The Biggest Ideas in the Universe | 22. Cosmology
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- Опубликовано: 30 сен 2024
- The Biggest Ideas in the Universe is a series of videos where I talk informally about some of the fundamental concepts that help us understand our natural world. Exceedingly casual, not overly polished, and meant for absolutely everybody.
This is Idea #22, " Cosmology." Perhaps more a field of study than an "idea," but it is made possible by an extremely powerful idea: that our universe is uniform and simple enough to be understandable. We go through the expansion of space, the thermal history of what makes up the universe, and a bit about dark matter and the cosmic microwave background.
My web page: www.preposterou...
My RUclips channel: / seancarroll
Mindscape podcast: www.preposterou...
The Biggest Ideas playlist: • The Biggest Ideas in t...
Blog posts for the series: www.preposterou...
Background image: www.spaceteles...
#science #physics #ideas #universe #learning #cosmology #philosophy
I love how Sean is just a bust floating in space. Like a Boltzmann Bust
I find it very appropriate and appreciate that Prof. Sean can manipulate math models and equations to back up his topics and lectures. I love Neal Degrass Tyson as a speaker, representing the cosmos and being a great science communicator and advocate but he never busts out any math to back up his lectures which for me, is not as impressive as Prof. Sean's grasp of and display of the math that underpins and proves most or all of his videos topics and shows way more how and why we have the knowledge we have gained as a whole. And why the universe is the way it is. Bravo Sir.
Sean Carroll’s gently spoken manner plus his ability to explain this material is just the most wonderful way for us in the public to gain some insight into the beauty and wonder that is our universe. These videos are simply a gift to all.
I fell asleep listening to this and dreamed that my former First Sergeant was actually my high school PE teacher, and that he happened to be very well-versed in cosmology for some reason
Made up. It didn't even sound cool either...
@@josephhall5681 hello there little troll, aren't you cute...
Lol.
Well Sean Carrol does have quite the soothing voice.
I fall asleep listening to these every night for a month Atleast lok
Two years later and I still love coming back onto these. ❤
We can come back 5 years or 10 years and still be amazed.
One of the greatest communicators and ambassador of physics and cosmology since Carl Sagan.
"We're made of star stuff. We are a way for the cosmos to know itself"
- Carl Sagan
"Our universe is the ultimate spherical cow"
- Sean Carroll
LOL!
Ha. A Carl Sagan vid clip popped up on my youtube algorithm earlier today. Last night I watched a Freeman Dyson video & a Richard Feynman interview a couple days ago. I'm glad other people enjoying these as much as I am. Lol😹
Universe? Uni-verse? Hardly! It’s a novel at least; an epic, Opera, Trilogy, or Film series. And uni? Only one? Certainly multi is more likely, or at least a duet? So there is no universe, it’s a multopera! A Deutrilogy? A novel Multepic?
C’mon, folks! Think outside the bun!
I read Sean's books.
I listen to Sean's podcasts.
I watch Sean's videos.
I spend a lot of time with Sean... and I love it.
He’s awesome, his books are something special....
Isn't it weird to have a friend who knows nothing about you? lol
You’re not alone ;)
@@Psnym Wouldn't it be "he's not alone"?
Jeff Bass *we’re* not alone!
Sean..Your content will be counted as a treasure as this playlist matures ❤❤
Sean: Cosmological Principle... homogeneous and isotopic...
Me: DUDE! Did you finally get a haircut?!
Denis Goddard Lol, I laughed at this. jsk, he explained in an earlier video in the Biggest Ideas in the Universe series. The last 2 Big Ideas were recorded before he got it formalized(cut).
@@adhdasian1896 renormalized
@@Psnym The Cosmological constant is a well known fixture of the Universe.
Fascinating,Sean keep it coming.
Thanks Sean. I learn a little more every time I listen to your podcasts/lectures. Thanks for taking the time to educate and inform us. And thanks for referring to Schrödinger’s cat as awake or asleep. As a cat lover, that is so much easier to think about for me.
It's just amazing how knowledgeable Sean Carroll is and how well he presents complex stuff in an understandable way.
I hope we all get theoretical physics degrees at the end of this series.
Only if you do the associated mathematics.
Physicists are lame anyway, they are practically mathematicians.
No real urge to understand, and make sense of the fundamental stuff in this world.
All they want is to calculate.
@@nafnist ?
What exactly do You mean by "understand" ?
And what group of people (if any) do You think are in pursuit of "understanding and making sense of the fundamental stuff in this world" ?
Best regard.
@@mrdr9534 Shut up and calculate
nafnist There is no way to deeply understand the universe without the calculations. The quantification of the universe and its concepts is the only way to break through the biased lens of human perception and get a real glimpse at objective reality. I have a feeling you simply can’t handle the math and so you lash out against it altogether, like a child throwing a tantrum. Nice.
At 44:55, Sean writes:
log(eˣ) = x
From the context, the log's base is e (not 10) so it means:
logₑ(eˣ) = x
or
ln(eˣ) = x
Apparently, physicists assume *log* is a _natural_ logarithm (base e). However, engineers, calculators, and general convention all assume that *log* is a _common_ logarithm (base 10). That's a problem, isn't it? :-) Decades ago, I was taught that *log* has base 10 and *ln* has base e.
The international standard *ISO 80000-2* (section 12 "Exponential and logarithmic functions") describes this notation:
logₐ x : log to the base a of argument x.
ln x = logₑ x (natural logarithm).
lg x = log₁₀ x (decimal logarithm).
lb x = log₂ x (binary logarithm).
log x is used when the base does not need to be specified.
log x shall not be used in place of ln x, lg x, lb x, or logₑ x, log₁₀ x, log₂ x.
I recently adopted this standard a few weeks ago, which makes me the first person ever to do it! :-)
Thank you so much for this amazing series. Are you going to make videos about "String Theory" and/or "Loop Quantum Gravity"?
0:49 My new favourite phrase is "the universe is the ultimate spherical cow."
Dropping a like at 1sec into the video, I was waiting for this topic. One of my favorite fields in all of science. And I know Dr Carroll will do it justice, having owned and read his fantastic book, "
Spacetime and Geometry: An Introduction to General Relativity".
I am really impressed by your clear and professional presentation. I have the impression that I understand GR much more than e.g yesterday. Thank you very much indeed.
Many thanks again Professor Sean. I didn't get to see this until the Wed morning, but it was well worth waiting for, as always. And one of my personal favourite topics too.
As an amateur astronomer, who happens to find himself living in a Universe, and wondering about that, I reckon that makes me an amateur Cosmologist as well !! Thank you.
Sean you have been very very productive lately. I think that about 60% of my online listening is content of yours.
Exciting!!!
Prove it.
Same for me.
sundial is only possible on a flat earth. They have lied to us.
And 40% is pornhub
Thanks for taking the time to do this. I've really learned a lot.
nice hippo
yeah. it looks like a really really good hippo
22:20 ish, and forgive my ignorance here, but I understand that you are making the relativity point here, but if we were to be looking at the universe in its entirety, doesn't there by definition HAVE to be a center if everything is expanding at a constant rate as a whole. I may be missing something here, would love to be informed on this. Thanks for these videos, this series has been AMAZING!
Not every geometry needs to have a center, expansion or not. For example, there is no center point on the surface on a sphere, nor in a flat torus. Since the expansion is not an acceleration through space, there is no way to locally detect is as motion. If you were to define the universe in a more Newtonian way, then you might end up using a static background grid of space to plot out motion of galaxies and find an apparent center, but that grid is not physically real. You could just define a center into existence wherever you like just by choosing that grid. If you are taking into account that the space itself is expanding, and that the expansion looks the same no matter where you start looking, that apparent center goes away.
Ben Marolt thank you!
If you know the most basic cosmology 2d spacetime model youd not ask this question. You draw an x t coordinate axis. the x=constant lines are worldlines of galaxies (wlg )if you draw a t=0 vector it points between two of these (wlg) and the length of this vector is a(t) as t changes the distance changes equally between any two wlg that started at same distance and theres no spatial center to this. If you have an infinite forest of trees wheres the center. Nowhere. Wheres the center of an infinite plane Nowhere the is none or evrywhere every point can be center.
This one may be my favorite one yet!!! I actually feel like I understood everything he was saying. (As he said, cosmology is for simple minded people with short attention spans, hahaha!!!! :) ).
Amazing episode! So satisfying when all the subjects from all the other videos come together and creates something new (knowledge), but still familiar (our universe!)
What if Ariel knew more about Cosmology than we thought ?
21:00 I've heard you say a couple of times already that you don't like the balloon analogy, because space does not expand "into something". But, if you're living on the 2-dimesional surface of the balloon, it does not expand into another area either as the balloon grows. If you compare the radius of the balloon to our distance in time from the big bang (so you could call the entire thing "arearadius" or "areatime", just as we speak of "spacetime", the area is growing as the radius increases, just as our space grows as time progresses. I think that is a valid analogy, and by taking away one space dimension we get a three-dimensional "areatime" that we can at least comprehend with brains that are hardwired for imagining 3-dimensional constructs. I like that analogy especially for pointing out how little sense it makes to ask what was "before the big bang": In a balloon-like areatime this would be equivalent to asking, what's "inside the center"
good point
i like the balloon analogy also. flatland but not flat
How have I not found this channel until now?! Brilliant content, sir! 😊👍
Carroll's Theorem: All parallelograms tilt to the right.
That way they look like Tennessee.
@@beenaplumber8379 uuhb bb ubbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbububybbbbbbbbbybubbbbbbbbnbnbbbbbnbnrnnnnnnnnnn
@@beenaplumber8379 uuhb bb ubbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbububybbbbbbbbbybubbbbbbbbnbnbbbbbnbnrnnnnnnnnnn
Both you and they are right
1:20:00 I don't like the term "make fun of", and I don't see why anybody whose ever been on the receiving end of a bully would. I always replace it with "ridicule", to promote a more accurate connotation. But, in the case of _recombination_ , I would have to go with "make light of". (Note: That's a pun, if you don't realize)
Note #2: no center. How could there be no center? If the U started from a singularity wouldn’t all matter scatter uniformly from it. In other words I imagine it like some kind of an “explosion” which would leave some of the matter to be on the outer edge of the explosion and some going behind it (probably a little bit slower). I can imagine if that’s the case that the center could be tracked down by measuring the relative velocities between galaxies.
You can't do that, as the relative velocity bw galaxies depends on which galaxy you are in. Wherever you are the closer ones move away slower than the farther away ones.
I think imagining the start of universal expansion as a physical explosion is a limited analogy. That singularity is beyond/before the time where physics and intuition make sense. Something really different might happen at those really really high energy densities that we may be unable to predict when tracking backwards. It may be better to start imagining just after that moment, with an already centerless yet very dense U. Or, if you must take it back to a single "location", (even though there would have been nothing else to compare coordinates to define a location,) consider that all points of spacetime would have been at the same location in that singularity, with no one point being special. There is no outside rim if all the points are in the same place, or you could say every point is equally on the outside. In that light, you could say every point is equally the center of the universe, which I think is just another way to say there is no center.
@@michaelsommers2356 I like to think it as an infinite ruler. You can compress the notches infinitely close together (big bang) but you're still going to have an infinite ruler.
If you know the most basic cosmology 2d spacetime model youd not ask this question. You draw an x t coordinate axis. the x=constant lines are worldlines of galaxies (wlg )if you draw a t=0 vector it points between two of these (wlg) and the length of this vector is a(t) as t changes the distance changes equally between any two wlg that started at same distance and theres no spatial center to this. If you have an infinite forest of trees wheres the center. Nowhere
Wheres the center of an infinite plane Nowhere the is none or everywhere every point can be center.
Brilliant! The skill of the teacher has to be inversely proportional to the ability of the audience.
I think I understood acoustic oscillations for the first time and where that CMB graph came from.
What a privilege to have access to this great communicator. Making it simple is not easy.
Many thanks
Excellent comment
Making it simple is not easy......
Copyright that
Or as Steve Jobs puts it: Simplicity is the ultimate sophistication 😉
Inverse proportional would mean that teacher that has great knowledge of the subject and with a high pedagogical aptitude is unable to pass knowledge to a highly gifted student, but a teacher with low skills would be successful in bringing the same student to a high level of understanding the subject.
But that is not quite right is it?
The relation between teacher skill and student ability, in regards of successfully passing the knowledge can only be direct linear.
My cat likes Astrology so I put him in a box. Now I don’t know what he thinks. Ah he got out !
If je likes astrology hes doomed. If he likes astronomy he'll likely find a way to survive. Its funny if in the early times you were an astrologer, you were a genius
there lies the beginning of modern astronomy. If in modern times you like astronomy youre crazy.... half the women I know like astronomy.... yep and theyre crazy.
I meant astrology for the crazy part. Of course astrology is just a very smart way women use to break the ice. Dark bar woman with cugarette in hand ... you must be a leo no???
Another good lecture on cosmology is by prof. Leonard Susskind in stanford university
Yeah Lenny is Amazing so is Sean; though Seans lecture here is less mathematical and for a wider audience. Heres one that while has math
doesn't use too much technical stuff ruclips.net/video/saf-1OZrVh4/видео.html theres 3 parts to it.
What an absolutely wonderful lecture. er, I mean Video.
"Lecture in disguise"
This is a truly great series because of so many interesting topics. Are Axions a possible source of dark matter in the early universe?
Absolutely fantastic summary! Congratulations. Never stop giving these lectures.
Prof. Sean Carroll isn't there going to be any video on Relativity? By the way, love your videos
Look up the Gravity episode. Lots of stuff about general relativity there.
As someone here said Susskinds Lectures on relativity are really good. Ive watched all of em multiple times. The ones on cosmology too. In this channel theres some stuff ruclips.net/video/saf-1OZrVh4/видео.html
And Sean has a real good introductory to advanced book thats used in many universities to introduce the subject. Also recomend PBS spacetime. you need many sources to learn relativity. Its not easy subject.
Vacuum has energy, therefore our expanding universe is creating infinite amount of energy. Why? Because, if our universe is not embedded in a larger space and is expanding all by itself then it is creating infinite volume of vacuum for a long long time, perhaps a google years or longer. Does this sound right ?
Dont know what to tell you cuz as I understand it from something I read energy conservation can be violated in general relativity
Sean Carroll is a superhero! Sir, you are the professor I wish I had and the professor I am so honored to have access to and could listen to you forever. What a mind and educator. Even when I don’t completely follow all the complexities, I find I learn something each time I listen. Your passion is infectious!
"The Best Content"
Amazing series going on
Thank you so much Prof.Carroll
Hubble gives me hope in humanity he started out a lawyer and became a scientist
Do you realize that with enough background noise and enough distance from my phone you sound just like Alan Alda. Not too sure how you should feel about that.
I wonder if you can detect gravitational waves beyond/further back in time from the CMB. And will they be able to help you figure out what caused the perturbations?
yes for sure we will be able to do this
A question:
-- Is Einstein's cosmological constant == (same) as "dark energy"
-- Why has over time the term "dark energy" replaced the original term "cosmological constant"
-- Are the two terms identical or not -- and why
Many thanks in advance
The "cosmological constant" is a factor in the equation, put in before there was any physics for it to correspond to. "Dark Energy" is the physics that was discovered in 1995, and it uses a non-zero value of the C.C. to describe its effects.
It's like, "what's the difference between momentum in the lab and the symbol rho in the formula?"
Another thing, Sean gave only the modern writing of Lambda. I believe Einstein's original C.C. was written on the other side of the equation. That is, do you interpret it as a fudge factor in the curvature of spacetime, or something _in_ spacetime that contributes to the total energy of a region?
If you look at the Wikipedia page, you'll see that D.E. being the C.C. is just one possibility.
Maybe I'm missing something? but when we look at the most distant galaxies with large red shifts we are also looking back in time, so how do we know that space is expanding and causing the redshift rather than that things were moving apart faster in the early stages of the universe?
i think... space HAS to be expanding if distant galaxies are moving away from each other. Otherwise there's nowhere for them to go
Oh my. If studying stars is this messy, some galaxies must be Messier.
Invigoratiswatudunn
This guy sounds a little bit like Alan Alda
Ha ha yes.
I had a major in the humanities, but took a Cosmology course in college. In retrospect, I value that one over any other and still have my notes, decades later. I know a lot has changed in the intervening decades, and have somewhat kept up with the field. I’m looking forward to this lecture with special interest.
I appreciate Sean Carroll so much, I’m happy Joe Rogan had him on and introduced me to one of my favorite teachers. (Even though I’ve never taken an actual class, I learn so much from his videos)
Sean Carroll, the Bob Ross of science
This connection between dark matter and the scale deviations of the CMB.... a dynamite explanation. 1:46:38
16:45 Cat has a question.
If there is no center, and everything is "moving away from everything else." , as Sean stated then some things are moving closer because otherwise you would have a uniform direction things were moving. They would be moving in a ripple effect because in order for things to be moving away from each other there has to be a point which they are moving away from, wouldn't it? By moving away from each other is does this and that would also give the universe a center, which would be found by tracing back to the point of expansion. But yet what this guy said contradicts.
@@michaelsommers2356 Im sorry but this is irrelevant to my statement
@@michaelsommers2356 then you didn't comprehend my question?
@@michaelsommers2356 lol....it doesn't need rewritten. It needs re-read, by you.
i got drunk too!
16:45 Sean Carroll is a cat guy confirmed. Damn do I hope to bump into you at a Flyers or Phillies or Sixers, hell even a Wildcats basketball game one day. I'd say God Bless, but since I know your deal, I'll just say I hope you have a great day Sean. Thank you for teaching me so much over the last few years. You've made a bigger impact in my life than you can ever imagine.
I love this series! Half of what he says goes way over my head. The other half goes way, way over my head.
If there was a big bang...then everything should be expanding away from a single point. The universe should not appear to be uniform, or the same in every direction.
If there was a big bang 14 Billion years ago...then the Universe can not be infinity large! Otherwise the matter ejected from the big bang would have had to travel much much faster than the speed of light forever.
Since there is a speed limit in the universe, then there is no way for two objects in this Universe to be infinitely far away from each other given the 14 Billion years of travel time.
how can we believe in the big bang but also believe there is no center to the universe?
if there was a point that everything expanded from, wouldn't that still be the center? can we not tell where that is from the CMB?
if the universe started from "big bang" would that point of start be the center? How come there is no center?
The big bang theory falls apart (/ is not describing reality) at the very beginning as you get that singularity and at any other time you have an infinite universe already.
Also, even if there is an actual center, none of the physics of the universe cares about it.
Thanks for your whole video series. It does not look like you respond to questions, but i will ask one anyway. What do you think about Sabine Hossenfelder's video on "New Evidence against the Standard Model of Cosmology"? Do you agree with the concepts and papers she references?
- ruclips.net/video/JETGS64kTys/видео.html
how come diameter of universe 93 billion where as age of the universe is 13.8 billion ?
@@michaelsommers2356 does that mean we can see an object locating at 93 billion light year?
@@michaelsommers2356 so you mean we only can only see an object at 13.7 billion ly?
When do sapiens drop the whole big bang idea? Redshift observed is just a gravitational distortion. Not only are light paths bent by gravity, frequency is stretched over time.
I always knew that doing SOME exercise was infinitely more than none . Now I have mathematical proof . Thank you prof . Carroll . ♥️ from 🇨🇦
I taught this man everything he knows, and now I can't even get him to send me an autographed-copy of _The_ _Biggest_ _Ideas_ _in_ _the_ _Universe._ Back during his "Swiss Patent Clerk" days, I remember when he used to believe that Noether's Theorem had something to do with disproving the luminiferous aether and that "cosmology" was the study and application of beauty treatment. He was an okay student, and I'm very proud of him. I want that book now!
Hmm, perhaps the limit as ego goes to infinity sets the boundary condition for book transmission?
I love your stuff ~ pity about the multiverser..Everett Song
Neutron decay cosmology. One Neutron in to event horizon, one neutron out in deepest voids. Conservation of all domains.
We live on minimal Klein surface
Sin(cos(u/2)cos(v/2),cos(u/2)sin(v/2),sin(u)/2) 0
Dr. Carroll- first of all, thank you again and again for this series. not only has it satisfied my curiosity on a level no science communicator has been able to, its helped keep me, and I'm sure so many others, sane during this ....interesting time.
maybe I missed it, but aside from recombination happening at BB+380,000 years I was wondering if you could mention the times in relation to the distinct events in thermal history. how soon after the big bang did nucleosynthesis occur, for instance?
thank you again.
overlaps---> gaps and symmetries, eqn to predict symmetry breaking outcome, even for spontaneous symm breaking, outcome can already be know, like kicking an acorn, or a [ine cone, and knowing which way each vertex will point before even kicking it. like called cards and dice, translated into book words, translated into heard convos in public domain while flipping pages in a boiok synched.
Did not Hubble do something along the lines of the individual who took the picture of an eclipse proving an Einstein Theory?
Hubble used a hypothesis developed by Henrietta Leavitt's period luminosity relation work.
Did Einstein's photographer win a Nobel Prize?
Big Bang? I thought LeMatre came earlier.
Effectively, the same problematic related to understanding natural forces (including gravitation), structure of our universe, motions and interactions among elementary and other particles is part of generalized “matter-waves and wave-particle duality theory”. See much more here (download PDF book): mastersonics.com/documents/revision_of_the_particle-wave_dualism.pdf
I've recently come to the conclusion that, altho the CMB is indeed a record of the time soon after the big bang whe the usiverse cooled to below plasma temperature, since then there has been so much star, galaxy and planetatry formation that the thermal signature of so much molecular chemistry that has also been red-shifted to microwave levels,;the fine-structure of the ripples in CMB are so washed out that there's nothing it can reliably say about cosmogenesis.
Leavitt wasn't using parallax to measure distances to Cepheid variables. She was cataloging stars in the Large Magellanic Cloud, and observed the relationship in the Cepheid variables there. Since all the stars in the Large Magellanic Cloud are all roughly the same distance away, she observed the relationship between period and APPARENT luminosity.
22:02 I like to think that EVERY point is the "center" of the Universe. Under this perspective, the Big Bang happened everywhere. Also, under this perspective, each person can be said to be "The Center of the Universe."
I am reminded of a little Einsteinian anecdote I once read, that went something like this:
Assistant: “Doctor Einstein, I notice your examination paper has the exact same questions as last years test.
Einstein: Yes that is true. But the answers have changed.
Fairies and goblins might exist. God and dark matter might exist. I believe Steven Hawking at one time thought that an event horizon might exist. But electricity, magnetism and gravity do exist. Occam's Razor is the principle that, "non sunt multiplicanda entia praeter necessitatem" [i.e., "don't multiply the agents in a theory beyond what's necessary."] If two competing theories explain a single phenomenon, and they both generally reach the same conclusion, and they are both equally persuasive and convincing, and they both explain the problem or situation satisfactorily, the logician should always pick the less complex one. The one with the fewer number of moving parts, so to speak, is most likely to be correct.
“Space News from the Electric Universe” provides the counterweight to a variety of views held by the mainstream. The E.U. maintain that electricity is in fact the primal force in the universe. Their view allows many of these questions to be resolved through the known mechanisms of plasma physics and electricity. Happy hunting.
You say Universe has no center. Let's imagine the Big Bang ball, it ought to have a central point with coordinates, x1, y1, z1 & t1. What happened to that point? Where is that point now? How can we comprehend a no-center observable universe? That is same as saying all points in the universe (though expanding) is equidistant from each other (and it has been same since Big Bang)? Difficult to imagine???
8 min oleber's paradox, volumetrics nolocal nodal geodesics, brownian motion isnt Brownian motion, the convection zones in Suns to give their frequency of magnstroms... the rise and fall of the nile.
The fact that you can put those equations into words and vise versa off the top of your head speaks to your understanding of the subject matter. Pretty impressive. Thanks for the insights and not talking down to us. I find the mathamatics essential to understanding physics.
If Einstein had faith in his theory, then he should have predicted an expanding universe. So, say it like it is: the cosmological constant is the biggest blunder he ever made. Almost on par with his stubborn opposition to quantum mechanics.
Wow
Is there a coloration between how much the universe expands and how much matter and spacetime black holes consumes? Could black holes be the reason why space is expanding?
Since the biggest black holes are in the centers of galaxies and they are fundamentally the rulers of those galaxies. Meaning the galaxies follow the path of the black hole, like our solar system follows our sun.
Another Quantum Interpretation
Imagine a simple square maze made-up of many rows where the entrance is at the corner of the first row. Humans walk down the row and when they come to the end, there is an opening to the next row, and so on, until they come to the end where there is a door to the outside.
However, the walls of the maze are made of a mesh, where small insects can pass thru unencumbered. The insects can negotiate the entire maze by going a length d. Humans will have to travel d^2 a much longer trip to get outside. Also, the insects have access to a wider region. However, if the insects want food or water, that only humans possess, they may need to ride with the humans for a while going the long way with them.
The universe follows a similar paradigm, but the rows are much closer, and in addition, it performs this feat in all 3-dimensions, rows, columns, and sheets. Hence particles are small objects and can appear as spread-out waves because they can easily distribute thru the partitions. They can interact with other particles wave-like but must reveal their true small particle nature when interacting with large objects, which shunts their ability to spread thru the separation.
Consequently, a single photon is wavelike up until, for example, it actually hits the screen in the double-slit experiment, or the electron is wavelike up until it enters a vapor chamber. Also, a cat, a flask, or a hammer are never in a superposition of states. The walls are so thin that even a most superficial sensitive interaction with a large object turns it into a small object for at least an instant, but might enable it to start anew as wave-like when it escapes the grasp of the large object. It is the hidden structure of the universe that explains and describes these and other of nature's “tricks.”
Don Wortzman
wortzman@gmail.com
I have a question of light. Let's think of the following experiment. A flash light in a closed room with walls made of mirrors. When the flashlight is turned off why don't photons continue to bounce around. Where do they go? Do they lose their energy, and disappear, what do they change to?
This is by comparison to the light from the stars which travels so long from the moment they were emitted.
Thank you for explaining the modified gravity theory, there are some dubious other you tubers
I left this on in the background while I was painting and now I have a strange urge to walk naked into my back yard and stare into the star strewn depths of an incomprehensibly vast and ancient universe, stare in breathless wonder and know with utter certainty that cosmology is so far beyond my ability to comprehend that I might as well be throwing twinkies into the sky to see if anything up there is close enough to poke with a stick. Ah well, plenty of content on RUclips that will make me feel like a genius after watching it for ten minutes, plenty plenty. Actually I very much enjoyed the video and I will likely watch it again with my entire brain engaged.
Based on what you said just before 50:00, black holes must produce matter (from hydrogen on up through the heaviest elements) in a region where light gains enough energy to interact and produce that matter and fling it into the space surrounding the black hole. Some of this matter must obtain escape velocity. Crucially, a black hole must be a matter factory. Lighter or more energetic elements are more likely to obtain escape velocity. This should correspond to the relative abundance of elements in a galaxy and may be related to the mass and spin of the black hole. Super massive black holes may create their own galaxies! It also says that we are more likely to find life at our radial distance or further if star formation corresponds to density. Galaxies grow to a certain size based on the black hole mass and spin. A black hole massive enough to produce matter in this fashion must grow by the mass generated in this energy density region. Either gravity wins and this region eventually falls inside the event horizon or the black hole is in a run away positive feedback loop constantly increasing in mass.
I don't understand how space is flat but mass curves spacetime. Those seem incompatible facts. If every star, planet, and dust particle is warping spacetime to create gravity, isn't that at odds with saying that space is flat?
Question for people who have read 'something deeply hidden', is it worth the read if i have already watched almost every one of Seans lectures on QM and spacetime emergence?
The universe is amazing
I am very grateful that you've taken the time (significant amount) to do all these and answer questions is very commendable to say the least. I wish I had an opportunity to meet and learn from, no, exchange ideas with you. I sent you a invite on Linkedin.
The assumption that the universe is uniform, isn't this more of an assumption of uniformity over time given our observations represent a cross section of how things look over a very wide period of time? Does this also imply further assumptions about other properties and constants remaining, er, constant over that large window of time? Not explaining this well, but it seems we assume a lot about how the universe is 'now' based on many observations of points in the past. It's there enough 'stuff' that is 'nearby' aka 'recent' to mean this is a reasonable thing to do?
Why does taking the square root of a number occur so frequently in so many relativistic, cosmological, and physics equations. It seems like the square root is some sort of magical thing like Pi or something.
If farther objects are moving away from us faster, and farther objects are further back in time, doesn't that mean the expansion is slowing the closer you get to present time? I had that thought one day, and I can't seem to wrap my head around why it's wrong.
How natural is our universe?
(A universe which is natural means that its laws are inevitable and predictable. An unnatural universe is one which is based on a peculiar permutation of the laws of nature, among the almost limitless possible permutations, which enables conditions in the universe to be conducive for life to arise and exist. A universe that is natural is knowable, at least theoretically. An unnatural universe is not knowable, since its laws are fine-tuned and do not make any logical sense).
The photons of the early universe are gone. The only thing left is the weakly interacting neutrinos with non-zero mass. As the universe expands, they have fewer opportunities to interact with anything other than the curvature of ST which they are curving. There should be high density regions of neutrinos.
21:11 There is a chance that the Universe is expanding into dark matter, since there's so much of it.
Don't tell me all that dark matter is also expanding.
I mean you have a closed mind. You assume dark matter came out of "Big Bang", same as regular matter. That's a closed mind.
Google closed mind, see if say "present evidence."
@@michaelsommers2356 Is it nonsensical? Ah yes, you would know.
@@michaelsommers2356 This not your first salvo and I'm the attacker?
Comforting words for people with obesitas ....I am expanding naturally just like the galaxy ;-)
I don’t love analogies in general myself but I challenge anyone to show me the direct center of a loaf of bread.😂❤
Fantastic! i like your calm way of of presenting. I hope you dont mind if i also use this particular video for meditation :-)
(and i've also started studying maths and physics, it's a huge pleasure to be able to at least somewhat follow videos like this.)
Those who question the use of the term "recombination" aren't trying to be cute; they're legitimately confused because their introduction to the topic is by way of "the era of recombination" and so if there's an era of recombination it stands to reason that there must have been an earlier era where the original combining took place...
they should measure how rapidly 2 galaxies 10 ly distant from us and 10 ly distant from each other are separating to pin down the hubble constant