Does Gravity Require Extra Dimensions?

3 роки тому

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It’s been 120 years since Henry Cavendish measured the gravitational constant with a pair of lead balls suspended by a wire. The fundamental nature of gravity still eludes our best minds - but those secrets may be revealed by turning back to the Cavendish experiment. That steampunk contraption may even reveal the existence of extra dimensions of space.
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Hosted by Matt O'Dowd
Written by Katie McCormick & Matt O'Dowd
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Executive Producers: Eric Brown & Andrew Kornhaber
End Credits Music by J.R.S. Schattenberg: / @jrsschattenberg
#space #astrophysics #gravity
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КОМЕНТАРІ: 2 700

@igortolstov487 3 роки тому

I love falling asleep to his calming voice without understanding squat of what he says

@aterfelis4708 3 роки тому

You are not alone. So many times I've wanted to make the same comment.

@jakefromstatefarm1405 3 роки тому

Same, physics bedtime stories

@pooyazadeh5066 3 роки тому

You hit the nail. I wanted to comment the same thing but was afraid it would be considered inappropriate.

@kachetofes 3 роки тому

Last 2 years i’ve been sleeping to this channel, i watch it out of interest as well, but there is no better asmr out there.

@LocalCryptidGhostdoll 3 роки тому

Damn dude same

@marlonrodney2457 2 роки тому

Cavendish's ability to actually measure the force of gravity remains one of the most unbelievable feats ever accomplished in physics to me. It is inconceivable that he could measure such a tiny force with such a mundane experimental set up.

@r-pupz7032 2 роки тому

Yeah it's mind-blowing, human scientific achievement at its finest! It's incredible looking back at how much scientists did without all the tech we have these days (not to diminish current scientists, it's just very cool to look back at things like the Cavendish experiment!)

@JR-playlists 2 роки тому

Maybe when you get two materials so close to each other, not only does gravity affect the measurement, but the other nuclear forces at the molecular level might affect the measurement results?

@jamesmnguyen 2 роки тому

@@JR-playlists Strong And Weak forces only act at atomic scales, Weak force's range is fractions the width of proton. Still a problem if we use this experiment to measure gravity though.

@inverse2k1 2 роки тому

@@JR-playlists no, the nuclear forces won't. The Casimir force, however, will.

@igotufoinformation9636 Рік тому

@vikramgupta2326 3 роки тому

That's pretty damn amazing he made such a precise measurement in the early 18th century.....it does feel like we're chasing ghosts with these extra dimensions.

@decro4945 7 місяців тому

It is the best route we have currently though

@oinkyoinkoink1879 3 роки тому

Thank you for clearing up the multiverse thing. I've been telling people that the double slit experiment is incredibly misunderstood for a while now.

@norasheffield8036 3 роки тому

I am 55 years old and have long aspired to study astrophysics. You have inspired me to return to college and attain a degree! I love your shows and thank you for your excellent explanations.

@charlesheyen6151 3 роки тому

Best of luck to you!

@warrend.tateiv112 3 роки тому

I wish I had the means to return to school to study astrophysics myself. Good luck!

@aaaaaa-qn8ol 3 роки тому

Well done! Enjoy your studies :)

@aaaaaa-qn8ol 3 роки тому

@@warrend.tateiv112 try an online course?

@donaldsmith3926 3 роки тому

@@warrend.tateiv112 Many of the starter courses, at least, are available w/o cost online.

@unvergebeneid 3 роки тому

Since the weak nuclear force is often just called "the weak force," I think we should colloquially call gravity "the puny force."

@juancarlosp.f9519 3 роки тому

Agreed

@MrRolnicek 3 роки тому

I don't know ... I don't think I can call it a puny force for as long as I live on a planet from which I can't jump into orbit using my own legs.

@navinsingh1730 3 роки тому

@@MrRolnicek Same. The biggest strength of gravity is that it adds up on infinite scale

@timo4258 3 роки тому

@@MrRolnicek it's not that gravity isn't puny. It's that you are puny compared to that. (Its not a burn, we all are punier than puny)

@TheExoplanetsChannel 3 роки тому

@lmelior 3 роки тому

"At least I can live vicariously through the superior wit of the brilliant Dr. Poopstick." - Matt O'Dowd

@jmitterii2 3 роки тому

All hail Dr. Poopstick! If only that was a real name and that person with that name came up with a unified theory of Quantum mechanics and Relativity; the new Euclid, Newton, Einstein, etc. kitchen table name would be Poopstick. Our adventure into idiocracy would be beyond the event horizon, inescapable. But would it be that idiotic if such a unified field theory provided insights into our questions about black holes and dark matter and energy? If Dr. Poopstick's unified theory reveals working understanding of the universe that leads to applications that propels to at least the K1 or K2 civilization, maybe it wouldn't be the same type of dumb idiocracy. Yet if what such a unified field theory reveals is those things behave idiotically up to and including providing no possible useful application to advance technology. Dr. Poopstick reveals our universe is idiotic and useless. :( On the bright side, it would help solve much of Fermi's Paradox.

@phillipkennedy3444 3 роки тому

@@jmitterii2 hahahahahahaha lmfao that was brilliant thanks for the laugh i like the way you think

@VictorCaldo 3 роки тому

Is it possible for a high-school physics teacher to perform the Cavendish-Michell experiment or some version of it with meaningful results? This would have been phenomenal to understand in my earlier studies, and of course, very inspirational.

@jarrlist7424 8 місяців тому

2:27 2:27 2:28 2:29 2:30

@rodrigoserafim8834 3 роки тому

Newton had the brains, but Cavendish had the balls.

@johnboze 3 роки тому

Newton was right about kinetic energy. Total KE is not equal to 1/2mv^2. Newton proved KE is mv^2, just like E = mc^2. Einstein was no genius when it came to KE. Newton had it right all the time. But half the energy goes into the angular momentum of the Bożeons, the Elementary Particle of the EM Field, the electromagnetic dipoles of EM Fields, spin faster around in the derived particle like a photon. "The Principles of Nature: Bożeon Flows, Density Gradients, and Orientation" will begin to “Make Things As Right as Rain, Drop, Drop Top”. 2020 "The Year of the Revelation in Reality": All things are kinetic, not magic. BRAVE's "Basic Tenets of Nature" are as follows: [1] ALL FORCES ARE LOCAL (local momentum transfer from elastic collisions only, period), [2] YOU CANNOT BEND SPACE, and [3] YOU CANNOT BEND TIME, and [4] YOU CAN BEND SPACE AND TIME IF YOU ARE “DR. STRANGE” or “DR.WHO”. Unify All Theories Now: BRAVE - Bożeon Research and Æther Verification Eταιρεία. Copyright 2020 John E. Boze

@avidnongetit8710 3 роки тому

Gross...are you certain..or just referring currently accepted biological norms...hmmm

@mickey4125 3 роки тому

Don't worry man I caught your joke and heartily enjoyed it! I worry about the two commenters above though...

@TorToroPorco 3 роки тому

And Einstein had the ladies. Which I’m sure stimulated both his brains and his spheres. guardianlv.com/2015/06/albert-einstein-was-a-ladies-man/

@rodrigoserafim8834 3 роки тому

@@TorToroPorco Nothing like a woman to help you see everything in relative terms and change your frame of reference... every other morning.

@jamesbeale4451 3 роки тому

The fact that "the weak force is 10^24 times stronger than gravity" gave me the opportunity to explain powers of 10 to my 11 year old son. I want everyone to understand the gravity of this situation.

@Robert_McGarry_Poems 3 роки тому

Orders of magnitude, that's heavy stuff.

@jamesbeale4451 3 роки тому

Woops! Had to edit post. My daughter just pointed out that her brother is not 13 (she is); he's only 11. Apparently I was too busy thinking about big numbers to remember small (but important) ones. D'oh!

@semaj_5022 3 роки тому

@@jamesbeale4451 ouch. Haha

@Tubluer 3 роки тому

Well well well.... that number is much exaggerated . Remember that in general relativity, all physicists are subject to hyperbole. Of revolution. Which sucks.

@RecoveryHacker 3 роки тому

This comment doesn't really force anyone to like it, just curves the likelyhood that one will wave off any doubts to the importance of math.

@federicobrennittelli188 3 роки тому

Matt you’re a movie star. You my friend are featured in the movie The Mandela Effect @ about 17:40 seconds! Add that to you’re already awesome resume!

@danielengland5 3 роки тому

I actually understood the majority of the information presented in the video. Usually I get confused about 1 minute in. Thanks for making the content easy to understand!

@mariem6605 Рік тому

Bravo for listening even though you don't understand. Knowledge is a puzzle and we need all peace's to understand big picture😃

@janeadelaidelennox7193 3 роки тому

“Gravity is, by far, the most familiar of the 4 fundamental forces” - every drunk person ever

@rb3872 3 роки тому

Scar tissue on my knee from my childhood means that that quote could have been from any child as well ;)

@jesserramsessoller990 3 роки тому

What's the 4th? Havent they united electromagnetism and weak force and created electroweak? So we have gravity, strong, electroweak and....?

@spindoctor6385 3 роки тому

@@juancarloscastro8270 Congratulations, That was almost a sentence. I applaud you for giving a second language a try. Keep at it, you will get there.

@EyeOfThePhi 3 роки тому

I've been drunk 😎

@EyeOfThePhi 3 роки тому

@@spindoctor6385 racist 🤬

@logan_wolf 3 роки тому

16:24 "At least I can live through the vicarious wit of the brilliant Dr. Poopstick." Well, that's something I never thought I'd hear you say.

@paulmitchell4876 3 роки тому

How did he not laugh while saying this hahaha

@robertocapocchi8379 2 роки тому

I caught myself admiring the painting again, and I remembered your earlier comments about it. Thank you for that extra element of extraordinary humanity and beauty. Your exemplary eloquence is only surpassed by your good taste.

@briansmithbeta 3 роки тому

I cannot pinpoint exactly what was different about it, but this episode seemed to represent a stepwise quality increase in the script and visual presentation above the already fantastic baseline quality this channel has long established. If you know what you did different, keep doing it! If not, try to identify a difference in your process before it becomes too distant in time to do so. I feel like this entire episode was a masterpiece. Thank you for consistently producing such amazing content.

@Foneio 2 роки тому

agreed!

@albevanhanoy 3 роки тому

"Space... Space... Space... Time" Clever.

@Robert_McGarry_Poems 3 роки тому

Space³ * Time¹

@marcpeterson1092 3 роки тому

At first I thought he had missed his tag line. I had to go back and watch it again before I realized he just said it differently.

@yuvalne 3 роки тому

He's getting cleverer by the video

@Pheatrix 3 роки тому

Comment to the answer on broken math: "All models are wrong, but some of them are useful." George Box

@johnboze 3 роки тому

Relativity is completely wrong for the right reasons. But it is does model the Vacuum Energy in the Galactic Realm very well. But illegal on atomic scales. Which is why it is only a model and not a good theory. But there is value to the model because it accurately predicts vacuum energy somewhere. So we learn why and fix the model. Still waiting.

@avg_user-dd2yb 3 роки тому

@@johnboze same thought curved space sounds silly.

@thelikkhaparishe 3 роки тому

I came across this quote on a statistics class. But this quote does better job than anything else at reminding me in physics the math is a mere model and why there are many bizzare models out there.

@DaKILLaGod 3 роки тому

shall the nobel prizes be returned for works which will be false after a real theorem will come up?

@bobimus 3 роки тому

I don’t know but there is something weird about assuming 3D space in extra dimensions. Compactification is used to visualize math which doesn’t seem useful outside of a pie chart. These universe models are just models of math. What is the point of visualizing math and saying that’s the universe? You want a 3D model of the universe and all the dimensions that come with it, go grab a telescope.

@StevieObieYT 2 роки тому

Now It’s been 122 years since the Cavendish experiment. And it's just as impressive today, as it was back then. What a legend! 😏

@Rockool52 2 роки тому

It's been 222 years.

@ilkoderez601 3 роки тому

I've been a Space Time fan for years and this episode and the last episode are so wonderful. Bravo!

@jarehelt 3 роки тому

I love how you put up equations and diagrams. And you dont dumb down the physics like other channels. I also love how you respond to comments at the end of the video. Best channel ever you deserve a whole planets worth of subscribers

@antonystringfellow5152 3 роки тому

If you want more science channels that aren't dumbed down, try Sabine Hossenfelder and especially Sean Carroll.

@starfishsystems 3 роки тому

I also like how carefully he adds qualifications to the simplified description, so we don't just try to apply it uncritically.

@carysgilbert4938 3 роки тому

Honestly the "Spacetime" pun at the end of each video is the only thing keeping me going through this tough (space)time

@dpearson80808 3 роки тому

And when you know it’s coming but you still love it when it happens. And the pause before “in the farthest reaches..........of Spacetime”

@WhatsNextVideos 3 роки тому

I just discovered this channel and I have to say WOW! Thank you Matt for blowing my mind!

@dutchflats 3 роки тому

Love the physics your videos explore and the way in which you present them. Nice work, please continue on.

@biereauxfruitsrouges 3 роки тому

I would love to see this space time city and it's population: half lost weed smokers, half skilled scientists. This would be true peace.

@CyberSway 3 роки тому

Lost weed smoker here, any skilled scientists around?

@TheWmham 3 роки тому

Why are those two mutually exclusive? Ha

@johnkeith8072 3 роки тому

@@TheWmham They aren't...

@tisroc100 3 роки тому

the show is really perfect stoner fodder

@Robert_McGarry_Poems 3 роки тому

Yes, and Oregon is one of the perfect places to be. I can walk into a store and buy some over the counter, no jail time....

@Ariemius 3 роки тому

Just thought I would put out that black holes were originally thought to be artifacts of math as well, so chasing down where the math leads is one of the best ways of understanding our universe or others found traveling through a rotating black hole.

@EazymoneyBicch 2 роки тому

I just wanna say I'm addicted to this channel. Been watching it every chance I get for the past 2 weeks!!! Remember, knowledge is power and the more u know the better

@coder0xff 3 роки тому

Congrats Matt, and PBS Space Time! I'm proud to be a supporter of this excellent channel.

@leobritton8929 3 роки тому

THAT casual flat earth debunk was so classy. 😍

@rupakrokade 3 роки тому

Excellent observation.

@hans-joachimbierwirth4727 3 роки тому

Some need their fruits hanging even lower than usual to look classy.

@PaskalS 3 роки тому

Actually it was more about 2D space, which is not the same as the flat Earth.

@Orangaria 3 роки тому

This channel is part of the reason I just applied for university in physic. I hope to work on theories of subatomic particles someday. Thanks for the amazing content

@ltdowney 3 роки тому

"If you could put the universe into a tube, you'd end up with a very long tube. Uh... probably extending twice the size of the universe. Because, when you collapse the universe, it expands. And, uh, you wouldn't want to put it into a tube."

@photondance 3 роки тому

It’s not a bowl.😐

@ashleystewart34ify 3 роки тому

People say to me, “Donna, you get so wrapped up in the physics of it, don’t you have any fun” And I say I go outside and I look at the big dipster, and the little dipster...

@Littlejacka33 3 роки тому

I just read that there are new discoveries on Omuamua this week. I would love to see you do a video on these new findings. It's also nice that the new information doesn't seem to be claiming aliens without proper evidence again.

@felipemonteiro5877 3 роки тому

John Michell should be mentioned more often. Thank you for remembering him.

@NewMessage 3 роки тому

"It doesn't seem to gel with the other forces..." I can relate.. I'm the black sheep in my family too. You just do you, Gravity.

@harry_page 3 роки тому

Absolute mood right here

@TheExoplanetsChannel 3 роки тому

Hehe

@141Zero 3 роки тому

Are you also 10^24 times weaker than your little brother?

@FireFiend 3 роки тому

LOL

@stephenbonutto2713 3 роки тому

Phhh .... no wonder our young forces are growing up so sensitive these days .. Gravity needs to learn to stand on its own 2 feet ... pay its way ... get a mortgage .. adult forces things

@akira1228 3 роки тому

PBS Spacetime, Vsauce and Eugene Khutoryansky are my favourite science channels on english YT. Thank you for making great videos and congratulations reaching the 2m subs ;)

@platypuspracticus2 2 роки тому

It's so curious that we exist in this and observe and measure it. Literally the only physical process that measures and documents other physical processes. It's like we're a debugging software in the process of initially mapping out the program.

@loturzelrestaurant Рік тому

THOUGHTPROVOKING CHANNEL for EVERYONE: 'Some More News' (especially the videos about Work and Unions, which allll who ever worked or want to work should watch 3 times) and 'Second Thought' (especially when talking about Socialism and the Stigma on the WORD).

@alexanderheld2200 3 роки тому

I love how a physics video is on the frontpage of youtube within 38 seconds after its release 😍

@kaidenschmidt157 3 роки тому

How do you mean? Your recommended or?

@chimmiebomb 3 роки тому

You mean your recommended feed? That’s tailored to every individual person. Unless you mean the trending page but that’s not possible

@jefflayton4339 3 роки тому

It only took their algorithm 0.00034 seconds for it to decide your tastes for you.

@The.Incredible.Mister.E 3 роки тому

@@jefflayton4339 if only the algorithm gave this video to flat earthers...

@Feynman.R 3 роки тому

I think you misunderstand how UKposts work.

@luudest 3 роки тому

0:00 Actually it has been over 220 years since the experiment of Cavendish (not 120) On my metric Space Time is still the most entertaining and accurate show in history.

@dlevi67 3 роки тому

222 - results published in 1798 (only posting this because 222 is a nice number)

@jimtroeltsch5998 3 роки тому

Sure, alright then. Dork.

@jonasgrnbek7113 3 роки тому

@@jimtroeltsch5998 What an aggresive answer lol

@garrettwarren3523 3 роки тому

Yeah that confused me at first I was telling myself that the 18th century felt longer ago than 120 years haha

@Samael1113 3 роки тому

Yeah, I thought so.... he said 120 years, then later said late 18th century and I was like "The math doesn't add up there, unless we've solved the Einstein-Rosen-Podolski Bridge"

@goober685 3 роки тому

Thank you to Matt and all of the folks behind the scenes. You guys keep blowing my mind. Lol

@Tiago211287 3 роки тому

Excellent explanation! I wish I had access to this material 20 years ago!

@h7opolo 3 роки тому

2:30 thank you for explaining why the rule of thumb for gravity's rate of declining effect is equal to a denominator being raised by the power of exactly two.

@h7opolo 3 роки тому

aka inverse square law's validity

@andreafois1654 3 роки тому

best "space time" ending in the history of this channel imo.

@Lucasukx 3 роки тому

You deserve the subscribers! Terrifically made and presented videos. Well done!

@flake8382 9 місяців тому

I had not heard of Cavendish' experiment until now. What a genius exploit of engineering to achieve such a brilliant and clear outcome!

@PaulJohnson-zv3hl 3 роки тому

My favourite part of Space Time is Matt reading the usernames so casually in responses “So Polygonwanaland” 😂

@SirArthurTheGreat 3 роки тому

Well he’s from the same country as King Gizz

@chaz000006 3 роки тому

Dr. Poopstick !

@chrispicable 3 роки тому

Polygondwanaland is a great science-mashup username though

@zoadanoise9454 3 роки тому

go listen to it. it's a perfect album by king gizzard and the lizard wizard

@MarcDrt71 3 роки тому

Imagine how many Harry Crack they are weeding out....

@FunkyDexter 3 роки тому

Wouldn't extra dimensions affect electromagnetism, since that also follows a square law?

@mitchwilson1969 3 роки тому

Just what I was thinking. Why only gravity?

@tetraedri_1834 3 роки тому

If I remember correctly, string theory predicts that gravity is the only force being diluted in the extra dimensions. This has something to do with gravitons being closed strings (like rubber bands) and other force-carrying particles being open strings (like guitar strings) attached to the large 3-space(time) from their ends. The gravitons thus can move freely in these extra dimensions, while other particles only vibrate in them. EDIT: Let me add a disclaimer: I'm not very familiar with string theory, so take what I say with a grain of salt.

@FengXingFengXing 3 роки тому

I think very high energy gamma ray can get inside small extra dimension. Flat land people can use sound, light and gravity for test if other dimension exist.

@HermanWillems 3 роки тому

Yes, maxwell equitions fit perfectly in the kaluza-klein theory. Look it up.

@starscape539 3 роки тому

According to his past video (How to Detect Extra Dimensions) which Matt references at 4:33, the reason that physicists don't think extra dimensions affect electromagnetism is that it is not weak among the 4 fundamental forces. Electromagnetism, weak nuclear force, and strong nuclear force are much stronger than gravity (ukposts.info/have/v-deo/a3iKq2yth4hq0ok.html) . So they are trying to find a reason to explain that relative weakness by testing whether additional dimensions are sapping the force of gravity as it moves through them in addition to our existing 3 spatial dimensions and causing that relative weakness.

@evanmcc2000 3 роки тому

This part reminded me of people who more than not catch falling objects suddenly. Spacial awareness seems to sometimes usurp the eye hand response time over gravity. Could be micro anomalies within spacial awareness.

@rjonboy7608 3 роки тому

This is excellent. Best I've spent time recently. 👍

@cmfrtbly_nmb 3 роки тому

Thank you for always putting out great content. You have a way of explaining really deep and complex topics in an interesting and digestible way. Keep up the great work!

@RecoveryHacker 3 роки тому

Dr. Brian Greene was discussing this during one of his Daily Equation Livestreams. One possibility that he explored was that gravity may not be a fundamental force at all, but an emergent property. This is one of the most fascinating topics currently being explored!

@ahumanperson3649 3 роки тому

XY ZW that sounds like a bunch of bunk to me, but you’re entitled to your opinion.

@jaredstokes9895 3 роки тому

Height, width, depth, & mass

@tekrunner987 3 роки тому

@XY ZW 2020 was such an interesting year. We got covid and also the first Nobel prize of physics awarded for a youtube comment. What a year.

@espaciohexadimencionalsern3668 3 роки тому

light refracted from the systems electromagnetism creates gravity. MATTER just falls into 2 mayor groups(gaseous and rocky) and at the center they form a disc that has both charges so planets practicly float in the systems as we do in the solar system.

@mrEofPlanetEarth 3 роки тому

XY ZW: I have a crazy explanation of Gravity! Espacio Hexadimencional Serna: Hold my tin foil hat!

@bobinthewest8559 3 місяці тому

For some time now, I’ve (loosely/intuitively) hypothesized that gravity is the only one of the forces that is “dispersed” across “all” of the dimensions… while the other forces, only really “interact with” our four known dimensions. Due to this, what we refer to as “dark” (matter and/or energy), is simply “dark” because it exists within those other dimensions which we are (at present) still unable to perceive. Interesting to hear a very similar concept mentioned in this video. I’m excited to hear more in the future, regarding development of this idea, what we will learn, how this “pans out”, etc.

@schmetterling4477 2 місяці тому

Sounds good... until you do a few experiments and then it completely collapses. :-)

@arias1321 3 роки тому

I have study spacetime and the possible dimensions in the universe. I have concluded that there are 11 dimensions we can observe in the universe. I've been trying to organize then to explain to the people how they work and what they are! But the most important find is what time is. Time is what gives dimensions the imaginary view of them! I hope soon to explain to humanity what time is, and what is not, so we can change everything in the near future, forever!

@breezyx976 3 роки тому

People: Rick and Morty is a very complicated show, it actually takes a large IQ to understand the humour People who watch pbs spacetime:

@craigwall9536 3 роки тому

You spelled "humor" with a "u" and are therefore irrelevant.

@YoJoof 3 роки тому

no one says that rick and morty takes higher intellectual skills to understand they’re basically talking bullshit the whole time, nothing complicated

@AnneDank69420 3 роки тому

@skOsH you're just being boring, with extra steps

@mickey4125 3 роки тому

@@craigwall9536 Humour *is* spelt with a u. Or it was, before those thrice-damned colonies butchered our perfect, far superior language.

@physicsboi1744 3 роки тому

@@craigwall9536 it depends on the country, if ur brittish or aussie then humor is spelt with a "u".

@MediusMajere 3 роки тому

I might not always understand what you're saying. That being said I love how you explain complex things! Never stop!

@cvp5882 Рік тому

If gravity is "diluted" by compactified dimensions, what would that imply about the proportion of force that holds galaxies together? Would that increase the apparent amount of dark matter, since it implies gravity is less influential on cosmic scales? Either way, I am confused and/or intrigued lol

@czarlguitarl 2 роки тому

I love these!!! Breathes life into sci fi concepts that I enjoy

@victorbruant389 3 роки тому

It only needs a bookshelf and the ability to morse S.T.A.Y.

@andikahetris5219 3 роки тому

oh now I kinda understand interstellar..

@TheExoplanetsChannel 3 роки тому

Yes

@voyager60091 3 роки тому

Could you please help me understand the reference

@Metal73Mike 3 роки тому

"We should like all hang out sometime"... man, would that be some interesting party :-)

@thecraftingmax 3 роки тому

I've always loved the idea of higher spacial dimensions and everything that comes with them, but at the same time I've never found the existence of higher or lower spacial dimensions plausible because of a simple kind of logic experiment that comes to my mind whenever I try to visualize a lower dimension object. It goes as follows: Imagine a cube, you see 3 dimensions, x, y and z. Now reduce one of the dimensions gradually until it reaches zero so you are left with a square, but wait, if you remove one dimension completely, the object just disappears, it has zero volume, and it's a fact that an object needs volume to exist so therefore 2d universes and 2d objects aren't possible. Now, if we assume there are 4 spacial dimensions, then the same would happen with our 3d universe, the simple existence of a fourth dimension would mean that our 3d universe isn't possible, but here we are, in a 3d universe. The way I find that a lower dimension would exist is if it does have all the dimensions, but they are at the lowest unit of measurement they can be, like for example: a 2d object would be 12 cm x 10cm x 1 electron (or even quark). But then the object wouldn't truly be two-dimensional, and if a 4th dimension existed then our universe wouldn't really be three-dimensional, but from what this video is telling us, our universe is in fact three-dimensional so therefore a 4th dimension doesn't exist. (Hope what i just wrote make sense, I'm not a native English speaker)

@seewithouteyes 3 роки тому

😲 I loved ur explanation....that does make sense

@ronmullick253 3 роки тому

You say"and it's a fact that an object needs volume to exist so therefore 2d universes and 2d objects aren't possible." Well in a 2d universe objects need only area to exist and not volume.Because in a 2d universe volume will be an alien concept. So in the Flat Land story,when a sphere shows up in the Flat land,the Flatlanders see it as a circle.And when the sphere passes through the 2d flat land,the Flatlanders think of him as a very clever circle that can make it self very small down to a point and even less.Because Flatlanders cannot perceive volume.

@brianr6661 2 роки тому

This video just casually destroyed what I thought I understood about different dimensions. I am very interested in learning more about how we have made Cavindish's experiment more sensitive aside from placing it in a vacuum and temperature controls. I am more curious about the construction of the mechanism itself.

@VaradMahashabde 3 роки тому

0:07 Matt says "Wah"

@kingpet 3 роки тому

"Waiah"

@TheoEvian 3 роки тому

@@kingpet Actually he exhibits a kind of merger that weakens possible triphtongs like in "fire" "cure" or "wire" into long monophtongs which are typical for the wider English family of dialects (which Scottish and Irish english are not part of so no, there is no such a thing as British English, really, that is a polyphyletic grouping). So "fire" is pronounced almost like "far" and "cure" almost like "kyoh". I have already forgotten name of this shift but it is relatively recent.

@caruzo9631 3 роки тому

why-urr

@OverseerXIII 3 роки тому

*wario intensifies*

@discovermajid 3 роки тому

I was searching the comments to see if somebody else picked up on this. WAAA

@NewMessage 3 роки тому

"No one says Space Time City is a democracy..." Well... A Benevolent Dictatorship worked for Ankh-Morpork...

@TheExoplanetsChannel 3 роки тому

Wow

@abinx- 3 роки тому

If u are a bot

@FairchildTom 3 роки тому

I was about to say unexpected disc world reference but then I remembered what channel I'm on

@christianheichel 3 роки тому

Well they had more pork of course it would work

@cshairydude 3 роки тому

@@christianheichel So much they even had warehouses for pork futures. Full of ghostly carcasses that didn't quite exist yet.

@juandavidgilwiedman3490 3 роки тому

Hey guys. Just dropped by to tell you the amazing content you guys produce... Great story teller to illustrate the realms of reality.

@1985tris1 3 роки тому

Brilliant video. I hope you don't mind i will show my students (CIE A levels) some sections as next month we need to go through the section of gravity. Also it is always a challenge to get students believe that we don't yet fully know everything and are still learning. Your explanation or the R squared inverse is brilliant with the graphics as well as the way you present the method of determining the G constant so long ago. Thank you fellow Aussie and PBS.

@momokireitenshi 3 роки тому

His explanation for the inverse R squared makes sense, but I don't get why that would scale up to other higher dimensions when we can't measure any as it is and we don't know what the geometry of extra-dimensional gravity waves if they even exist.

@xxxx85 3 роки тому

All hail Mayor Christina! :D Seriously though, thanks to everyone donating!

@lalala13131315 3 роки тому

I’d love that city honestly 🙌🏻 full science and nerds everywhere

@miv366 3 роки тому

Where all the parties would be kind of lectures

@davburns 3 роки тому

@@miv366 Sure, but they'd be the kind of lectures where someone always asks, "What is the specific gravity of ethanol?" and someone else knows the answer off the top of their head.

@aldenconsolver3428 3 роки тому

I started to ask who would do the work - then I remembered how when I was doing my undergrad I had an assembly line job at night and did my best learning there, those furnaces kept my hands busy and my mind wandered around over a good solid 90 billion light years. When I had to memorize something I would write it on a 3X5 and prop it up on a machine, learning one formula at a time all night.

@cadosian078 3 роки тому

I’d like to see the population of SpaceTime City at the end of each video, like a live feed of sorts, but for the current time which it was recorded. I thank you for increasing the science literacy in the world, Matt.

@sandro7 3 роки тому

That would be awesome, I'm really dying to know if we managed to pass Multan

@davidmladenov2926 3 роки тому

Watching this, I really appreciated the elaboration that the inverse square law "scales" as we reduce or increase the dimensions. While not a full explanation, I thought that a nice way to describe the intuition behind this change in "power law" is that the R is in fact, an element of a single particular dimension - the first! So it may well appear that the law itself changes *in reference* to that "linear" distance R. The theory and evidence remains the same - just a way to think about it, like dragging a linear function up or down.

@erawanpencil 7 місяців тому

It seems a lot more 'natural' that there would be fractal (inter)dimensions at varying scales, rather than the very manmade idea of 8 tidy dimensions in string theory or the like.

@ASLUHLUHCE 3 роки тому

4:32 It did not rule out the possibility of extra spatial dimensions! It only ruled out extra dimensions where gravity is leaking into them. It doesn't say anything about extra spatial dimensions that aren't doing anything to gravity or light.

@michaelsommers2356 3 роки тому

Who said otherwise?

@aether3885 2 роки тому

@@michaelsommers2356 He literally did, right at the part Anonymous time stamped. He first says our dimension probably isn't folded into a higher dimension in the way the 2nd dimension is into the third, gives the caveat that it's only for spacially "extra large" dimensions, and then he finally says extra spacial dimensions aren't likely either. I love this channel but some of the conclusions are drawn a little too confidently for the foundation they're standing on. We can only observe phenomena spacially in the third dimension, but that doesn't mean there are no spacial dimensions above it. It's a failure to recognize the limits of our perspective. Science finds information that forces working models to be completely reworked pretty regularly, you'd think we'd have figured out by now to be less certain about the uncertain

@michaelsommers2356 2 роки тому

@@aether3885 It's been a year or more since my comment, and I don't remember what the video was about, so I won't comment.

@Catalyst375 3 роки тому

"Causality is more fundamental than time". "Gravity is just time curving into space. Time is more fundamental than gravity." - The Science Asylum

@johnreder8167 3 роки тому

true. very simplified though. Nick is definitely one of the best science vloggers out there.

@RichardWilkin 3 роки тому

15:11 "The quality of the predictions of any model depend on the assumptions that go into it." Although not an original statement, nicely said.

@apophenic_ 2 роки тому

You guys are amazing. Thanks for everything you do.

@undertow2142 3 роки тому

Thinking about the Casimir effect. If two metal plates “exclude” the quantum vacuum. Then what effect does a planets worth of mass do? Doesn’t mass also exclude the quantum field? So why isn’t gravity the result of a quantum vaccuum being compressed by things with mass?

@totallynotme8153 3 роки тому

”If you ask 3 questions in a comment or more, you’re an alcoholic” - Dr. Ken Jeong

@OrechTV 3 роки тому

I was thinking about this: "I know there is probably reason why this idea is not the case but HERE IT IS anyway: What if gravity originates in these small dimensions = pulling mass "in" / "around the point" .. like black hole but in our dimensions it is just pulling force without "event horizon" because it is not in our dimensions. Now, if every particle works like this, of course the more you go from the centre of mass, the weaker it is but since it is "pulled by force" does not it mean these "islands" of mass (and gravity) in space are just pulling itself to its "core" = other dimensions = basically like a black hole which STRETCHES the space for each of them. That is why space is accelarating all the galaxies which can pull each other will stick and the space between these islands of gravity will further with added space and time "create" force whcih basically stretches them apart (because of bending space in their region) ...and I think the accelaration is not even equal across the universe so this may be the case. I would check for any corralation in this (amount of gravity within region of space vs. expansion of space in that direction with all the mass along the trajectory of the observer) ... just put this all on comparison for the effects of what we see and call dark energy" .. can you hit me up on gmail ? Would like to talk about your view and probably explain it in more detail :/ .. Idk much about the concepts so please correct me :D

@jasexavier 3 роки тому

It's an interesting idea, and I had to think about it for a bit, but I don't think it would work. This wouldn't predict a force proportional to mass, but rather determined primarily by surface area. Also, plates of equal mass don't exhibit the same Casimir effect if they are made from different materials. The plates must be conductive for the effect to be observable. So glass plates and copper plates, which experience identical gravitational forces, would experience different forces from the Casimir effect. A compressive force *might* make sense for e.g. a planet holding itself together, but why then is the earth attracted to the sun? The Casimir effect only appears when things are extremely close together. At even an inch apart the effect is negligible. Certainly at 90 million miles it wouldn't do much.

@xxACIDVIRUSxx 3 роки тому

New video, he’ll yeah I’m ready to get my mind blown away by trying to understand some of what he says.

@sunny-sq6ci 3 роки тому

story short: we still have no idea how the universe is the way it is cuz our tiny squishy brains have yet to evolve further.

@TheExoplanetsChannel 3 роки тому

Yes !

@Ariemius 3 роки тому

I'm so glad that I'm not the only one who looks forward to this headache lol.

@agimasoschandir 3 роки тому

@@sunny-sq6ci The sum of our knowledge is the result of many gelatin brains, not one squishy one

@kindlin 3 роки тому

This video was one of the more digestible ones in recent weeks, or months.

@tomasgarza1249 Рік тому

Woah, back when I was still at the university, I remember coding a simulation of gravity and I used newton's law, but the simulation was 2D, and objects were attracting each other extremely fast, and I would see extrange behaviors like planets orbiting near one another, but escaping with greater speed than their original speed, but when I got rid of the square, the simulation seemed more correct, and I never understood why until now.

@fernandotanase114 3 роки тому

VIDEO REQUEST: How exactly does gravity affect time

@callummcleish5281 3 роки тому

T=0

@siddharthverma1249 3 роки тому

Imagine being able to measure something so precisely 220 years back!

@momokireitenshi 3 роки тому

It's frustrated me since seeing "How to Detect Extra Dimensions" I don't see how we would be able to use the gravity wave to discount dimensions beyond our 3 physical dimension. First, I'm guessing we are assuming that the gravity waves originated at a single point in any dimension, but I don't know how we would know that's true without being able to make measurements in any extra dimensions which is a bit of a causal loop (why would we need to prove extra dimensions if we can already measure them). Second, there seems to be an assumption that the proportionality of gravity to radius would be measurable in an extra dimension without a measure in that dimension (see previous causal loop). As my attempt for an explanation, when looking at your arrow example of dispersion of gravitational force in three-dimensions the arrows spread in each direction equally, therefore, the arrows in any two-dimensional "slice" of the three-dimensional diagram will still only spread at a rate proportional to the radius regardless of being in a three-dimensional model. Likewise, the arrows spread in four or more dimensions would still spread at a radius squared rate without an extradimensional measurement. More simply, the circumference of a growing sphere at any single fixed dimension will grow proportionately to the radius, and the same should apply regardless of how many dimensions we apply (i.e. the change in circumference of an n-dimensional sphere will be proportional to the change in the radius) and as we go up in dimensions this will still hold true (ie for growing sphere an N-dimensional sphere the change in any [N-x]-dimensional measurement will be proportional to the change of the radius to [N-x] power)

@jjharvathh 3 роки тому

Also, if there are extra dimensions, some of those may not be "friendly" to gravity, that is, gravity is not existing there in those others. We would say that dimension is orthogonal to gravity.

@momokireitenshi 3 роки тому

@@jjharvathh Yeah, we don't know the extradimensional geometry of gravity. I didn't specifically say that before, but that kinda what I meant when talking about assuming a point source (ie assuming a spherical geometry)

@vickyprabhat 3 роки тому

Yeah.. So how do you explain when the body is 2D and the gravity arrows are only circular and not spherical.

@momokireitenshi 3 роки тому

@@vickyprabhat The simple explanation is that the 2D body is the same thing as a 2D slice of the 3D body. A 2D slice of a 3D sphere is a circle.

@momokireitenshi 3 роки тому

@@vickyprabhat a real life way to show this would be to blow a balloon up a little then draw a circle around it not necessarily around the center. Continue to blow up the balloon, what happens to the circumference of the circle? It goes up proportional to the radius (C~r) because it is a 2d measurement, but the surface area goes up proportional to the square of the radius (A~r^2) because it is a 3d measurement. Shouldn't the same happen as more dimensions are added?

@venelinpetrov6811 3 роки тому

Matt, you should make a video about you and your colleagues. This channel is the best thing in UKposts and we would like to know more about the people who are making this wonderful content

@TheSaleemrashid 3 роки тому

What a pleasant surprise to hear from you about the city of Multan which is not very far from my own city in Pakistan!

@OnlyKaerius 3 роки тому

I've always thought of the curvature of spacetime caused by gravity to be in an extra dimension, but not a regular spatial one, more like an extra-spatial dimension.

@kritisahu5347 3 роки тому

Same.

@phildiop8248 3 роки тому

Yeah same

@beri4138 3 роки тому

You're wrong though. Gravity bends the 4-dimensional space-time you're living in.

@BigB1Lachi 3 роки тому

This reminds me of an idea I once had that gravity wasn't a force itself, but only the probability of a particle being close enough that the strong force would act upon it.

@solapowsj25 3 роки тому

Same here. Gravity is a region that accepts motion due to force. If not, the force would not produce motion. The North ferromagnetic pole would repel another North and attract the South pole. The positive terminal would drain current only to the respective negative terminal of the same system. And a type of graviton would be the region where linear oscillatory force gets displaced into.

@christophepatou1764 Рік тому

From my Last reading on holographic theory, The quantum gravity is expressed by (here for the proton mass) : Mp=2*Q*ml ml =planck mass Q is the gravitationnal ratio - Q= qty plancks on surface/qty plank in the volum for all spherical body. -with a plank sphere used in volum calculation and the planck spherical équatorial surface used for the surface area calculation For à proton : Q=10^-20 Mp=10^-24 g Q is the holographic gravitationnal ratio, à ratio between the surface entropy and the volum entropy. (Quantized by planck units) This solved also the hiérarchic problem between proton and planck mass. With only geometrical values and planck mass

@perlindholm4129 3 роки тому

Experiment - The staircase test with the phone gravity noise meter. Create a testset with different elevation and a gravity data for each step. Classify with a machine learning model if you can predict which data belongs to each step at the elevation.

@lazymillennialjobseeker9282 3 роки тому

What if every “dimension” in string theory referred to a different conserved quantity at every point in spacetime (for example, an “energy” space, momentum space, a quantum information space, etc.) On a less “Facebook comment on a fail-tier pop-sci blog” note, how are dimensions defined on this level?

@ericvilas 3 роки тому

you're actually right about that, sort of - movement along the 4 "extended" dimensions is related to conservation of momentum and energy (space and time respectively), and the original Kaluza-Klein theory essentially just did the same for electric charge - it had one extra dimension where movement around that new dimension would be related to conservation of charge. Quantum information seems to be another thing entirely, I think. Don't know enough about the subject tho...

@lazymillennialjobseeker9282 3 роки тому

Eric Vilas Oh, so dimensions are a kind of Noether theorem thing? At least as far I understand the concept.

@Joiner113 3 роки тому

I don't think quantum information is quantifiable in the same way as other forces.

@timh.6872 3 роки тому

Well, there's a certain aspect of this that has to be useful, since the Pauli exclusion principle and the existence of neutron stara shows that "momentum space" is a "real" thing, allowing multiple fermions to instantaneously occupy the same spatial location (distribution? absolute locations and fermions don't exactly work well together), as long as they have different coordinates in momenum space. Given that momentum is the fourier transform of position (in terms of the wave function), momentum is conserved under spatial translation symmetry, and energy and time seem to have a similar gauge symmetry/conservation, I'd expect that time and energy have some similar Fourier transform relationship. Likewise, multiplying momentum by velocity gives units of energy, while multiplying duration/time by velocity gives units of displacement/position. I wonder if those momentum/energy dimensions are "stretchy", expanding as necessary to keep track of all the particles, changing how gravity behaves in highly populated space.

@Robert_McGarry_Poems 3 роки тому

The term information is only useful to physicists. The things that happen, happen whether we isolate and label them or not. So, to say that information has a dimension would be meta-physical, in the mind. Compartmentalization, it could actually be more of a definition problem than an observation problem. Words and shared language fail to be as divisible as the natural world. A lack of information...so to speak.

@NeroThacher 3 роки тому

"Space...Space...Space.....Time" Oh no! Matt's having a stroke!

@voges1001 3 роки тому

No but seriously he seems off

@RlrOfWorldzYT 3 роки тому

He's just being creative about ending every episode with the word spacetime

@heisag 3 роки тому

Spacetime(height), spacetime(width) and spacetime(length). And yes, i am trolling.

@TheResiDogs520 3 роки тому

I had always been interested in science as a kid but when I read Brian Greene's ELEGANT UNIVERSE as an adult, I was hooked on physics. This show gives me that same feeling of excitement and wonder. I turn 40 on Wednesday and finish my 2nd semester of college the following week. My goal is a bachelors in Engineering and see where that takes me. This was the first time I heard of the Cavendish experiment and it made me appreciate our grasp on the fundamental laws of gravity that much more.

@AynenMakino 3 роки тому

I was just thinking about the gravity problem a few days ago. One thing that came to mind is the idea that everything in our universe seems attracted to everything else by however tiny amount, no matter the distance. This presents a problem: If gravity diminishes based on how much area it covers, eventually you reach the planck unit of energy. Either beyond this point there is no energy left to gravity, or it continues indefinitely as 1 planck energy or gravity. If it's the former, then gravity should not be able to reach every other bit of mass in the universe. If the latter, that implies infinite energy. What's up with that?

@ilikephysics2232 3 роки тому

I always thought about gravity like this: If gravity is just stretching the sheet of spacetime, and if a sheet in 2d is being stretched into the 3rd dimension, then our 3rd world would be stretched into the 4th dimension.

@briandiehl9257 3 роки тому

Unfortunately I don't think that's actually how that works

@gavinhatch5483 3 роки тому

I actually think it would shrink

@Robert_McGarry_Poems 3 роки тому

If your mind has no functional imagery to visualize what you mean by pressing into the fourth dimension, then most likely you are still just imagining the 2d sheet warping into the third dimension. As stated above, that is not helpful outside of early learning. What does 3d space warping look like?

@Gunandrunandgun 3 роки тому

@@Robert_McGarry_Poems ... like gravity?

@muffntheB 3 роки тому

gravity isnt stretching a sheet, thats too simplistic and 2d, gravity is collecting and bunching up spacetime all around us like a cocoon

@FengXingFengXing 3 роки тому

Why graviton particle can not enter extra mini dimension then come out again? It come out some place else, and cause gravity become weak faster? Any experiment show lose sub atomic particle and appear some place else? If no, then dimension smaller than any observed subatomic particle.

@jasexavier 3 роки тому

The expectation is that these dimension are smaller than particles, or at least the smallest space you can confine a particle to by the uncertainty principle. There is (was?) an experiment at the LHC attempting to make black holes, smaller than any particle, which would only be able to exist if there were those tiny rolled up dimensions.

@peter4210 3 роки тому

brave of you to assume there is a gravity particle

@FengXingFengXing 3 роки тому

@@peter4210Crazyer idea: tiny quantum black hole

@peter4210 3 роки тому

@@FengXingFengXing The craziest thing I have heard is dark energy/matter. You can't beat a theory about a theory

@edquinn7135 3 роки тому

No such thing as a graviton partical.

@cehson 3 роки тому

Thank you guys for your awesome work !

@timmykenny717 3 роки тому

It would be really interesting to have maps of galaxies that filtered out particles going at different speeds. A picture of a galaxy seeing only the particles that are going at or very very near the speed of light and different maps for the particles that are scaling down in speed. I guess it would have to be a computer simulation cuz if it was a picture we would only see from our perspective but still

@r7diego 3 роки тому

12:18 that ending tho ! Genious ! This is by far the best channel on Yotube

@merlin4real 3 роки тому

Is it possable that at the big bang most matter created was sent this direction through time, and most antimatter was sent along an opposite but parallel timeline, creating a parallel universe with an opposite charge? Would it then be possable that black holes "portal" matter to the other universe, obliterating most of it? Would there be evidence of antimatter being sent our way at the same time if this were the case?

@espaciohexadimencionalsern3668 3 роки тому

When a system gets broken the north side(lighter matter) goes to one side and the heavier matter goes to the oposite, this hapens in the slit experiment so one side of the bars is positive and the other half is negative and at the medle of both mut to be white, the limit of bars in a system are 7, that is 3 negative and 3 positive and white at the medle, some other may appear but those are disperse matter out of range.

@espaciohexadimencionalsern3668 3 роки тому

In atraction opposite does not means against but tendensy to atract.

@josephcrozier7782 2 роки тому

Perhaps black holes are an example of splitting one or more normally compactified dimensions apart. Could explain the intense / odd gravitational affects at small scales near the event horizon of a given black hole?