Gravitational Waves Work Like This Drill on Spandex

I take a classic demonstration of warping spacetime and figure out how to demonstrate gravitational waves with the addition of some wheels and a drill.
Discussion video about LIGO and gravitational waves:
• Gravitational waves ex...
Tom Scott's video about frame rate:
• Why Does Nighttime Sma...
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[@thoperSought]

that explanation of how you did the slow-mo with the stroboscopic effect at the end was nearly as amazing as the demo itself. I think I loved every single thing about this video

[@ZoeSoutter]

nearly 666 likes!

[@Leo1239150]

ThoperSought also the reason we have 25 and 50 fps cameras and in the US they have 30 and 60 is pretty amazing. (It's about lighting)

[@MrNikki426]

I agree.

[@neilfisher1944]

I agree. I’m guessing this is the reason car wheels on tv look like they are going backwards

[@ElizabethSwims]

You should put a planet in that universe while you run the drill and see what effect it has.

[@dhruvinvekariya975]

It will also oscillate beacuse it is also in that space(here lycra) fabric:)

[@9WEAVER9]

General Relativity necessitates 3 spatial and one temporal dimensions for the existence of gravitational waves.

[@electricpaisy6045]

I guess it's hard to do that with a suitable size since black holes are extremely heavy in comparisson to planets.

[@billcraig5614]

@@9WEAVER9 go ahead and make you 3 dimensional lycra tutorial then. For someone who is trying to sound intelligent you seem to miss the simplest understanding of what his intent with this video is. I wouldn't apply for any patent clerk jobs if I were you.

[@CrazyFlyingMonk]

@@billcraig5614 bro i get it and people who seem to forget the fact that these are supposed to be simplified so as to be easily understood are annoying but more annoying are people who go around being incredibly rude on the internet for no good reason e.g. you

[@Lorenzo-ke2vr]

That demonstration of the stroboscopic effect was a gem inside a gem, I loved how those two topics merged together perfectly!

[@zurri6513]

Not only gravitational waves, by pressing your finger there you also visually demonstrate that energy is mass.

[@aidanenglish5475]

This is rad

[@akasin8202]

Woah..

[@Chris-it4fe]

Zurri thank you

[@tusharjamwal]

How? I didn't get that bit, could you please explain?

[@SuperTauta]

@@tusharjamwalIt takes energy to modify the shape of the fabric (pressing down again the "springiness" of the lycra)

[@RealEngineering]

Fantastic work Steve!

[@schregen]

Real Engineering I support this statement in every way, shape or form! 🍄💋🍄💋

[@calencrawford2195]

Gravity is the warping of space-time...the only thing your leaving out is that fact that it's 3-d.

[@irfaank3257]

Which fabric u used to in the above explanation

[@digitallfax]

I’m going to be completely honest you this guy practical engineering The backyard scientist and maybe some others I don’t really know working on a single project would be the most glorious thing of KZbin science seriously imagine a giant route Goldberg machine (i’m not sure if I typed it right or I got a completely wrong name but you know domino effect) just made from a bunch of chemical reactions complete mechanical genius and so many other things I don’t have time to name would be amazing seriously just imagine a humungous gas can popping starting up a clockwork on one side of a chemical process on the other and it just continues for like 25 m or so with pieces intentionally breaking for a glorious effect and the you (Aka real engineering) you could make a Animation oh what’s going on on the inside and practical engineering could also work as a secondary voice actor and if you ever do this please give me credit at least a small bit or something I just wanna see this you could have me in the background like a small piece of text or something but please do this it will be glorious bye

[@moonlandingagain3228]

No

[@djimavicpro4kvideologangro754]

I guess you could say these are going wheely, wheely fast...

[@beactivebehappy9894]

When is this comment gonna published as a quote on the Ellen show!??

[@franchufranchu119]

Take my upvote and leave

[@casseylayca6078]

I'd like ur comment but I'd break the 69 likes, someone else can do that

[@rottenapple2276]

Fuck yku

[@aerolchristopherinfante]

Lmao

[@reginabedgood1799]

When you are so smart that you don't even need a high speed camera to do a demonstration of gravitational waves. Goals. Here from Smarter Every Day! This was a great video to recommend to get people hooked on your channel!

[@ThePanacronic]

Here from "Which Way Will the Water Go? - Smarter Every Day 226" Excited to see what your channel has to offer.

[@logicalfalse]

If you drew a black 'L' on the fabric you would be able to fully demonstrate the LIGO setup since the weave within the fabric would stretch in an analogous way to space-time base on the amplitude and direction of the wave. Neat.

[@Mernom]

The observatory is closer to a very uneven cross.

[@EMETRL]

@@Mernom yes but what they were testing were the oscillations observed where the two lasers meet in the intersection. So in terms of what ligo really cared about, the L is what's important.

[@Ritefita]

YES or to draw a planet

[@Ritefita]

@@official-obama fabric "is" space-time. L is alike the real shape of LIGO (nice!!!!) warping space-time causes distances in L to change. That's what they measured.

[@Ritefita]

I said "draw a planet" but L - is a craaazy idea!

[@shelvacu]

I think I liked the details at the end of how you did it the best :D

[@quantiplex]

Definitely takes some skill and thinking to be that resourceful. Great work, Steve!

[@dymt1662]

I had already learned much about gravitational waves; loved the demonstration! But the details at the end is where I learned something new, thanks!

[@aaronr.9644]

Same here. It was pretty clever.

[@odw32]

What I took away from it is that faster-than-light travel is easy. You just tighten the fabric of your universe.

[@FullOnGritz]

Funny that you mention that. If you were to "tighten" the fabric of your universe by stretching it out then you are actually also increasing the distance between point A and B on the fabric relative to this overhead view. Meaning it would take information the same amount of time to travel that distance even though it would appear to propagate faster overall. That is a great example of how relativity and the speed of light interact that I never thought of before reading this comment. Thanks for that! :)

[@GoalOrientedLifting]

These types of videos are the reason I love this channel. You explain something really technical in a semi-simple way. The speed of fabric and the trick with the camera was like a hidden Easter egg of physics.

[@davidb4509]

That was super cool. I love your method of capturing the “slow motion” wave propagation without a slow motion camera. It made me think of how when you record the rim spinning on a car, as the car accelerates the rim appears to go through cycles of slowing down until it stops and then reversing in direction. Plus, the visual aid is awesome. Thanks! I came here from Smarter Everyday and you’ve earned my subscription. 👍

[@jayray314]

Yeah if you like Smarter Everyday and Steve Mould you should look up Stuff Made Here, Practical Engineering, Jake Owen, Lesics, Animagraphs, and The B1M. I promise they won't disappoint!

[@mattcay]

I love how you became 'the guy that pours stuff out of beakers' as you put it and also fully embraced it :D Can't wait for the second Mould effect :)

[@Twitchi]

That bit at the end was pure in joke gold :D

[@davicho2988]

Twitchi ni

[@dyscea]

maciej53 thanks. Wanted to make sure that's what he meant. Even funnier if only a small group gets it.

[@SallyLePage]

What a fab demonstration! Plus I'm glad you described all the work that went into calculating how to get it to work - I would never have guessed how accurate you needed to be!

[@SteveMould]

The main thing is that if you spin too slow the wavelength is too long so you can't see it and if it's too fast the fabric bunches up (and you have to match it to your camera!). Love your channel by the way!

[@blitzv10]

+Steve Mould this is the best way I've seen for people to visualize and make sense of gravitational waves great job!

[@BillySugger1965]

No wonder I haven't been seeing your posts Sally, for some reason I was no longer subscribed. I just guessed you were busy doing other things. Fixed!

[@Ampersand100]

@@SteveMould So is the bunching up of the fabric a way to visualize *why* the speed of light is a speed limit? Great video.

[@SteveMould]

@@Ampersand100 interesting idea! I'll need to give that some thought.

[@benaycock1646]

The smug look on his face when he says “I then tightened the fabric on the frame to speed up the speed of light in my universe to get it to the speed I needed it to be” 😂😂what a bad ass

[@Omega0202]

If you can't beat the speed of light, just tighten the fabric of reality to your liking!

[@ebybbob]

Really really cool work. I hope educators are incorporating this into their own demonstrations. Thank you!

[@BurakBagdatli]

I wish I could give this video a million likes.

[@praveenb9048]

There a limit on the speed of likes.

[@DaffyDaffyDaffy33322]

Don't have a high speed camera? Increase the speed of light in the universe! I just love the sentiment of that. Great work :)

[@SteveMould]

By stretching the fabric of space :)

[@X0verXDriveX]

Destin sent me here. The fact that you found this out on your own is mind blowing and deserves my subscription.

[@danielarmstrong4290]

Hello Steve, I just came from your video with Smarter Every Day and I immensely enjoyed this video! I also thought it was so cool how you said your eventual goal was 1 million subscribers in the SED video and when i clicked on your channel to watch this video you had 1.01 Million subscribers! Congratulations! Thank you for the work you put into your videos and for helping to share knowledge.

[@PINGPONGROCKSBRAH]

When you put Tau times the radius on the screen, I got a warm fuzzy feeling inside.

[@ncghost12]

Yes.

[@HYPERPLASMATIER]

Vihart, Yay!

[@ultragamer4465]

FILTHY TAU BIRGIN < GENIUS PI CHAD

[@ultragamer4465]

@@ncghost12 No

[@tenebrisoc9808]

@@ultragamer4465 Tau is superior. Down with pi.

[@brandoncalvert8379]

quickly becoming one of the most exciting creators to see in my subscription box! you thought of so much to get this to work, like changing the "speed of light" of your universe based on frame rate of your camera. i love it :)

[@SteveMould]

+Brandon Calvert thanks Brandon!

[@mjashishletsrock]

Amazing work sir, this is the best representation of gravitational waves I have seen so far

[@DeclanMBrennan]

Only seeing this now. What a beautiful demo. The waves look so clean and I loved the way you used the stroboscopic effect instead of splashing out on an expensive high speed camera. Brains trump money (nearly) every time.

[@JohnnyYenn]

By far the best visualisation of gravitational waves I have seen so far! Awesome :D

[@NorbertHarrer]

Fantastic video. It contains so much information and is still easy to understand. Really really well done.

[@SteveMould]

+Norbert Harrer thank you!

[@simongreve]

Your newest video linked to this video, and now this video is linking to a previous video, the rabbit hole never ends!

[@esphilee]

Absolutely clever. Best illustration I have seen about gravitational wave.

[@sevfx]

5:26 the casual tau-dropping xD

[@chrisbovington9607]

I found you through Tom Scott's channel. I love that you used tau in your calculation. The whole vid was very interesting and well made. Definitely sub-worthy.

[@SteveMould]

+Chris Bovington thank you!

[@SteveMould]

+mrbandishbhoir glad you could see past my deviant ways!

[@Megalomaniakaal]

I don't understand people who dislike the τ just as I can't understand the people who dislike the π, the two work best together!

[@simongregory9453]

JellyGamer that's actually really interesting, never heard of that before

[@mbohon1]

What a beautiful demonstration! I've struggled to understand how gravity waves arise, and now I see! Thank you!

[@abhishekrayasam9065]

This was an excellent demostration. I literally feel that I'm watching the black holes colliding with each other.

[@samanthausman4151]

This is currently being circulated around the LIGO collaboration for being an awesome representation of gravitational waves

[@SteveMould]

+Samantha Usman amazing!

[@frostchain2362]

Coming to watch this 2 years later, I just noticed that you can see the effects of rolling shutter on the rotating jig 6:17

[@chrisparkin499]

Awesome demonstration. So clear, and the photography explanation was very informative too. Great video!

[@Posesso]

Pretty f good. I like how you take care saying right things, in a complete way, without too many words .

[@willland387]

Awesome - glad Destin did a Video with you. I’m subscribed

[@maximecloutier1223]

2:14 That's some sneaky editing :p

[@narisenbara5117]

This is my first time understanding gravitational waves. Phenomenal demonstration.

[@baivulcho]

Amazing video! You could learn as much physics, or even more, by the explanation how you filmed it in the end. Great job!

[@gamesgreenz5878]

Cool demo!

[@heheheheheeho]

Did you say "Thirty million meters" and changed your voice in post? Sounded like something like that at least

[@SteveMould]

+tokfrans yes I did. Well spotted!

[@Jimpozcan]

2:12

[@Megalomaniakaal]

Three hundred million?

[@stuffstuffing296]

honestly it startled me

[@BLCJ123]

I came into the comment section to see if anyone else noticed lol

[@DanHarkless_Halloween_YTPs_etc]

Wow. Absolutely brilliant. You are amazingly gifted at demonstrating and explaining scientific phenomena in an easily understandable way. And holy cow, we got a great tutorial on using the stroboscopic effect to replace a high-speed camera, as a _bonus?_ Amazing.

[@pauldogon4831]

What an elegant and simple apparatus to explain a concept, nice one Steve

[@AgglomeratiProduzioni]

The fake slowmo is brilliant!

[@gurdanetas]

Great video! I had seen you on Numberphile before but I really like this channel! Glad to see it's growing!

[@SteveMould]

+Gilberto Urdaneta thanks!

[@amodgawade4323]

the stroboscopic effect at the end was very cool!!!!! and the demonstration was amazing as well, awesome!!!!!

[@ceruleanwake8876]

Oh my gosh! Thank you so much for explaining all the stuff at the end about the frame rate and the spinning speed! Thats soo interesting!!

[@MagisterMalleus]

The stroboscopic effect you described is how "femtophotography" works, is it not?

[@rich1051414]

The main difference is it's two dimensional instead of three, so the waves are actually spherical.

[@Royvan7]

would they be tho? they are still rotating about an axis. wouldn't it be more cylindrical-ish?

[@olbluelips]

Royvan7 No because they radiate equally in all directions

[@Royvan7]

@@olbluelips ic thx

[@josephwesward]

Yet, spiral

[@ErisApplebottom]

That was 3 dimensional, wasnt it? I mean the fabric is sort of a 2d plane. But the waves made the fabric raise above and below the plane into the 3rd dimension. Are you just saying the waves would be taller than his representation?

[@TDGalea]

It's absolutely amazing how clear that came through without a slow-mo camera.

[@Asdayasman]

Technology Connections' videos on PAL vs NTSC are the most thorough I've ever seen.

[@Dani0x1B]

I subscribed to this channel as soon as I saw tau used instead of pi.

[@SteveMould]

+Daniel Escoz yes!

[@deca0]

Anyone notice that fly looking thing get yeeted off the tarp at 8:57?

[@kieranwalker2249]

Not me lol it’s funny tho

[@brianflud4739]

If you are the first person to do this you deserve some kind of prize or something. Way cool.

[@901EE]

Well Done! I visited the LIGO observatory at Richland a few months ago. Most fascinating!

[@sebbes333]

5:32 *I now have additional questions:* * What happens if you spin that thing faster than the speed of light in your rubber-universe? * And what difference does it make if you spin it much faster vs slightly faster than speed of light? example: instead of spinning 18 times/second you do 20 times/second (as slightly faster) and then like 60+ times/second (as much faster)? * And does something special happens when you spin it at a multiple of t the speed of light (like harmonic frequencies?) so: 2x Speed of light & 3x speed of light? is it similar patterns?

[@tchgs11zdok15]

I think he probably did while he was using that drill, also i believe it would just create a much higher frequency waves (tho I'm not an expert and I haven't tried it)

[@omsingharjit]

I think it was uncalculated speed by drill may be faster

[@appelslice]

He will end up with a torn rubber sheet 😁

[@Royvan7]

just guessing so take it with a grain of salt. the 'speed of light' in his universe was the wave propagation speed. so, if he exceeded it he would be out running the waves. so, either the sheet can't keep up and stuff starts to get tangled or something like a sonic boom happens. namely the wave starts to get "jump" discontinuities. he actually might have been going faster the wave front was quite a sharp drop.

[@PeterMilanovski]

Well you can already see the reflected waves returning from the edges causing harmonic distortions, if you continue to speed up the rotation of the drill, you will end up at a resonant frequency response to which you will begin to see the whole surface vibrating in a particular pattern...

[@deepfriedsquirrel]

As a physics graduate that was an awesome video, definitely going to share to friends and family. Is that a new scientific musical instrument at the end?

[@SteveMould]

Thanks! The bit at the end is just a stupid reference to the fact that most of my videos feature me ouring things out of a pot.

[@MohdAradi]

I am watching your video laying down on the exact same bed/chair that is behind you in the video probably half way across the planet, or maybe only a quarter if you are in England. simply amazing.

[@qfourr]

Awesome video! I liked both the intuition on GWs and the explanation at the end

[@Jeroen_Ech]

Don't we now have the chance to see what happens when you move stuff faster than the speed of light? I wanna see that. Would you get something similar to a sonic boom? A reality boom?

[@special-delivery]

JeroenEch That is some really good imagination :) but traveling faster than light is a physical impossibility as far as Einstein confirmed. The main reason is that time is undefined if you're traveling at the speed of light. So the idea of traveling faster is a no-no. There's a video from vsauce explaining what we would "see" IF we traveled at the speed of light. Maybe you can check that out.

[@Gribbo9999]

JeroenEch A photonic boom. As in "launch the photon torpedos Mr Sulu."

[@theblackwidower]

I think we saw that actually. If you'll notice sometimes the waves are really sharp, which I think is where the drill moves faster than the speed of sheet. The little casters start colliding with the waves themselves.

[@MarioFanGamer659]

Cherenkov radiation is what happens if you go faster then light. Of course, it is because light travels slower inside a medium but hey, that is after all, a light equalivent of a sonic boom.

[@tardonator]

JeroenEch that actually does happen: www.iflscience.com/physics/ultrafast-camera-caught-light-doing-a-sonic-boom/ in the experiment however, they lowered the speed of light in a similar way to how light travels slower through glass than it does in a vacuum (this speed difference actually causes refraction you see in glass and water)

[@atifyasir5790]

I just want to meet those people who can dislike such a video. I think if someone brought a real-ass black hole and put it in their backyard, they wouldn't probably be amazed. And for the video and the demonstration that was provided with it, man you just blew my mind with the simplicity of it.

[@praveenb9048]

I think they are robots with a random bug in their algorithm.

[@ronindroid]

The explanation stroboscopic effect and how you modified the "speed of light" is a really interesting bonus!

[@nazrulislam-ol8wt]

Your videos are always so much ingenious, always makes my eyes wide open while watching your video . And also ,you have a very beautiful way of explaining things . Thanks brother. For this video

[@xLucy_Hx]

Sub coming atcha from Smarter Every Day. Glad you did the collab :D

[@Smoke1]

Bet in the future you'll get Gravitational waves sonar, where gravity telescopes/spaceships fire off gravity waves and detect reflections in order to to see/map large areas of space.

[@x-iso]

sure, just deploy enormous laser interferometers and juggle some black holes in your ship :D

[@alecwhatshisname5170]

x.iso it doesn't really need to be black holes, it just needs to be sufficient weight being spun at sufficient speeds.

[@x-iso]

well if the source is nearby, then maybe something less than a neutron star would do.

[@95spades]

well, it would not be very plausible as you would require enormous mass to make it work, and at monstrous speeds at that which in turn means even more mass as you need more gravity to hold the rotating objects together as they go faster (elsewise they'll reach escape velocity and so on). It's better to use light to measure distance and shapes where sound can not be used.

[@kevinburbank5564]

Amazing video and beautiful footage.

[@erikfranke8637]

You just earned my subscription my men! That was absolutely amazing and I totally hyped out about it!

[@syborg64]

5:27 I was about to say but wait you have to double the radius first, then I realized: Tau. Yes, thank you! I love tau and i'm ashamed I didn't notice it immediately

[@AmeDayo]

Put a marble on it to demonstrate how things can be affected, and because I think it will look cool.

[@tchgs11zdok15]

Great idea

[@wakyjedi]

or the large metal ball

[@nori8675]

Would that work with the stroboscopic effect?

[@Photosounder]

@@nori8675 No

[@anantdhanuka1604]

The last thing about the slow mo was great dude loved that and the explanation of gravitational waves was ausome.

[@lynk5902]

5:43 Thank you so much for not cutting this out Steve!

[@sysghost]

So I've learned that this man warps space-time with his fingertip.

[@mk_rexx]

( ͡° ͜ʖ ͡°)

[@straight-outta-jutta]

You do as well! Just really really gently

[@Mischkovonik]

5:27 that use of tau, though :D

[@billrussell3955]

I did love watching the waves wrap around the edge!

[@geckoman1011]

I’m glad these old videos are being suggested again

[@CaptainQwazCaz]

2:15 *speech.exe has stopped working*

[@washingtonjopir1024]

Hello got this channel link from smarter everyday

[@lajoswinkler]

Excellent demonstration and proper explanation. Well done!

[@Abhishek-qs4kl]

Simply Awesome...Man, you are highly underrated. May you grow soon and fast.

[@LawnD4rt]

Great video. Do you think it's possible to find a way to "ride the wave" as a means of propulsion?

[@CharlesRoels]

:-) he increased the speed of light.

[@user-zi8jn1go8k]

wow this visualisation is exceptionally good!

[@bojassem12]

I love how you and your wife come up with this idea together during the discussion you had!

[@DaScribbler]

Stroboscopic effect! Awesome, TIL. That must be what causes propellers and car tires to look like they've stopped or spun backwards

[@mwaskiewicz6531]

Steve, have you tried spinning the wheels faster than the "speed of light" of this universe?

[@h3ctic504]

God, that's what I was thinking! I really wanna know what it looks like!

[@SayedHamidFatimi]

absolutely loved this video, and your channel

[@richardteychenne3950]

Steve I take my hat off to your excellent clear presentation

[@danthibodeau8549]

Here because of Destin!

[@tomholton235]

Missed opportunity to refer to it as the speed of lycra 😁

[@rikeshchouhan5026]

I liked the explanation and the real world demo conception. Great work.

[@jasondashney]

That is some amazingly high quality fabric. It's stretching and retracting incredibly fast if you look at each wheel.

[@NimithChanceson]

If we can detect the reflected g waves than can we find the edge of the universe?

[@dreggory82]

I don't think there is an edge. But even if there was it would be such an incredibly weak signal, it would probably be buried in noise.

[@sombojoe]

I’m here after being “Smarter Every Day”! Are you?

[@nakishaki]

Yup!

[@rholyoak]

Yep.

[@philipshumway9943]

Here!

[@derickcronje5497]

Yass

[@duroxkilo]

i'm still on the SED channel, just buffering this baby up :} cheers everyone!

[@4Leka]

This is an amazing demo!

[@conorfitzpatrickdesign9616]

That alt slomo technique was SO COOL ! Thanks for the explanation

[@MichaelBeck_profile]

The poor fly (or bug) got kicked out of the universe by the gravitational waves ^^

[@BoildownAH]

If light and gravity travel at the "speed of light" aka the speed limit of the universe, then does the same thing that slows down the speed of light slow down the speed of gravity? I.e. the speed of light in an atmosphere is slower than the speed of light in a vacuum, the speed of light in diamond is 2.42 times slower than the speed of light in a vacuum, etc. Governed by the index of refraction. So getting to my question, do gravity waves propagate slower through matter than through empty space?

[@SteveMould]

+BoildownAH I'd like to know the answer to this too. Will do some research.

[@sharanbanagiri8343]

No, light slows down because it interacts with the atoms and molecules in a medium. Gravitational waves don't. The reason both have the same speed in vaccum is because the graviton, the hypothetical quantum particle of gravity is massless just like the photon

[@Nighthunter006]

Light travels slower in air/water essentially because it interacts with the molecules and refracts. In a nutshell, the light travels at the same speed, but it travels further because it keeps needing to change direction as it bumps into things. Light always travels at the same speed, but water/air is like a bunch of obstacles that it has to go around. That makes the travel longer, hence why light seems to, at a human scale, travel slower in air/water.

[@anselmschueler]

The speed of light doesn't change in different materials. The speed of a light beam/light burst changes. Sane here, the sog doesn't change, but it gets distorted and deflected by the particles in the way. But light is slowed down because of something different!

[@anselmschueler]

Actually, while we're on the topic, I just *have* to link to this *great" video explaining that phenomenon: kzbin.info/www/bejne/o3qmhYmlrJhgaas

[@andyjohnson4907]

How have I missed this channel? Amazing stuff!

[@CharlesCarlsonC3]

Great work Steve!