time travel is possible every instance of it would take the form of such a loop in one way or another and his main argument was about how counterfactual logic preserves free will in such a loop where someone attempts to murder their younger self even though they would always fail in one way or another (because those instances cannot be the only possible worlds we consider when judging whether or not those failures can still be legitimately called coincidences).
That Timesplitters scenario is a great example of a Bootstrap "Paradox". Physically it is a paradox but logically there doesn't need to be an origin of where the key came from. That's a good physical representation of why Lewis considered time loops logically consistent but unlikely due to the causal chain lacking a true beginning (though the causal chains alone would still be consistent with the physics whereas the bootstrap paradox would never happen). In an Eternalist A-Theory model where time flows time travel wouldn't entail CTCs, but they could still arise through an origin that started differently but ended up getting erased when the loop ended the reason for it, but almost nobody other than me takes such models seriously.
Right, cool, thanks for explaining all that, and much more fluently :) I'm gonna try and reread all of this again one of these days.
Amazing video as always!
Good video. I'll be honest, I was so excited to comment that I glazed over some moments.
To put my argument simply, a subject (i.e. a baby person) by its being subject does not change. I mean to convey a sense that (subjectively) time can be mutually independent of a subject.
PBS Space Time seems to largely argue for a B universe, a Block universe serendipitously. All time exists at once, there's no preferred arrow of time, we just happen to perceive it as moving forward due to events entangling themselves on us locally through imprinting on our brain. Before that event, we were still entangled, but only if you have perfect information about the entire universe.
I like the end of the video(and your other videos), but the physics in the start here are a bit generously formulated. The Planck time is the smallest measurable time, but that does not mean that the universe is discretized in Planck units, or something similar. It is just fundamental to quantum physics that any measurement of time has at least an uncertainty of the Planck time, because to get more accurate results you'd have to measure with less energy then the lowest possible energy, the Planck energy.
Also, temperature is not necessarily a measure of the average speed. It is for a disordered system, but not necessarily for an ordered system. You could also argue that the observers would be very hot if you were to move fast, with your argument, as the laws of thermodynamics are invariant under relativity. Arguing that you are very hot because of some non-statistical effect would not be the best way of considering it. You really need the interaction with air around you in order for this to make sense, and that is just traditional air resistance. (I'm not entirely sure of the formulation of this, it's been quite a while since I have done statistical physics).
Now some amateur philosophy response to the rest:
I'm kind of interested if there is any real difference between an A-universe and a B-universe, because they only thing that seems to change is the formulation, not the meaning. I guess the B-universe formulation makes the most sense in physics, as there is no such thing as a purely time-based or space-based relation, as those are dependent on reference frames. You could argue that because spacelike and timelike distances are different, a A-universe formulation makes more sense. To me, either does not seem to have a particular different truth, just the words which would be used are different(which I guess could make our emotional connotation different, but that does not mean that .
Basically, what I'm arguing for is that the difference between talking within the A-universe and within the B-universe is just a matter of talking in a different language. If you were to make a dictionary from one "language"(i.e. English in A-universe style) to the other "language"(i.e. English in a B-universe style), this would capture all the difference. There is no difference in meaning, only in the words(and the emotional connotation of them). I'm not sure of this though.
The "we need time to pass for sentences about change to make sense" arguments sort of ignore math, too: mathematicians can talk about a function "changing" but that just means you can find two outputs that aren't equal, functions (formally defined as sets of input-output pairs) don't "change" in a temporal sense. Time could be like that: (something like) ordinals paired with... intertial frames? Cosmic snapshots? Anyway then you can talk about objects "changing" without reference to time "passing."
An interesting idea about the possible nature of cosmological time (aside from it being part of the fabric of space according to Albert Einstein - and so effectively time stopping completely on a black hole's event horizon from the perspective of someone away from a black hole looking into it) is the idea that the events of the 'birth' and 'death' of the universe just depends on your perspective - i.e. they could be the same thing... not because of some linear property of the physical universe causing it to recycle anew when it dies, but due to the counter-intuitive effect of cosmological time causing death and re-birth of the universe to being at once in the distant past and distant future or death and re-birth being simultaneous... depending on your perspective in space-time.
A simple example is on the event horizon of a black hole in-which all of time passes in an instant: and so, for a black hole formed at the beginning of the universe, time passes so quickly (eternity happens in an instant) that time effectively does not even occur - the beginning and end of the universe become simulteneous in this case... but that's black holes, and it's not couter-intuitive to understand once you understand how time and space warps using Einstein's laws.
An even weirder example though - that is totally bizarre - is the effect of what happens On YOUR PERSPECTIVE OF TIME when you try to reach the edge of the observable universe...
You'll never reach the edge of the universe for one thing as it is escaping from you, due to the exapnsion of the universe, at the speed of light - and you can't travel faster than the speed of light.
But there is also other effects to consider... The expansion of the universe is accelerating, which means eventually even things relatively near to us in our own galaxy will, in the distant future, be moving away from us at the speed of light (or maybe even faster? - we don't know) - and this is thought to happen long before the universe dies (when all the stars have burned out, and even matter itself has decayed to sub-atomic particles)...
Also, another thing to consider is that we always see the beginnings of the universe when we look at the edge of the observable universe - the moments just after the big bang....
So there you are racing towards the edge of the observable universe, which is always moving away from you... and the edge of the observable universe looks always as it did at the time of the big bang... If you now travelled faster than the speed of light to reach the edge of the observable - in order to beat the effect of the accelerating expansion of the universe contracting the observable distance you can see only to objects very near to you in your present time - you would start to travel forwards in time in respect of what you would be able to see of the edge of the observable universe... the universe at the edge of what is observable would start to age as you would see it - no longer appearing as it was 13.8 billion years ago, but appearing as it is nearer and nearer to the present to time...
Now think about what that means...
If your rate of acceleration met the contraction of the observable universe you could see due to the accelerating expansion of the universe - in effect the end of time... Then in the process of accelerating to the edge of the observable universe, the universe from your perspective aged from appearing as it was at the big bang (the beginning of time) to the present time of the end of the universe (the end of time)...
...But this is no different than if you stayed put in space and let the observable universe contract to sub-atomic distances due to the accelerating expansion of the universe...
...And as the big bang happened everywhere at once (the space you are in now) this really is the case...
...Plus, the fact that to go down to smaller and smaller scales, to the sub-atomic - like what scientists are doing at the Large Hadron Collider - you have to go back to conditions in the early universe that were present at the big bang... which are also in evident in black holes, which like I said before have time at their event horizons happening instantaneously....
...So the Big Bang becomes the end of the universe at the same time! - but not because of something special you did like travelling faster than the speed of light to age the edge of the observable universe to how it is at the end of time from your perspective (like bringing the beginning of time towards you when you reach it at the end of time - as from your perspective) but because of the nature of cosmological time itself, which plays the same trick such that it isn't just a trick of a perspective of how you see time but how time actually is. (I really didn't cheat with this)
when i am playing playstation games the game sometimes appears to slow down as i become increasingly involved in it. Then i realise that the game is not slowing but the functioning of my brain is actually speeding up.
I think that is what is happening here with you. Your brain is actually speeding up, so's to keep up with change.
Great video anyhow.. Keep going.
That footage of left side driving made me really anxious
Hmm, I very much liked this deeply intriguing video of yours, it makes sense. On another note, I don't blame you for confusing 'effect' with 'affect', it's a common mistake.
Time is an entropic anisometry in the configuration space of the universe.
In other words, while most people assume that time is a strict linear progression from a single past through to a single future, it's actually more like a big ball of wibbly-wobbly... timey-wimey... stuff.
There is the theory of timeless physics suggested by Julian Barbour, that's similar to the idea of B-universes but maybe more extreme. If I understand correctly, in a B-universe there is no "now", no special pointer scanning over the time dimension - there is simply time, many moments existing in a continuum, which our minds perceive in slices we call "now". In timeless physics we just discard time completely - the point is that we don't really need time for the equations that describe the universe. We don't need this extra property stitched to the configuration of everything, we can describe everything without it (and it's even more elegant this way), so we Occam Razor it away. It's important to note this is far from being widely accepted, but it is accepted by some.
BTW, regarding the criticism of A-universes, that sentences like "I'm glad that's over" don't make sense - well I don't really get it. Sure, from an objective overview of time, in some of it there is pain and in some there isn't. But since we as humans experience time in slices coming in an order, when the pain is "over" it means we can expect not to feel it again. In our subjective view of time as a directional linear progression, we won't have to go back to that period where there was pain. And that's good, so we're happy.
8:31 speak for yourself, Olly!
In that sense, watch is rather a navigator, that shows where am I in time
I could mention the 2nd law of thermodynamics (in-which the information content of the universe is always increasing - unless you consider the counterpart to black holes, called white holes, which reduce rather than increase entropy.. edit; though technically they increase the entropy of their surroundings.. it's complicated). Entropy of economics is an interesting topic - when you consider that we humans keep our entropy low by raising the entropy of our environment (in the form of heat).
Cool thoughts! But I think in the B-Universe you still need time to pass for your consciousness, or you'd be always looking to the same page of the book. You can't take a look at the next page without change. Your consciousness can't travel through the static time of the B-Universe unless time passes for it somehow. If change doesn't occur, you can only see either the hot part of the pie or its cool part, but not one after the other.
Part 3 was really good. We say the sun rises but it doesn't, the Earth is spinning. Similarly any phrases about time don't have to be consistent with the way time is. The argument against B-universes in part 2 didn't make sense to me for another reason. We already use changing words with respect to space, we say things like 'it gets hotter nearer the equator' or 'the river gets wider near the ocean' it doesn't 'get' hotter or wider it already is, just somewhere else. If time necessitates change because of our language then space does too, since we use similar words. It seems more likely from our language that time and space are similar, as posited by the B-universe.
Zach Morris was my first introduction to stopping time.
I put this on my "Watch Later" list.
Hopefully one day, I'll get thru it all.
I wonder if those that reject determinism and are also more likely to reject the idea of B series time.
I wrote my undergrad thesis on the philosophy of time, specifically updating Presentism and Eternalism in light of both relativity and quantum mechanics. My conclusion was ultimately that the two views had very few differences which had consequences for other areas of philosophy. It would lead to a difference in the ontolog of the past or the future, but no difference with free will or any of the other usual implications that are discussed.
To give a really rough idea of how this implicates the debates you mentioned: the current state of an object, in a sufficiently detailed quantum level description, encodes within it the entire past of that object and all possible futures of that object. It doesn't guarantee any given future, but it does guarantee which futures are possible and how likely each one is.
There are many ways to explain this, but Richard Feynmab did it best in his work on consistent histories, which was revolutionary in the development of a relativistic quantum field theory, the most accurate theory ever created by man according to scoentific testing. The idea is that every possible set of events that can happen does. More specifically, if you shine a beam of light at a mirror and reflect it off into a drtector, the light actually takes every path on the way. It splits into a superposition of every path it could take. Now all those patha going off at funny angles end up cancelling out and the paths that are closest to straight reinforce each other leading to an unimaginably high likelihood that the light will just go straight, hit the mirror, and bound off. But even if you very carefully remove bits of the mirror to change the way these paths cancel, you can show the effect. Even if you remove tue center of the mirror where it appears the light is hitting and instead only have very precisely measured mirror rings going around that hole, a portion of the light will actually still reflect, apparently off the hole, because of these effects.
The implication is that if you have a sufficiently detailed explanation of anything, it got to be that way by every possible event that could have lead up to that precise quantum state having occurred, including all superpositions and descrete events. There is only 1 past in a macroscopic sense. Quantum superpositions collapse at that level. In the quantun level, where more than one path could have lead to where you are now, it is because those paths all ocurred and were in a superposition of possibilities.
Similarly, although discrete events are probabilistic in quantum mechanics, the range of possibilities evolves deterministically. For any given current state, if we knew every knowable thing about them (and this does not implicate uncertainty, that's a different discussion) we could theoretically find the odds of each possible future event that would occur.
So even if you believe that only the present momebt exists, you can still treat the past and future as proveable offshoots from your one point in spacetime. You can take them seriously because they are real implications encoded in the events of now.
Thanks for the comment. So in other words, if we revisit that moment in time by recreating every possible component and relation, then we can explore a different offshoot and thereby prove it? Doesn't the fact that the most complex component, the human observer, is changed by being older, more experienced, having gone thru that first moment already, doesn't this mean that the moment cannot be recreated faithfully? How are the offshoots provable?
Project Malus You can't put complex states back to that of an earlier time. You can do that with very simple quantum states with an experiment called the "quantum eraser." PBS spacetime has a good video explaining how it works. The interpretation of that experiment is highly controversial, but my favorite explanation is that by setting the relevant quantum state into an earlier state it essentially devolves it in time, sending it back in time and allowing the state to evolve again in the particle's future in accordance with the rules of quantum mechanics.
Note though that the Quantum Eraser Experiment is right at the edge of my understanding. I can follow the explanations but it's hard to hold it in my head. I'm not 100% sure my explanation works.
Sam I'm sure I've seen that episode but for sure I'll watch it again :)
I realized later that you probably meant time itself without the added complexity of an observer. Time by itself would be a fairly simple complex system with lots of the same components and basic relations with matter, quantitative in other words, and I could see how the quantum eraser could work. With the added complexity of a human in the mix, forget it!
If you have time there's a paper by Vincent Vesterby "The intrinsic nature of emergence" I believe it's called, that shows how patterns that are created by matter particles moving in relation to one another are duplicated at higher levels of complexity. This was my thinking that the same "pattern" could be recreated and the moment revisited, but it just doesn't work with an observer since the relations are too complex.
People interested should also read "The Order of Time" by Carlo Rovelli. He basically expands and recontextualizes the B-theory.
I never sat down and read McTaggart's time theories, I'll get to them later (insert laughter here), but what I find unfortunate here is that I believe you are confusing Spacetime (clocktime) with Time. Now, I don't fully have a grasp of it myself, but basically what I'm getting at was at the center of probably the biggest debate in history, Henri Bergson vs. Albert Einstein on time. Henri Bergson being the man would blocked Albert Einstein from winning a Nobel Prize for his relativity theory because Bergson claimed Einstein's Theory was epistemological and not physics. So, when you say, you may want to throw out your watch at the end, you are confusing the two. Another way of expressing what I am trying to express, Time has been mistakenly expressed as extension. This is why we consider a clock to measure time; however, it does not measure time, it only measures the change in distance from, for example, noon to noon thirty. As Bergson states,
"Ever since my university days I had been aware that duration is measured by the trajectory of a body in motion and that mathematical time is a line; but I had not yet observed that this operation contrasts radically with all other processes of measurement, for it is not carried out on an aspect or effect representative of what one wishes to measure, but on something which excludes it. The line one measures is immobile, time is mobility. The line is made, it is complete; time is what is happening, and more than that, it is what causes everything to happen. The measuring of time never deals with duration as duration; what is counted is only a certain number of extremities of intervals, or moments, in short, virtual halts in time... Tus it does nothing but lean in the direction of common sense, which is a beginning of science: usually when we speak of time we think of the measurement of duration, and not duration itself."
(_The Creative Mind: An Introduction to Metaphysics_ by Henri Bergson Introduction I pg 12 and 13)
So, I don't believe we can measure Time at all because Time is not extension in the sense of weight, distance, and change.
"All through the history of philosophy time and space have been placed on the same level and treated as things of a kind; the procedure has been to study space, to determine its nature and function, and then to apply time to the conclusion thus reached." (Ibid page 14)
3:02 It certainly seems that time is global, but is that true? Spacetime is always relative to mass-energy. If _C_ (the speed of causality, light, and gravity to name the most obvious) is constant, than that is a global rule and we should be measuring other things against it.
Regarding things moving quickly (and therefore experiencing more time) effecting their surroundings, light, moving at light speed, doesn't heat up the medium orthogonal to it's direction of movement. It only has an outside effect when crashing into something (as far as I know).
"Thank goodness that's over" is itself an indexical phrase. It may be true for the "present" you but it doesn't have to be true for the "past" you. Relativity doesn't mean ambiguity it simply acknowledges the truth of seemingly conflicting statements.
oooooh didn't think about the being cold part
Surely the B-theory's temporal equivalent of a piece of paper that says "you are here" is a piece of paper that says "you are now". A watch is more like a 1-dimensional GPS, but for time instead of space (except the GPS info would be relative to some point on the surface of the earth, while the watch is it's own reference frame)?
There is a Zen poem that, translated to English, goes as follows: "I am on a bridge, and O marvel! It is not the river which flows, it is the bridge which moves over the torrent."
Does this mean Shrek is a B-Theorist? Because, as we all know, it's never ogre.
here's a reminder you made this comment lol
What about entropy? That concept (a measure of the state of (dis)order) didn't exist in the time of Aristotle, but entropy and the second law of thermodynamics clearly define a sequential pattern in the state of the universe (and all the objects in it). Since entropy tends to increase, time tends to pass globally (you can decrease entropy locally but only through increasing it elsewhere; there's also an astonishingly incredibly small -but non-zero - chance that entropy will spontaneously decrease so I guess time would go backwards there but that's so small that it practically never happens).
I love you, Olly.
interesting recommendation given current events