"just quickly, let's review all of quantum mechanics" LOL

@RobertKaucher

4 жыл бұрын

Indeed!

@RumoredAtmos

4 жыл бұрын

I laughed at that too

@meleardil

4 жыл бұрын

Well... he did...

@Seeyeay

4 жыл бұрын

It was actually really well done, seemed to piece together other concepts that I had learnt separately in previous videos.

@emanuelebonura783

4 жыл бұрын

No doubt my man here delivered a solid and concise explanation (like always, I freaking love this channel), but I lolled so hard nevertheless

"Let's review all of quantum mechanics." "Actually, quantum mechanics forbids this."

@liggerstuxin1

4 жыл бұрын

listenatwork99 👏

@moosemaimer

4 жыл бұрын

you can either know all the equations, or which ones are correct, but not both

@LuisAldamiz

4 жыл бұрын

QM is uncertain about this, mind you.

@paulmichaelfreedman8334

4 жыл бұрын

And even then your answer is not 100% correct ;)

@JF-go7gc

4 жыл бұрын

@@moosemaimer they are all correct....just depends on which reality you perceive and work them out from

I feel like a dog watching humans talk.

@darkmath100

4 жыл бұрын

LOL

@sefyboy7183

4 жыл бұрын

@C R Stop talking, you social brick.

@Mandeepd13

4 жыл бұрын

acuurate af!

@kinngrimm

3 жыл бұрын

I wonder if dogs can do as we do when we anthropomorphize them.

@glarynth

3 жыл бұрын

A dog named Spacetime.

9:07 - For everyone wanting to learn more about the topic - "Quantum Gravity" I suggest reading these two books - "Three Roads to Quantum Gravity" by Lee Smolin and "Reality is not what it seems" by Carlo Rovelli. They are masterpieces especially the one written by Carlo Rovelli really gives you a great insight into this topic.

@ramsesabreu1870

4 жыл бұрын

Yeah, Carlo Rovelli makes a clear, concise mention of Quantum Gravity in "The Order of Time".

@DanaNourie

4 жыл бұрын

Ajinkya Naik a great book!

@shaunhumphreys6714

3 жыл бұрын

@@ramsesabreu1870 yes i concur-carlo rovelli also teaches the philosophy of science so you get quotes from classical greek and roman philosophers in his books, and declaring stuff like love more than the sum of its quantum parts. i dont like lee smolin as he is a time denier.

@shaunhumphreys6714

3 жыл бұрын

carlo rovelli should be the first one to consult-he marries theoretical physics and philosophy in a wonderfully intuitive way. he is an intuitive physicist, however loop quantum gravity is a weak theory, very contrived. electromagnetic, strong and weak nuclear force were quantised fast and easily and with incredibly accuracy. gravity cannot be quantised.it refuses to be. it has resisted every attempt. noone is anywhere near. because gravity is not a force, it is rather the effect of mass in changing the geometry of the spacetime itself. it's a geodesic. which is spacetime itself, so it doesn't involve any particles mediating a force like gluons, w and z bosons and photons. and for relativistic lorentz transformations to hold, space and time must be continuous, not discrete. otherwise they relativty is violated. the universe may be quantum, without everything being discrete. i had dismissed string theory for a long time, but it is far more likely than loop quantum gravity, and is a complete framework, that answers the suggestions of either higher dimensions in physics, or holographic principle suggested by blackholes.

@janouglaeser8049

3 жыл бұрын

@@kabirmunjal9149 I'm sorry, I'll stick being team Thiemann 😝

"Loop quantum gravity tries to quantize general relativity, with no strings attached." I see what you did there!

@peachybeck

3 жыл бұрын

should be called “no strings attached theory” lmao

@_sayan_roy_

3 жыл бұрын

That was pretty obvious though

@seancanning6743

3 жыл бұрын

Well if its in the box it ain't brand new. Try on hauls. Haha

@raysubject

3 жыл бұрын

most epic comment on any PBS video ever... almost died by laughing... yeah, i feel that way all the time :-))))

@chicxulub2947

3 жыл бұрын

blasphemy

"So quickly, let's review all of quantum mechanics" Sounds like the last math class before an exam...

@frankdimeglio8216

2 жыл бұрын

Invisible AND VISIBLE SPACE in fundamental equilibrium and BALANCE IS E=MC2 AS F=ma, AS ELECTROMAGNETISM/energy is gravity. Indeed, the ultimate mathematical unification (AND UNDERSTANDING) of physics/physical experience combines, BALANCES, AND INCLUDES opposites. (Very importantly, outer "space" involves full inertia; AND it is fully invisible AND black.) WHY AND HOW ELECTROMAGNETISM/energy is gravity, AS E=MC2 IS NECESSARILY F=MA: TIME DILATION ULTIMATELY proves ON BALANCE that E=mC2 IS F=ma, AS ELECTROMAGNETISM/energy is gravity. INDEED, TIME is NECESSARILY possible/potential AND actual IN BALANCE; AS E=mc2 is F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity IS ELECTROMAGNETISM/energy. E=mc2 is F=ma. This NECESSARILY represents, INVOLVES, AND DESCRIBES what is possible/potential AND actual IN BALANCE, AS ELECTROMAGNETISM/energy is gravity. The stars AND PLANETS are POINTS in the night sky, AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. (Energy has/involves GRAVITY, AND ENERGY has/involves inertia/INERTIAL RESISTANCE.) Very importantly, outer "space" involves full inertia; AND it is fully invisible AND black. BALANCE AND completeness go hand in hand. It ALL CLEARLY makes perfect sense. Great !!! Gravitational force/ENERGY IS proportional to (or BALANCED with/as) inertia/INERTIAL RESISTANCE, AS E=mc2 is F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE, AS E=mc2 is F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. "Mass"/ENERGY IS GRAVITY. ELECTROMAGNETISM/energy is gravity. The Earth AND the Sun are CLEARLY E=MC2 and F=ma IN BALANCE, AS ELECTROMAGNETISM/energy is gravity. The stars AND PLANETS are POINTS in the night sky. GREAT !! By Frank DiMeglio

@ikilledaman

2 жыл бұрын

@@frankdimeglio8216 That is all nonsense

@NecDraws

2 жыл бұрын

@@frankdimeglio8216 ahm... nope..

@joshyoung1440

Жыл бұрын

@@NecDraws lol do you happen to remember what he said?

"Bröther may I have some quantum lööps?" -Schrödinger's cat, shortly before death (maybe)

@liianhaalea1088

4 жыл бұрын

Underrated comment. Fabulous.

@nicolasribeiro7914

3 жыл бұрын

this is absolute gold

@whythelongface64

3 жыл бұрын

It's still funny. I'm from 2021.

@jorikito

3 жыл бұрын

Can confirm, it's still funny in 2021

@matthewobrien4745

2 жыл бұрын

Can also confirm for 2021: Ts bussin in humor respectfully

"With no *strings* attached.". Hands down one of the best puns ever.

I'm going to need this explained again... much slower... with finger puppets.

@martiddy

4 жыл бұрын

I'd recommend you to check his other previous videos before watching this one, it will help you to understand some terms and physics processes.

@PuzzleQodec

4 жыл бұрын

Cute little finger spinors. Sounds good!

@kareldegreef3945

4 жыл бұрын

well he's full of it => there are no sub atomic particles => that's just a model to understand !!! he's brainwashed as well => there only fields !!! just saying => youre not missing out of much here ;-)

@closair

4 жыл бұрын

Matthew White so you need Alton Brown’s explaination

@martiddy

4 жыл бұрын

@@kareldegreef3945 so please tell me how chemistry works then, or how the computer/smartphone that you're using to access to internet works without atoms and electrons.

*Best. Host. Ever.*

@MirorR3fl3ction

4 жыл бұрын

Matt is easily one of my favourite hosts on KZread, but I mean Gabe was pretty cool too, plus he was the one who managed to explain the basics of General Relativity to me back in those early videos. I think it'd be cool if Gabe came back to co-host once with Matt

@enterprisesoftwarearchitect

4 жыл бұрын

Gabe!!! Matt is fun, of course. And working hard along with the writers.

@kendomyers

4 жыл бұрын

Said the tapeworm

@fensoxx

4 жыл бұрын

Gabe explained black holes to me better than I’ve ever heard it explained. They both shine in their own way. We are damn lucky to have them.

@neilwilliams929

4 жыл бұрын

I won't say best host ever .......That's a very bold comment "! But matt is very much a great presenter .👍

I find it fascinating how deep we're going. It's going to get to a point where it's meaningless to talk about spacetime, mass, charge and other familiar concepts to us, and it's going to be purely abstract exchange and evolution of data. It's like Sims finding out they're made out of bytes.

@Alpha_beef

4 ай бұрын

Definitely. Also increasingly highlighting some of the push and pull between math and physics

"A seriously loopy space-time, with no strings attached."

@Cosmalano

4 жыл бұрын

Bertrand de Born that moment when you don’t like pop science using silly words so therefore all of physics is wrong.

@Cosmalano

4 жыл бұрын

Bertrand de Born pop science gets people, usually kids, into the subject that become professionals later. And if you seriously think there’s not been any progress in over 70 years in that field you’re either trolling or uneducated. I’m in that field and I assure you there is plenty being done, try reading up on it.

@Cosmalano

4 жыл бұрын

Bertrand de Born do you know quantum theory or general relativity or are you basing this solely off the claims of others that say they do?

@Cosmalano

4 жыл бұрын

Bertrand de Born okay so you aren’t a physicist. That’s all I needed to know. Tesla wasn’t a physicist and there is no such person as “Feynstein”. Keep studying.

@Cosmalano

4 жыл бұрын

Bertrand de Born Einstein has not formal education? That’s patently untrue. Get it? It’s a pun because he worked in a patent office while he was completing his formal education.

"How to talk to your kids about loop quantum gravity"

@kendomyers

4 жыл бұрын

Its time we talk...

@ffggddss

4 жыл бұрын

"If a stranger walks up to you and offers you a loop of quantum gravity candy, ..." Fred

@naotamf1588

4 жыл бұрын

I just watched the recent Vsauce2 video. From about 8min towards the end Kevin explaines non-transitive loopholes (gamelogic), and that is how It became quite clear to me. Maybe we are in a simulation after all and LQGs are some sort of q-bits in an endless cycle of non-transitive loops batteling out equilibrium?

@paulmichaelfreedman8334

4 жыл бұрын

say that and their mouths begin to water...Fruit loops is what came to my mind first too...

@gwddmt1

4 жыл бұрын

*When a quantum Mommy gravity falls in love with a Daddy wave function and they make a special loop connection and...*

“bröther, can I has quantum lööps

@melparadise7378

4 жыл бұрын

🥣

@TheNamelessOne888

4 жыл бұрын

But X Terminal, you already have quantum loops, too many to caunt.

@Steevo69

4 жыл бұрын

How about a Moose with a toothbrush?

@mufaromandaza

3 жыл бұрын

🤣🤣🤣🤣🤣🤣🤣🤣 very funny

@ujjalshill6442

2 жыл бұрын

But we have quantum loops at home

Masterpiece of physics presentation. For any budding physics geeks 16 year old, this is a treasure.

It must be weird being that guys kid, "son, it's time we had a talk about loop quantum gravity"

Me: oh look a new PBS Space time video, and the title sounds so interesting! 2 minutes into the video: I have no idea what is being discussed here and I think my brain is oozing out of my ear

@icollectstories5702

4 жыл бұрын

Re-watch the older vids; this one's pretty far down the ol' rabbit hole. This series is trying to guide you step-by-step, so you might have missed one.

@ChasingTheDelta50

4 жыл бұрын

lol 18 kid who love quantum mechanics: grabs popcorn and is pumped for the new videos on favorite science channel and understands all of it ahhahahaa

@ugoeze7360

4 жыл бұрын

That’s not brain that’s oozing... 😰

@mthokozisilanga4497

4 жыл бұрын

MJ Music 🤣🤣🤣

@chrissonofpear1384

4 жыл бұрын

All about the smallest bits of space being small 'loops' at the Planck scale, where space and time is potentially quantised. And, per some models, spacetime may be itself an emergent phenomena from, say, entanglement itself...

If space is actually a 'pixel grid' of loops, and space is expanding, does this mean that the loops themselves are expanding? Or are the loops 1 dimensional and therefore cannot expand. I would assume if they have constant size like the planke length, there are more loops being created as expansion occurs. I know common sense doesnt work at this scale so any help would be appreciated! Ty!

@FredDufresne

4 жыл бұрын

Updoot for answer

@FairyRat

4 жыл бұрын

That's a good bloody question.

@godm0de

4 жыл бұрын

I lost you at 'if space'

@SeraphimKnight

4 жыл бұрын

I don't think it works that way. Think of it like zooming an image on a screen; you don't get more pixels on the screen, just the image is stretched across more pixels. At least, that's how I understand this.

@CharlieLOL

4 жыл бұрын

One dimension we are familiar with. Not necessarily one total. Expansion is a relative term. #oneloopuniverse

"Which is a concept too abstract even for this episode." Hahahaha!

" I like my gravity loopy, not stringy"

Me: Oh boy, I am tired. Today was really exhausting. PBS Space Time: Loop Quantum Gravity Explained Me: Yes I definitely have the energy for this. EDIT: Okay, I actually did get a bit of a hold on this concept. I definitely need to start watching more of your videos to truly be caught up, but I cannot express how grateful I am for you guys to be making all these ideas approachable for people like me. It’s a gift.

Whoever does your graphics, give them a high-five for me. They are well thought out, and awesome.

@Tabu11211

4 жыл бұрын

And a second hifive for me. Person needs hifives.

@LuisFlores-gz9of

4 жыл бұрын

17:22 there you go

@sakykBzz

4 жыл бұрын

really? i thought they hired a new one for this episode. they were horrible

@derekokeeffe9919

4 жыл бұрын

another high5 from me

I would say this is probably one of the best videos, educational monologues, that I have ever had the pleasure of listening to.

im very thankful for your videos. I have been following since the start of my qft journey. You guys give the big picture of what all this maths is for

I understand literally every other video you've done, but this space of loops sends me for a loop in space.

@yawgmoth6568

4 жыл бұрын

No you don't lol.

@ChadPANDA...

4 жыл бұрын

@don't matter r/woosh

@kdhavle

4 жыл бұрын

He's Sid, out Fire God!

In today's episode of "holy hell that title's already making my brain hurt" Followed about twenty minutes by "brain hurts a little less but this makes more sense I think?" Followed an hour later by "I still don't get it :("

@noelegarland

4 жыл бұрын

I've just gotten used to the fact that I'm dumb. I just come here hoping some smart might stick to me if I rub up against it enough.

@timeisyonger695

4 жыл бұрын

I understand it more then string theory but it is hard (:

@upgrade1583

4 жыл бұрын

In summary he said.... Life is heaven. Death is hell.

@Canadian_Ry

4 жыл бұрын

@@noelegarland I'm on that boat. Cheers, my dude.

@KenMathis1

4 жыл бұрын

I'm here for the journey because I'll never reach the destination.

This is beautifully explained - I'm a physics student, finishing up my fourth year at uni, and even with having studied Quantum Field Theory and General Relativity, I find string theory and LQG almost unapproachable to understand. Most explanations I've found tend to get buried in the maths without every really explaining the idea of the theory itself . This, however, succinctly explained both the motivation and idea behind the theory in a simple manner. Thank you very much!

One of the most comprehensive videos I’ve seen on this subject yet.

"So just quickly, let's just review all of quantum mechanics." Good one, Matt.

@velnz5475

4 жыл бұрын

this statement was made at the phanerozoic eon, cenozoic era, quaternary period, holocene epoch, 12019 HE on October 15th; all of quantum mechanics would take longer then the entire phanerozoic eon itself lol. Matt just breezed through in a 17.5 min video...

I see you've broken down holonomy and spinor bundles into somewhat digestible somewhat normal words, and I optimistically challenge you to do the same for topos theory and quantum logic.

@Tabu11211

4 жыл бұрын

No idea what that is but I am excited for it.

@SuviTuuliAllan

4 жыл бұрын

everyone: give us maths spacetime: we don't do that here

@bobbysanchez6308

4 жыл бұрын

Indeed

@martiddy

4 жыл бұрын

@@SuviTuuliAllan If you want to know a more mathematical explanation about theoretical physics, then I highly recommend you the channel Sixty Symbols.

@jovetj

4 жыл бұрын

There are too many types of sleep that we don't know about but experience.

I'm so amazed i understand this, thanks for the awesome explanations every time

"So quickly let's just review all of Quantum Mechanics," best throw away line so far.

This is one of the best PBS Space Time episodes I have seen yet. Good shot!

I think I stroked out after he said "So just quickly let's review all of quantum mechanics"

@nicolasribeiro7914

3 жыл бұрын

not only you

So you come home, and there he is, Matt O'Dowd, sitting in your kitchen: "It's time we talked about Loop Quantum Gravity."

@michaeljubara9397

2 жыл бұрын

Yep, ain’t life wonderful!

If anyone is interested, a really great book on this is "Reality Is Not What It Seems: the journey to quantum gravity" by Carlo Rovelli. He makes the topic super approachable while also going into enough detail that you feel like you actually learned something. I would totally recommend it! (But maybe skip the first couple of chapters because its just kinda superfluous history 😅)

Bröther, may I have some *Lööp* gravity?

@mathematicalninja2756

4 жыл бұрын

Lol

@olas2012

4 жыл бұрын

You've won the nerd internet today. I applaud you

@KungKras

4 жыл бұрын

Don't forget to mentally pronounce the "öö" in the Swedish or German way. Otherwise you're missing out.

@VigiliaMortisYT

4 жыл бұрын

Came here just for this comment xD

@koenvandamme6901

4 жыл бұрын

*smacks universe* It fits mäny lööps.

I've been watching (and rewatching) Dr Leonard Susskind's lectures on General Relativity. So I think I actually understood most of what you presented here.

'Not true, damn..." Very nice. Took me a second. It was so good that if it hadn't have been for the preceding puns, I would have definitely missed it.

Really nice explanation of LQG. Great fun! Thanks to your supporters.

I'll never open a can of Spaghetti-Os again without thinking of loop quantum gravity.

@velnz5475

4 жыл бұрын

wait people eat those? I mean... im surprised its still around

woo ive been waiting for this episode for so long! as a fan request, could you do one on quantum darwinism or conformal cyclic cosmology (ik the latter you gave a quick reference in a video a bit ago), i feel like especially with the quality of animation you guys have both of those topics would be super lovely to watch a video on

Lovely video , THANK YOU. Thank you for not watering this down and great job with reduction.

Awesome episode! I'm going to have to watch this a couple more times.

Awesome, I've been waiting for this!!

How do we think about cosmic inflation and expansion in the context of LQG? Is it new loops being added to the fabric of space? Or just a reconfiguring of the connections between them? Or both? What does a black hole look like in LQG?

@kindlin

4 жыл бұрын

I really did love this episode, but I want to see a whole nother episode with all of these questions, now, too!

@jackburton8352

4 жыл бұрын

i am working on theory that i call quantum smearing which comes close to unifying relativity and the quantum world. look out for it early next year looking to publish around March

@chrissonofpear1384

4 жыл бұрын

Mmm, I would be interested in that, Jack. Also, any thoughts on Doubly Special Relativity? As formulated by Amelino-Camelia and others?

I only understand about 20% of the content in these videos but I can't stop watching them.

16:10 - Man! I want to hear more about naked singularities! Looking forward to the episode!

Interesting as always. In a perfect vacuum, modeling the most particle-sparse regions of the universe, is there an expansive effect?

You know, I love that this show exists and I have been a patreon supporter for quite a while... but some of these episodes... melt my brain. I am just a poor social scientist! I won't stop watching... but man this channel is intense sometimes.

This is actually really intuitive to follow

this was such an amazing watch! This actually jogged my mind back to a notion i was contemplating trying to understand gauge theory, for some reason in my head it related to governing of limiting degrees of freedom for subatomic interactions but governance with the shape of extremely small extra dimensional space, when this stuff connects in this conceptual way.... it gives me goose bumps.

Very interesting. I wonder why exactly they started with an abstract space of metrics on 3D slices instead of an abstract space of 4D metrics in the first place? I'd love to learn more about this problem of time.

I think this theory has more potential than string theory because it is much less complicated and it might predict something verifiable

@vyhozshu

8 ай бұрын

we should gauge the theories with priority being "that which requires the invention the fewest new invisible dimensions to work" 😁

@Feroxing12

7 ай бұрын

dont worry string theorists will add 17 extra dimensions for their formulas to work.

"So let's just quickly review all of quantum mechanics". Delivered completely straight and dry. I love it.

Great episode as always

I would like to take a moment to appreciate how unfathomably smart these people are.

@darioinfini

4 жыл бұрын

I have a theory I want to propose -- most people seem incredibly dumb to me. And then there are people like Matt who are outrageously smart. It seems to me that the same way there is a massive wealth gap with a handful of people owning half the world's wealth, there are a handful of people who are in possession of half the world's intelligence. Call it Intelligence Inequality.

@brucecampbellschin8632

4 жыл бұрын

If I was as smart as half of these guys I'd be showing off to all the ladies.

@darioinfini

4 жыл бұрын

@@brucecampbellschin8632 LOL you literally made me laugh. If you were just a little smarter you could have worded that right -- if you were half as smart as these guys... Or maybe you were just proving your point, in which case, on point!

@brucecampbellschin8632

4 жыл бұрын

@@darioinfini Both I'm at work and it's actually so boring my brain doesn't work properly AND I was falling asleep while watching the video.

@darioinfini

4 жыл бұрын

@@brucecampbellschin8632 I was awake and I didn't get it either. Was just kidding bro. That guy makes a lot of us feel like we have no clue what's going on. This video I was basically lost from the start. Usually he loses me about 1/2 to 2/3 of the way in.

Universe: Okay little humans, what is this picture? Humanity: Uhm...it's a ball! Universe: Are you sure? Humanity: Uhm...no, it's a string! Universe: Are you sure? Humanity: I dunno. Oooh, wait, it's a loopy thingy! Universe: Sure about that?...

@TlalocTemporal

3 жыл бұрын

Cloud? Toroid? Quaternion? Mandelbulb? Little maintenance men with flashlights?

@berk6240

2 жыл бұрын

kzread.info/dash/bejne/hYyEz7SMeNeeZsY.html interview with Carlo rovelli, one of the founders of loop theory

Been waiting for this video, thanks.

I have absolutely no idea on mostly what you are talking about but I keep coming back because it's interesting and I want to learn

I'm a simple man. I see a new PBS Space-time video and I press like.

So your explaining something I have never heard of, this should be interesting.

This makes so much sense on a macro level. GR tells us the background or stage (space) is dynamic, therefor QM must take that into account. Einstein tries this in the 1950’s but it was a mess. In 1965 the Wheeler-DeWitt equation attempts this, but is unsolvable... until you utilize the information in the connections of space. Those ideas and that path seems seem like a very logical way to reconcile GR and QM. This is currently my level of understanding and I get lost in the math beyond that, but it seems like the idea for the structure and form of loops comes from the connections utilized in the math. Going from mathematics and abstract understanding to a solid picture is always the hard part. Moving from analogy towards reality. Love this stuff. Graphics guy or team is amazing. Best in the biz.

Wow... It's going to take a few viewings to understand this, even though you did it an amazingly non-mathematical way. Something tells me this is the most accessible description of Loop Quantum Gravity anywhere.

Since loop quantum gravity defines the smallest possible time as well as the smallest possible measure of area and volume, could it be possible the appearance of wave functions/particles duality arises from the topographical uncertainty of the quantized "space" said particle information has to pass through?

@keegsmarshall6610

Жыл бұрын

I certainly wonder about the whole particle/field distinction and whether it needs reexamination.

Thank you so much for reminding me how little I know, friend. I'm gonna go eat some crayons now.

@ramonpizarro

4 жыл бұрын

Save me the blue ones, they're my favorite

@chinkeehaw9527

4 жыл бұрын

A Troll I think you're gonna let someone else do the job considering your name

I waited for a video on loop quantum gravity... And here it is... ♥️♥️♥️😎 Thank you for making Awsome videos♥️😍

you give me the shivers man.

@3:30 "So, just quickly, let's review all of quantum mechanics..." 😂😂😂😂

13:01 Thank you for mentioning that. That was such an amazing observation. As attractive as loops are to me when compared to strings, they don't seem to agree with the data. As Sagan put it, our preferences don't count.

@LuisAldamiz

4 жыл бұрын

That's probably only because they haven't hacked time hard enough.

@kennedystapleton2279

4 жыл бұрын

He did imply that it may have been unmeasurable (to current technology). Stating this, I would love to know if the measurement was made with a significance to confidently count out loop quantum gravity.

@LuisAldamiz

4 жыл бұрын

@@kennedystapleton2279 - The problem is that there's only been one such measurement, so the confidence is necessarily small. AFAIK the measurement was performed on light traveling from a neutron star collision a very long distance away, collision detected only via gravitational waves. The measurement also suggested that gravity travels a tiny bit faster than light (or that light is delayed a tiny bit more than gravity at such extremely long distances, a more reasonable explanation in principle). More research is needed...

Thanks for the video .. very illustrative ..

Very good explanation. thank you!

09:20 I would have called this theory "Chainmail Spacetime Gravity": CSG [the letters themselves even look like what it is described on each aditional dimension].

Can you make a separate video on the experimental predictions of both string theory and loop quantum gravity ?

I rarely understand what he's talking about but enjoy hearing him say it.

I remember having commented on LQG in another episode, esp. on its prediction of slowed-down gamma photons - an effect that clearly violates Lorentz invariance. Indeed, LQG, as designed by Lee and Smolin, treats time as an extra variable different from space. I would be really glad to see LQG translated to a manifest Lorentz invariant form...

I feel like every time there's some weird shit going on in physics and cosmology, Carlo Rovelli is always involved.

@LuisAldamiz

4 жыл бұрын

That's a plus, Smolin is also cool.

@martiddy

4 жыл бұрын

That's when you know you're doing something good as a theoretical physicist.

@jovetj

4 жыл бұрын

He's got his noose in everything.

@chrissonofpear1384

4 жыл бұрын

Wait til you hear about Doubly Special Relativity...

@sebastianbermudez4081

3 жыл бұрын

He's an incredible human being and very charismatic, I really like to hear him speak about physics, reality and life.

That's a good explanation, thanks, just what I wanted to know.

IMHO, your best episode ever.

To those who are interested in loop quantum gravity and perhaps are quite confused about it, I would highly suggest reading the book "Reality Is Not What It Seems" by Carlo Rovelli. It is so beautifully written, and it gives an entirely different perspective on the nature of reality where time does not exist.

@enterprisesoftwarearchitect

4 жыл бұрын

Raul Lasagna skydivephil’s KZread channel has a very approachable interview with Ashetekar (spelling?) himself.

@chrissonofpear1384

4 жыл бұрын

Thanks. Mainly I've been looking at Lee Smolin's books on this sort of thing...

That fractal loop spiral you showed...where can I look at a good 10 minute video of that. That was so awesome. It went 3D.

Almost like a there was causality universe collided with the singularity and both are intertwined. Definitely awesome channel.

Read all Carlo Rovelli books, even bought his Covariant Loop Quantum Gravity !! Your video is such a good explanation of Ashtekar, Smolin and Rovelli's work... thank you very much for that ! A french fan of the only real quantom gravity theory that could work indeed xDD

@kalonji64

4 жыл бұрын

And about the time problem in the loop quantum theory, in his books Rovelli well explains that in a when we approach quantum sizes, time seems to be no more needed in the equation so it works even in a 3d space ;) edit : not sure I'm beeing understood, if not, please read Revelli's books xD

The loops in loop quantum gravity don’t sound that much different from looped strings. I guess the math probably makes it more distinct by not needing multiple dimensions but can you expand on the differences of these fundamental pieces, please?

@Aleonore22

4 жыл бұрын

Hi Matt! (I'm sure he's going to answer your question)

@joshuahillerup4290

4 жыл бұрын

They're made of something different

@loganfisher3138

4 жыл бұрын

One is made of spacetime, one is made of string. That's not a trivial difference.

@scottmiller4295

4 жыл бұрын

yea or maybe the curled up dimensions or something either way both camps are currently working together to try and bridge the gap where they had been dead set rivals for THE theory rather elitist eh?

@CasualGraph

4 жыл бұрын

In string theory the loops are particles, in LQG the loops are space, I think.

One of the biggest things I've always had trouble wrapping my head around about LQG, is why spin is the quantum operator that is used to mathematically represent the fabric of space. In what way does adding quanta of spin - as opposed to any other quantum operator - to the connections used to describe space, make the space of metrics appear just like a space of quantum fields, thus enabling gravity to be quantized, in a way that it could not be with connections built from regular ol' vectors?

@AliceYobby

2 жыл бұрын

This is a question that can only truly be answered with a PhD

@Nukestarmaster

2 жыл бұрын

LQG uses spinors for the same reason that String Theory needs 6 (7 for M theory) extra spatial dimensions. That's what makes the math work to produce a model that resembles reality.

@stevewhitt9109

Жыл бұрын

The spin in LQG is NOT the same thing in QM

@Manguadesignz

Жыл бұрын

Bruddah English pleassssse

@matthewparker9276

Жыл бұрын

Something that could be relevant is that point like singularities in GR become loops when they gain angular momentum. If there is a minimum angular momentum (i.e. quantised angular momentum) then any point masses become loops. Idk if that's actually relevant, but it feels like it should be to me, at least on some level.

I would be quite interested to know how the properties of the gravitational field change depending on the temperature of the body. When energy is added to the motion gravity should increase. The same thing should work with energy supplied in other forms.

I learned about LQG after I had an insight into Turing machines, the stopping problem, and the discreet nature of the Universe. A puddle of mud is Turing complete depending on how its inputs and outputs are considered. This Turing completion happens in nature at every scale both quantum and GR scales. This sort of Turing-completeness is almost axiomatic. Its a property of the universe itself and everything from computers, human brains, to bottles of water contain some form of virtualization of the outer universe they are contained in and can be used to simulate the variables of any other phenomenon in the nature inside or outside of that system albeit at different "speeds". As an amateur I can only vaguely express my thoughts, but I have this bet that the nature of the universe is in fact discreet and that by looking into the nature of "pure virtualization" is key. it is very logical to assume the universe itself another one of these virtualizations. A "pure virtualization" is a concept I came up with for a virtual machine that is described in a 100% machine-independent turing complete code. So for example writing an emulator for an X86 PC in ANSI C with absolutely zero reference to the original machine in a way that the emulated machine could in turn emulate itself using the exact same code thereby defining its own architecture from either a physical description (from without) or an abstract description (from within). Either way, it's impossible to tell which one is the "real" way to describe the virtualization. Both are correct because both are actually the same description relative to any other abstraction that lies above them in the hierarchy of virtualizations. So far my money is on a Universe that is a virtual machine with two fundamental operations "Instantiate" and "Null". One spawns itself and the other is nothing (or a hole if you will) and only through the two of them forming a progressing single-dimensional fractal graph pattern does time, space and information exist. The 'connections' talked about in LQG and other theories to me seem like these graph nodes, and waveform collapse is just the way our human VMs interpret the progression of this information. The progression of information on a graph being what we know as 'time'. The idea of gravitational pull comes from asking the question from our experiences of being pulled toward instead of understanding the universe as 'progression of information from the big bang'. Gravity is the result of regions of higher entropy in the mass category of abstractions. Electromagnetism is equally relativistic and follows the same principal. Example: Just because there's a shorter distance mass-connection wise from the anode to the cathode of a battery cell across the air, doesn't mean relative to an "electron" (I'm simplifying a quantum informational concept here, but you get the idea if you're following along) the metal wire is a shorter path - at least when we frame relativity in terms of 'relative to the big bang'. The kicker is that mass, electromagnetisms, and even the concept of > 1 dimension are actually abstractions defined by US as creatures of Earth/physical domain and are meaningless to the quantum soup that is the universe, but AS mentioned above it's still a valid description regardless of being defined from within us or from without the universe. I think a lot about this stuff and should have probably gone to school. Am I insane or am I a genius, I don't know. Someone give me an honorary degree or commit me please. I am fairly certain I am sane but that too just seem so relativistic when you've seen the things I've seen! I think I know what Turing and Von Neuman saw when they looked at this stuff and it's incredible.

@maximillianalexander7052

2 жыл бұрын

It’s so simple when you know it. Stop looking at matter and the space continuum as two seperate things. Look at mass as dense areas of the fabric of the space continuum. Then you will see that the greater the mass, or density of the space continuum, the greater the affect on what you call the space continuum. An affect that we observe as gravity. There is a reason matter warps the space continuum, because it is the space continuum… Einstein had it 80% correct, what he didn’t perceive was that matter and the space continuum was one and the same. Break matter down to its most fundamental unstable quantum particles, and it becomes or returns to the state of being that what you call the space continuum. If you take Einstein’s theories visual examples of a space continuum grid but instead of placing a Ball of matter on the grid to warp it, ‘fold’ a section or scrunch a section of a grid into a ball. It pulls or warps the grid area surrounding it, and effect of the pull on the grid becomes less the further away from the area of density or matter, you know the rest. When the Hadron collider smashes particles to find unstable quantum particles that ‘disappear’, where do you think they go? They break down into the space continuum. So where do they come from originally? Bingo, the space continuum. There’s a reason I don’t call it the space time continuum. Einstein’s calculations did not balance due the perceived dimension of time so he simple removed it by bundling it with space calling it spacetime continuum… some things only exist because the human mind conceives it too exist. Time is the largest optical illusion out there… the mind can be tricked by much smaller optical illusions, that’s all I’ll say on that. If anyone wants to chat about this or model it with me, hit me up.

@polycreativity

2 жыл бұрын

​@@maximillianalexander7052 yes, this is exactly how I see it. We can identify "holes" as "objects" but "objects" are really just an artifact of our mind. Some objects are "virtual" and yet still perceived, identified and treated as real objects. They don't truly exist, it's just a useful survival-oriented abstraction based on a few properties including change of density or optical properties. Humans have 3 perceptron's and so this density at large enough scales is perceived as a sphere that sucks things in, but from from the perspective of the universe it's doing nothing of the sort. We have a specific time-domain that we perceive but we can and often do make up time domains to create abstractions. Meter lines on a stick for example are an invented domain and if we count them one-two-three it's like casting from the meter stick's time domain to our own. Our time domain is based on interaction events, but the time domain most people think of is like a clock ticking - but that's only based on a convenient pocket of space where the clock happens to have an even tempo relative to our perception of it. In reality if you made a clock the size of the solar system it would not have such useful properties for us unless we too were that size.

"Notre-Dam" *snaps* Too soon. Too soon.

Just noticed that you're saying "Ashketar" instead of Ashtekar. Easy to do, I guess. :)

@anaywalunjkar

4 жыл бұрын

It's an Indian name, hard to pronounce I guess

@janpeternelj2309

4 жыл бұрын

Wait so Ashtekar is correct? That's the way it was written but he kept saying Ashketar.

@TraneFrancks

4 жыл бұрын

@@janpeternelj2309 As written is correct.

@yin-chengkrishuang8405

4 жыл бұрын

8:22 Ashtekar, not Ashketar.

@marsupius

3 жыл бұрын

Ash guitar

Could you do a Video about the big bounce theory and how it works without singularities? I've always wondered why the classic Theorys predict singularities. Couldn't there just be a point where the collapse stops, for example at the Planck length?

This is the first video I've actually had to rewatch. Wow thanks.

@berk6240

2 жыл бұрын

kzread.info/dash/bejne/hYyEz7SMeNeeZsY.html interview with Carlo rovelli, one of the founders of loop theory

The most promising idea nowadays in physics (in my opinion) is that gravity is an emergent property of quantum entanglement. Search keys are: 1) Raamsdonk, gravity, entanglement; 2) Susskind, ER=EPR.

@rschlesinger

4 жыл бұрын

I would add Sean Carrol, see his latest lectures on YT

@RazorBaze

4 жыл бұрын

@@rschlesinger thank you! Added in my todo list.

@falnica

4 жыл бұрын

I hadn't heard this, but if it's true, wow

@YourIdeologyIsDelusional

4 жыл бұрын

Leo Susskind is onboard with this idea?

@CharlesLaCour

4 жыл бұрын

@@falnica Basically from what I understand the amount of entanglement between volumes in Hilbert space (the complex space of the wave equation) can be used to define locality and from there define a metric for the shape of space/time. Also using this definition of distance ends up giving a connection to why the maximum entropy of a volume of space is proportional to the area of the surface surrounding that volume.

I like Matt's presentations. He is easy to understand, though he is delivering some seriously dense content. He doesn't talk like an auctioneer, nor like a teacher talking to a 7 year-old child. That's a terrific balance to strike. I don't claim to fully understand LQG after watching this, but I am quite surprised at how much I learned. I feel I have a basic understanding, enough for an amateur to be getting on with.

A deeper video on spin networks would be pretty cool

It seems to me that the big issue in fundamental theories of everything is in the limits of human conceptualization: To understand a theory, we need to base it on something, which takes the form of "holding" one concept in place and defining all other concepts by their relationship to the held concept. Relativity "holds" concepts of matter and energy in place to talk about space and time, while quantum mechanics "holds" the concepts of space and time in place to talk about matter and energy. The problem arises because a theory of everything, by its whole point, CAN'T "hold" any concepts in place, because then it wouldn't be describing that concept at a fundamental level; but a theory without any concepts held in place is missing the basis needed to relate concepts together. This is why String Theory and Loop Quantum Gravity both end up inventing new concepts (gravity loops, strings); they need some concept to be the basis on which to build everything else... but that just means there's a new concept that needs to be explained, and the theory isn't quite fundamental. There may be an argument to be made that an actual theory of everything, at least in a form comprehensible to us, is actually impossible.

@vvirgil153

4 жыл бұрын

I hope Matt sees this comment. Very logically reasonable to me.

Universe *slaps tummy* "It can fit many löps"

For those interested in gravity, I can whole heartedly recommend a book, Three Roads to Quantum Gravity, excellently written, and somehow makes complex topics understandable without losing (edited from "loosing") the depth of the material.

@upgrade1583

4 жыл бұрын

gravity is a side effect of mass, how can there be a whole book on it?

@Joemamahahahaha821

4 жыл бұрын

Upgrade are you kidding?

@dr.trotter1086

4 жыл бұрын

@@upgrade1583 There is sooooo much we don't know about gravity. Not only is there enough to write a book, there is enough to write entire libraries.

@scottrokeby4761

4 жыл бұрын

I read that book! Sooo good. For all we know of gravity its still such a mystery.

@scottrokeby4761

4 жыл бұрын

@@Joemamahahahaha821 I think Upgrade is a troll in training.

Great video! I have no idea what you just said, but you sounded good saying it

Fascinating. It's the best way to fall asleep.

"we live in a seriously Loopy space time" YES THIS 😂😂

@WackadoodleMalarkey

4 жыл бұрын

Apropo username 😸