Why Do You Remember The Past But Not The Future?
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- Опубликовано: 8 сен 2024
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The laws of physics don’t specify an arrow of time - they don’t distinguish the past from the future. The equations we use to describe how things evolve forward in time also perfectly describe their evolution backwards in time. So the brain is a thing ruled by the laws of physics - why does the brain and the conscious experience that emerges from it, see the arrow of time so clearly? In other words why do we remember the past and not the future?
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I really love clicking on these videos and thinking I’m going to understand. Gets me every time.
You do understand at the basic level but lack the scientific vocabulary
...these vids only hint at mathematical probabilities that obscure our complete understanding of reality...still sharing the thrill of discovery is exciting, makes for great conversations too!
@@scrumshies Bingo
God has said in the Quran; " And they urge you to hasten the punishment. But Allah will never fail in His promise. And indeed, a day with your Lord is like a thousand years of those which you count." (Quran, surah 22; ayat 47)
You might have understood this one if he didn't go off on a massive tangent and start talking about rocks. I had to shut the video off shortly after that because it really was an unnecessary tangent. The question of why don't we remember the future ought to be one that can be answered in a relatively succinct way, and his chap failed miserably.
I have to watch these multiple times over the course of years. But eventually I understand
"lets imagine the brain as a perfect sphere"
yes. completely smooth
completely
So you on Ifunny huh musta blew in from stupid town
@@emote5653 i live in the US
you're not far off
assuming a spherical brain in a vacuum...
😂
Thank you Matt. I am 76 YO and a disabled combat veteran. Life could get very boring. But with your very fine program I have much to think about and life is interesting again!
Thank you for your service.
These videos are always great food for thought
Thank you for your service, and I really hope I’ll either get to help solve or just witness the solving of the grand unified theory in my life. Or at least see in what ways quantum physics and general relativity are tied together. But what really has me excited is all this new information that the James Webb has been providing us with lately!!🎉😄
yooooo
This message must be the most wholesome on the internet
Perfect timing! I was thinking about this a couple days from now!
🤔
That is not grammatically correct. In using a past tense version of "to be," you are committing your thought to the past. That means you can write, "I was thinking about this a couple days ago," but you cannot logically write, "I was thinking about this a couple days from now." Regardless of the physics involved, the language used forces your thought to arise in the past tense, the present tense, or the future tense but without combinations (past tense verb leading to a future tense outcome).
@@michaelerickson985 I know that it is grammatically incorrect. I was playing on the fact that people in youtube comment sections always say "I was just thinking about that" or something like that. The humor comes from the fact that the joke starts off with someone thinking its the common comment, but then switches to something related to the video, defying expectation. Unless you're joking too and I just got trolled ecksdee
You remembered the future, that's why.
Shi funny dawg🤭
“Brains aren’t rocks, despite similarities in some cases”
And I took that personally
Some* cases
@@darookmezd give the rock a break
Rock on!
Well, considering we're teaching rocks to think for us the distinction between rocks and brains is definitely blurring.
Martian geo-inteligences take exception to this statement.
.... Well they will once they have had another few million years to perceive that the claim is being made.
I love how this implies that the universe as a whole does “know” its own future, at least in a classical model.
Agreed, if the universe encompases all matter then it will also encompase the whole environment in which matter can interact and should therefore remember both the past and the present, the question is if there are other universes out there or if the expansion of space is inlcuded in this universe or if its an interaction occuring from a fourth dimension, then the universe wont know its future
“The future has already happened, it just hasn’t happened yet.”
Actually, all possible futures has already happened, is happening, and will happen.
it's called fate
It happens only when we think it has - oh wait, then it’s the past. All that happens really is now. Or, now. Wait, now. How about now? Are you good? I think I’ll choose blueberry pancakes, wait, maybe strawberry ones - wish I could see my future to know what I will choose!
I like it when someone posts a cool quote, and it's subsequently followed by dumbshit comments.
@@P4INKiller it WAS a cool quote! It still is! And I like it too!
Me: **minding my own business**
PBS Space Time: "Would you like us to educate you into an existential crisis?"
Oh man, if you like existential crises, you would really enjoy exurb1a.
Man also add some prehistoric future sauce
every single episode lately tbh
I like the feeling of dread and angst
@@LeoStaley I am subscribed to that man. I've been seeing his videos in my feed for years now. They always sound so innocuous. Yet I know they will inevitably make me sad. So they lie there, in my subscription tab, unclicked, always...
If you play this video in reverse, you'll remember the future.
Smart
But you'll remember the past as well, which would mean that both the future and the past would be... the past?
You watching the video, that was produced in the past, is not going to allow you to see the future.... but it was a great way to keep us on our toes. 😉
or just play it twice
😂
1:32 Matt's memory is so good he even remembers when he was Gabe!
Hahah, I made that exact same remark. I could flatter us both by saying something cheesy like "great minds think alike", but realy... It just proves that there are no original thoughs... ;)
@@EvenTheDogAgrees Great minds think alike, but dull ones rarely differ.
Gabe is an impostor
It's wonderful that the energy put into creating his heat death t-shirt contributed to the acceleration of heat death itself.
Chanting Heat Death!
The invocation ritual that works!
His physics related t-shirt obeys the laws of physics too?!!! Whaaaat.
The Big Bang evolved from a state of heat death already. So there is no real heat death. It's a phase transition.
@@pcuimac Interesting angle.
That's one of those thoughts that can keep me awake an night.
I'll try not to let it.
The energy involved would have contributed regardless of purpose.
Hope that makes you feel better.
"Time's fun when you're having flies"
-Kermit Trismegistus The Frog
"Obviously our brains aren't rocks, despite the similarity in some cases..." when I'm watching Space Time, my brain is usually a rock.
I’m usually stoned as well.
And even then my brain is still pretty stupid, even for a rock
Well.....stoned is a perceptual shift , an excuse for being high when you are high already. High means expanded in the truest sense o me llia... Nothingness wrote this response...
This is so much easier than reading textbooks, doing homework, taking tests and working in groups.
Learning is not a spectator sport
He - forget the rock let's go simpler (starts explaining quantum physics)
Me - I'm good with rock
Sometimes the physics gets so advanced it feels like philosophy
“Why we remember the past but not the future?”
Actually, this video toes the lines of Laplace's demon which is a philosophical idea. I actually had an easier time understanding the physics of this because of that particular philosophical idea
So true!
@@thewanderingsouldooob9867 oo.. I am researching that right away.. thanks for sharing!🍄🌈
Aristotle was essentially a theoretical physicist, particularly with his Uncaused Cause explanation of the beginning of time or reality; he gave many physical phenomenon a scientific appraisal notable for his time... though he is most often referred to as a _philosopher_
I believe he coined the word "physics." He even wrote the METAphysics... meta just means after, as it was literally a collection of his works collected and published _after_ his writings in _Physics_
Philosophy wants to understand as much about the experience of being as physics does about the natural non-self world
Perhaps they are just that, philosophers guessing.
There are way more examples of so called smart people convincing themselves that their pet hypothesis was correct than there are people actually being correct.
Perhaps its as simple as we can't remember the future because it hasn't happened yet.
As a researcher who studies asteroid geology, I appreciate the custom-tailored metaphor.
Intriguing, where do you conduct your research? And are you personally worried about an asteroid hitting our planet?
Thats data packets of intelligence. Im not worried.
@@AlxM96 probably not worried about asteroid hitting, but more on studying the geochemistry of asteroid, with special concerns on finding ice (constitute of water, building blocks of life) or iron (hinting asteroid as being once a core of a planet)
As a future geologist, that's amazing
@@MikeDG00 I do know that's his profession and my question has pretty much nothing to do with it, it was merely a curiosity of mine :)
I can remember the future, but I usually only remember that I can remember the future when I am having intense and vivid deja vu in the present
Thank you for your comment !! Helped me understand the "deja vu" !!
The title should be “do rocks remember the future”
I'm not so sure about all this past/future remembering. For instance: I don't remember a word of what you just said, but I remember clearly how confused I felt right after the next episode, which is still in the future.
That's because watching an episode of SpaceTime doesn't add any new correlations (knowledge) to your brain and you already have the correlation between SpaceTime and utter confusion.
@@sabrinusglaucomys Jokes aside, that's a very accurate description of my relation with SpaceTime. Well done, Sir.
I do remember the future. I'm just preoccupied with understanding the past at this present moment.
Right now, we are as old as we have ever been, and as young as we'll ever be.
Sup God
twisting my melon man
This comments deserves more likes
i like that not heard that before !
no we've been younger -_-
I am actually surprised, this is one of the few episodes that I seem to mostly understand/get. Thought provoking stuff in this one!
1:33 Our past will clearly always be correlated with Gabe. Love the little call-backs every once in a while.
This is probably the best thought experiment to watch after watching Tenet.
Thanks for posting my future comment in the past
@@amanforalltheseasons You have a future in the past!
God has said in the Quran; " And they urge you to hasten the punishment. But Allah will never fail in His promise. And indeed, a day with your Lord is like a thousand years of those which you count." (Quran, surah 22; ayat 47)
Is it on Netflix ?
I also remembered Tenet when he talked about the reversed asteroid
10:40 I love how Dr. O'Dowd sneaks a joke in while holding a straight face during the lesson.
My question: how do we humans know if we experience time "forward" or "backwards?" If we pass "backward," how would we know? It seems to be that no matter what direction time is going, we will always perceive it as going "forward."
That's an interesting idea. If we could remember the future instead of the past, would it still seem like what you could remember is the future, or would we be forced to consider that the past and vice versa? Ultimately, I think the answer is in the video: we can't remember the future because of locality. The information about future events is spread out among many (possibly causally disconnected) objects in their positions, velocities, and other states. It is only once they converge at the present that the information becomes locally imprinted on your state, enabling you to remember it. If you try to run it backwards, the state of the object is correlated with things outside its light cone, so causality would be broken.
It doesn't matter, forward and backward aren't relative
@@bradleybaker976 Thanks for this comment, fits to my question. Is entropy relative?
Neither. It's not time that's in motion, it's objects.
“forward” and “backward” are just arbitrary labels. What is ‘forward’ to one person could be ‘backwards’ to another, hence, they are not objective metrics. The better question to ask is, “why do I remember one temporal direction and not both?”
Watching these gives me the creepy and exciting feeling that we are sneaking up to the edge of realizing something huge about ourselves and the universe. The building blocks are coming together, but we haven't looked at the whole thing yet.
I guess our knowledge is correlating.
Think of the whole of existence as oceans within oceans. We have the ocean as we know it as water, but then is the atmosphere itself not an ocean? Is the Earth not spinning along within an ocean of electromagnetism, and gravity? There are simply other oceans as well. Time is an illusion due to the construction of the matter we're composed of. The future already exists. Just the same as the past does. It's already there. In all of the multitudes of the various forms it makes.
Same. It almost feels like we are unraveling a primordial scroll containing the secrets of reality itself.
And it has this feeling at least for me that we've known it already. And I guess by "we" I refer to the collective "consciousness" of being. It feels like we're rediscovering something. Weird.
I just know that if I had the brains to understand the content, this would be my favourite RUclips channel, by a distance.
"We'll think of the brain as a rock."
And a CPU is just a rock beaten into the right shape with lightning put in it, go on...
"Clever Thunderstorm Flesh That Thinks"
@@tomisntblue oh no... kanji
Dwayne, the rock.
And a brain is just a coal beaten into the right shape with sunlight and the slow fire of metabolism, go on...
I think a CPU is more akin to a 'laws of physics'. It governs conditionality, but it has only very short term memory (anything long term is pushed to RAM or to disk). If you feed it certain data, the output will codify certain information about that data, which you can then use in further meta-conditionalities. But what CPU architecture provides is really the laws behind those conditionalities.
Last night I watched the movie Mr. Nobody for the first time. In the movie there is the line "why do we remember the past but not the future?" Right after hearing that line I had to pause the movie to digest what that meant, unpaused it a couple minutes later and finished the movie. Today I get this recommended and now I'm kinda freakin out.
you have now entered the twilight zone 💪😁
When watching this I remembered an interview with Roger Penrose in which he talked about his idea that in the far future of the universe, distance might become meaningless and so the universe will "forget" it's size and basically reset to a super dense state and "big bang" again. I do not recall the mechanism he proposed for this. But if entanglement increases over the lifetime of the universe and more more particles get entangled and if information between entangled particles is transmitted instantaneously, would that not also mean that distance becomes meaningless?
“Information” doesn’t “transfer” between particles instantaneously, as information cannot travel faster than light.
@@demetergrasseater It seems like it does, actually.
I think what might be a possible explanation is that the scale of things changes. So if you are let's say scale size 1 right now. Then things spread out to scale size 50. In the future you could possibly be remade except you are now spread out over scale size 100. The original scale size 1 becomes meaningless because scale size 100 is now the new scale size 1. The universe forgot the original scale size 1 and has now started to build things at the new scale.
*vsauce pops up*
And did the past ACTUALLY happen?
Perfect.
No, the past does not exist
The past already happen. Or IS IT?
How can I be real if the mirror isn't
Now let's replace that asteroid with a brain, a Boltzmann Brain...
So I Can worry about it endlessly when trying to sleep
@M C wise words
If you want to see the ideas and concepts explored in this video presented in the dramatic form, then watch the truly phenomenal German Netflix show, "Dark." Nothing that I've ever seen treats time the way that show does and it is beautifully written, acted, directed, shot....it's definitely one of their best shows, especially if you're into subjects like this.
I have tried watching "Dark" on Netflix because I love shows about time...however I find that show somewhat confusing...my son watched it and he kinda got it...but not all the way. He really could not explain it to me. I stopped watching because I found it somewhat scarier...Idk why
...He would always ask if I were going to watch it again...and would tell him No and that it was to creepy. Deep down I would like to start the show over ..but for some reason I can't bring myself to do so and idk why.
@@skyluvstar It's worth it, trust me
YESSS!!! Dark changed my entire thought process and expansion of questioning thoughts 💫💯
Dark is a good series but absolutely pseudoscience!
Acting is kinda bruh ok
"A time traveler."
"Knock-knock."
"Who's there?"
Lol good one!
Well, it looks like the time traveller is inverted. But still good one:)
What an unlikely scenario!
So the time traveler is just saying "a time traveler" to a closed door?
*K G B*
PBS Space Time: As unlikely as decreasing entropy
The Protagonist entered the chat.
So the cream rises to the top and says something.
There is no decreasing entropy. Entropy dis not grow either. A white hole on the back side of a black hole guarantees this stability.
tenet
@@peregrineweal not quite.
Imagine our "now" is a 3D "slice" of a 4D object which is us during our lifetime
Now, each slice's "now" can only remember what's inscribed in memory
The question is then, why should we experience each slice in the order that we experience it in?
And the answer is maybe that that's the most rational way to experience it, since each slice builds upon the previous one
Or does our brain only identifies the slice in order but we randomly experience the slices
I love this! You should coin "the slice theory" ☺️🙌🤘
I love the joke about the brain and how as a physicist you’ll start with making the assumption it is a perfectly round sphere lol
I remember the future. It just happened tomorrow.
happened
@@I.disagree I did not get your message.... but you can tell you what reality is and how the universe was created...
When will then be now?
Close. You remembere(d) the future...(has already) happened...(and that definitions of yesterday, today, or) tomorrow (are arbitrary descriptions made from different observers contrasting frames of reference). But nicely tensed pun 💁🏻♂️
@@MAN_FROM_BEYOND ...or then.
one time i had a dream and a few days later that moment happened exactly as i had seen it. never been able to have another experience like that but its something i always remember
Same!
Deja vú?
Had it many times. Very concerning moments.
YOU TIME TRAVELED AND BACK
Probably a coincidence.
There are some bizarre coincidences in this life and world.
I don't remember the future, but i often see it coming.
I remember the future... It's gone now...
Fast, deprive yourself of sleep, and do the Wim hoff breathing method before taking a short 20 minute nap. If you set an alarm to wake you suddenly then record what you experience during those intense REM naps, you may find yourself in some interesting situations where you are clearly experiencing as a memory events that have yet to happen. At least that's what I've experienced. When the events come to pass you may experience a bit of intense deja vu. Record your results.
@@RStell-wt5qr any specific event that you can share with us? Like your most shocking experience?
@@RStell-wt5qr Tell us more about your experiences. I am curious.
I don't mind the future coming. I just get a little sad when it suddenly gets up, put's on it's clothes and leaves.
It’s weird how Matt has some of Gabe’s memories...
PBS space time is a collective organism that feeds on astrophysics.
@watch Earthlings documentary This is exactly why people think vegans are pushy and annoying, you're hurting your cause go somewhere else
Maybe time is a 4th dimension element, that when seen in our 3d realm, is transient. It pervades and appears to "transit" through our dimension. Eg. Time outside of our universe is a not transient, and everything in our universe is simply a small portion of a greater universe outside it. Like a piece of paper with a drawing on it. The drawing would see a line being cut where the 4ty dimension scissors cut it, but would not see the scissors themselves or the hand doing the cutting etc.
Ive always though of space itself as a 4th dimension since any direction would be forwards theres no up down left or right in space
When the episode is near the end, I start to get anxious to hear him saying "spacetime" and that takes away my focus of the talk about spacetime
3:10
dang that rewind effect really effectively captured the piercing, head-splitting, squeal of a VHS
11:35" time is tracing the gradient away from lower entropy towards forming memories and correlation"... I am loving it
"Arrival"/"Story of Your Life" is a great Si-fi exploration into this topic
@watch Earthlings documentary not really relevant.
@@tisFrancesfault relevance is immaterial to true believers who love to preach and parade their moral superiority... You could have been talking about throwing a curve ball on a 3-1 count, it would have ended up the same response..
@watch Earthlings documentary You will only raise animosity towards your cause by pissing people off with irrelevant comments, which is a pity, because your cause is a good one.
@@vlada it would have made more sense if it was a response to your example because it could be argued that they were throwing their own curve ball...........one that wasn't covered in cow or horsehide.
No. That film is just beautiful nonsense.
Joke's on you, I can't remember any of what I just watched.
It's too advanced for us. Lol
I remember you going to say that!
I rememberd what haven't watched yet 😏
@rollinia
* You're
I was thinking about this video last week, finally I am actually seeing it lol 😂
“Assuming it isn’t destroyed by future violence”
touché.
"Our brains aren't rocks, despite the similarities in SOME cases" is the understatement of the year.
The simple answer is: "Because it hasn't happened yet."
According to my calculations, you are absolutely correct.
I remember the time in future when I will understand that I have to actually study and not watch these videos all day.
How can you see that's exactly what I'm doing here? Teleport much?
Can you remove from a table that which is not on the table?
No more than you can re-assemble that which has not been dis-assembled.
There are categories of impossibility; how many can you identify?
@@susanzoeckler4926 when did this become about you much?
@@jordobello My comment was a joke. So is this: It's always all about me.
I remember now that I was going to watch this video when it came out
I blame all my failures in life on the second law of thermodynamics! Entropy has put my life in total disarray...
"Obviously our brains aren't rocks, despite the similarity in some cases" ... BOOM! lol
Now, THAT was a statement even I could understand. I just about spit out my drink when I heard that.
Knew this would be a top comment.
The brain stores information in a specific way collecting information from all sensors available which is then encoded chemically (ionization-short term) or as new synapses (long term). But a rock has the ability change its structure based on what happens to it for example (heated by light, particles that hit the rock) all leave markings and in principle the information could be retrieved but in practice a only certain events remain recorder like impacts, animal traces etc. So it’s like a sort of recorder. But it doesn’t meant it can think of course.
Except for stoners.
Although not subjected to the forces of reentry, their brains burn up very fast.
@@Declan-pg8cg Marijuana is the devil.
I always hoped that some of my daydreams about the future were going to be forward memories. Where's my mansion?
Oh no
Your mansion is in the same place as tabletop fusion: always 5 years into the future... ;)
Same place as my flying car
Same place as World Peace 🌎 ✌
In the age of Google and being able to essentially know anything we want.. I love watching these and being so baffled and confused.
The simple version is: We don't remember the future because of causality. Things must happen for us to remember. If it hasn't happened yet it can't be remembered, because our mind hasn't perceived it
The title is absolutely just a stoned tweet
Oh that is why I clicked the video and the idea just clicked in my mind...
....I am starting to think this free will thing is in a losing boxing match with determinism. Guess I’ll smoke.
love the old youtube default picture you got there.
yes
@@Omar-em7rl Lmfao thanks you're the first person who recognized that I'm not using the current default profile picture but went out of my way to use the old one
@@orb3796 to be honest i missed it at first, then realized what i looked at 20 seconds later and scrolled back up to your comment, love people that are different like you.
"We hold an awareness of, say, the task we're doing and what steps we've completed."
Me with ADHD: Bet
Me also with ADHD: I’ll take that... wanna ride bikes? Oh! Squirrel!!
ADHD is the worst.
@rͬaͣрⷬiͥdͩ eͤvͮoͦ aids is the worst
@rͬaͣрⷬiͥdͩ eͤvͮoͦ It’s spelled CDO, with the letters in order.
Time inversion is a flaw in our mathematical equations. It's like imaginary numbers or repeating decimals or zero division.
The opposite of time forward is not time backward. It is only time slowed down or sped up. Chemical reactions only occur forward. We have never observed it any other way.
Oh man, I remember that old host, I liked him but Matt O’Dowd is favorable. Cheers and a toast to the many future space time episodes, though I can’t quite remember what they will be...
I always listen to this at 2am and have no clue what he is talking about but always act shocked at what he's saying. Good night.
I watched this after eating an edible and had an existential crisis
Great video but haven't watched yet 😂
I’d love to see that episode about the early universe and how its relative compactness means it was still low entropy despite being very uniform.
That combined with Penrose’s theory about how the states of the beginning and the end of our universe could be the same thing would be wonderful to hear more about. 😁
To see the future, you just have to accept and forget the past. Also a good understanding of myths and tvtropes can give you incredible forsight
The odd thing is, “remember(ing) the future” is an unexpectedly powerful decision-making technique.
The closest thing we got from that is intuitive forecast
As in imagining the future? :P Yeah... Actually, much of our memory is spent predicting the future. So perhaps the difference between past and future isn't so clear cut after all.
Think of yourself as an event. Your entire experience is an event. Wherever you are, you are in a relative position to other events. Where you are - is also When you are, on a spinning planet, pulled by the sun, etc., etc.
That said, you don't get to experience events that haven't happened, even if they "have happened" elsewhere ahead of your experience to have them if you are destined to experience them "when" it does. In other words, you can never say that you "knew that"... you are lying. You are just experiencing what's called confirmation bias.
We can predict the future just like we can predict the past, but it's much easier to predict/remember the past with much more accuracy.
@@Galdring what if this was (hypothetically) a little more concrete than just imagining the future? 😉
Matt, you could've made a joke by starting the show with the word "Spacetime" instead of ending with it, apart from that, it's a great episode, it's going to make my brain melt as usual
(it's a joke because as of now, I couldn't have possibly finished watching the video)
Memory was Philip K Dick's core focus in his philosophical exploration of existence.
1:39 - when Matt remembers his past as Gabe...
That's because they're correlated! :)
@@CATinBOOTS81 That's what I love about this channel: witty, intelligent responses. Thanks. :)
"we we remember the past but not the future"
Others : man, you're crazy, get a checkup.
PBS space time : well that seems interesting (^_-)
Yea others are DUMB
@@satvikvarun6386 indeed
I would replace "Man, you're crazy, get a checkup" with "Whatever you're smoking, I want some"
Did you mean, "I remember my we we"?
I love the attempt to bridge physics and consciousness.
"let's go as simpler as possible... _in the crazy energy of the early universe, a positron and a..."_
Well this is as simple as possible
@watch Earthlings documentary mmmm....eggs
@watch Earthlings documentary Amazing, but I believe you posted it in the wrong comment section
@watch Earthlings documentary look, I support a vegetarian/vegan lifestyle, but posting these comments on totally unrelated videos just harm the cause. It sometimes annoys people and it makes you seem like an extremist.
Have a nice day.
You could say the forwardness of memory is a spatial phenomenon. When you look at the whole universe at once, it _can_ be said to remember its future. A future collision between two objects is "remembered" by their current movement toward each other. The problem arises when we zoom in on only a portion of the universe. The information of a future collision is spread out, spatially, before the collision: to "remember" the future collision you have to know the present trajectories of these two far-apart objects. After the collision, you can find information about that collision recorded in each of the objects. The information has been smeared across both locations, so you no longer need to look at them both. This starts to sound familiar -- smearing, mixing, stirring, this _does_ have a direction, and we call that direction entropy.
That's what I was thinking, too; you can only remember the past because of locality. In the future, the information is elsewhere.
Do this. Put a spring on one of the objects and compress it. Let's call it a memory of a future collision. Set it to decompress back at a certain time in the future. Now say, by pure chance just when the spring is about to unwind an object passes by almost touching the spring. The elongating spring pushes the object away.
Play this backwards in your head. The other object impinges on the spring on our object, compresses it and then drifts away. So the compressed spring was a valid memory of the future collision because it pointed to an event in the future and was also causally linked to it.
One needs to remember that an impression from a past collision is in the end just an inference. You are able to make a correct deduction from the damage because it is highly unlikely that the damage was caused by some chance event like a random laser directed and applied in a very precise fashion. This is because we live in a high entropy universe where there are objects to collide into and also that entropy must decrease.
Future visual memory is even easier to make. Just let a memory convert to light and land on a white screen. We can remember simple shapes which would exist in the future briefly. Or even for a long time if the screen was a photographic film!
@@floriath the more detail you can perceive and process, the less often one of these backwards coincidences will convince you. even at the coarseness of human experience it basically never happens. if you track every particle the odds go to 0. it makes sense because entropy increases, so you're not gonna rewind exactly to a previous state in a complex system very often.
@@kevinmathewson4272 Entropy law only explains why it is not worth it remembering the future not why we can't do it.
Imagine a brain whose body is enclosed in a photographic film. Now let the brain on its own form a memory of seeing something green at 6 pm. The memory reverses at 6 pm and gets converted to green light which forms a green impression on the film outside. Future memorization here would work all the time!
@@floriath that's cool to think about. it relies on you having foreknowledge of the green thing at 6 pm though, so you can install the memory in advance, or you reading the person's mind and then changing the future.
Wow, these videos are phenomenal. The questions they raise are just mind-blowingly compelling.
"Always in motion, the future is." - Yoda
I can't believe I understood this video, actually, I have been able to understand videos from this channel for a while now. You have to understand that I've always been stupid and when I first started watching years ago I barely understood anything, but still liked the content. Look at me now, my brain doesn't hurt anymore ma!
I understand the more I watch them. This one went over my head completely
Because we dream the future and have the epiphany moment of that dream in what is called “Deja Vu”.
I've had an interesting thought: It seems to me that time *could* be flowing backwards, but we could never know it based off of the nature of our conscious experience.
To explain: even if time did flow backwards, from future to past, in each time step we would not remember the "previous" one (the future) because we have no memory of it, and we would instead remember the "next" one (the past) because we have memories encoded of it. Thus for every given moment of the present (including right now) we should feel as if time is moving forward, independent of an external, unobservable time flow whether it be congruent or contrary to the direction we experience it.
Time is relative, you have 2 people one of which is on earth and the other traveling 5/10ths the speed of light towards the andromeda galaxy, how do you determine which time is correct?
@@bakatemplargaming2430 You're right of course, relativity upends the notion of an objective universal clock even before we start involving phenomenological thought experiments.
Bro 🤯
@@flavertex658 If "time could be flowing backwards" then you have to ask yourself, what does the "flow" of time even mean? Why do you think it would be "flowing" at all. The only reason we might think it flows is because that's what we experience, and so wondering if in reality it might flow the other way even though we perceive it this way doesn't necessarily make that much sense. Especially when you consider what time would actually flow through. The idea that there is one present moment that is moving along the dimension of time would be the flow, but the rate that present moment changes could only really be described in terms of time itself, i.e. the present changes at a rate of 1 second per second.
I'll stop there, because I could probably talk in circles for days trying to explain what I mean and you might already get it. I guess my point is that is flowing independently of our perception of it, then its flow is a trait of time we cannot and have never observed.
@@rogercamel I think I get your point: that it's meaningless to talk about the world in terms of how it "really is" absent an observer, since such a state of the world could never be verified. If a hypothesis can't be verified by any empirical (that is, ultimately sensory) evidence in principle, as is the case for all arguments of the form "the world seems like x, but it's really y outside our perception" then by necessarity one's claim is kinda just null.
6:19
rock: i don't feel so good
Sometimes watching these videos makes me feel dumb, but reading the comment section always makes me feel like a genius
I am a simple man. I see Space Time video, I click.
I’m guessing it’s cuz my future self hasn’t had his coffee yet.
Radioactivity in forward time resembles random interactions of the asteroid in backward time. Perhaps time moves in both directions, increasing entropy in another sense while moving backwards.
Antimatter. That's why it misses. It went backward in time whilst we (as matter) are going forward. If time and space are one (spacetime) and it expands, time goes "forward" for us and backwards for the antimatter part of the universe. The antiverse/ universe theory...
So here is ultimate question:
When we invert time while observing quantum collapse, we will see very deterministic results. Does it say that the collapse is deterministic and not probabilistic?
Interesting point, if physics is perfectly symmetrical you'd think the probabilistic nature of quantum physics would result in a different past, albeit perhaps only slightly.
@watch Earthlings documentary wrong comment on the wrong vid my man, unless you're a troll or a bot
@watch Earthlings documentary
I agree with your general message but spamming this on unrelated videos is doing more harm than good.
@@xxportalxx. Hence, if the past is shifted (and thus, "self corrected")... The past would be changed simply by travelling backwards. But if one does that, then JUMPS into the future (and hence, beyond the point in which we jumped backwards)... Would the future, in turn, be changed due to the past being modified? As a mild offshoot of that question.
Thanks for the responses. I have always was sure that the Universe and all quantum effects are completely deterministic (either in a classical way or in a many world interpretation). I just wanna hear what scientists says about inversion and probabilistic
Most people would say "The past is gone, the future doesn't exist yet."
Aren't you that robot spider on help island
@@AdeonWriter No, but I've seen him in Caledon Oxbridge University on SL.
Neither “exist” both are just in your head. The only thing that exists is the present. And you can only experience the present. Once you try to think about the present it’s becomes the past.
@@AD-wg8ik QX
Most people would be right.
Nice video. Philochrony is the theory that describes the nature of time and demonstrates its existence. Time is magnitive: objective, Imperceptible (intervals) and measurable.
15 mins later & the only thing I understood is that my brain is a rock
ditto 😅
"If you can gaze into the future
You might think life would be a breeze
Seeing trouble from a distance
But it's not that easy!"
I mean at least you can mentally prepare yourself for Karen taking the kids.
Ahh raven :)
@@mjm3091 Is it not remarkably harder to live when you certainly knew how all of that is going to sh**
@@David-eg6sd I don't know, when I recognised that I will die, I started enjoying life.
That's so raven!!!
I read the title was like "How can you remember something, that has not happened yet" I mean I guess if you're really into sci-fi and have good understanding of science, an a awesome imagination. What you imagine can be sort of like remembering the future, because there is no one to disprove you wrong, or that it wouldn't be a thing in the future.
I always thought we cannot remember the future because it hasn’t happened yet. Thanks for clarifying that for me 🤙
It is no less 'real' than our relativistic present, or our 'past', according to general relativity. Your present is in someone else's future, and someone else's present is in your past. As Einstein said, "the distinction between past, present and future is only a stubbornly persistent illusion."
So... is destiny real? Theres nothing i can do to change my predestinated future?
@@florzinhaestudiosa8670free will is an illusion anyway
Ah yes, I do remember this one.
PBS is wonderful. Just wonderful.
11:15 I can't help but wonder if that strand is actually an errant eyebrow hair.
I really hope that they instead made an episode titled, "Why do we remember our future and not the past?" it would've really driven home the point that most physical theories are time symmetric.
Yeah the thermodynamic future perhaps. Anyway, we don't remember the future because we never absorb information from the future like we do from the past. Now you ask how we can achieve this. For remembering the past light hits our eyes and forms memories. Now reverse this. Create a (fake) memory of say looking at a red flash of light, disintegrate it and then create a red flash which goes out. Voila you remember the future.
How is that remembering the future?
Imagine it in reverse. The red flash hits your body and forms a memory. Your memory formed before the red flash and was formed FROM the red flash if you run it backwards.
Hope someobody understands this...
perfect memory is just knowledge, the same as perfect prediction is just knowledge. so long as you are not wrong, and you know literally everything, the past *and* the future are equally knowable and thus, effectively, both have already happened.
Do a decent dose of LSD and you'll start remembering the future lol
Oh, had a few weird ones my self
You kind of get the idea that reconciling QM, with the "sycamore of thermodynamics"(sic!) is as problematic as reconciling QM with GR.
A low entropy allows memory and correlations to build in one direction rather than the other. I had to write that down. Great video!
I was also wondering about the apparent contradiction of descriptions of entropy at the start of the universe. I'm still very confused, so I'm really looking forward to that potential video explaining "the degrees of freedom in the gravitational field" as Sir Penrose put it.