The mind-bending physics of time

The mind-bending physics of time | Sean Carroll

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Күн бұрын

How the Big Bang gave us time, explained by theoretical physicist Sean Carroll.
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In this Big Think interview, theoretical physicist Sean Carroll discusses the concept of time and the mysteries surrounding its properties. He notes that while we use the word "time" frequently in everyday language, the real puzzles arise when we consider the properties of time, such as the past, present, and future, and the fact that we can affect the future but not the past.
Carroll also discusses the concept of entropy, which is a measure of how disorganized or random a system is, and the second law of thermodynamics, which states that there is a natural tendency for things in the universe to go from a state of low entropy to high entropy. He explains that the arrow of time, or the perceived difference between the past and the future, arises due to the influence of the Big Bang and the fact that the universe began in a state of low entropy.
Carroll also touches on the possibility of time travel and the concept of the multiverse.
Read the video transcript ► bigthink.com/series/explain-i...
0:00 What is time?
1:32 How the Big Bang gave us time
3:31 How entropy creates the experience of time
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About Sean Carroll:
Dr. Sean Carroll is Homewood Professor of Natural Philosophy - in effect, a joint appointment between physics and philosophy - at Johns Hopkins University in Baltimore, and fractal faculty at the Santa Fe Institute. Most of his career has been spent doing research on cosmology, field theory, and gravitation, looking at topics such as dark matter and dark energy, modified gravity, topological defects, extra dimensions, and violations of fundamental symmetries. These days, his focus has shifted to more foundational questions, both in quantum mechanics (origin of probability, emergence of space and time) and statistical mechanics (entropy and the arrow of time, emergence and causation, dynamics of complexity), bringing a more philosophical dimension to his work.
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Пікірлер: 1 700

@bigthink Жыл бұрын

Watch our full interview, "The Universe in 90 Minutes," with Sean Carroll: kzfaq.info/get/bejne/qrNkpq-e2Ze5mWw.html

@jokrg Жыл бұрын

Pretty cool stuff! I like the direction this idea was taken in the “Rise Of The Moments” books by Carl L. Gabriel.

@educatedguest1510 Жыл бұрын

"Theory is when everything is known, but nothing works. Practice is when everything works, but no one knows why. We combine theory and practice: nothing works and no one knows why!" Albert Einstein Sean Carroll have not read "Time Matters eBook".

@rafars2246 Жыл бұрын

We make up time in our heads to make sense of things we do every day, but time doesn't exist.

@alexgoslar4057 Жыл бұрын

There is a symbiotic relationship between consumerism and industrialization. But clean energy and green transition are not intrinsic parts of this equation because reversing the climate digression does not generate income. One way of integrating environmental issues is by considering the climate as a commodity that has its own fungible and tradable value. And convincing customers that the most desirable commodity is the climate and that climate currency supersedes the value of any other commodity.

@davidharrison8975 Жыл бұрын

Time isn't anything more than a human perception. A measurement between one event and another. The "phisics" of time is bunk.

@routex1 Жыл бұрын

Sean Carrol is so articulate and masterful at summarizing big concepts to the laymen. His Mindscape podcast is a true gem.

@bobbeckstead8340 Жыл бұрын

Articulateness and masterful summarization are not discovery. They are the tokens of entertainers and con men.

@user-kz2qh6zd6m Жыл бұрын

Hmmm maybe because Oxygen gives both birth and rebirth but also is a very volatile carbon element…meaning energy is not created nor destroyed. And we all know the term “oxidation.” What is that? Hmmmm oxygen, oxidation… hmmmm. So oxygen both provides life and at the same time kill’s biological material. we know when everything is crumbling around us. And you’re an idiot because there’s more than 3 dimensions and that’s the simple conclusion of moving a spacecraft from the ground to past the atmosphere. You don’t need to be a biologist or scientist at all when it comes to energy. We cannot create nor destroy it. Simple as that. Let’s not forget Trump saying “clean coal”😂😂😂haha I love it. What a fucking idiot. Let’s not forget there’s an entire county burning because of coal and it’s still on fire 30 years after. Sounds familiar right? “Anti-oxidation or anti-oxidants” hmmm interesting. 😂and what has the drug and food administration done ? Nothing to fix the problem we have. And when was that? Oh during the four year trump one time president 😂

@user-kz2qh6zd6m Жыл бұрын

“Thermal equilibrium is found in a test tube” doesn’t have anything to do with real solar rays. It’s a fake truck republicans use because when solar panels are finally set up they do actually work. But so many of these asshole republicans have money invested in coal and oil (thank you bush 😂 you didn’t do anything)

@bobbeckstead8340 Жыл бұрын

@@user-kz2qh6zd6m You're blathering.

@bobbeckstead8340 Жыл бұрын

@@user-kz2qh6zd6m You gibber.

@jmac6248 Жыл бұрын

I heard a really good time travel joke tomorrow.

@lunam7249 Жыл бұрын

i know, i laughed about it yesterday.....

@kevinbeazy Жыл бұрын

Haha love it

@anuraagdhanik5110 Жыл бұрын

Finally I found you.. aren't you telling about the joke I told you 2 years ago?

@adamdel4 11 ай бұрын

I’m not going to get it.

@shanu7uday 11 ай бұрын

Please check your facts! I’m yet to tell that joke to you yesterday.

@emmahoulihan9606 3 ай бұрын

What I love about this video is how interdisciplinary it is. From starting with linguistics and breaking down the definition of time, to describing the sociological notions of time, shows how all these modes of studying offer some part of the puzzle that is understanding our universe. I was particularly awestruck by the perfume analogy, which I argue to be a poem. Utilising such a beautiful example to describe the nature of our world made me tear up, again emphasising the importance of literature and creativity in asking questions about our existence!!! Wonderful!!

@RogerMillerInVA Жыл бұрын

You make such lucid, clean, and clear videos. Your pacing, content, and imagery are pitch-perfect. Thank you.

@GeorgeHull Жыл бұрын

I understood entropy so easy when he talks...if I had a teacher like him in school...I would loved to learn more.

@jesusbermudez6775 11 ай бұрын

Yes, I found his explanation of entropy quite clear.

@alexgoslar4057 Жыл бұрын

I love your explanation, Sean Carroll. It is a keeper. Personally, I am making difference between time and timing. While time is immeasurable, timing is within a measurable scope.

@ruellerz 10 ай бұрын

Sean Carroll's mind takes flight, Unraveling time's mysteries, day and night. Physics' dance, a mesmerizing show, With each tick and tock, new insights we'll know.

@hamtoriz1084 Жыл бұрын

i could listen to him talk forever. it's so fascinating and intellectually stimulating, yet easy to understand.

@michael-4k4000 Ай бұрын

I like Neil or Brian Coxs voice better

@aromaticsnail Жыл бұрын

It amazes me how Sean Caroll can talk about such profound topics in such a clear way

@daleviker5884 Жыл бұрын

Yes, and if they make a movie of his life he should be played by Steve Buscemi.

@Sky-B14916 Жыл бұрын

When people say they don't have time ,they are always true ....they don't actually have time 😂

@willdesouza3968 Жыл бұрын

time has them

@EefLeaf01 Жыл бұрын

@@willdesouza3968 right where it wants them >:)

@wailinburnin Жыл бұрын

I'm with Robert Hunter as rhythmically phrased by Jerry Garcia: "Where does the time go?"

@Sky-B14916 Жыл бұрын

@@wailinburnin time goes far beyond expectations 👀

@dennisgalvin2521 Жыл бұрын

@@wailinburnin Where does the time go go? "It's around in a circle shouldn't we know, the clock and the calendar tell us of it's way's 24 hours 365 days. So as for this mystery that's dumbfounded generations, it's just an illusion from the harnessing of Earth's rotations". Bruce Dillon.

@Aryan37419 Ай бұрын

This video is a fascinating exploration of the interconnectedness of time and entropy. Sean Carroll does an excellent job of breaking down complex concepts and presenting them in a way that's accessible and thought-provoking. The idea that time is merely a label we use to distinguish events is mind-boggling, and the discussion on the arrow of time and its connection to the Big Bang is truly intriguing. I appreciate Carroll's challenge to the notion that life is a fight against increasing entropy, emphasizing that life actually owes its existence to the increase in entropy. It's a fresh perspective that opens up new possibilities for understanding the emergence of complexity in the universe. Overall, this video has sparked my curiosity and left me with a lot to ponder.

@nigelskipping7941 Жыл бұрын

I am a teacher and I tried to explain Time to them but they asked so many questions I ran out of time and the bell rang! Then, as they walked out, they got it!

@tokas-kb6rb 23 күн бұрын

Don’t lie

@billcook7483 12 күн бұрын

Yeah, like we believe you , right ?

@Leo.Wirabuana Жыл бұрын

Best Teacher Sean Carroll.

@supernatural_forces Жыл бұрын

Have you heard of Brian Greene ? See, 'What was God doing before Creation?' from the channel Rational Believer. Probably you would get something more enlightening. Though there's a flaw in this question, its just for conceptualization.

@HIIIBEAR Жыл бұрын

These videos are so well made.

@ahedkhattar667 Жыл бұрын

Big think professional editing+sean carroll brilliant presentation= an absolute masterpiece

@It__From__Bit Жыл бұрын

Sean says the universe began at it's lowest state of entropy and has been getting higher and higher ever since. Entropy is defined as "a lack of order or predictability; gradual decline into disorder." But when the universe began forming galaxies, solar systems, suns, and planets, it actually became far more ordered than how it began. It just stared out as a mass of unorganized matter and energy, then organized itself into the structures we see today. This seems to contradict what Sean is saying.

@mccorkleee3375 5 ай бұрын

You’re misunderstanding entropy. Don’t look at individual galaxies and solar systems, you may look at the entire universe as a whole. You’re right, it initially started out as one glob (low entropy) and is spreading out and developing new celestial bodies over time (high entropy.) The matter on earth and in our solar system/galaxy has come from many, many dead stars and galaxies before us.

@dentistrider3874 Жыл бұрын

I had a question very related to this a few weeks ago: "How could life have come about if the entropy of a system has to increase?" The answer I found is that the entropy of a *part* of a system can decrease or stay the same if the entropy of a whole system continues to increase. And life, really, as he said, is a system that feeds off of entropy, we are fine tuned by the edge of evolution to adapt to change and to overcome it, in a reasonably stable solar system with a constant source of energy and somewhat constant conditions.

@davidreidenberg9941 Жыл бұрын

Exactly. Entropy is always increasing ON THE COSMIC SCALE. That doesn’t mean that occasionally local areas can experience a decrease in entropy. Living systems maintain a low entropy state only because they interact with their environment. The real mystery is what caused the low entropy state to begin with.

@Trimmxthy Жыл бұрын

@@davidreidenberg9941 Imagine the cosmic scale is just a local part of an even bigger scale 😅

@batouttahell454 25 күн бұрын

Is there a God in this?

@dentistrider3874 24 күн бұрын

@@batouttahell454 In any serious discussion of cosmology or physics there never is.

@Polymathically Жыл бұрын

I know that time isn't linear. We just think it is due to the limitations of human perception. I occasionally have dreams that come true. I'm not talking metaphorically, or about deja vu. I mean dreams that are very brief, but clear visions of random future moments. Just long enough to get the layout of a place or part of a sentence. It's never anything useful, like saving lives or winning lotto numbers. And I never know the context or how long it'll be before it happens. Sometimes it takes weeks, months, even years. I also have memories of moments that apparently never occurred (just like the Mandela Effect, but in my personal life), and objects have either moved or vanished entirely. As someone who studies science, the fact that I can't prove or replicate any of this is incredibly annoying. It sounds like symptoms of schizophrenia, but all the therapists I've had over the years have said no. My current therapist has even suggested I've attained some kind of spiritual awareness, but I don't what to think about that. My theories are that 1) all events are either happening simultaneously, and we can only understand them in a certain sequence. Or 2) multiple timelines exist simultaneously and sometimes interconnect, but the mind is supposed to remember only one at a time. I just wish there was a way to test them.

@nathanwainwright0 Жыл бұрын

The issue I have with a lot of these explanations is that the argument we have for existence is that we were very “low entropy” (order) when matter was spread across the cosmos, but then things became more complex when “high entropy” (chaos) and the evenness became unevenness in planets and creatures. That chaos made things that were, by their very nature, more complex, but that level of complexity requires vast amounts of energy to maintain in a stable order (low entropy). Since things move from order to disorder (second law of thermodynamics), you have to have some unique situation where disorder becomes order, you need some force pushing back high entropy to create a low entropy environment. We know the 2nd law is still in effect as if we leave a complex being or machine to sit, it becomes less complex, eventually non-functional, and then eventually breaks down into its simplest molecules. So what introduced the low entropy system, what maintains it, and how long does it continue unless something invests in it?

@PixelZoft Жыл бұрын

The big mystery is that the arrow of time is the same everywhere and that it never ever changes. So time definitely has a direction. If you look at a pool table break on a video you can (with almost 100% perfect certainty) know the direction of time of the recording. No one needs to tell you. Ever. That you cannot tell from a small simple quantum physics event does not mean that it is not there. As soon as chance comes into play it can only go one way. So why is that? Because that is just how the universe works, in every single cubic cm of space we have ever looked at. I find that fascinating.

@Bobalicious Жыл бұрын

“Time is an illusion. Lunchtime doubly so.” ― Douglas Adams

@thebeezknees Жыл бұрын

Hammer time is real damn it.

@tayzonday Жыл бұрын

Also - with the expansion of spacetime - is the entropy of the universe REALLY increasing? Is the expansion itself a byproduct of increasing entropy? Perhaps space, as a medium, can only accommodate so much entropy per unit of “density” and expands elastically when more entropy is dumped into it?

@tylercriss6435 Жыл бұрын

Entropy isn't really a physical thing, like you can't hold a unit of entropy. It's just a way we describe arrangements of things that do exist, like atoms and the changes between their relative states of energy. In this case, maybe it would be less the entropy doing the expansion, but more likely the atoms or the energy. Maybe!

@ddv2nine722 Жыл бұрын

You could imagine the box at 3:38 to be expanding, meaning that the distance between balls is increasing but the relative distances staying constant. Since entropy really measure your failure to predict the state of the total system knowing a tiny part of it, then by this picture it should be constant (maybe), we should keep investigating.

@kaibuchan Жыл бұрын

I FEEL LIKE TAY ZONDAY, I FEEL LIKE TAY ZONDAY, I FEEL LIKE TAY ZONDAY, I FEEL LIKE TAY ZONDAY.

@wailinburnin Жыл бұрын

I'm pretty sure there's a property of mathematical symmetry that would say that you can view the universe as not expanding and "everything" in it is getting smaller and losing its ability to interact with everything else. It's just more convenient to talk in terms of us being the static things so therefore the thing that we're in appears to be expanding.

@MrSatnavatron Жыл бұрын

what about 'Stop engines' -- instead of speeding up - why not slow an object relative to the space time curve ? - multiplying the various speeds of galactic forces ( solar , galaxy , local group speed) we could travel much further than lightspeed if all those variables in "motion" are taken into account... cheers thanks -- send the Nobel prize to po box ....

@philjamieson5572 Жыл бұрын

He seems, to me, to make sense of things that have really puzzled me all my (very long) life. I am sincerely grateful that he's spent so much of his time and effort to do so.

@JonnyUnderrated Жыл бұрын

well im not sure he did it specifically for you Phil. But yeah it was cool.

@philjamieson5572 Жыл бұрын

@@JonnyUnderrated Yes. It was, as you stated in your well expressed, casual and throwaway style, 'cool'. I'm assuming that your comment was meant solely for me. I may be wrong with that assumption.

@JonnyUnderrated Жыл бұрын

@@philjamieson5572 Your casual utilization of commas has thrown me for a proverbial "loop" , Phil. I was trying to ingest your verbage and je ne sais quois but they took me off guard and now I'm all messed up. But yes, I was trying to communicate with you Phil.

@suhail_69 Жыл бұрын

@@JonnyUnderrated what are you both doing here 😃

@JonnyUnderrated Жыл бұрын

@@suhail_69 im trying to chill., our dear friend PHIL here is on some kind of diatribe again

@blanchsdp 10 ай бұрын

The steady increase in entropy, in addition to being beneficial as you point out, helps us keep track of cosmological time and explains a lot of the local features of time (aging, ice melting, etc.) That increase is something that takes place in time; not something that explains time. Suppose someone pokes a hole into a whole nuther Kosmos and the total entropy of this K begins to decrease as a result. We can speak of the time before and after this happened. Time's arrow survives.

@tayzonday Жыл бұрын

Time is different than causality, but we use them interchangeably.

@fullyawakened Жыл бұрын

@Mustachioed_Mollusk Жыл бұрын

@@fullyawakened possibly

@daz97 Жыл бұрын

The general population does that with everything, and as a result we live in a world of people who think they know everything about everything, because they spent a day learning about it on some random videos lol But because they simplified it so much it completely misses the point... If your foundations of study aren't done correctly then your end result will be wrong. Time, for me... Is just the measurement of motion But I'm not an expert in this area, and I never pretend that I am... Shame no one else these days can say that about any subject at all, everyone thinks they know everything because they read about it in Wikipedia lol Or because a Liberal college told them it so don't question it just obey lol

@ddv2nine722 Жыл бұрын

If you think on flat spacetime then they are not So different; for two events on the universe to be causal with each other, there Must be a difference on time, but you must also specify how far they are separated. So causality is a property shared by events with specific time And space separations. If light can connect those events, then they are causal.

@EonsEternity Жыл бұрын

@Daz this is basically what i find it to be as and when you really think about it the way we measure times with clocks the units of measurement are the tools themselves, the clock hands, and we based that off the sun, our rotations and revolutions around it and narrowed it down more but really we're just measuring change, we just measure the change of everything by using our constants for change, translating it like we translate imperial to metric, etc. How something so simple can also be so complex and amazing is just... amazing. I can't think of another word right now, but I just love the thought.

@deepaktripathi4417 Жыл бұрын

Thanks a lot for bringing such wonderful videos!

@DamnBoiya 21 күн бұрын

Entropy is my favourite concept in the course work I have completed, order to disorder. Always stuck with me too. Great video so far

@MusicPlaylistGuru Жыл бұрын

Sean is indeed articulate and helps us viewers understand a complex topic in layman terms. Would like to appreciate Big Think team's efforts in providing insightful KZfaq videos. I would request the team to also in simple terms shed a light on Newtonian Determinism versus Heisenberg's uncertainty principle. Thank you for your efforts.

@deadlinetrader Жыл бұрын

I just finished watching "The mind-bending physics of time" by Sean Carroll and I have to say, I really enjoyed his unique perspective on the subject. I found it fascinating how he was able to explain such a complex topic in a way that was easy to understand. I particularly liked how he delved into the concept of time being a "block" and how this theory can help to reconcile some of the discrepancies in our current understanding of physics. Overall, I thought it was a thought-provoking and enlightening video and I highly recommend it to anyone interested in the nature of time.

@Cosmo_P0litan Жыл бұрын

Someone had a school assignment... lol.

@MrFlameRad Жыл бұрын

100% a chatGPT comment lol

@bobbeckstead8340 Жыл бұрын

He "reconciled" nothing - you've been taken in by pseudoscience.

@Cosmo_P0litan Жыл бұрын

@@bobbeckstead8340 Prove your statement.

@bobbeckstead8340 Жыл бұрын

@@Cosmo_P0litan What an inane challenge.

@10sqrftthisthat Жыл бұрын

Unfortunately, the question of why we age has nothing to do with time but instead it’s a design issue.

@dennisgalvin2521 Жыл бұрын

Yeah, time is just a system that measures the process that makes us age.

@sixman9 Жыл бұрын

This is correct. Time is emergent and the measurement of the comparison of rates of change. Time is not an energy or force that asserts itself on objects. Milk does not got bad because 2 days have past, it is because of bacteria and heat energy, we are just able to expect a similar result, having previously seen a certain amount of days or hours pass under similar circumstances.

@bobbeckstead8340 Жыл бұрын

Thank you.

@bobbeckstead8340 Жыл бұрын

@@dennisgalvin2521 It measures the rate, NOT the process of aging.

@dennisgalvin2521 Жыл бұрын

@@bobbeckstead8340 To be specific, it measures he rate of the process.

@Exen88 Жыл бұрын

Sean’s got a great style of communication. I very much enjoy all of his talks. Every time.

@IOSALive 11 күн бұрын

Big Think, You're so talented! I had to hit the like button!

@TheSLK66 Жыл бұрын

“I know what it is, but when you ask me I don't.” Saint Augustine.

@dennisgalvin2521 Жыл бұрын

"I know what it is and when you ask me I still know" Bruce Dillon

@johnpetkos5686 Жыл бұрын

Sean Carroll is international treasure.

@rexxx4fun 3 ай бұрын

Daniel Schmachtenberger's talk on Emergence takes a crack at some of these questions.

@danielshults5243 9 ай бұрын

Sean Carroll is definitely one of the best science communicators around.

@michaelccopelandsr7120 Жыл бұрын

Time is fascinating. I worked the subway stations for nearly 10 years. From one end of the city to the other. Every so often I would notice the city would be saying that, "Today just flew by" or "The day was just dragging along." How can an entire city complain about the same time paradox unless it was effected by it. Maybe a time distorted bubble the earth passes through in its revolution around the sun. Maybe random waves of time distortion hitting the earth? Maybe they're randomly given off by the sun. Maybe they're from outside our Terran system and reach us in intervals. ???? Ti-i-i-ime, is on my side. Yes, it is!

@yan-amar Жыл бұрын

I would rather suspect a bias of confirmation on your part, I'm sorry. For one if time stretches, then our perception of time should stretch with it, shouldn't it ? Well, maybe not. But there are other factors to take into account. The whole city is subject to the same weather, it's the same day of the week for everybody (monday VS saturday, the mood differs). Plus city-wide, nation-wide events affecting the mood. All the people taking the subway at the same time, probably have a common lifestyle (working day jobs), they are linked socially. Etc.

@michaelccopelandsr7120 Жыл бұрын

@@yan-amar that's fine. You don't have to believe me. Great part of this is, this "phenomenon" is reoccurring. Just spend a year or two in the subway. Rush hours are best. Stopping at every station on the line. From students to working class to business class. You get to hear how an entire city's day went. After a year or two, you'll see it, too. The pattern in the chaos. ;-P

@simesaid Жыл бұрын

@@yan-amar while everything you say about social uniformity and cultural synchronicity is true, time _does_ stretch. Or to be precise, matter travelling through spacetime _shrinks._ But time itself does have elastic properties, beyond merely those of relative perception. As Einstein showed in special relativity, and as has been proven in every experiment ever conducted since the theory was published in 1905, how you move through space affects the way that time passes. Specifically, the faster one moves through space, the slower one moves through time. There is a very precise trade-off that occurs in order for the universe to maintain an upper-limit on the speed that matter can move through it - namely, 291,000,000 metres per second - the speed of light. Travelling at the speeds we do here on Earth the effect is almost unnoticeable, though for a few thousand dollars you can buy clocks accurate enough to see for yourself. At the speed that satellites orbit the Earth, around 27,000 Kph, the effect is strong enough that Google maps would be a useless app if the effects weren’t adjusted for. And should you travel out to Alpha Centauri at about half the speed of light before returning home to Earth again, you’d find that everyone back home had aged by about 40 years, while you had only aged 5. Einstein showed that time is personal, that there is no such thing as a universal time (as Newton had believed), and that it doesn’t even make sense to say that there is a “same” moment of time for any two objects in the universe. There’s a 5pm in NYC for you, but only you. Time is personal - the faster you move through space, the slower you move through time. Trippy, but absolutely true. Cheers!

@simesaid Жыл бұрын

@@yan-amar I should have added that the shrinking and expanding component is called ‘length contraction’, when travelling at relativistic speeds matter experiences time dilation (the slowing of time), and length contraction (where matter is ‘squashed’ in the direction of momentum. Again, here on Earth, and travelling at our speeds, the effect is completely imperceptible. Driving a car on the HWY for example, will reduce its total length by about the width of a proton… Yeah, I wouldn’t worry about that one too much either :/

@Whoisreading Жыл бұрын

I believe you. I'm far from your location, but I noticed the same thing, not in a subway but in live as a whole. I even got to name it, I call it "wave" or maybe a " low or high center of pressure" of some sort as in the atmosphere but of course not related to weather. I even avoided some corners or gas station because I "felt" as if a particular location "brings" a certain mood or even to happens. I though sometimes myself a bit superstitious for this but here you are talking about the same thing.

@thischickkej Жыл бұрын

He explained this wonderfully! Wow

@1776adb Жыл бұрын

Our use of time is all that is important.

@TheYorkshireVlogger Жыл бұрын

I had to watch it twice before my brain processed the information. I got there in the end. Thank you for another wonderful video. 😎

@StanCarles Жыл бұрын

Sean Carroll is a great teacher!

@JonnyUnderrated Жыл бұрын

Youre a good student Stan.

@brendangoosen Жыл бұрын

Time is our abstract explanation of change. It is our illusion.

@bobbeckstead8340 Жыл бұрын

More precisely, of motion - change is derivative of motion.

@Sam-we7zj 21 күн бұрын

@@bobbeckstead8340 no idea what motion without time means

@enchanted_swiftie Жыл бұрын

A man with this much interesting information can pass his all day talking with himself without a need of anyone.

@user-gj7vp6wk3e 22 күн бұрын

YOU ARE CORRECT ABOUT SPACE-TIME, PROFFESSOR SEAN CAROL. I, TOO, DON'T HAVE THE TIME TO WATCH THIS, OR DO ANYONE WHO MATTERS OR DO ANYTHING! PERIOD❤

@jayshomer4191 Жыл бұрын

Time is simply man made, as a unit of measurement. The eternal moment that has always existed and always will, is the brain twister !

@rasulsamad5860 Жыл бұрын

Well said my pops always told me that

@PaulJohn283 Жыл бұрын

It’s all been explained in the Bible you big dummy.

@ochjim Жыл бұрын

Yep. It doesn't exist, except as a manmade construct - a way of imposing order on events/action in order that we can make sense of it all and plan our lives . . But it is based on physical constants of atoms in order to be accurate, and therein lies the problem when we move too fast - near the speed of light, when the properties of atoms are so affected that the constants no longer apply/are changed.

@BenJehovah6969 Жыл бұрын

@Jim Hogg Not entirely true. It was conceived as a tool, but like any tool it could be used to build good and bad things.

@BenJehovah6969 Жыл бұрын

@Jim Hogg Not entirely true. It was conceived as a tool, but like any tool it could be used to build good and bad things.

@helifynoe9930 Жыл бұрын

It is better to explain "Motion", since Time is merely one of the four dimensions of the 4D Space-Time environment. As I have shown, by looking at motion in the 4D sense, it makes Special Relativity(SR) so easy to understand, or even discover it on your own, and allows you to derive the SR mathematical equations in mere minutes, despite knowing nothing at all about physics.

@StuartHallPlectic 10 ай бұрын

Enjoyed listening to this explanation of time and entropy that both started with the big bang. To state the obvious, both are also forms of organisation. 😊

@zuhaibkhan3694 Жыл бұрын

The intricacy of entropy renders the Newtonian world in abstraction. It’s a labyrinth. ❤

@RTL2L Жыл бұрын

Great video, thank you! Love it, when BT is about science, not agendas.

@bunklypeppz Жыл бұрын

I'm not convinced of his point in opposition to the notion that 'life' inherently fights against the increase of entropy. He makes a good point with regard to how the process of increasing entropy is not necessarily the enemy of living systems in every regard, but speaking specific to the processes within living biological systems, they almost exclusively strive to reduce entropy within themselves. If this were not the case, injuries, infections and even aging would not be detrimental, because there would be no reason to expect that their results would have a negative impact rather than a positive one. For example, head injuries would be as likely to make you smarter as they are to cause cognitive problems.

@ALLAH-0-AKBAR786 Жыл бұрын

Hi Mr Carroll hope you doing good You gave us the wonderful explanation about universal facts but not at all but I can help you out with rest of the answers that you asked in this video. Because knowledge has to be shared.

@apolloniustyana7372 Жыл бұрын

I wish I actually knew if reaching a state of maximum entropy would mean that there is no longer Mass and therefore no longer time but I am extremely impressed with Roger penrose's conformal cyclic cosmology theory it's very impressive the way he was able to think out of the box on this one I really like the conformal geometry part also I wish I was better qualified to like it even better or just say no this is wrong

@phm19880 5 ай бұрын

I hear you. I have been impressed of sir Penroses ccc theory. It just is impressive, and like u said out of the box thinking, challenging other scientists in a good way. Overall I have been fan of his thinking and I have watched some of his lectures from yt. You have a great taste 👍🏻😅

@DutchBoulders Жыл бұрын

Wow the clarity of his explanation makes every concept crystal clear! Thanks Sean

@JonnyUnderrated Жыл бұрын

so will you invest in shiney DIAMONDS or shiney GOLD Sir ?!??

@jamieaitch8969 Жыл бұрын

Loved this. Such a great presentation. :)

@ryanmccutcheon4198 Жыл бұрын

The entropy explanation makes sense until you think about the fact that we decrease entropy all the time in our daily lives and it has no effect on time, and certainly doesn’t reverse time. I like Richard Mueller’s theory from the book “Now: The Physics of Time.” Basically, his theory is that since spacetime is expanding, there is more time being created and we are always right on the edge between past and future and experiencing the new time every second that passes by.

@wtfserpico Жыл бұрын

That is far more satisfying. I feel like he kind of lost the plot so to speak in his explanation here, and I kept waiting for him to bring it back around and then the video was over.

@rohanjagdale97 Жыл бұрын

Time exists in our brain

@kurtsydavis7517 Жыл бұрын

Where our brain exist?

@bobbeckstead8340 Жыл бұрын

Bingo! All of our daily experience exists in our minds. Only rigorous science can show us some of the approximations of reality that is independent of our minds

@mmmmemems4068 Жыл бұрын

It’s interesting that our point of view is time and entropy moving in opposing directions but they’re actually moving in the same direction.

@Slo-ryde Жыл бұрын

Entropy serves as the barrier that ensures that we can never travel back in time!

@Hybrid869 Жыл бұрын

He brings up a lotta good points around Time but it makes me feel like there's enough open questions to keep "What is Time?" on the table.

@okgroomer1966 Жыл бұрын

It never left the table. We discuss theories on such topics, not facts.

@RobRoss 2 ай бұрын

I think Time is the same kind of philosophical issue as Free Will. In the case of Free Will, most philosophers tell us it doesn’t work the way we think it works. But Time and Free Will are both human experiences, regardless of the underlying mechanism. When people say “there is no Free Will,” what they really mean is that your idea of what Free Will is isn’t actually how it works in the Universe (see Compatibleism for an idea of how it might actually work.) Similarly, even if Time is emergent and not fundamental, we still have this experience we call Time. If you are Julian Barbour and believe that “time doesn’t exist,” well the fact that “things change” is how we subjectively experience “Time,” whether or not the underlying physics is different from our intuition.

@batouttahell454 25 күн бұрын

I wish you spoke more about free will!

@TheHonestPeanut Жыл бұрын

I love when people sidestep questions by saying the question isn't the question lol

@shanezanath2092 Жыл бұрын

I read Carroll's book From Eternity to Here, which I highly recommend. However, I'll admit I'm slightly confused by his overarching and unanswered questions: Why is entropy increasing towards the future and not towards the past? And if the answer to that question is the big bang, why was the big bang at a state of such low entropy? There is an episode of PBS Spacetime that potentially explains this (as I understand it, at least) as the volume of Spacetime itself actually increasing, and this gives rise to increasing entropy and the arrow of time. I wish I could see Carroll debate this point, or other physicists weigh in!

@1viewer1 5 ай бұрын

Absolutely beautiful explanation. So when an object is able to escape the gravity of our giant vicinity toward another celestial sector with weak gravity (to do more,get old faster) or stronger gravity (to do less,stay as same age longer), that’s how time travel work, ie. Being away to deep space and missing out, either for long or short duration) of the time of those left behind in earth.

@doggygaming950 Жыл бұрын

Understand that all moments in time past and present exist simultaneously and forever. Our perception of time moving forward is a function of our memory with the most recent being the strongest and the ones in front or us forgotten completely. It would be easy to code in a way that no matter where you are in time you would perceive it as the present.

@Salted_Potato Жыл бұрын

Probably the best explanation of time i have seen in a video, amazing explanation from Sean and thank you Big Think for the illustration and platform

@ochjim Жыл бұрын

Except that he didn't actually explain what time is . . .

@jesusbermudez6775 11 ай бұрын

@@ochjim Yes, he went on to talk about entropy and brush aside time

@DoubleplusUngoodthinkful Жыл бұрын

I see time as having 3 dimensions like space does. In fact, I believe it's really just another 3 dimensions of space. People think that you go forward and theoretically backward in time. I believe that moving through space makes you move through time. The changes we make in space change our direction in time. You're not going linearly forward through time as much as steering through it, like driving a car. When you turn your steering wheel in a car, you turn left or right in space, but you do the same in time. If you went "back in time" and turned left, you would see events that, to your perception, never happened, just as if you turned your car around and went back the way you came, but then turned onto a side street you did not traverse before, you would see things there that you didn't see before. If you stop completely in space, you might very well stop completely in time. We don't know how to stop in space, however, as we can only use bodies in space for reference, all of which are moving in an unknown absolute direction. We know what speed we are moving relative to the object on this planet around us. We know how fast our planet is moving relative to the sun and other planets. We know how fast our sun is moving relative to our galaxy. And we know how fast our galaxy is moving relative to other galaxies. But we don't know in what direction this whole swirl of activity of all of the galaxies collectively is ACTUALLY moving, or how fast. So while time might seem to be on autopilot, it is only as much as objects moving through space.

@mkaufmandev Жыл бұрын

The dropped coffee cup is something Stephen Hawking talks about in 'A Brief History of Time'. He says time travel to the past is not possible precisely because when we drop a cup it shatters into many pieces. We NEVER see it go back together in reverse. This was Hawking's analogy.

@bred3862 Жыл бұрын

Is there any equations which state relation between time and entropy

@DaveBuildsThings Жыл бұрын

Time and entropy are the same thing. The increasing entropy of our universe means there is change. With change, there is time. When nothing in the universe changes because we at the highest entropy possible, then time will cease to exist. Without change, time is not possible.

@bred3862 Жыл бұрын

@@DaveBuildsThings i don't think so bro as time is relative but entropy is not(maybe)

@justicecarr7261 Жыл бұрын

I have a serious question: was it, or is it possible to change the human ability to stay awake and how long they sleep? Think about it, if billions of years ago you, stayed up for 3 days and than slept for let’s say 27 hours and kept repeating it over and over, would that have changed the way we sleep or count or days now? Or was it always perfect. Also lmk if this is already explained somewhere, cuz this is just right off the top of my head. And if this is possible, could we go for even longer periods of time awake?

@CraigMCox Жыл бұрын

Our internal clocks are tuned to the earth’s rotation. If we lived on a planet with a 54 hour rotation, maybe we would sleep for 27 hours

@justicecarr7261 Жыл бұрын

@@CraigMCox that’s crazy to think about tbh. It’s just crazy to me that we just “ended up here” on this planet 3 billions years ago, or around there. Im just so curious and intrigued about our existence it’s hard not to think about that stuff.

@sanguinetenetsofnull9227 Жыл бұрын

I heard that in ancient times we did sleep twice for like 3 to 4 hours. Butt have to verify how true this is. But there's biology.. our health. If we don't get oxygen we will die within minutes. Similarly sleep, we won't die in minutes but we will definitely degrade and eventually die. Every body is different and everyone's sufficient sleep hours differ. Some need 6hours some need 8. There's even talk about being sleep deprived can result in brain condition that's more bad than post alcohol consumption. So don't skip sleep and drive.

@sanguinetenetsofnull9227 Жыл бұрын

And there is survival of the fittest concept as well. On earth atleast people with current sleeping habits or genes seem to have survived.

@chadwillett619 Жыл бұрын

With drugs I have gone 9 days with no sleep, on day 9 drugs didn't work anymore and I crashed out for couple days.

@donniedavis6163 Жыл бұрын

Time is just something that allows things to happen. Simply put...if time didn't happen, nothing could happen at all

@bosun99uk Ай бұрын

Thank you for your Time 😊

@kevinjenkins6986 Жыл бұрын

I love listening to brilliant physicists dumb stuff down for us, that in and of itself is an amazing feat 👍

@philjamieson5572 Жыл бұрын

Kevin Jenkins: Excellent comment. Well said.

@Diponty Жыл бұрын

I love bots.

@coolaa7 Жыл бұрын

Is this video mislabeled or am I just that much of an idiot?:) I definitely missed the part about "The mind-bending physics of time."

@peterdamen2161 Жыл бұрын

Exactly what I thought, and commented about. Carroll says around 1:21 min that what time is, is not a question. But he doesn't explain what time is. So I can only deduce that he dosn't know what time is.....

@freebk161 10 ай бұрын

Perfume in a bottle 👍👍👍. The complex concept described in one line. Thank you Sean 😊

@nikolayastashkin4834 Жыл бұрын

Time is the word we use to denote the number of events that repeat, such as the rotation of the sun around the earth, or the hands of a clock, or any other repeating event. Time is not a certain substance, not something that flows somewhere. Past, present and future - do not exist except in our imagination. What exists is a stream of change. The concepts of time, present, past, etc. - these are words for coordinating the interaction of people with each other, nothing more.

@abrahammulder Жыл бұрын

So very very true! Time is an Illussion!!

@dennisgalvin2521 Жыл бұрын

A very nice brief explanation.

@GeorgeSmiley77 Жыл бұрын

Time is what stops everything from happening all at once. Space is what stops it from all happening to me.

@safebox36 Жыл бұрын

I'd have said there _is_ a special direction of space, it's just more scalar than vector. There is a limit to how small something can get before it effectively can't "be". Quantum mechanics operates on all scales, it's just that the more of something there is the more variables come into play. But as you measure smaller and smaller, eventually you hit a limit where no quantum wave can possibly exit without be needing to be divided; which by definition of "quantum" cannot be done.

@ArpanD Жыл бұрын

This is probably the best explanation of the arrow of time I've ever seen

@rum-ham Жыл бұрын

This video explained almost nothing. He simply restates simple concepts in a way that makes it sounds insightful. Reminds me of The Onions "Onion Talks" videos.

@idahospud6979 Жыл бұрын

WOW! I actually understood what he was trying to explain!

@piyushjoshii Жыл бұрын

Learnt a new word today : Entropy! Thanks. I’ll try and use it now.

@satanofficial3902 Жыл бұрын

"Time is timely because it's timed with timeliness." ---Albert Einstein

@satanofficial3902 Жыл бұрын

"Space is spacey because it's spaced with spaciness." ---Albert Einstein

@satanofficial3902 Жыл бұрын

"I see dead people." ---Albert Einstein

@dennisgalvin2521 Жыл бұрын

"Time is the rime time takes time to time time". Dennis de jong.

@jimbonacum8917 Жыл бұрын

I can't recall who said it but the reason we have time is because without it everything would happen all at once.

@sumit06pattnaik Жыл бұрын

Beautifully explained. Loved it

@aminnima6145 Жыл бұрын

Just love this explanations ❤️

@bobbeckstead8340 Жыл бұрын

There are no "explanations" of time - you've been conned by a good performance.

@grapes9h5 Жыл бұрын

Love this. Reminds me of why I enjoyed the movie Tenet so much.

@JustUnjust Жыл бұрын

This conversation shifted from time to entropy.

@garygevisser1262 Жыл бұрын

Total nonsense in my book. I see no relation between time and entropy. Best example of mixing apples and oranges but at least with apples and oranges you can eat them without turning your brain to mush unless that have been poisoned.

@kj475 Ай бұрын

We do have the ability to affect our past. The decisions we make today and in the future will have an effect on our future past. 2 years ago I had the ability to impact the events that occured 1 year ago.

@JasonFolkerts Жыл бұрын

It's amazing to me that many physicists refuse to acknowledge there could be a designer outside of the bounds of the universe who is conducting all things. Call that force god or whatever identifier you like. However, there seems to be evidence everywhere given the characteristics of the universe mysteriously finely-tuned to enable human life.

@platinumpineapple9943 17 күн бұрын

Our brains can actually speed up time and slow down time depending on whether we are bored or sick or in harm. vs when we are occupied, having fun, relaxing, etc.

@TempPlacement 5 ай бұрын

The best thing I discovered in 2023 was Mindscape! Thanks!

@bokchoiman Жыл бұрын

I think time seems to slow down when you're engaged in transformative activities. The constant changes in your environment fill your time with memorable moments, making you feel like you've actually made good use of your time. When nothing changes in your life, the relative change between one moment to another is small, and so your time speeds up. You've few moments to look back on and it feels like you've wasted your time.

@twotubefamily9323 Жыл бұрын

That's how individuals experience time - no relationship with space/ time whatsoever

@bokchoiman Жыл бұрын

@@twotubefamily9323 Notice i wrote "seems"

@moicao4568 Жыл бұрын

Truly mind-bending ! After watching this, I'm a little more confused than I already am. Sticking with Earth Time , I guess...

@keything8487 Жыл бұрын

very good explanation....thank you

@ronaldleedham4719 Жыл бұрын

Thank you for this thought-provoking topic.

@darrinwebber4077 Жыл бұрын

I believe "time" is just our perception of the expansion of space. Always forward

@stevenhawk7626 Күн бұрын

Well put dude.

@linfan6596 11 ай бұрын

"The answer to the question of what time actually is, is still not apparent here. Time is defined as the sequence or collection of events, but what exactly is an 'event'? If everything is made of matter and by that made of energy, and there is a fundamental relation between time and energy. Then this same relation holds universally as long time and energy are related. What I propose, in this comment section, is that time and energy are not two separate physical quantities but are in fact interdependent. Time is the change of Energy. A change in the energy of a system, Entropy, is what registers as an event and that event registers as time." - Keyboard Physicist

@TucciHair7896 Жыл бұрын

First thank you for such an elegant mind-bend! Can you please 🙏🏾 pass on the information about the apparatus holding your backdrop paper.

@sunroad7228 Жыл бұрын

The Arrow of Energy: "In any system of energy, Control is what consumes energy the most. No energy store holds enough energy to extract an amount of energy equal to the total energy it stores. No system of energy can deliver sum useful energy in excess of the total energy put into constructing it. This universal truth applies to all systems. Energy, like time, flows from past to future".