Did Usain Bolt REALLY run 100m in 9.63 seconds?

Usain Bolt won gold in the 100m sprint at the London Olympics, clocking 9.63 seconds... but Albert Einstein has something to say about all this?
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[@xcver]

man Usain really has a precise watch

[@ethanlinquist4525]

must be atomic

[@MajkaSrajka]

So do the stadium to compare results.

[@scottlapier4363]

How he chooses to spend his money is his business

[@msavri]

xcver i know like it goes instead of 9.63 it goes to 9.62999999999999...

[@sebastianhine8213]

Wonder what time he got when he ran 9.58s in the 100m

[@aghaanantyab]

HAHAHAHAHAHAHAH LOL!!! if you are arrested by police, and he ask you "do you know how fast you drive?". so we simply answer "relative to whos clock?"

[@idlingdove]

***** Clever! I like it!

[@NickMan2769]

***** i don't get it

[@NickMan2769]

wait, will I understand when I am finished watching breaking bad

[@NickMan2769]

***** Oh! I get it now thanks. The main character in breaking bad goes by the name of Heisenberg so I just asumed it was him. thanks for explaining.

[@simonbanks5012]

***** Turns out the original Heisenberg cooked up math theory, not meth deary...

[@howtoby27]

2:20 Angry Hitler?

[@cameronhanton7383]

lol this made me laugh😂

[@aidanteall7186]

howtoby27 mein furghur

[@Auzcast]

exactly what I was thinking lol

[@bartmeijer4573]

howtoby27 you made my day sir

[@FcBarcelonaKid]

lol nice one

[@sweatfootm]

My interpretation is that Bolt won in a relativistic sense, not because his time was shorter, but because he made the track shorter than all the other runners by moving at a velocity closer to the speed of light.

[@basabghosh7644]

Yep I it is also a factor the reduce the time

[@noyes4168]

The time dilation and length contraction is so small to the point where it is almost negligible and usain was going at a very small speed compared to light speed

[@slutskystheorem15912]

@@noyes4168 r/whoosh

[@Bean-Time]

@@basabghosh7644 basab ghosh

[@Bean-Time]

@@slutskystheorem15912 shaumil kjana

[@waldsteiger]

does this take into account whether the track is set up so athlets run with the turning of the earth or against it?

[@numberphile]

+waldsteiger I like your style

[@ryanpatterson1403]

+waldsteiger *realization kicking in*

[@OriginalNotFunny]

+waldsteiger how about make it perpendicular to the earth rotation?

[@gioschrijver5683]

Was about to that :)

[@HoNUrkiN]

+waldsteiger It doesn't matter, because the stadium is also turning in the same direction in the same velocity.

[@Wipez]

After watching this video, the olympics should get out a 15cm ruler and draw a line to mark exactly the extra distance the athletes need to run. Let's hope no athletes run the 100m and then stop before realising that they actually needed to continue running an extra .00000000000000000001 more of an inch to not be disqualified. I swear this comment isn't sarcastic.

[@blaze2672]

+WiPeZzOuTz most atheletes run significantly over the line. They would take away a world record if we had equipment that could measure it, but oh well, we can't.

[@raymondzheng2125]

They dont stop or slow down until they pass the line to get the best results

[@Wipez]

Raymond Zheng If you think atheletes can run 100m and stop before before they run an extra fraction of an inch, then you might be overestimating them ;) Yes I know

[@raymondzheng2125]

I think u reply to the wrong person read what I said

[@Wipez]

Raymond Zheng Oops yeah you're right *****

[@benshiffman7765]

"Take his medal away from him" if you can catch him 😂

[@mardy3732]

I don't think Bolt's watch would have displayed 15 decimals.

[@orielsy]

and I think that's not the point.

[@djamelrostom]

The point is that the stadiums clock doesn't display 15 decimals !!! also, nein, it will probably still be 9.63sec

[@cpad007]

There is no clock in existence that can measure to that resolution so this is all theory until it can be explicitly measured. :o)

[@orielsy]

Guys when astronauts return from spending time on the ISS their clocks are all out of sync with that of people on Earth. This isn't theory. Moving or being closer/further from mass (in our case Earth) affects the amount of time that passes for us. You can look it up. Our satellites have to be fixed every so often because their clocks run different from those on Earth.

[@levvillanueva6037]

+cpad007 I just got an app from Play Store with 20 decimals of a second

[@MyOwnConfessions]

I don't think people get what the video is trying to prove...

[@arttuhintsala9717]

Phillip Yang they surely do but thats not what they came for

[@angelmendez-rivera351]

Arttu Hintsala Nah, the comments prove otherwise

[@hydraxhcr2202]

Then explain please im 9 and i dont understand

[@-.._.-_...-_.._-..__..._.-.-.-]

People are taking this video way too seriously.

[@eoghan.5003]

Or maybe you're taking their comments too seriously

[@tyraster8603]

@@eoghan.5003 * looks at 8.4k dislikes * No, I don't think he is.

[@proloycodes]

@@tyraster8603 *looks at 0 dislikes* yes i do think he is

[@IntergalacticPotato]

@@proloycodes *looks at chrome add-on to show dislikes* or maybe he isn't

[@asheep7797]

@@IntergalacticPotato *destroys Chrome's servers and surprises Google with a new one* he is

[@hughstaffordlangan4949]

Damn, Bolt has an accurate watch.

[@GanerRL]

sports nerds disliking before watching the video

[@SKV4321]

Hi

[@TihadBaker]

Usain Bolt's wristwatch is intense...

[@RelatedGiraffe]

If only Bolt would have worn a watch that day, he would have noticed this outrageous fraud he was faced with! :D

[@ZeitrafferYEP]

basically,somebody moving is younger than somebody standing still.

[@Jason-ep3zb]

So we need to run as fast as we can to make we look young relative to other people

[@Entropy3ko]

Nope. It doesn't make you look young NOR physically younger. Simply Bolt will age less when he's running compared to when he's standing still. Look up the so-called twin paradox.

[@TorreFernand]

when he said "a little less", I thought he was going to talk about reaction times: between hearing the start pistol and him starting, and between him actually crossing the finish line and the stop boutton being pushed

[@Bella1899]

nein nein nein nein nein

[@Sasha1234575]

+panda Jein Jein Jein Jein Jein

[@justhuman988]

blah blah blah blah

[@007kuntasod]

BABABABABABABA

[@Dave-df5qv]

i see i have been beaten

[@kingsk0133]

Lol

[@kemp10]

1:50 Are American billions different than British billions?

[@LimbDee]

Yes

[@Sagezilla08]

@@LimbDee how so?

[@mateuszw.7905]

F.e. one american billion is equivalent to one polish milliard

[@Sagezilla08]

@@mateuszw.7905 Makes sense now. Thank you.

[@LNasterio]

I'm a physicist, and I find it funny how mathematicians are actually explaining the physics concept right...

[@aboubacaramine8689]

The guy is a physycist too

[@LNasterio]

Aboubacar Amine I see... that makes sense

[@TalooshDaBoss]

+Asterio What kind of physicist are you? Theoretical? Partial? Condensed Matter? Do you have a physics phd. I really want a theoretically physics phd when I get older. Also, what exactly are the jobs available for theorists. Mainly string theory and quantum field theory related. I've heard that most physicists don't get a physics related job. Do you have a physics related job? I saw this story on Reddit where someone graduated with a partial physics phd and then they worked as a bartender and are now applying for a calculus teaching job at a community college. I see no point in getting a physics degree if you are not going to contribute to physics. I've also heard that there are too many of old people in the field and young people find it hard to get a physics related job.

[@rohanackermann7912]

Physics is applied maths... why wouldn't he be explaining it correctly?

[@zbzb-ic1sr]

@TALOOSH If you find it hard to get a job in something physics-related, you might want to delve into the world of computation/programming and its application on physics-based simulations. The construction industry is in dire need of such. Believe me, a lot of design firms are looking for such people, esp. those with a firm grasp of thermodynamics and CFD.

[@tpfootballanalysis6752]

Usain Bolt didn't run exactly 9.6300000000000000000000

[@Tensho_C]

yea, must've been little more

[@tpfootballanalysis6752]

+IBA- ceo I think he ran closer to 9.640 than 9.630

[@tpfootballanalysis6752]

+Ingsoc officially at London 2012 he ran 9.64 maybe he got it wrong. I dunno

[@limoncenzo]

The point of the video is to show the impact of relativity. Usain Bolt is an example.

[@cortster12]

Not even the point. The point is teaching you about special relativity. The actual time he ran is irrelevant. The title was most likely a misguided attempt to attract sports fans, which obviously backfired as sports fans aren't the sharpest tools in the shed.

[@Rapter57]

I'm not even good at math and these videos continue to fascinate me.

[@glenn2687]

Declan Powers SAME

[@Lefers94]

+Alberto HasNothingToDo you need the exercise, because understanding the basics very well is key to understanding the complicated stuff.

[@Peter_1986]

+Alberto HasNothingToDo My lecturers usually recommend specific exercises that are different from each other, so that we don't spend too much time on a bunch of exercises that are about pretty much the exactly same thing.

[@mrronnylives]

people still use miles?

[@FeLiNe418]

+Aaron Baneseh Yes

[@NanoLT]

+Aaron Baneseh It takes a lot of money to change every single sign in the UK, and a lot of time and disruption.

[@reezechepniz7058]

+Aaron Baneseh I even heard of a whole country using miles... unbelievable, i know.

[@slyarsenal]

+Aaron Baneseh Only Americans because the so-called greatest nation on Earth still cant get with the times. They still use yards and feet FFS.

[@Gamerhero45]

+slyarsenal this dude right here typing out 4 paragraphs lol are you this much of a loser in real life? No one must talk to you I didn't read your bullcrap, I don't care what you said. tl;dr

[@1234Daan4321]

Quite remarkable to see the average IQ of the commenters drop when sports become involved

[@em-il1dq]

ouhhhhhhh shots fired

[@DPAE-xc4ph]

You think you're smarter than someone who plays sports?

[@edwardmurdoch5070]

I think he meant when someone is "commenting" about sports. It is a nice little joke, making fun of how our partiality in sports can get the best of us.

[@cfgcfh6350]

1234Daan4321 hahahahha

[@JanSanono]

That's sportitist

[@paris9332]

According to Bolt's theory of relativity, the actual number of people who would have watched this video is approximately 3037628 lesser if you take 'Usain Bolt' out of the caption.

[@swpanchakraborty3690]

Pari S

[@Inflation_Theory]

This is wrong. You should use general relativity theory to do the calculation. You should not just use the special relativity calculation since Bolt is not moving at a constant speed.

[@JamesKeithProduction]

Kid Goku did it in 8 seconds though.

[@jack71635]

Not a real person

[@anipetani2304]

+Jack 姜 goku is not real ?????????

[@jack71635]

+Đani Petani ......no. Grow up

[@sammiller5997]

+Jack 姜 it's a joke you idiot

[@jack71635]

+sam miller Someone who can't get a joke isn't an idiot

[@xiaolongye]

Great video, I have a limited understanding of this and you made it easy to grasp. Thanks!

[@aldoileanumeliber]

Really enjoyed this. Thank you!

[@chocolatechocochoco]

So... Did Usain Bolt REALLY run 100m in 9.63 seconds? Yes because the ones who measure it do not move.

[@ronaldderooij1774]

5+1 people missed the point entirely, and I therefore convict them to studying Einstein again!

[@IntegralMoon]

Ronald de Rooij Thank goodness someone picked up on this!

[@Bob-zx7io]

Wow, the amount of people who hate physics and math is really astounding. Do you people not understand that the video isn't trying to diminish what Bolt accomplished in any way? He's explaining the theory of relativity using an a event we can relate to.

[@kwonknow3869]

+Marvin Flugelmeister Just appreciate your ability to appreciate it. Not everyone who attends a soccer match is there to appreciate the nuances of the sport.

[@kierandocherty9475]

+kwon know football

[@DaVince21]

I'm not sure that it's the physics and the math that people hate, but the fact that it gets overshadowed by the example of Usain Bolt running being timed at an ever so slightly lower time. The actual content then goes unappreciated.

[@GOOCHIEZ]

Haters gonna hate.. They don't think, they don't consider, they don't take anything into account........they hate.

[@omikronweapon]

I don't think it has to do with being haters or not. haters hate because they 'like' it, but uneducated/lesser educated people might hate out of ignorance/unfamiliarity with the subject matter and get genuinely upset by a perceived 'attack'

[@zestyorangez]

how could he have ran 100m if he had to run 50m first? or 25m or 12.5m? it never stops

[@MlMZY630]

AHHH ZENO FOUND ME

[@TalSet333]

If that is a serious question, space can not get infinitely small

[@lancetschirhart7676]

Division by 2 isn't the right tool to use here. Use addition and subtraction.

[@roguec.9778]

you can solve this by using limits bro

[@theduplicity2164]

because the smaller the distance he has to run, the faster he runs it so e.g. he runs 100m in 10s, 50m in 5s, 25m in 2.5s and so forth so it doesn't matter if you can infinitely half the distance because you can infinitely double the speed to accommodate that. imo

[@HdBurningblade]

You forgot to factor in initial rounding of the record time, the speed of sound (from firing to reaching his ear), speed of light (time taken to electronically transmit signal to timer), and probably some other factors

[@Sorestlor]

Thats what i was thinking. If you want to be this accurate then sorry you have other factors to consider. Also the fact that none of the instruments are accurate enough to consider this stuff.

[@jimbo-fk4dq]

Do we have to factor in any possible PED use?

[@karac833]

Just a simple person here... But you suggest "time taken to electronically transmit signal to timer" is done at speed of light(SOL)... BUT ( I am probably wrong) but the signal would be at SOL only whilst conducted through a) superconductor, b) radio, light/laser, fibreoptic. While the electronic signal is within a copper/gold/silver conductor within the timer device(s), it's speed would be substantially slower than SOL. The only point I am suggesting SOL is achieved at certain conditions..... I do know I am being silly and petty... but also enjoying it all. Tell you something, I would love to see the theorist do the calculations...................................................

[@Sorestlor]

Signal in the electronics wont travel at the speed of light but even if it did you would still have to factor in that time. You could transfer signals faster than the speed of light using the spin of electrons theoretically since they respond well what seems to be instantly.

[@simil-kung5610]

That wasn't the point of the video.

[@Noxie_13]

yeah... why you not make something so off-topic ? so little timing is unmesurable ! Plus we count the finish when he cross the line, usually shoulders BUT the camera can't be precise enough because it takes the outfit and not the skin and it's not precise to the bilions of millimeter. So your theory's completely unaccurate. edit : if you want to talk about relativity, take better example, for instance the case of the 2 twins with one sent in space at high speed. All you do is nerding around trying to attract views by putting a highly searched name in the title.

[@humudu]

I have programming exam tomorrow, why am i filling my head with stuff like this now!!??

[@JOCOMANOable]

+humudu same here :D

[@kaanbostanc9032]

damn bro im.exactly studying for proggramming exam which 2 days later and my brain is boils in there and im here too

[@Silviu624]

+humudu lol, tomorrow i have a programmign exam too.... c++ POO exam.. and yet, i am here..

[@kaanbostanc9032]

Thank you :D And my friends this morning, thankfully i did really well in exam. i guess im gonna get an AA hehe :D and mine was MATLAB btw :D

[@humudu]

cool! I also did well :D

[@NathanY0ung]

I feel like majority of the viewers came here not because they were interesting in math but just out of controversy from the video title.

[@Gusburg]

I'm guessing all of the people who disliked the video have never studied maths or science and don't appreciate what this video is actually all about

[@kimghanson]

Amazing how often you guys make me laugh.

[@OLBastholm]

I watched just about 5 seconds of this. I didn't understand him at all.

[@savvaskastrinos8817]

+Xmus Jaxon Flaxon-Waxon III haha

[@MrKarlozz]

+Jack Barr-Baxter Yeah, its not that hard to understand... Though I would never had discovered it myself lol

[@jdub204]

+Jack Barr-Baxter you understand that's incredibly complicated. most people don't even understand variables.

[@gorber1971]

+OLBastholm Because he's a northerner.

[@MVBit]

It was actually 9.64 seconds, not 9.63.

[@xNathan2439x]

+Dante Thompson actually the world is fake and he never actually beat anything, the government just wants you to think he beat it... but he didn't you have been brainwashed and you must repent and repeal against your government and rise up and take control of your mind and DONT FALL UNDER THIS INDEFINITE RELIGIOUSLY UNINFORMED GOVERNMENT THAT WILL TRY TO PRESS THEIR RELIGOUS EVIL WAYS ONTO YOU ALL

[@DT-ov9sj]

+NATHAN BRANNON i think youre brain washing me

[@MilanTheAngel]

+tomforgot lollipops he already did

[@meekmillsdad8965]

+NATHAN BRANNON i dont think you get the joke. look it up

[@MilanTheAngel]

***** I do, this comment is very informative and interesting.

[@casaalebriol6298]

"Here we are at the olympic stadium in london"; proceeds drawing a straight line

[@piyushmajgawali1611]

Are you considering the time taken for the light reflected from Usain Bolt to reach the time keeper?

[@divypatel1002]

I was wondering the same thing.

[@ashtonkomodo]

I stopped it at 27 seconds I'm glad i did

[@lucacalderara9881]

Dude, what's your problem?

[@fabiansanhueza278]

Great video

[@DZIEWO0407]

2:19 NEIN NEIN NEIN NEIN NEIN NEIN

[@nofacee94]

The amount of people complaining on this video is too damn high! Stop taking it at face-value - he is explaining this funky relativity physics, the point of the video is not to say Usain was actually a bit slower.

[@strategen9124]

they probably still don't understand relativity at all and still have that high school impression towards physics

[@SkyFoxTale]

yea if we all had clocks that could measure to millionth nanoseconds

[@adreveiizorr9198]

That would be great! Just say what your time was and they be like da fuq!

[@mintoo2cool]

***** like your computer

[@nznegativeions]

bbababonbon..bonfire! nah

[@nznegativeions]

***** and everyone has one. oh, wait.

[@nznegativeions]

The Beaves Man Im rubbing one out right now

[@rayz-x]

the video has 3141592 views! which is pi

[@thegreenbeanfightingmachin5841]

Rayyan Sayeed you forgot the other infinite digits

[@rayz-x]

So... upon ignoring the other infinite digits, I made an error of 0.0000208044%

[@sarysa]

Kudos to KZbin if that's an easter egg threshold. Videos that get lots of daily views are usually approximated...funnily enough, 666 pops up often. (though I'm assuming they just floor their approximations, so it's not 667)

[@LeventK]

It's actually neither 3.141592 nor 3.1415926535897932384626433832795028841971693993751058208749445923078164... It's actually circumference divides by diameter 😎

[@goodpeopleoftheworldunite]

I don't see your point. . Lool

[@chtulurr]

It is sad that the actual point of this video is not coming across just because the example is about sports...

[@goodpeopleoftheworldunite]

Yeah it is, don't let your phobia of track and field cloud your calculations.

[@Treadstone7]

I calculated for myself before, that a car which is 5m in length and going at 28 m/s is about 65 femto-meters shorter than it usually is. I know what you're talking about and I absolutely see your point, but sometimes it's not good to be nerdy, even for nerds like us ;)

[@Adamslowsis]

So many idiots in the comments missing the point. The video creators know the 5 millionths of a nanosecond isnt significant to the race, they are simply having fun with the theory of relativity.

[@evanromes6754]

Just want to point out that he is actually not right about the time. This would only apply IF usains time was exactly 9.63000000000000... Which is probably not true

[@symeons1145]

Exact

[@ThejusMahajan]

Exactly! Trying to make a correction within the error bar makes no sense.

[@OhThatsHilarious]

haha W

[@Kosa647]

It doesn't change anything. The point was to show how relativity effects everyday life and that the reality is different then we see it. It is not a video about exact time of Usain Bolts 100m run.

[@minimon796]

The point is to learn general physics law, not how long actually Bolt ran

[@Madwolfx_]

5 years later yt suggested me this video 2021

[@XtenanetX]

If it was that little of a difference, who really gives a crap...

[@Guust_Flater]

Don't forget the time it takes for the soundwaves from the starting gun reaching the ears of the runners and the time before the brain reacts to the signal of the ears. That time totals up to 0,15 seconds 👍🏅

[@mumu135mumu554]

Did he just say that 299792458 probably wasn't the exact value? That's quite shameful.....

[@moritzt.110]

mumu135mumu554 was looking for this comment

[@darkbloom5385]

299,792,458 m/s ;)

[@D600Active]

Yep, since a metre is defined as the distance light travels in 1/299792458 seconds it is exact.

[@hrdyondrej]

Whole video I was thinking about the broken leg of athlete in 0:50.

[@adinitu]

ViXenTV LOL, my stomach literally hurts now.

[@AbuserTube]

ViXenTV His leg isn't broke, it just has two knees.

[@nicholasaurus]

Ondra Hrdy He's a mathematician not a doctor! It's not his job to worry about how many knees a person has.

[@hrdyondrej]

nicholasaurus So he can count pretty well, am I right?

[@luvmyhc]

Ondra Hrdy His leg isn't broke, it just has poliomyelitis

[@mariuszzo]

Wrong, Usain Bolt really runs -111111,22936763837 joule per dolar.

[@mariussefu3]

you forgot the time it takes for light to refract from bolt's body to the camera fotage

[@Atlas-gz9tk]

"some 'small' event called the Olimpics is going on in London" XD

[@MinecraftBuilder33]

So, Usain Bolt is Illuminati confirmed, or am I missing something?

[@beverleynovina890]

Your not missing anything

[@fisher00769]

I think most people have a difficulty with understanding this because they have the wrong concept of time. They think time doesn't change, that 1 second always means the 1 second we're used to, but that actually couldn't be further from the truth. When you move time slows down for you by a tiny factor, but when you move really fast, this change is actually significant. Our GPS systems would be completely useless if they didn't take this into account, they would be kilometres off your real position because the GPS satellites move very fast (~4km/s). These satellites calculate the position based on the time it takes for the signal to travel, so their clocks need to be adjusted to move faster than the usual to calculate properly.

[@fuckyougoogleplus8667]

Get over yourself. Most people who think about this at all don't have a hard time seeing this. I know you think you took a freshman physics course in college and therefore are some physics genius...but this is not advanced stuff.

[@fisher00769]

FuckYouGooglePlus Hey man, have you looked at the comments about how many people here are calling bullshit on it? I'm not physics genius lol I'm a med student, and this is definitely not advanced stuff, but if you look around here, you can see that people are having trouble with understanding it...

[@bbbf09]

Relativistic effects are very apparent for GPS - true. But in fact it is the general relativity effects due to gravity (difference between here on surface and out at orbit) that dominate over the speed effects (difference between ground and orbit speed). So much so that in fact the clocks run faster (not slower) on a satellite than an equivalent clock down here. The effect is similarly tiny though ... if you spent a whole of an average life time on the satellite your counterpart on earth would have aged abut only 1 second more than you. Small for us but large & significant effect for GPS measurements that must be taken into account. In orbit near extreme gravity fields the effects can be huge. This was used to realistic effect in the film interstellar which shows that if you ever find yourself close to a supermassive black hole then 1 hour spent there could indeed be equal to several years spent away from the gravity well.

[@LanceAtlas]

bbbf09 both special and general relativity effects (speed and gravity) have the potential to throw GPS off by large margins. Gravitational is greater, sure, but neither can be overlooked.

[@MrChkA]

This was awesome!!

[@esotericVideos]

Love the thumbnail artwork

[@snoopyguy21]

Couldn't it be said that he ran it in even less time because of when Usain Bolt ACTUALLY started running? You subtract Bolt's reaction time to the gun from the clock time and you would have a time from when he actually started moving towards the end of the track.

[@GTSRBOY]

This is assuming he ran it in 9.6300000000..according to the stadium clock, which he didn't

[@DrumCoversandytps]

All other calculations are based upon it. Meaning if we had a more precise time it wouldn't change the fact that according to Usain he actually ran a slightly shorter track in a shorter time period.

[@fuckyougoogleplus8667]

Sure he did. I don;t know why you would think otherwise. Absent any more degree of accuracy, that is EXACTLY what the stadium clock said. You can't start putting words in the stadium clock's mouth. Or numbers on its dial.

[@notacolt6879]

FuckYouGooglePlus The stadium clock only displaces so much numbers, we do not know the numbers after 9.63

[@fuckyougoogleplus8667]

Nota Colt And like I said...since there WAS no time keeping device with more degrees of accuracy, he did. Read the original post again..he said "according to the stadium clock." And yes..ACCORDING TO THE STADIUM CLOCK, he ran it in 9.63. It doesn't matter what any other clock would have said. According to the stadium clock, that was his time.

[@notacolt6879]

FuckYouGooglePlus Fine, but that amount of time that was subtracted doesn't make a difference anyways.. So why are we arguing about it?

[@flaviusclaudius7510]

I would have thought the finite speed of sound and reaction time telling him when to go, and the finite speed of light getting to the camera, would have had a significantly larger impact than time dilation from his speed. Not to mention the accuracy of the clock.

[@creativecarveciteclimb5684]

Yeah, the accuracy of the clock could differ by 0.004 seconds, and still round down/up to the same number.

[@sleeve9097]

NOT NOT NOT NOT

[@sccm100]

This takes being a nerd to a whole new level

[@Maxmekker42]

Lol

[@kian965]

+sebastian cuello I'm bursting with laughter.

[@SE45CX]

+sebastian cuello Yeah, I would avoid this guy for a conversation.

[@ianwubby6271]

+sebastian cuello Yeah, but it's great.

[@vaporainwaves]

So wait, if you move faster, time gets slower for you? Does it mean that astronauts in TKS will get older slower?

[@Morrvard]

Google "Twin Paradox" for the answer to your question :)

[@vaporainwaves]

Hmm, that means that if you would live near the equator, you would make bigger turns on the earth and get older slower, that's it, I am moving lol. Or should I become a jet pilot?

[@jasonsmith4114]

babusiaN1 You won't get older slower, you don't get it. First of all because the effects of relativity would be negligible at this speed, and because as I said there's no such thing as speed of time. What relavity says is that there's as many proper time as there's observant subjects so that there's no inertial frame that could be picked as a static reference, because everything's moving beside everything. In your very fast shuttle, you would get older exactly the same way that if you were on earth in YOUR perspective. I hope that the distinction I'm making here is clear (btw, I apologize for my terrible english...)

[@vaporainwaves]

I understand, but I want to see the future :D

[@jasonsmith4114]

babusiaN1 Well, in theory you can. Not your own one, but the one of all other people stayed on earth. But this is not a round trip, so maybe you should think to it twice... Anyway, from a practical point of view, maybe a shuttle like this isn't possible to enforce, but maybe it is, we don't know :)

[@leomoran142]

Actually, the number listed as the speed of light in metres per second *in a vacuum* IS exact... at 299,772,458. The length of a metre was redefined as the distance travelled by light in a vacuum in 1/299772458 of a second (which is defined as being the length of time that the caesium-133 atom takes to oscillate between two hyperfine states 9,192,631,770 times). The inaccuracy in the temporal differential calculation comes from the fact that light does not travel at the speed of light in vacuum when it is not in a vacuum.

[@vladtepes97]

he ran it in less than 9.63 seconds. 9.63 seconds represents the time from the sound of the starter's pistol to the runner crossing the finish line; this includes the time it takes for his central nervous system to react to the sound. if he was timed for only the time he actually ran it would be less than 9.63.

[@pepijnb4173]

if he was carrying a watch with a size to fit all those numbers. he would probably still been on his way

[@dixie_rekd9601]

so it was still 9.63 seconds..... when rounded... >.< watches / clock dont tend to measure time to the picosecond.... and if it did, the extra weight of him carrying a HUGE clock or a wristwatch 8 inches wide may have slowed him up a little.

[@saivarun5682]

AwesomeVindicator when u round 9.63 u get 9.6 or 10.00

[@planetwalker]

Sai Varun or 9.65 or even 9.5 pending on the criteria.

[@MrGOLDENCUPCAKE1]

AwesomeVindicator They're talking in figurative terms not literal....

[@chsxtian]

AwesomeVindicator You missed the point by a lightyear.

[@strike667]

AwesomeVindicator that's not the point of this video...

[@tenienteramires4428]

For people from the US, 100 m are roughly 110 yd or 330 ft

[@ayershov777]

so if the track gets shorter, and then longer, is its mass still the same the whole time? or does mass get destroyed, and then recreated?

[@CleverGoatee]

lel

[@4Y0P]

Tl;dr = yeah he did, but not really

[@xNinj4xHD]

+Whims this answered none of my questions

[@ondrejveres435]

why do so many people trashtalk this video? its meant to be just fun fact not a criticism to the olympics ffs...

[@arttuhintsala9717]

Well it is because of the slight clickbait implying that there is a major difference somewhere that no1 noticed. And as this is a math channel it would be expected that they wouldn't use clickbait. Happy?

[@Martin-ki8jv]

pears i eat Since it's a math channel you could also expect the difference to be very small.

[@arttuhintsala9717]

Roadman Shaq there is really nothing wrong with the video. Its just the fact that so many of the views coming from outside the channel (about 50%). They expect it being something major as they do not know the channel and then it is just a worthless fact.

[@arttuhintsala9717]

Also related to the 9.63s there is an inaccuracy in the stadium clock that is so much bigger than the difference this guy found that it makes his fact even more worthless

[@Martin-ki8jv]

pears i eat Well it's still not clickbait. It's not their problem people would think it's a big difference. But I see your point.

[@erik8467]

Yes he did, end of story there I just saved u 6minutes

[@smashgod6489]

It's 7

[@TUNDRA2529]

It's 6 when you take into account special relativity.

[@rousingnizam]

Thanx a lot 😂

[@owlflame]

I genuinely hope to never find you on another numberfile video if you're gonna be ignorant about it.

[@maxekstrom6153]

Now we have to talk about the accuracy of the clocks. I think it matters more in this case

[@SuperMaDBrothers]

I saw everything in this video coming lol

[@San_D._Beard]

i always do my math with a sharpie on a brown paper bag

[@dan445678]

Actually, at 5:24 when he says "that's probably not exact either" referring to the speed of light, he's wrong. 299792458m/s is the exact speed of light because we now define the meter around the speed of light, so it fits perfectly to it mathematically

[@pauloguga]

an add with usain bolt popped up right before this video lol

[@ncky2431]

What about his reaction time?

[@yo-lab]

Here is a non biologic-zone sry

[@tachyon6376]

+Niky Kaminsky MR DARBY

[@ncky2431]

+Yo-Lab k

[@TheIcecreamtaco]

+Yo-Lab where is here? *brain explodes*

[@turboblitz6958]

He's so happy about him self I love it lol

[@someoneonearth2619]

im just replying you after 4 years just to tell you that your comment is been read ny someone :)

[@agradman]

You're a tremendously talented educator, but this video is a real standout!!!

[@musliksolihin8960]

bolt is now living in a seperate space and time from us

[@Gaming4Justice]

2:17 NEIN NEIN NEIN NEIN!

[@tommycp29]

so? you believe the stadium clock @ thats much decimal place accuracy? if not i negative to this video.

[@aniketaggarwal1224]

The stadium clock is not so accurate to tell time upto pico seconds so foolish to say it was 9.63 actually and 9.6299 ..95 actually

[@Trinexx42]

Actually, 299792458 m/s is *exactly* the speed of light. The length of the meter is defined as the distance light travels in 1/299792458 seconds, and consequently light *must* travel 299792458 meters per second.

[@armandmodjabi8382]

So wrong.

[@TruthNerds]

@@armandmodjabi8382 Indeed you are.

[@armandmodjabi8382]

@@TruthNerds haha

[@mjSnap]

You could only say he didn't run the full course if he had stopped precisely at the 100m mark. Runners obviously run past the finish line, so he made up for the tiny discrepancy.

[@bob123789456]

these are the types of Numberphile videos that piss me off

[@thebosspenguin1194]

LOL they delete these comments

[@sebastiand152]

The watch is on his arm, which moves back and forward during the run. How does this impact the result? And could you come up with a more precise model?

[@mb789-i1g]

Nein! Nein! Nein! Nein! 2:20

[@beckyyoung6445]

Did you guys ever think that the stadium clock is rounded up?

[@ardenvarley-twyman8352]

What's your point?

[@jaysaspara7623]

+Arden Varley-Twyman he meant that the nein nein nein nein nein was rounded off to 9.63

[@ahadyeh15]

lol, you clearly don't understand the video or what special relativity is. If we had the exact value of the clock in the stadium accurate to the 20 digits or so that was in the video, the times still would have differed by the same amount. period.

[@sonudilli2450]

Yes there are inaccuracies acclimated with that, and many other factors. but what this video is trying to say -as mentioned by fellow viewer, that even if everything was accurate relativity will have a different time

[@sonudilli2450]

*associated

[@dieudonneouedraogo7206]

So instead of 9.63 he ran 9.63? I knew they were trolling us

[@maya_mochi]

This is so intriguing

[@pedrocaminha3834]

The same people who says that Eistein theory is fantastic without really knowing what einsten said, are the people who dislike this video, just thinking that the numberphille wants to minize Usain bolt achievment. Numberphile just want to show us the relativite theory with usain bolt as a example.

[@Mistrinho]

Isn't this that kind of thing where, if you had a very fast plane and a atomic clock, and you went around the Earth with that plane, less time would progress in your plane than on Earth?

[@kevinblank1481]

yes

[@yenice3652]

so when you land would it be the future compared to if you sat here on earth the whole time

[@DaVince21]

Heh, if he had used that example to explain the exact same concept this video would not have received all the undeserved dislikes.

[@luxnox9303]

That thing is called the theory of relativity FYI

[@Martin-ki8jv]

Smoove no.