Would Headlights Work at Light Speed?

  • Published on Feb 25, 2015
  • If you were driving at the speed of light and turned on your headlights, what would happen?
    Twitter: twitter.com/tweetsauce
    Instagram: instagram.com/electricpants
    Sources and extras below!!
    Thanks to Jude for asking me this question on twitter! twitter.com/stefanikj5/status/550865272895447041
    “The Life of the Cosmos” by Lee Smolin: www.amazon.co.uk/The-Life-Cosmos-Lee-Smolin/dp/0195126645
    “In Search of the Multiverse” by John Gribbin: www.amazon.co.uk/In-Search-Multiverse-John-Gribbin/dp/0141036117
    “The Pig That Wants to be Eaten: by Julian Baggini: www.amazon.co.uk/The-Pig-That-Wants-Eaten/dp/1847081282
    Relevant MinutePhysics videos:
    light slowing down in glass: thexvid.com/video/FAivtXJOsiI/video.html
    a different perspective from Sixty Symbols about light slowing down: thexvid.com/video/CiHN0ZWE5bk/video.html
    Why is “c” the speed of light?
    Car at light speed:
    Light speed is the same in all inertial frames of reference:
    Relativistic addition of velocities:
    doppler shift:
    Light speed and catching-up to light.
    Other good relativity resources: newt.phys.unsw.edu.au/einsteinlight/
    Light echo footage: www.spacetelescope.org/videos/heic0617a/
    “fine-tuned” universe:
    Irrational numbers: mathworld.wolfram.com/IrrationalNumber.html
    a million digits of pi: www.piday.org/million/
    Vsauce2: thexvid.com/user/Vsauce2
    Vsauce3: thexvid.com/user/Vsauce3
    animated drawings by Guy Larsen twitter.com/guylar
    rocketship animation by Eric Langay twitter.com/ericlanglay
  • Science & TechnologyScience & Technology

Comments • 21 155

  • KanedaSyndrome
    KanedaSyndrome 3 hours ago

    My theory: We exist as part of a probability space of functions. Our existence is inevitable and static as part of the math that can be used to describe our universe and us. Everything that can be mathematically described is as real as us. And yes, that probably means that Harry Potter and everything that happened in the books/movies is real in their own universe. This also lays out why we even exist to begin with, because we have to, because we can be described mathematically.

  • KanedaSyndrome
    KanedaSyndrome 3 hours ago

    You can program pi. You enter it as a formula that keeps iterating the further the creations prod it.

  • Joe Q
    Joe Q 9 hours ago

    So you're basically saying if I stop getting dressed at the speed of light my wife will appear to get dressed faster? 😉

  • Screen changer
    Screen changer 22 hours ago

    My earth has 69586687884785478411124589007538574663823563 suns

  • Heidi Harlis
    Heidi Harlis Day ago

    If you cut make A car whith no mas u Will still have mass

  • Samyak Maurya
    Samyak Maurya Day ago +1

    What's that song starting at 1:55? It plays for a couple of minutes in the background.

  • cone man
    cone man 3 days ago

    Michael has found a fridge that can see.

    *bois we are in a simulation afterall*

  • Thomas Neal
    Thomas Neal 3 days ago

    the idea that a simulation would be easier to create than a spontaneous universe assumes that a spontaneous universe is hard to create.
    this, is an unwarranted assumption given the timescales we already have observed in this universe.
    ergo, the simulation hypothesis is actually based on much poorer assumptions than the standard physics model, and should be rejected simply for that reason.

  • dhruva mehrotra
    dhruva mehrotra 3 days ago

    What the heck is a SUN??

  • Kushagra Raj
    Kushagra Raj 3 days ago +1

    What do you mean 'but' its supposed to be that way, isn't it?

  • Volmax Dnb
    Volmax Dnb 4 days ago

    02:49 when i ask a German girl if she wants to have sex with me

  • GodDemis
    GodDemis 4 days ago

    first minute is filler, total waste of time.

  • Shikhir a
    Shikhir a 4 days ago

    Wait what!!!! Wouldn't we travel 299792458m in one second? Time will pass but at a very very very very very slow rate compared to a stationary object

  • MR.Stkrdknmiballs
    MR.Stkrdknmiballs 4 days ago

    But nutrinos have mass and go the speed of light

  • LuckyTheDiamond
    LuckyTheDiamond 5 days ago +1

    So, let's assume we can break the laws of physics a little bit (Objects with mass would be able to travel the speed of light, and massless objects could travel slower), if you instantly started travelling at c, and then stopped, would it feel like you just instantly teleported in no time at all? Would you just experience nothing forever and be dead? Would you end up at the end of time and space?

  • Marek Pająk
    Marek Pająk 5 days ago

    Interesting question. When a plane fires a rocket the total speed of the rocket is higher because plane velocity + rocket velocity = total rocket velocity. But physics teaches that speed of light is the absolute limit in our universe. But there may be another universe where laws of physics are different.

  • X D
    X D 6 days ago

    yo if an object that emits light would travel at lightspeed would that light travel *FASTER* than the speed of light?

  • Zambicus
    Zambicus 6 days ago

    I don't get it, why COULDN'T a simulation contain irrational numbers? Why do they need to put the whole sequence of digits in when they can just describe it as "the square root of two" or "circumference to diameter ratio of a circle"?

  • Tim Mah
    Tim Mah 7 days ago

    To travel at the speed of light all your mass would be converted to energy aka photons lol so nothing would retain its physical form.

  • Royal Pro YT
    Royal Pro YT 7 days ago

    No matter what in you are, if you travel at the light speed you can' t see anything because any light can' t reach your eyes.

  • Joshua HIckerson
    Joshua HIckerson 9 days ago

    Notice how people say universe, thats cool and all but, what about a multiverse? meaning many universes combined. But, not combined like when you add a liter of water to a bottle of water, no no no instead combined like there are differenct sections of them at the same spot and the same time. Things like that could possibly explain why things are so far apart. or maybe a universe is a multiverse but just smaller. Heh who knows maybe someone will find out in the future but, for now we just have to wait.

  • Farookh Matawi
    Farookh Matawi 9 days ago

    we alll know we have ten suns, dont be joking, micheal

  • Robert Lavigne
    Robert Lavigne 9 days ago

    A universe full of color and scientist stare in to the black hole and wonder: "whom?".

  • Flameshaper_
    Flameshaper_ 9 days ago

    Brain hurt help

  • Saturated Fat
    Saturated Fat 9 days ago

    Maybe reality doesnt exist and is what we perceive to be real so a simulation could be considered a reality.

  • John King'ori
    John King'ori 10 days ago

    What kind of channel is this with a quack who thinks the Earth has one sun? Who knows? Maybe he's also a round Earth nut job.

  • Doomxeen
    Doomxeen 10 days ago

    This is still the best Vsauce video!

  • lupsaman
    lupsaman 10 days ago

    it is a simulation and we are real. infinity, undefined energy defines itself to create experience.

  • Tom Cox
    Tom Cox 10 days ago

    Assuming that quarks have a point in space that they are said to occupy, like we are saying of photons, PERHAPS due to their speed and how it relates to the force that makes them orbit(Fingers crossed on this being how they work) determines the size of their resulting protons/neutrons, is what determined the size of atoms, and also their density, affecting not only the distribution of particles throughout the universe and the relative distance/speed necessary for a planet to orbit a star, but also the size of molecules, and resulting organisms. If the "speed" of quarks was determined to be a certain proportion to the speed of light, then this could determine our understanding of distance, and so the distance light travels. (and similarly, the proportional speed that we orbit the sun which could be traced to how we label 1 second to be as long as it is. Though organisms didn't need to develop time, so that's less related). Cool thought, thanks for the video!

  • Debabrata Dey
    Debabrata Dey 11 days ago

    Simulation ? We call that project Alicization

  • Schneider Mariane
    Schneider Mariane 11 days ago

    Which headlights At the speed of light, there are no headlights. You are a spotlight!

  • Greggory
    Greggory 11 days ago

    Cool, I managed to think of what he said here before watching.

  • Mr. Blue
    Mr. Blue 11 days ago

    I liked this. My answer is no headlight no light. And I am not sure I liked, that we were shit out of a black hole. But I guess what go in must come out. Well I not the one due to do not like height . lol! Thanks! I learned something.

  • David Swift
    David Swift 12 days ago

    Where might the creators of the simulation(s) originate from?

  • Vaillancourt Martin
    Vaillancourt Martin 13 days ago


  • RANDOM æð
    RANDOM æð 13 days ago +1

    I take it, you've done this? Damn that's really awesome.

  • The Ancient Destroyer Of Worlds

    I’m really confused, you have only one sun?

  • Fred
    Fred 13 days ago

    If pi truly is never ending, at some point it will repeat. In fact if it is never ending, it will repeat many times.

  • Raik
    Raik 14 days ago

    But what if the programmer knew we well feel reassured that we're not in a simulation thanks to the irrational numbers...or maybe programmed that himself.

  • Angelo The Youtuber
    Angelo The Youtuber 14 days ago +1

    I only wanted to know if headlights work at light speed...

    ... but NO! We NEED to know we probably live in a simulation.

  • Ricardo Alvarado
    Ricardo Alvarado 14 days ago

    1:43 I don’t believe this is correct. Diffraction does not work this way

  • Arjun Anand
    Arjun Anand 14 days ago

    So moving at the speed of light is time travel.

    • Fred
      Fred 13 days ago

      only forward. the same direction that we are going now, only faster.

  • rauldoty
    rauldoty 15 days ago

    What if the universe simulation was procedurally generated? Then it it could fit all irrational numbers quite easily.

  • Tada_WAV
    Tada_WAV 15 days ago

    What if it were built into the simulation to generate irrational numbers on the fly with say 10 billion digits and once civilisations in the simulation develop computers and are advanced enough to calculate them, just
    generate more digits endlessly like a cat and mouse game with the real people always 10 digits ahead of the ones in the simulation. That would give the illusion of having irrational numbers by just making sure you generate more digits than the inhabitants of the simulation can calculate.

  • Sazy Plew
    Sazy Plew 15 days ago

    Time is a constructed illusion...in that case any equation that’ll account for a theory of everything has to NOT include time or at least time as we “know” it! Actually, throw time out and start over, sans time, for everything. So when is that train leaving and how will that second faster train arrive!?!

  • KiranProGamer
    KiranProGamer 16 days ago

    But why??

  • Mylok
    Mylok 16 days ago


  • Achyuth Thouta
    Achyuth Thouta 16 days ago

    I still dont understand that spaceships thing you said. Don't judge me .

  • Lubka Sintajová
    Lubka Sintajová 16 days ago

    A infinite universe Theory is not really possible because there will be infinite travellers who can destroy infinite universes by doing anything and as we can see that we are not destroyed there is a chance 1 in infiniti that our dimension can't be destroyed

  • Manish Kishorpuria
    Manish Kishorpuria 17 days ago

    Hmm... Begs the question, what's time?

  • kuma982
    kuma982 17 days ago +1

    @ 3:30 why would the light shift to blue and red, if i dont moving?

  • Neel Srivastava
    Neel Srivastava 17 days ago

    Well... lets try keeping all the quantum physics, wave nature, particle nature aside... Let us try to compare the question to the small scale scenario when we throw an object from a moving platform (in space vacuum ofc neglecting the space friction), results would be somewhat 2x the speed of light. Maybe its not but who knows :D

    MMONNEERR IS_A_GUY 18 days ago

    So no?

  • Paws ForHead
    Paws ForHead 18 days ago

    Why is the title and description of this video being translated into my languag(norwegian)? Is it like this for everyone? (english speakers would obviously not notice)

  • Ayava Kyavata
    Ayava Kyavata 18 days ago

    So does π prove that there is a reality outside and "above" this one? That as close as our simulation comes to expressing reality, Plato's "outside the cave," that there are some things unable to be perfectly expressed?

  • Mocha
    Mocha 18 days ago

    Where I'd the config file for the laws of physics

  • Mocha
    Mocha 18 days ago +1

    I'm a photon.
    I like to say oof so loud that everyone hears me
    So when u turn on the lights u hear oof

  • Only slightly insane
    Only slightly insane 18 days ago

    I find it hilarious the at 9:17 Michael addressed a human from another universe

  • Harvey Harbicht
    Harvey Harbicht 19 days ago

    If you aim a laser into space and assume infinite power would the beam eventually form a corkscrew shape due to the far end still traveling but the source revolving and moving in orbit with the earth?
    If you can see a nuclear blast aren't you already radiated? I assume all of it travels at the same speed. Gamma rays, xrays and light.
    Why does a red or green laser shimmer? Is it because the light is too pure and we don't have enough cones for full resolution of that pure a color?
    Why are lasers only red or green? Why no blue?

  • joseph jackson
    joseph jackson 19 days ago +2

    _just like the simulations_

  • Luan Silva
    Luan Silva 20 days ago

    e se usar esse conceito de ''achatamento'' relacionada a velocidade para descrever e visualizar espectro de ondas de cada elemento ... já que tais photons estão todos se movendo a C .... talvez seja possível que cada elemento emita um ''pacote de quanta que poderia ser observado em 3D'' uma espécie de receita encriptada em um ''codigo de barras''

  • Andrew Rueda
    Andrew Rueda 21 day ago


  • WaveYT4
    WaveYT4 22 days ago

    Who else watches vsauce without never knowing what the heck he is talking about? Lol

  • Daniel Vélez
    Daniel Vélez 22 days ago

    Woah... I just wanted to see if headlights work at light speed. Now im questioning my existence.

  • divljacina1
    divljacina1 22 days ago

    its kind a confusing....how something can have mass in space....

  • itisimatadvc
    itisimatadvc 22 days ago

    When it comes to cool stuff, you can't hold a candle to photons.

  • AL Can
    AL Can 22 days ago

    So experiments using light, such as the double slit experiment, the light or proton as soon as it is shoot out of the device (device producing the proton or electron) it travels every path possible in every direction possible even before being detected?
    Since light is a universal speed limit we cannot create sensors that can adequately detect light, when TIME is part of the experiment. Or TIME is unknowingly part of an experiment.

  • Emanuel Pereira
    Emanuel Pereira 23 days ago

    Not watched it yet... But let's see. Car traveling a the speed of light does not nullify the lamps ability to create light. And though I don't think we'd see light projection (because the car would be moving at the same speed)... We'd see the lamp light up...

  • Goratchthemule
    Goratchthemule 23 days ago

    If one speed of light left earth to the east and one in the west. they would in theory be moving the speed of light x2 away from each other. But they say they're not.

  • Mike Warski
    Mike Warski 23 days ago

    But what would happen to the light from the headlight if it was possible

  • AR-Sith F.Austin
    AR-Sith F.Austin 24 days ago

    Intelligent design.... Perfection in motion.

  • Craig Usselman
    Craig Usselman 24 days ago

    why are black holes so greedy eating time and and light are they emotionally eating...

  • Stefan Duginski
    Stefan Duginski 24 days ago

    whoa wait. If we use particle accelerators to slow down time for those particles so we can observe their usually microsecond-long decays over the course of seconds, what if photons decay over time? But time does not pass at the speed of light, so they never decay?

  • Marianna M
    Marianna M 25 days ago

    light doesn't exist

  • New York Drive
    New York Drive 25 days ago

    Didn’t really answer my question but okay

  • Hey Guys, This Is My New Name

    What would happen if you turned your head lights on while going at the speed of light?
    It's simple, irrational numbers prove we're not in a simulation.

  • N 0178
    N 0178 25 days ago

    So the one thing that disproves the simulation theory, is pi. Thats just funny af

  • flerper derper
    flerper derper 26 days ago

    would a car drive if it was driving

  • true fire
    true fire 26 days ago

    Didn’t someone already build a camera that can take pictures at the speed of light ?

  • 1,000 subs with no videos

    There are 10 to the 86th power (that's 1 with 86 zeros after it) elementary particles in the universe. If whoever programmed this theoretical simulation of a universe could program all of those, I'm sure programming 2.7 trillion (the number of digits of pi we currently know) digits wouldn't be that much of a struggle to them.

  • Leon Bittis
    Leon Bittis 27 days ago

    So, we've learned that time stops when you're moving at light speed. But what if you're travelling faster than light? Would the time go backwards then?

  • carter swanson
    carter swanson 27 days ago

    Love what u did with the 2 suns multiverse

  • DrunN
    DrunN 27 days ago

    In mY UniVErSe EaRtH iS FlaT. WhAT ABoUT yOuRs?

  • goovind narula
    goovind narula 27 days ago

    what if the supernatural beings that control our simulations just keep adding digits of pie as they find it. so what if they havent found it, we could still be in a simulation. they probably sent in the author who wrote the pig book as a simulation too to dismiss our ideas of it

  • Benjamin Jones
    Benjamin Jones 28 days ago +1

    Why'd you make the video then ?

  • Preston Poling
    Preston Poling 28 days ago

    Here's a question I've always wanted explained...you might be just the guy to do it.... imagine for a moment that a hole could be dug from one side of the earth, through the core all the way to the other side. Now imagine that someone jumped into that hole (disregard the fact that this jumper would be incinerated)....logic would say that the person keep falling until they came out the other end of the hole, but obviously at some point it would no longer be "falling" down a hole but they would be rising out of the other end... so my question is what would actually happen? Would they make it to the center and experience zero gravity? Would the rate of decent push them out the other end? This has boggled my mind for years. There has to be a way to figure this out.

    • Arthur TV
      Arthur TV 26 days ago

      Assuming the hole protected you from the immense heat of the core of the earth, and the air pressure remained constant throughout the hole, we can apply physical laws to figure out what would happen.
      When you first jump in, you would fall towards the majority of earth's matter due to gravity. You would fall down at terminal velocity until you reached the centre. At this point, gravity would be pulling you (essentially) equally in all directions. Your velocity would mean that you continue past this point, but you would not reach the other side as the air resistance would slow you down. You would eventually slow down, and then fall back towards the centre, before passing it again, and stopping a little closer to the centre with each fall. Eventually, you would slow down and come to a complete stand-still, floating perfectly in what would feel like zero gravity, just as you first suggested.
      Without air resistance (say, in a perfect vacuum wearing a space suit), you would fall through the earth, past the centre, slowing down more and more as you reached the surface, until you stop perfectly on the other side, and fell back towards the centre again. This would continue forever, and this is known as 'simple harmonic motion', as you further suggested.
      Hope this helps!

  • Dylan
    Dylan 28 days ago

    Just wow
    They are Videos you watch am After it finished you are just like WOW that was mind blowing
    Thank you
    (From Germany )

  • Paul Kiraly
    Paul Kiraly 28 days ago

    1:15 haha I C what u did there

  • Simon Guerra
    Simon Guerra 28 days ago

    Anyone watching from 7 Sun Earth?

  • Jacob Turnbaugh
    Jacob Turnbaugh 28 days ago

    The video was all good until you had to bring up simulation theory. Why is it that a theory based on Human technology has become a popular proponent of our actual reality? It's because, it's bullshit. Existence should not require existence to exist. It makes no sense and it is just Flat earth only harder to actually debunk.

    JOSIF STALIN 29 days ago


  • NegoNam
    NegoNam 29 days ago

    what's the music at 1:55 ?

  • 167IsaBella
    167IsaBella 29 days ago

    If I see the title of this video in my native language (and not english), does it mean, that the cookies are kicked in?

  • Col.Glover 413
    Col.Glover 413 29 days ago

    Go watch Kent Hovind ✝️

  • SteppupFoRetsam
    SteppupFoRetsam 29 days ago

    We live in a simulated society

  • Guitar Wala
    Guitar Wala 29 days ago

    Who's is vsauce when he says hey vsauce?

  • Devon Couch
    Devon Couch 29 days ago

    As far as PI being never ending as an arguement for how this is a simulation i will suggest you play Grand Theft Auto 4, you can go on forever and the water never ends. You never reach the end because it is the same thing copied and pasted outward infinetly.
    "Like if i copy and paste this"
    Like if i copy and paste this
    "Like if i copy and paste this
    Like if i copy and paste this"

    "Like if i copy and paste this"
    Like if i copy and paste this
    "Like if i copy and paste this
    Like if i copy and paste this"
    The more i keep going the more amount of text i can produce with the same amount of labor (one click) not saying im right and this is simulation, just point out things can be seemingly infinite. What if you realise PI eventually repeats itself after a few quadrillion numbers? Where would it even be written for you to go check all of PI? Gigantic book or never ending website? Could it not just be auto generated? Like do a math problem on a calulator that gives you PI as the answer or does that break physics?

  • super knight
    super knight 29 days ago +1

    Wait are some videos on TheXvid from other universe

  • Devon Couch
    Devon Couch 29 days ago

    I just started i thinking if i put my hand in front of my other hand is the hand behind my hand actually there? I cant see its light yet so is it in this dimension?

  • Devon Couch
    Devon Couch 29 days ago

    Most the time you make sense but this just blew my fucking mind i cant even comprehend it. Do they calculate all this in video games?

    • Devon Couch
      Devon Couch 29 days ago

      I thought i didnt understand cause i was high and its 2 AM but i just realised its cause you didnt use the vsauce music. No new music man