Space-Time Versus the Quantum

UCSB’s Joseph Polchinski speaks about the search for a unified theory of the laws of physics, and the difficulty of reconciling two of the main pieces: quantum mechanics, which governs the very small, and general relativity, which governs the very large. A professor of physics and a permanent member of the Kavli Institute for Theoretical Physics, Polchinski was named UC Santa Barbara’s 2014 Faculty Research Lecturer. Recorded on 12.04.2014. [11/2015] [Show ID: 30118]
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Пікірлер: 116

  • @KipIngram
    @KipIngram3 жыл бұрын

    40:45 - Maybe the information never goes in. Maybe it gets painted on the horizon when stuff falls in. This actually kind of makes sense - if you're watching an object fall into the black hole, gravitational time dilation slows down the object's time. As it approaches the horizon, it moves more and more slowly, and actually you NEVER SEE IT FALL IN. It just asymptotically approaches the horizon. So from that point of view the information just bundles itself up at the horizon from the get-go.

  • @shirleymason7697
    @shirleymason76977 жыл бұрын

    Pleased to hear this summary, presented differently from all the others I've watched. As a totally non-physicist I pick up a new idea with each lecture. Thank you.

  • @huckleberry6650
    @huckleberry66506 жыл бұрын

    starts at 5:30

  • @Catman7442
    @Catman74426 жыл бұрын

    I wish they dimmed the lights so I could see the slides easily or insert them in while editing as soon as he starts describing the next slide (each is much too brief, as is). Good lecture.

  • @Moronvideos1940

    @Moronvideos1940

    6 жыл бұрын

    You are asking Dorks to think in practical terms Never works

  • @TubeYouJet
    @TubeYouJet5 жыл бұрын

    Good presentation, but I wish the camera person would have focused more on the slides instead of the professor holding the microphone while he stared up at the slide to which he is talking about. If we were in the audience we would focus on the slide as the professor would direct our attention.

  • @josephwanderingspirit739
    @josephwanderingspirit7392 жыл бұрын

    Lecture starts at 6:00

  • @dankkiller1
    @dankkiller17 жыл бұрын

    Black holes Dark energy and Dark matter are some how linked and could be written as a ratio as mass of the black hole * Dark matter* Dark energy. The matter that falls into a black hole I think it is projected outwards as Black body radiation, dark matter or you could think of a black hole shines in gravity, and gravity is just a extension of the electro- magnetic scale. I think that Boltzmann transport equation applies here. This I think would go along way in explaining the unified field theory. ( 4% V +23% DM +73% DE ) Make up gravity as a whole. After space time and matter fall into a black hole I think it goes through a phase transition. Einstein spoke of anti-gravity (Dark Energy).

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    Attention under-informed and unwary readers: KZread *Crackpot Alert* ❗ 😏

  • @mlb7583

    @mlb7583

    Жыл бұрын

    @@frederickj.7702 Your mom

  • @Dyslexic-Artist-Theory-on-Time
    @Dyslexic-Artist-Theory-on-Time6 жыл бұрын

    Good info!!!

  • @martin36369
    @martin363698 жыл бұрын

    Isn't the Firewall Entangled with the Particle Pair?

  • @Aluminata
    @Aluminata8 жыл бұрын

    Why should a black hole necessarily contain a singularity point of infinite density - an accreting neutron star may be on the cusp of becoming a black hole as its gravity approaches the escape velocity of light - it is still a ball 10 miles in diameter...The additional inflow of mass will eventually tip it past the point of gravity that exceeds the escape velocity of light - it is now a black hole. Will is go from super dense object 10 miles in diameter with the addition of the final kilo which tips it past the point where light can escape, into some infinitely dense, infinitely small singularity? At what point will it stop allowing light out and what will happen as this point is exceed by a milligram - will it instantly go black - or will there be a hiatus period of dimming?

  • @3877michael

    @3877michael

    8 жыл бұрын

    +Ralph Latham Black holes are a hallucination. They only exist as a mathematical model based on a hallucination. Black holes with mass do not exist. They are void of matter but filled with electric current and magnetic field. So all power and no mass. This why they can not see a black hole. But they can measure it’s magnetic fields.

  • @frederickj.3792

    @frederickj.3792

    7 жыл бұрын

    +3877michael... Sounds like you've been to one and 'inspected the landscape'... on a busman's vacation from your usual psychological home territory on mars.

  • @3877michael

    @3877michael

    7 жыл бұрын

    Frederick J. Yep Oh and by the way the earth really is round... Flat earth people have never been in space or out of their body. Is sad really people who are so bound by beliefs.. You do know that Steven Hawking has given up on Black Holes right. He had a long standing debate with Dr Rudy Schild out of Harvard . So Rudy won the debate and is the current world authority on Black Holes.. He had to rename them.. They are now MECO’s Magnetic Eternally Collapsing Object . Go figure an eternally collapsing magnetic field.. Who would have thought? I could probably get his e-mail if I had the need . He is on the board of directors of this organization I am a member of.... Dr Edgar Mitchell was the head of the board but he has recently died..

  • @shirleymason7697

    @shirleymason7697

    7 жыл бұрын

    Ralph Latham ....you need to really listen again.

  • @glutinousmaximus

    @glutinousmaximus

    6 жыл бұрын

    Well, no. Black holes are created by very large events involving enormous amounts of mass. We know that two colliding neutron stars _might_ produce a black hole; but you must remember that a lot of mass is lost in 'gravitational waves' - energy given off as the bodies coalesce. We also know that most observable galaxies have massive black holes at their centers, and appear to be instrumental in the creation of galaxies as a whole. A 'milligram' of matter would not be sufficient to make the transition, since Hawking radiation would almost immediately use up such a tiny mass. Learn physics and impress your friends! :0)

  • @quantumcat7673
    @quantumcat76734 жыл бұрын

    The entropy is constantly growing in the Universe from a beginning that had low entropy. If there was a "big crush" prior to the big bang, would that have lowered the entropy of the universe?

  • @quantumcat7673

    @quantumcat7673

    4 жыл бұрын

    @NotACapitalist Sir, are you on drugs?

  • @quantumcat7673

    @quantumcat7673

    4 жыл бұрын

    Sir, you are entitled to your own opinion. That said, whatever opinion I did express to you in a few lines do not reflect in general the conclusion I would have if I had reviewed all the pertinent material about the subject. However, I sure can't fail to see the heavy emotions attached to many of your words as if you've taken my words in a personal way. Just don't take me too seriously for I do not even take myself too seriously. I am obviously quite aware of my inherent human condition and the limits associated to it.

  • @glutinousmaximus
    @glutinousmaximus6 жыл бұрын

    Perhaps this should be better titled: "Space-Time _AND_ the Quantum". Both theories are extremely accurate and well-established, - both theories have stood the test of time; Relativity in the 'new' field of gravitational waves.

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    @ Adam Mangler... Sorry, mate, you completely missed the point of what the firewall hypothesis means as part of the black hole Information *paradox* . Try watching again (pause and read the 'slides'), or seek more information elsewhere if you are sufficiently interested.

  • @crazieeez
    @crazieeez6 жыл бұрын

    He passed away at the age of 63. *sad*

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    A very great loss, crazieeez. Dr. Polchinski was in a very elite class among theoretical physicists (elite on the basis of merit, that is).

  • @TheBabaG
    @TheBabaG5 жыл бұрын

    Gravity is acting towards the center of the any star. Large mass, large gravity towards the center of the object. But why space time bends outward direction near the edge of the heavy star? This Confused me

  • @onhuevokrem3129
    @onhuevokrem31295 жыл бұрын

    For me personally there are so many unanswered questions.For example what the end of a black hole looks like - is the information that comes out 'new' in terms of not existing particles in our universe.I mean what I could know is that our universe might have been a black hole and when the end of the black hole come it exploded forming a while while and the big bang and out universe with this particles 'we' have right now ... I mean in minute 35:53 there it says : " information lost information escapes - how about Information comes in and changes it self to something new - for example not electrons but into some new particles then goes out now transformed - it reminds me of the saying : What happens when unstoppable force meats unmoving object - for me what happens is think about the unstoppable force as wind and the unmovable object as mountain - ofc when wind blows it doesn't move the mountain but in order of the saying to be true that mean that the wind transforms the mountain into wind or the energy is transformed - the mountain ( the unmovable object didn't move) didn't move and the wind (unstoppable force) didn't stop it just changes.Same goes about here - what if the energy that 'comes out' of black hole after the end of the black hole 'life' is new big bang that creates a universe just like ours at different time speed for example or completely new universe with new rules of particles or new physics laws.Or universe that runs backwards in time.Basically what I'm trying to say is what if you trow the number 1 into a black hole and comes with the same meaning but number 1 as a symbol is number 2 or # or the point i'm trying to make is number 1 the same ? It might have same meaning but since it is not the same symbol does it really the same ? THE POINT IS .... what if the big bag of our universe was an end of black hole in some different 'previous' universe ... I don't know to be honest I don't understand physics ... gonna listen to some music since that makes me relaxed and eases my mind ...

  • @onhuevokrem3129

    @onhuevokrem3129

    5 жыл бұрын

    For example a universe where the speed of light is still speed of light but it is faster than our universe like instead of 299 792 458 m / s it is 299 792 459 m / s if you compare anything in that universe massless particles with move with max speed of light of 299 792 459 m / s not with 299 792 458 m/s ... the point is that there is so much possibility that is not denied by anything in our universe yet when we think about all the possibility there is only one possibility happens per frame time ... for example i might be right now doing dishes - washing dishes but here i'm watching video and typing comment and here you are reading my comment when you could not be using electronic device but doing something else with your life .. think about that ... what collapses the universe possibility's into one is is ... is it human choice ? or Choice in general ... dem this remind of the Bible some how ... anyways ... I should not think and mix physics with the bible :D

  • @blindbrick
    @blindbrick6 жыл бұрын

    27:39 That's an unflattering coincidence. Pour mister Hawking.

  • @martin36369
    @martin363698 жыл бұрын

    Does "Quantum" have to only mean "The very small", can't the term also apply to "The Unobserved"?

  • @martin36369

    @martin36369

    8 жыл бұрын

    +Steve Bergman Thanks Steve, but are you saying that "Quantum" can be applied to the not-small, as there are interactions going on with electromagnetism, certainly at small scales, but also at larger scales behind my back & unobserved.Also if Wheeler et al have formulated a quantum wave function for the Universe doesn't that include the Space-time of the Universe as well?

  • @Sam_on_YouTube

    @Sam_on_YouTube

    7 жыл бұрын

    The term comes from the idea of something being descreet, rather than smooth. Among the early uses of the term (though not the first) was in Einstein's paper on the photoelectric effect in 1905. That's the paper for which he won the Nobel prize, but only the 3rd most important of his 5 major papers that year, the other two being special relativity and E=mc^2 (which is a consequence of special relativity). In the photoelectric effect paper, Einstein realized that light moves in descreet packets of energy, quantizations of their waves, which are particles called photons. The quantizationof of the wave allows it to still be a wave, but also a particle. That's the fundamental idea of quantum mechanics and gives you a good idea of what "quantum" means. So when people look for a quantum theory of gravity, strictly speaking, they are searching for a way to describe the gravitational field and gravitational waves that allows descreet excitations called "gravitons" but still produces all the well tested results of General Relativity.

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    @ Martin Smith... The whole of the universe is probably quantum in nature, including the collection of atoms that make up 'you' -- that is what the quantum wave function, which applies to successive 'states' of the universe itself *as a whole* seems to say. To add a note to Steve Bergman's response and to answer your second question: spacetime itself does *not* have to consist of "atoms of spacetime". That is a naïve assumption which is easy to take away as an inference. Even some actions in solid state physics -- e.g., a certain type of "surface phonon" -- are described as continuous and not as discreetly parsed phenomena. Second, you're probable better off thinking of spacetime as *within* the universe, rather than the other way around. Or, from quantum field theory, that the fundamental element of everything in the universe is "space", with the quantum fields and their appearance as "particles" being inextricable components of that "space" (after Frank Wilczek).

  • @gerardopc1
    @gerardopc1 Жыл бұрын

    May he rest in peace

  • @bigMACDavey
    @bigMACDavey6 жыл бұрын

    He suggests that Einstein's remark, that the position of the electron isn't random, is incorrect as proven by our present inability to determine the location of the electron??

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    @ Perseus... Einstein understood quantum measurement and how the Born rule works better than anyone. Your suggestion is basically nonsense (sorry) and, I hope, simply a fundamental misapprehension on several levels.

  • @rovosher8708
    @rovosher8708 Жыл бұрын

    Hawking’s radiation does not emerge from the interior of a black hole (BH) but from quantum fluctuations at the horizon. This deems the BH & spacetime (ST) a pair of non isolated systems. Why then should physics expect the mutual coexistence of a BH & ST to conserve any quantity? Another argument which is usually levelled against general relativity (GR) is that a BH breaks quantum entanglement between a pair of entangled particles. Why is this a problem of GR? GR break the entanglement of a pair of photons (otherwise entangled in their helicities) by redshifting their momenta. The equivalence principle states that GR does not involve spin or helicity so the breakdown of an entangled pair of particles in their spin is a quantum mechanical (QM) problem, not GR’s. Regarding the singularity problem. GR implies gravitational waves (GW) which could interfere and deem the resolution of a singular point impossible just as it happens with EM waves. In summary, we do observe the bending and dragging of ST, BH & GW, phenomena predicted by GR, and there is no credible evidence that QM poses a problem with the theory. What if the problem really is with QM, i.e. it being incomplete?

  • @maff5002
    @maff50025 жыл бұрын

    Its all about spirals

  • @MiteranPasku
    @MiteranPasku4 жыл бұрын

    my intuition is that must be something wrong about quantum entangelment. It is a wrong interpretation that is making people spend their imagination . It is a real view point that two particles side by side would have a sincronization and if we devide this two particles in destance they still would be sincronized because of the logic they just being in ecuilibrated contineum and not because of not having any relation. it is like the logic of twe sincronized clock that they would tell the same clock because no body or no force is trying to change any of the clocks.

  • @rkpetry
    @rkpetry8 жыл бұрын

    The J term is redundant-only displacement as each electron approaches, passes, recedes.

  • @Gunnon1
    @Gunnon17 жыл бұрын

    We cant make simple audio working and we think quantum physics.

  • @KibyNykraft

    @KibyNykraft

    7 жыл бұрын

    Nowhere near the idiocy of too loud "background" music overruling the voice , or machine voice for long videos... So this one is fine relatively speaking.

  • @KipIngram
    @KipIngram3 жыл бұрын

    17:15 - "The noise." What a terrible description of what that inset graph represented. I'm un-impressed.

  • @idofgc
    @idofgc6 жыл бұрын

    It's too long and is slow

  • @frontech3271
    @frontech3271 Жыл бұрын

    How to enter a flat hole? "Road-Runner (and Wile E.C.)" theory. How does one perceive three dimensions in an animated cartoon? Or anything else for that matter. Everything in constant motion, induced by Time. Time is everything happening at once. Space keeps everything from happening all at once. Time density. Hahahahahaha, "I'm your density".

  • @pantep1728
    @pantep17286 жыл бұрын

    if there is no time, it is just the result of Entropy.

  • @MrVaypour

    @MrVaypour

    6 жыл бұрын

    Entropy is found everywhere except at absolute zero.

  • @rkpetry
    @rkpetry8 жыл бұрын

    Consider for example the 'thinkabit' I presented to Prof. S... at the UH Manoa Physics Open House this morning (Sat. 11/21)-his topic was The Einstein Light Clock... so, I pointed-out that if you accelerate an Einstein Light Clock gradually up to 1 mph, a billionth the speed of light, it breaks because the side-to-side (aka 'up-down') crossing photon slips out the rear... Or-if you close-up the mirrors the crossing photon loses orthogonality by bouncing zigzag fore-and-aft... his current college text shows the clock 'repaired' by restarting every photon. *ADD IT UP, kiddies: it's an 'Oersted Moment-!' All physicists do slight-approximationing...*

  • @MrRipplefix
    @MrRipplefix5 жыл бұрын

    A black hole seems to me as if its a tornado in space but instead of wind currents it's made of energy currents.

  • @frederickj.7702

    @frederickj.7702

    4 жыл бұрын

    And then there are the correct explanations... But getting serious, you *could* describe the *accretion disc* around a black hole -- or a rotating black hole *system* -- well enough that way, Thomas. Check out the Minute Physics episode here on the extraordinary and mind-blowing *efficiency* with which a black hole can convert mass and its gravitational field into radiating energy in another or greatly augmented form. Hydrogen bombs and stars can't compete.

  • @muskyelondragon
    @muskyelondragon4 жыл бұрын

    Farewell Joe 💘

  • @vinceypma8962
    @vinceypma89622 жыл бұрын

    The climate is in a persistent state of change.

  • @daxxonjabiru428
    @daxxonjabiru4288 жыл бұрын

    And indeed he did take questions all night. The end ...

  • @paulpietschinski3282

    @paulpietschinski3282

    7 жыл бұрын

    Daxxon Jabiru He also had his pick of ladies in the crowd after, he probed their black holes.

  • @carnsoaks1
    @carnsoaks16 жыл бұрын

    all points @ the horizon are coincidental, whatever was there @ time of BH collapse, is pinched off. any changes to the S/T that existed there once is now distinct, a new cosmos. The inflow of light / matter, changed such that Space is concentric rings all the way down the rabbit hole, and TIME becomes the direction, ie arrow of time begins again. that is where the time like direction only drives in one direction eg CPT symmetry lost

  • @petechandanatural
    @petechandanatural7 жыл бұрын

    look up Nassim Haramein the Holographic Fractal Universe and how he predicted the proton radius using the plank unit sphere units and sacred geometry

  • @petechandanatural

    @petechandanatural

    7 жыл бұрын

    Well,,,,.that has changed with his paper on the proton radius. There is pdf file. The old ones die off eventuality.

  • @ADD7DJ
    @ADD7DJ7 жыл бұрын

    Drifted onto reading from other open tabs and couldn't help but notice... Remarkably similar to Kermit the Frog...

  • @KidEatingClown

    @KidEatingClown

    7 жыл бұрын

    Kermit mixed with Ray Romano.

  • @ADD7DJ

    @ADD7DJ

    7 жыл бұрын

    KidEatingClown spot on!

  • @shirleymason7697

    @shirleymason7697

    7 жыл бұрын

    Then you shouldn't bother. Go play marbles or something simple that can hold your interest.

  • @mariemartin4371

    @mariemartin4371

    3 жыл бұрын

    Km

  • @GUPTAYOGENDRA
    @GUPTAYOGENDRA6 жыл бұрын

    General relativity and quantum mechanics forces us to believe that Consciousness which is Singular and Fundamental is observing the universe without mind.

  • @salihkrcalar9230

    @salihkrcalar9230

    5 жыл бұрын

    John David Best has his web site Vida İnstitute. He put my articles page in 'Timeflow Theory' 'vidainstitute.org/?page_id=656'. Vida Institute is intersting site. And my web site is www.timeflow.org In your opinion, discovery of a planet is more exciting. Or, as I've presented in the attached article, whether observing 'A very tiniest mass in the space, having completed its life, have been turning into energy' would be more exciting or not ? It is my belief that, this observation will be the proof of the General and the Special Theory of Relativity. This observation can be made only by NASA or ESA. I hope that I will be able to see this consequence while I'm still alive.

  • @pierretruchon6523
    @pierretruchon65236 жыл бұрын

    I believe in the mighty big black hole that that created us and is now trying to reabsorb his creation before other gods get aware of it.

  • @bobbyghost2594
    @bobbyghost25945 жыл бұрын

    The answer to everything is Infinity.. Universe? Infinity, time? Infinity, black hole? Infinity.. God? Infinity

  • @Eric06410
    @Eric06410 Жыл бұрын

    Space-time is doomed

  • @Utsusemi
    @Utsusemi6 жыл бұрын

    dry humor

  • @3877michael
    @3877michael8 жыл бұрын

    Space time is a joke. It is like if you called a tree, Tree Time. Or a dog, Dog Time. The tree or the dog or space have nothing to do with time. Time is a measurement of movement or change imposed by the observer.

  • @3877michael

    @3877michael

    8 жыл бұрын

    ***** Nobody can because it is hallucination of Michelson-Morley that they gave mathematical value too. 4 dimensions or 7 dimensions or 11 dimensions are still hallucinations first before they are given mathematical certainty. And you say I am nonsensical ? Most of science is nonsensical. Imaginary inflation and pretend expansion and cartoon strings get ridiculous at some point. 4 black hole universe models and three big bang models and a few assorted big crunch models of what is observed. Crack me up. But every model fits mathaOmagically and no hallucinating is involved at all. Each camp is absolutely certain. Senses are touch and taste and so on. Observation of the real. And we have a sixth sense that uses imagination. This observing with the imagination is not using your five senses it is using non-sense and so ingrained into science is this that the idea of using your five senses is considered nonsensical. Yes? Good job..

  • @3877michael

    @3877michael

    8 жыл бұрын

    And yet you are.. Good for you.. Time is psychological time. It is in the mind. I am so glad you know everything and it is proven. And light bends by many things. Gravity is at the bottom of the list. Density of the medium is at the top. Well you have an effective dream world and so effective you cannot tell waking from dreaming so good job.

  • @dangiscongrataway2365

    @dangiscongrataway2365

    8 жыл бұрын

    +3877michael I see someone here had bad grades in special relativity...

  • @rljpdx

    @rljpdx

    8 жыл бұрын

    wow, you're dumb

  • @septicwomb4394

    @septicwomb4394

    7 жыл бұрын

    how did someone with this level of ignorance on relativity even end up on this page.

  • @CowboyStag
    @CowboyStag5 жыл бұрын

    In in in in in So so But but So so so so so Are are The the the the I’ll I’ll I’ll Jesus Christ

  • @irishrepub84
    @irishrepub844 жыл бұрын

    quantum embarrassment

  • @CowboyStag
    @CowboyStag5 жыл бұрын

    In in in in in So so But but So so so so so Are are I’ll I’ll I’ll Jesus Christ

  • @dentonfender8872

    @dentonfender8872

    5 жыл бұрын

    You better hurry to that mountain top. You are going to miss him when he comes to take you away---Jesus H. Christ