Why Space Itself May Be Quantum in Nature - with Jim Baggott

Loop quantum gravity aims to unify the theories of general relativity and quantum mechanics, as explained by Jim Baggott.
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Quantum gravity is the holy grail for modern theoretical physicists - a single structure that brings together the two great theories of the 20th century: quantum mechanics and general relativity. One widely-known solution is string theory, which emerged from particle physics. In this talk, Jim Baggott will describe the other approach known as Loop Quantum Gravity. This theory starts from general relativity, borrows many ideas and techniques from quantum mechanics, and predicts that space itself is quantum in nature.
Watch the Q&A: • Q&A: Why Space Itself ...
Jim Baggott is an award-winning science writer. He trained as a scientist, completing a doctorate in chemical physics at the University of Oxford in the early 80s, before embarking on post-doctoral research studies at Oxford and at Stanford University in California.
This talk was filmed at the Ri on 12 February 2019.
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[@doronron7323]

I've watched RI lectures since I can't remember (I'm 64). Jim carefully talked his presentation through in such a way that I heard and could digest every word. Perhaps the sound effects weren't necessary, but otherwise he managed to avoid any other dramatic concessions. For an interested layman, I've never seen a better lecture on this or any other subject. Thank you.

[@krishnaprasadshivarpatna4726]

ಏಏ

[@krishnaprasadshivarpatna4726]

ಐಐಐಏ

[@crtxl]

The sfx were totally unnecessary and annoying. Therefore, I'll never know how it ended.

[@jangilbert8028]

I am in no way a mathematician! I just am fascinated by quantum theory etc. and this was outstanding!

[@bobaldo2339]

I agree. It is a great lecture!

[@allurbase]

If you already listened countless talks about general relativity you can skip to 38:00

[@thinkbolt]

You can skip it altogether, I'd say.

[@ferusgratia]

Thanks, I was just about to post the same thing.

[@dirkryan5962]

well that's just GREAT! i was at 36:24 when i read this. and considering i already had a decent understanding (for a non-physicist) of everything up to that point, it makes it sting just a little bit more. i almost aborted the mission because i wasn't hearing anything i hadn't already heard somewhere else. [note to self: read a few comments before committing to a 30+ minute presentation about quantum physics.]

[@fascistpedant758]

How dare he present information that you people at the center of the universe already know? Physicists should consult with you when preparing public lectures.

[@dirkryan5962]

@@fascistpedant758 i know, right?

[@RogerRosenquist]

He has a wonderful talent for making these extremely difficult concepts (somewhat) understandable while putting the listener at ease about not totally understanding it.😊

[@garyrafiq9561]

The closed captions (subtitles to you Brits) are great and error-free! Thank you, Royal Institution, for the captions, and the caption representation of the sound effects is helpful. Nothing wrong with those sound effects if they make the lecture interesting.

[@TheRoyalInstitution]

We try our best to make our videos as accessible as possible, thank you for your kinds words.

[@cmwh1te]

The sound effects should have at least been normalized in post production. Absolutely awful. Completely attention-breaking and pointless.

[@Daniel-sYouTube]

@@TheRoyalInstitution If we can wish for anything, a de-esser at the end would have helped to on all the sssss sounds ;) Other than that, great talk!

[@ShonMardani]

I am Shon Mardani, this is my Unifying Theory Of Everything, please let me know what you think, [GOD] Created NOTHING, a Void Point in Space. NOTHING Attracts [neighboring] Space, as the Only Law of The Nature, that gave the NOTHING its Property to be the GRAVITATIONAL PARTICLE (GP). Fast Moving Space into GP, Creates its own GP at the [vacated] Space and attracts the Surrounding Space. Propagation of the GPs in Cyclic Patterns Creates EVERYTHING. The Patterns' Frequencies in addition to to the Direction of GP Propagation are Observed as the Properties of the Matter, including Weight/Mass/Gravity, Magnetism, Electricity, Heat, Light and Color.

[@AndyinMokum]

As a layman, I found your lecture fascinating. The sound effects were quite alarming; especially for someone who's profoundly deaf in one ear. What sounds I can hear, are extremely distorted and Dalek like. Needless to say, I jumped quiet a few times 🤣. I'll have to watch the video a few more times. Some of the concepts you introduce, are really hard to get one's head around. They simply don't comport to our everyday perception of space and time. As I said, the lecture was fascinating, thank you for sparking my curiosity 😀.

[@anthonypacheco6482]

Someone somewhere is working hard to truly push this information into a new era of experience and conductivity! We can help by learning and pushing toward our own goals, no matter how small or large they may be! Cheers to the Roaring 20’s as they happen! So excited to see where all of this information heads 🧘🏽‍♂️🕰❤️

[@MrTommy4000]

I guess the first half rehash is unavoidable, but the second half was highly effective in guiding me towards a better understanding of the big picture. Cheers to all involved in producing this little gem !

[@martiendejong8857]

brb skipping to the second half lol

[@stevenesbitt3528]

I like the rehash, it may make total sense one of these days😂

[@Li.Siyuan]

Thank you for this; I've been looking for years for a clear explanation of LQG and now I've found it!

[@SirRelith]

This was such a fantastic explanation. I've watched several videos on loop quantum gravity and I believe this one to be the best so far.

[@jonathonjubb6626]

Yeah but it's all a bit contradictory, it's still - this should work cos every other explanation is even worse/less believable...

[@vhawk1951kl]

You understand that' quantum' is the Latin word for how much?

[@jasonking1284]

I'll believe it when they make their first warp drive....

[@steveray65]

"To see a World in a Grain of Sand And a Heaven in a Wild Flower, Hold Infinity in the palm of your hand And Eternity in an hour." William Blake

[@vicioussyd6870]

Life is like a box of chocolates Forret gump.

[@ANOLDMASTERJUKZ]

Great quote!.

[@shiitakestick]

It’s a state of mind..

[@SimonSozzi7258]

You know he took LSD right? 🍄🐛🦋🌈❤

[@vincebushell5543]

@@vicioussyd6870 too oo onn7n7n7n7n7n7n7n77n77n7n7n7n77n7n7n7n7n7nn7n7n7n7777n7n7n7n7n7n7

[@KilgoreTroutAsf]

For those familiar with history of physics, loop quantum gravity starts at 36:00

[@stefanluginger3682]

Thx

[@Youremywifenkwdave]

Hero

[@ShadowZZZ]

His melancholy is delighting.

[@eggsandwine]

"...have you heard the new album of Cosmic Metronome, Jim..." Brilliant! Thank you mr Baggott and RI for another excellent talk.

[@nickb9237]

Loved this presentation, I put it at 1.25x speed like the other comments suggested, not sure why everyone is griping about the SFx, I can’t watch regular science shows anymore, I only digest lectures from theoretical physicists. Loop quantum gravity is an alternative to string theory , I recommend Brian Greene’s “the elegant universe” for more on gravity and quantum mechanics. Thanks for posting this RI.

[@forbiddenera]

Because you're laying in bed deep in thought enjoying the lecture while you drift off and are suddenly assaulted and jolted by a distorted sound effect of someone screaming.

[@danievdw]

Really enjoyed the way Dr Baggot covered all this. Very interesting.

[@Quantumdemetrio]

I almost wanted to hit the desk for him at least once! hahaah, I love this talk. thanks so much for sharing.... love it.. again and again....

[@macbuff81]

RI is a great institution! Humanity at its finest :) I was never really good at physics in high school, but I feel I have gained great insight and understanding by watching these really intuitive lectures. Brian Cox had similar great lectures and TV series. SciShow and similar KZbin shows are similar great resources. I wish I had them when I was in high school in the 90s. Then again it's never too late to learn. I'm currently pursuing a master's in public health and I love it though it would be even better if I had scholarship :) It is nice to see how biology, physics, chemistry and psychology intersect. To understand the universe and use that understanding to make a difference. I would love to see a lecture live in person someday.

[@joshyoung1440]

Intersect... eh.. They're really all subsets of physics

[@Dr10Jeeps]

Excellent lecture! I loved every minute of it. A hearty thank you to Dr. Baggott and the RI. I can't recall ever meeting a RI lecture I didn't enjoy.

[@TheRoyalInstitution]

Oh you, flattery will get you everywhere.

[@RonJohn63]

59:34 Dividing by such a small number means that _S_ is *GINORMOUS.*

[@whatsonchannelB]

15:24 jeeez thanks for scaring my dog LOUD

[@lyonzeelyonzee7554]

LOVE ALL THIS STUFF ..GREAT VID....

[@davidwright8432]

If there's one thing that gets me mad, Jim, it's 'Don't worry about ...', since usually, that's exactly where I do want to go. Not understanding it, means it's what I need to find out about. That aside, an interesting and well-presented talk; thanks. And yes, Jim, I've bought several of your books, the latest included. Be bold, bloody and brave with the next one - and put the damn math in!! I'm sure I'm not the only one with that feeling. Hawking's editor who said every equation halves the sales, was an - ok, let's just say, was misguided.

[@pawelmiechowiecki7901]

Beautiful lecture, storytelling, narrations - very engaging.

[@glenbirbeck4098]

Great lecturer who knows about microphones and good audio.....brilliant !

[@maxkorn3910]

This is unimaginably awesome lecture where things I could not understand in the past were described so simply and clearly that I understood them all. Woah, just wow!

[@Khazam1992]

Can we do an experiement like projectile using Quantum Gravity/Space ? it seems fun to trace the path of a particle on the Quantized Space :)

[@carlkerstann8343]

Excellent explanation of where physics stands and how we got here.

[@JustJanitor]

Glad I found this youtube channel. This was great to listen to

[@HeliumXenonKrypton]

Really great video and explanation of LQG !! Thanks for this clear and helpful video.

[@kindlin]

Save yourself a half hour and skip ahead to 35:46, if you already have a cursory understanding of special relativity, general relativity and the inception of Quantum Mechanics.

[@thomascasey8171]

Fascinating and kept making me think fundamentally matter, energy are all comprised of momentum from the big bounce. (like the idea of a bounce instead of a bang) The particle/wave paradox seems like a clue. Nice to see that the singularity and it's associated mathematical infinity's are bogus (irreducible quanta). That always bugged a friend of mine and turns out he was right.

[@mariuszw5766]

Stunning. Absolutly stunning. The way you do the trick Sir is excellent. This is how you recognize a great mind!!! I'm a physicist myself as a graduate years ago and must say some ideas I' ve never even heard of.

[@Robyzed57]

WOW Dr. Baggott, thank you so much for the crystal clear explanation. I see Smolin changed his mind about Time, much to Professor Rovelli's annoyance, I suppose. Furthermore, as a layperson, I just hope one day to see string theorists and LQG supporters publicly confront each other, comparing ideas instead of filling square meters of blackboard with math....as I must confess I'm still unable to understand the substantial differences between the two approaches to the problem.

[@williamchurcher9645]

He said there were three approaches to get quantum mechanics and relativity to work together. One way s to just start again. Another is to assume quantum mechanics is correct and try and make gravity and relativity emerge from it: this is string theory. String theory says all particles are made up of strings vibrating in different ways. It also suggests a multiverse, where different universes like ours have different landscapes for the strings to vibrate on. For example, imagine in ours the strings wiggle on a flat table, in another the table is at an angle, causing the strings to wiggle differently, in another they wiggle on a wobbly surface. These different methods of vibration lead to different particles and different laws of physics. Another, third method, is to quantise gravity: this is loop quantum gravity. Einstein's relativity assumes space is infinitely divisible, but quantum mechanics doesn't like this: the Planck length is the smallest length possible. This LQG makes a new framework for what space and time is, (that graph network thing he talked about) and tries to make quantum mechanics appear out of it.

[@PazLeBon]

stop wasting minds on string theory altogetherId say, its little more than fantasy make believe

[@wmpmacm]

This is no surprise to me after all I have read about quantum mechanics and fields, etc.. Physicists have been working towards this for years. Nice to see it getting explained.

[@haroldkatcher1369]

The explanation that the gluon network holding the colored quarks together "snap" doesn't explain why quarks can't be separated. The explanation that the force needed to separate quarks would be enough to create a similar particle kind of does.

[@milantrcka121]

We need an audio peak compressor.

[@KuroSilence]

And a de-esser with some noise cleaning, these frequencies are pretty annoying...

[@shiitakestick]

you can get an equalizer app .

[@traviswessels5814]

What about dark matter and you have to take an account dark matter an expansion of space and time

[@traviswessels5814]

And also take an account that particles do have mass

[@traviswessels5814]

I should correct that some particls have mass

[@ChiefVS]

Definitely one of the best RI Talk I've heard!

[@VijayGupta-lw7qz]

Equivalence of gravity and acceleration: In picophysics first we explain formation of particles with its constituent space and Kenergy, and consequent interaction among themselves and space and quants.

[@markuskeller4281]

Thank you Jim!

[@coreyeaston6823]

This guy officially melted my brain.

[@johnnyaingel5753]

LOL so funny

[@MarcoAurelio-zu7sd]

If I were to take the diplomatic route, I'd say that as a speaker this guy is a great writer.

[@2ndAveScents]

Zzzz oop thing about public speaking....it absolutely is.

[@ITSME-nd4xy]

You’re too generous. He’s one of the best scientific dancers I’ve EVER seen! He dances around topics, with such fluidity.... Frankly, he’s an entertainer who’s memorized stories of science. Better to stay away, if you desire to learn. Nothing like that in his performances.

[@danielc.freteval5685]

Yeah because you can surely do better. Right?

[@amandayorke481]

Well, actually, there are points where I'd wish he'd go slower. I bet even regular physicists get slightly boggled when they consider the implications of ordinary on ordinary observations like the simultaneous lightning strikes NOT being as simple as they appear.

[@amandayorke481]

Don't know what happened to my grammar there!

[@dogone7262]

Space-time & energy-matter... Got it! Good talk!

[@nivlakhera9]

Incredible lecture , RI is fantastic

[@Daimo83]

I'm dying for some lectures that cover the subject from something higher than high school level. If he was my professor I would really fall out with him for telling me numerous times not to try to conceptualise important things.

[@hellstormangel]

god damn those audio fx effects

[@VijayGupta-lw7qz]

Time: In PicoPhysics we have two related chronological parameters. While time is distance between events; Samay is distance between Instants. All events constituting an instant are simultaneous. The kenergy konservation is studied with reference to instant.

[@LockSteady]

13:22 my favorite bit

[@BeyondWrittenWords]

55:24 'a single proton contains about 10^65 quantum of volume'. Quite a lot. And proton is small as hell.

[@gaslitworldf.melissab2897]

A WORK IN PROGRESS: I've listened to so many scientific lectures and enjoyed them thoroughly. I find that the majority readily admit that they don't have *absolute* answers, but they do know how to reason. The people who are obnoxious are the non-scientists that support science (as if it is infallible). Nothing is infallible, bc the human mind is imperfect. So, I take it as it is, an impressive work in progress (that often makes life better).

[@prisonerohope6970]

I like this comment

[@fromAZto09]

Regarding the lightning bolts experiment, it's easier to imagine you staying at first in the middle between them, and starting to run the same time they hit. Think about the fact that photons are speeding away from the left bolt, and you are trying to run away from them (towards the right bolt) at a fraction of their speed. This means you have time to cover some small distance before they hit you. On the contrary, the photons from the right run in the opposite direction, thus they will reach you a lot faster. I stopped for a while to think about this - because I'm not that bright (pun intended) - and I hope that this will help some other people as well.

[@michaelgilbert3684]

Lol not that bright pun

[@cheopys]

Baggott's "Interpretation of Quantum Theory" is the clearest book on the topic I have ever read.

[@michaelgilbert3684]

Greatest lecture ever heard. Brings everything into perspective!!:)

[@theseagull8842]

At one point you mentioned that the loops are not in space but are space. 2 questions - what is in between each loop, and what is in between from where you are looking and the loop you are observing?

[@MightyDrunken]

There is nothing between the loops. It is how they are connected which makes up the "fabric" of spacetime. Drawing everything in the same place looks confusing.

[@briandeschene8424]

The Seagull88 Maybe try this?: Light is quantized into photons and yet can usually be perceived and measured as an uninterrupted beam. But since proven to be existing in quanta, must be going on and off in between each photon quanta. If space itself is ever proven to be quantized, asking what is in between is nonsense since there would be no “place” to be “in between”. Best way I can perceive an answer. (shrugs)

[@georgeR3Roadster]

@@briandeschene8424 Haramein explains ( but I just mention this !! I do NOT say that I am a believer of his theories !! ) how the Planck quantas are related one to another ..... and how they should interact .... fascinating stuff everywhere !!!

[@hooked4215]

At the quantic level, time is undistinguishable from space since every particle moves at speed c, that is, the amount of Planck's length units displaced equals the amount of Planck's time units required.

[@trespire]

Lord of the Rings reference was spot on. Sadowfax was like a force of nature, riden by Gandalf one of the Ainur a race of beings from before the creaton of the World, also a fundamental power. J.R.R Tolkein was a master story teller.

[@World_Theory]

15:50 The thunder effect is pushing the words of the speaker into the noise floor. Needs subtitles badly. There were missed words. (Edit: On second thought, it might not have anything to do with the noise floor; it could just be a software thing. But the point still stands.) (Edit2: Clarification: There are subtitles available, but it looks like they're based on the audio from the video, and are therefore useless, as they include the sound effect as well.)

[@TheRoyalInstitution]

Unfortunately they were embedded into the presentation, we didn't add them in afterwards.

[@n3r0z3r0]

Extremely good explanation! Thank you so much! I would love to see more lectures with Jim.

[@TheRoyalInstitution]

Have you seen the one he gave about Mass? It's also very good - kzbin.info/www/bejne/fperm62lotaVkMU

[@ongbonga9025]

Fascinating. The immediate problem that springs to mind with this theory is the apparent expansion of the universe. If space is quantum in nature, what is expansion? It can't be the increasing in volume of one quantum of space, otherwise Planck's constant isn't so constant. So are new quanta of space being created? Another question I have is... if space is quantum in nature, does energy occupy space, or displace it?

[@jooky87]

Great talk, excellent speaker and summary of the current state. Basically we still need to convert spacetime from a continuous to a quantized geometric space.

[@prisonerohope6970]

I was just saying that... but not so succinctly

[@subliminalvibes]

Very interesting, thanks! ** LOUD AND UNNECESSARY SOUND EFFECTS WARNING TO HEADPHONE USERS **

[@craigwall9536]

A couple more of those and we're talking Class Action suit.

[@pete540Z]

Snowflakes complain about anything. Just ignore them.

[@julianBraga]

@@pete540Z lots of 'em here tonight! Pity.

[@jakelabete7412]

As usual, excellent treatment with all the depth you can get without going numerical (or symbolic). Good job Jim. By the way I could do without the sound effects - it cheapens the exposition and may startle some.

[@Josecannoli1209]

Jake LaBete the sounds effects are dumb and make it seem like they think we are dumb

[@jonnamechange6854]

But the sound effects help us to understand what a bolt of lightning is. Lightning is just the same as the Big Bounce. I've finally nailed this subject.

[@chrisnoecker5287]

wish there was more context and explanation -- for example, its clear as mud how Einstein concluded space-time was curved based off his thought experiments involving relative motion....

[@thepacificnguyen3107]

wonderful ... can't help but absorb every single word in this lecture. Trigger my imagination further into the realm of quantum physics.

[@impCaesarAvg]

Jim mentions the Queen Elizabeth Engineering Prize as being awarded 'today'. The award to Parkinson, Spilker, FrueHauf, and Schwartz was announced 12 February 2019. This lecture and that announcement were simultaneous -- unless you're moving very fast.

[@lucasthompson1650]

I wasn't moving very fast, the rest of you were moving very fast! 😋

[@Age_of_Apocalypse]

Jim Baggott, many Thanks: Great lecture!

[@zanyarebrahimi4563]

It was a very useful yet beautiful presentation of loop quantum gravity.

[@marcelifirlej1557]

To continue your research, I have impression particles maybe are made by gravity-loops, because mass is making deficit of space-time around it. However, does it consuming or restructures gravity knots when moving through the space as Earth around the Sun? How then the space curvature is constructed and have acceleration effect?

[@AwesometownUSA]

Jim “Don’t look for them, you won’t find them” Baggott

[@robertodanieles967]

This had me cracking up

[@augustosantiago6769]

To anyone complaining for little details as the sound effects... Why don't you just say Thank you Jim for your time and the lecture? Those people who ONLY criticize instead of being grateful are usually the ones that never contribute with anything in this world, but are always ready to find mistakes and wrong in what the other are doing. If you are so perfect, why don't you do a presentation as this one? It is very easy to criticize, but hard to recognize the effort and contribution of others... Very sad reality :-( Please, do not criticize now my English, it is my third language :-)

[@milantrcka121]

Well said!!!

[@ANOLDMASTERJUKZ]

Ditto that: baby!

[@OneTrueCat]

Because if nobody tells him the sound effects were grating and obnoxious, he won't know that people didn't like them. Constructive criticism isn't a bad thing. People can know there's a problem without being able to deliver the solution. You'd be absolutely livid if your car broke down, and you took it to a mechanic who fixed it, but now the turn signal activates a horn in the cabin every time it lights up, and the mechanic told you that if you don't like their fix, you should do it yourself.

[@augustosantiago6769]

People can criticize and being nice at the same time. At least thanks him for the presentation, then... Suggest him the improvement.

[@OneTrueCat]

Thanks isn't necessary for criticism to be warranted or polite. I couldn't enjoy it with the sound effects, and I don't feel that thanks are in order, but it's also not rude or incorrect to not thank someone for something you didn't need or enjoy.

[@jameshansen8220]

Define change. Define changing. Define language. Thinking and reason. Wisdom and information.

[@agimasoschandir]

Now or link to a dictionary?

[@neoness1268]

Wonderful lecturer 👌👌👌👌👌✨✨✨✨✨

[@michaelcoulter8477]

at 52:51 "Fluctuations in quantum space create the appearance of time." How can you possibly have fluctuations without having time to begin with?

[@michaelcoulter8477]

@@johnmpjkken3261 Seems nonsensical. Light moves through space. Light of a given frequency has so many oscillations per second. Therefore there is time in open space.

[@justynpryce]

I mean, you'd have to ask him to elaborate. Time to you means what it does to you, to him it may mean something entirely different. If quantum fluctuation are independent of time, as they would have to be otherwise space-time couldn't be a field, then I don't see why fluctuations couldn't be the cause of time. I'm not saying he's right, but I am saying he isn't instantly wrong because your understanding of time is different.

[@certaindeath7776]

quantum fluctuation may be a ripple of what was there before our universe caused time.

[@MathTutoringHelp]

I'm sure he really understands what he's talking about. You would probably have to ask him yourself.

[@PanicbyExample]

well you aren't supposed to have infinites either so lots of these ideas are based in mathematical proofs not so-called observably persistent illusions

[@Biga101011]

47:00 knot quantum gravity could possibly be the greatest misleading physics term if they went with that.

[@davehopefull]

lmao... it is pretty accurate.

[@Cyberplayer5]

Punny Physics.. XD

[@davehopefull]

@@Cyberplayer5 Nuance... smh. For the love of Jebus. Lmao

[@PanicbyExample]

great talk, good speaker

[@aprylvanryn5898]

I love how the falling man's scream was doppler shifted

[@sebastianelytron8450]

Best Ri lecture ever? Certainly a contender.

[@tncorgi92]

Could have done without the sound effects though.

[@MartinHodgkins]

Try Milo Wolff Wave Structure of Matter.

[@pepe6666]

i like that quote about scientists not agreeing on everything

[@VijayGupta-lw7qz]

Special theory of relativity: is an interpretation of Lorentz transformations. That established constancy of speed of light (independent of observer). In pico-physics, from unary law two constants evolve Planck constant and speed of light. The chronology of instants enable instant gap to be measured as Sammy. Space Energy kinematics enable spatial distance to be described in terms of time establish speed of light as another universal constant. Though not relevant here, the third constant established by unary law is fine structure constant. These three are fundamental constants and all other are derivatives, deductible values in pico-physics.

[@lfsheldon]

Clarity where I have never seen it before!

[@janhoogendijk8604]

Thanks to all life forms to bring us knowledge. Time is a stream of unchangeable changes that propagate in all dimensions.

[@FallenStarFeatures]

The reason the sound effects are disruptive is because they are crudely imposed upon the audio mix. By contrast, Baggott's voice is well-balanced acoustically, with a timbre and reverberance that sounds appropriate for this type of lecture hall. The sound effects are not only excessively loud, they lack the acoustic depth needed to make them sound like they're actually occuring in this particular room. Baggott's lecture was thoughtful and well-presented, it's too bad he didn't have assistance from an audio engineer to better integrate the sound effects.

[@irrefudiate]

I appreciate that physicists are trying to sort out space. Perhaps in the future they will be able to give it its own name and our common description of space as a gap between objects will carry on unimpeded and the phrase, "empty space", will be tacitly understood. As for time, I consider it a condition for existence, no matter how small or how short the duration. At any level, the nature of existence is time. If a bit of nature pops out of existence, then time can cease for that bit. But, I'm not a physicist nor mathematician and don't have to concern myself with those things.

[@mjtonyfire]

20:40 tough crowd

[@MendTheWorld]

Throughout, actually; and it makes me wonder why. i can’t blame it on the audience. it must be in the delivery. i’m very sympathetic, though, as whatever intangible speaking skills he lacks, i lack as well. Whenever i’m speaking and try to evoke a particular response, i nearly always fail. i think his success rate in this lecture was pretty close to 0.000 There HAVE been a few times, though, when things have magically worked as planned. It’s unpredictable, however.

[@TheGrassyKnole]

No need for the sound fx/ naive graphics. but otherwise excellent.

[@sanjuansteve]

The most intuitive way to explain how or why a particle like a photon (or electron, etc) might behave as an uncertain location particle while also like a polarizable axial or helical wave ''packet'', given that everything in the universe from electrons to solar systems are in orbit with something else pulling them into polarizable axial or helical apparent waves depending on the orientation of their orbits as they travel thru space is that they’re in orbit with an undetectable dark matter particle pulling them into polarizable axial or helical apparent waves as they travel. And given that we know we’re in a sea of undetectable dark matter but don’t know where it’s disbursed, we can imagine that they’re in orbit with an undetectable dark matter particle pulling them into polarizable axial or helical apparent waves as they travel where the speed of their orbit determines the wavelength and the diameter is the amplitude which would explain the double slit, uncertainty, etc. No?

[@rickharold69]

Excellent!

[@85zer0cool]

if space has gravity waves, space would be like a 3d ocean's top in my head. those waves should overlap even over themselves. would that create a "void" inside space? since the "void" would be "empty" it would not be able to break through the "fabric" of space, creating a outward expanding pressure inside the void. the void could still be shaped by gravitational effects causing it to be lumpy, smooth or both. could this be "dark energy" or "dark matter"?

[@williamchurcher9645]

(1) why should a wave overlap with itself? What does that mean? (2) the waves would not create a void, no. It's just rippling. Does the ocean surface create a void? You can only have a large ripple in one direction or a large ripple in another, or no ripple at all (constructive and destructive interference). (3) dark matter seems to be a particle, so you would have to have a stationary gravitational wave, which now that I think about it, is an interesting idea, but I'm quite sure it isn't a viable candidate for dark matter.

[@stanislavavramov8767]

some horrific sound effects there

[@jerryranelli6630]

@Sunamer Z më nnk p bb

[@chewyjello1]

I fell asleep to my KZbin channel doing it's auto-thing. That scream sound effect was not pleasant to wake up to.

[@topquark22]

"Three Roads to Quantum Gravity" by Lee Smolin, is the only book that ever caused me to miss my stop on the Toronto subway, because I was so absorbed in reading it.

[@GonzoTehGreat]

I'm reading it now. I agree it's an interesting book but Smolin isn't the best at explaining his work. He is definitely more interesting to listen to than this chap though!

[@loganpe427]

@@GonzoTehGreat This guy's only boring because you already know the subject matter beyond this level. To a general layman he's interesting enough, though personally I think even a layman could do without the sound effects, sheesh!

[@GonzoTehGreat]

@@loganpe427 Admittedly, the RI lectures are intended for the general public and pitch their content appropriately, but my issue was more with his lacklustre presentation style and explanation. Having said that, if you enjoyed the talk and feel you now have a better understanding of LQG then Baggott succeeded! However, I'd recommend watching a Sean Carroll RI talk for comparison, as I feel he does a much better job of explaining complicated physics. For example: kzbin.info/www/bejne/a5m5npiFeK-dhbc

[@johnjaksich3914]

Mr. Baggott is rather gifted at explaining QM -- I suggest picking up his book, The Meaning of Quantum Mechanics. Very good expositor of QM--

[@dahdahditditditditditditda7536]

Thanks for the great video. What impact might be impressed by LQG on the topic of quantum entanglement ?

[@pinkponyofprey1965]

7:16 "This is a theory for which there is no empirical evidence to support it" Almost like an ... hypothesis? :D

[@dustinsoodak8954]

I think his point was that we shouldn't let string theorists get away with claiming it is the ONLY hypothesis.

[@jellymop]

Actually hypotheses often have some non conclusive evidence or observations. This isn’t even an hypothesis. This is just speculation.

[@PazLeBon]

ive suggested that scientists of the last 50 years might as well be arguing for the existence of gods, theologists practically. To all intents and puposes 90% of science should be bout the here and now relevant to the lives we actually experience

[@dontwatchthat8933]

Granjacia we do experience gravity. And space.

[@PazLeBon]

@@dontwatchthat8933 lol I meant things like multiverses etc. Simply fruitless ;)

[@DanielSmith-nf2kt]

I'm not expert on this and don't know how the super computer works mathematically but didn't we quantize the space ourselves when we put the gluons and quarks on a lattice for lattice quantum chromodynamics which could give the appearance of quantified space?

[@mmaximk]

Thank you for giving me an intuitive model for loop quantum gravity - and for delivering that model in excellent banter!

[@JackLee7223]

It certainly explains Xeno's paradox perfectly.

[@MechanoRealist]

No it doesn't, because Zeno's paradox of Achilles and the tortoise is essentially a joke. It's like Schrödinger's cat, a thought experiment to highlight that something so obviously ridiculous shouldn't be taken seriously. Any yet some people still do... 😂

[@PazLeBon]

@@MechanoRealist that seems flawed to me anyway, that entanglement. because they only confirm the rule itself after observation. i.e observe A, therefore the other is B. Observe it, confirms it's B.But until we observe it it could be an unobserved A. How am I wrong?

[@pismar2]

I found this video looking for an answer to this paradox.. If we assume space and time are continuous then they both consist of infinite monads of nothingness.. infinite points of no dimension (space) and infinite moments of no duration (time)

[@gravijta936]

Relativity from the perspective of the British Empire: "I don't have a goofy accent, you have a goofy accent!"

[@jakelabete7412]

Lord Rutherford when told that British physicists were ambivalent about relativity theory is reported to have quipped that 'they have too much common sense to buy into it'. Misguided, but funny.

[@PazLeBon]

@@jakelabete7412 they continued that ambivalence into COVID days

[@joeltarnabene5026]

A sidenote. It seems to me that particle physics is the real interpretation of the universe, while relativity is an approximation on the macro scale. Just like Newton's theory of gravity was a more imprecise approximation before that. I think we need to abandon relativity and try to extrapolate new macro theories from quantum mechanics.

[@esdrasvelazquez5416]

The question about the twin bolts is answered by understanding that relative to speed is distance, as you travel from left to right you shorten the distance from one volt and increased the distance from the other, if you do the math and sum the total speed and distance of the man standing still and the one moving they both get the light in the same relative time. The reason why man has not found the secrets of space and time is its ego, we seem to belive everything is made for us and when we find something that does not behave acordingly to our ego, it is discarted.

[@agimasoschandir]

[... they both get the light in the same relative time.] The person moving did not

[@inyan4361]

why the need for the sfx"soundeffects"? its so random

[@ClariceAust]

It's probably an old habit he still uses of waking up sleeping first year physics students(?) (I agree, not necessary and annoying.) But who's going to knock this guy; great lecture.

[@ITSME-nd4xy]

A poor lecture. His sfx are there for entertainment - while he dances fluidly around topics he barely touches. One of The BEST scientific dancers I’ve ever seen! Turn off the audio, and you’ll learn even more!