Parallel Worlds Probably Exist. Here’s Why

6 mar 2020
7 406 803 Áhorf

The most elegant interpretation of quantum mechanics is the universe is constantly splitting
A portion of this video was sponsored by Norton. Get up to 60% off the first year (annually billed) here: or use promo code VERITASIUM
Special thanks to:
Prof. Sean Carroll
His book, a major source for this video is 'Something Deeply Hidden: Quantum Worlds and The Emergence of Spacetime'
Code for solving the Schrödinger equation by Jonny Hyman available here:
I learned quantum mechanics the traditional 'Copenhagen Interpretation' way. We can use the Schrödinger equation to solve for and evolve wave functions. Then we invoke wave-particle duality, in essence things we detect as particles can behave as waves when they aren't interacting with anything. But when there is a measurement, the wave function collapses leaving us with a definite particle detection. If we repeat the experiment many times, we find the statistics of these results mirror the amplitude of the wave function squared. Hence the Born rule came into being, saying the wave function should be interpreted statistically, that our universe at the most fundamental scale is probabilistic rather than deterministic. This did not sit well with scientists like Einstein and Schrödinger who believed there must be more going on, perhaps 'hidden variables'.
In the 1950's Hugh Everett proposed the Many Worlds interpretation of quantum mechanics. It is so logical in hindsight but with a bias towards the classical world, experiments and measurements to guide their thinking, it's understandable why the founders of quantum theory didn't come up with it. Rather than proposing different dynamics for measurement, Everett suggests that measurement is something that happens naturally in the course of quantum particles interacting with each other. The conclusion is inescapable. There is nothing special about measurement, it is just the observer becoming entangled with a wave function in a superposition. Since one observer can experience only their own branch, it appears as if the other possibilities have disappeared but in reality there is no reason why they could not still exist and just fail to interact with the other branches. This is caused by environmental decoherence.
Schrodinger's cat animation by Iván Tello
Wave functions, double slit and entanglement animation by Jonny Hyman
Filming of opening sequence by Casey Rentz
Special thanks to Mithuna Y, Raquel Nuno and Dianna Cowern for feedback on the script
Music from "Experimental 1" "Serene Story 2" "Seaweed" "Colorful Animation 4"

  • Simple summary of the video Because it’s a theory and we can’t really prove it so deal with it

    TLB CanineTLB Canine6 mínútum síðan
  • So if we go back to the start of time, then there are universes without us at ALL. Hmm!

    Gary BlakeGary Blake18 mínútum síðan
  • hi

    Io OkIo Ok3 klukkustundum síðan
  • Billion ppl with gazillion super impositions and infinite outcomes

    Sai ChanderSai Chander4 klukkustundum síðan
  • so your telling me that there is actually a version of me that understood that whole vidio

    Kai YtKai Yt8 klukkustundum síðan
  • That means there’s a universe that I can understand the first 10 minutes of this video

    Aron BalemeAron Baleme14 klukkustundum síðan
  • What happens if we do not open the box

    Mohit DethaMohit Detha14 klukkustundum síðan
  • i love how im so bad at physics but this is so fun

    Andrei GAndrei G15 klukkustundum síðan
  • Parallel worlds "solves" a conundrum by presenting an infinitely more complicated conundrum as the "solution". I don't buy it. I'll stick with conservation of matter and energy, thank you.

    andyiswonderfulandyiswonderful16 klukkustundum síðan
  • The mere chronometer presumably heap because flood neurochemically count modulo a square flugelhorn. ill, abiding wrecker

    Zhu KevinZhu Kevin16 klukkustundum síðan
  • ?If the universe isn't infinite... there must be an end..... if it ends, what is on the other side of the wall?

    Rock FanRock FanDegi Síðan síðan
  • This solves pretty much all paradoxes with time travel

    PoképroPoképroDegi Síðan síðan
  • Are you saying everything in the universe could be described by one equation?

    Michael LouthanMichael LouthanDegi Síðan síðan
  • It seemed to me like flip creating each part different..n each part could become something else ( that's another world) though what we see later on in that flip book is the reality.... This is really cool though..💜

    Prakhar RaviPrakhar RaviDegi Síðan síðan
  • i don't understand a thing but i watch anyway

    Jamaico ConcepcionJamaico ConcepcionDegi Síðan síðan
  • Plot twist: this earth is the parrarel world

    Azyrca SenpaiAzyrca SenpaiDegi Síðan síðan
  • so that's how the story of Dark was born !

    Akanksha SinhaAkanksha SinhaDegi Síðan síðan
  • This is why i know evolution is true. After watching and failing to understand this video i have decided I feel more related to a chimp than to Derek.

    PaulPaulDegi Síðan síðan
  • at 10:41 am I the only one who got rick and morty vibes

    Zoe CottonZoe CottonDegi Síðan síðan
  • How do we know that the two outcomes can never interact?

    Peter MacDonaldPeter MacDonaldDegi Síðan síðan
  • Which universe do I have money in?

    shawneagles81shawneagles81Degi Síðan síðan
  • Botschaft Bots werden realisiert

    Maren StrohkarkMaren StrohkarkDegi Síðan síðan
  • I just love this so much. This is the conversation I've had with myself or the occasional copenhagenist. Do I have to become a full blown physicist to hang out and talk interactively to geniuses like you guys? Hmmm what can I offer in return that you don't already have or know? Well cheers thanks for making and sharing this, you guys seem super cool! Cheers

    Tommy SullivanTommy SullivanDegi Síðan síðan
  • who came here after dark netflix season 3?

    riggeddiriggeddiDegi Síðan síðan
  • why is the branching limited to 2 splits? what if each split reality sees itself and a different branch from your own perspective? For example, for us, the cat may either be dead or alive, but for the other branch, the cat is either alive, or not even there (perhaps someone secretly removed the cat when you as the observer was not looking). Maybe not the best example, but there are many situations that can have more than 2 outcomes, so if there is any splitting, i would imagine that there are far more than we could calculate from the limited perspective of our reality.

    hobbeshobbes2 dögum síðan
  • The scientist remind me of Chris Hansen

    Jordan SJordan S2 dögum síðan
  • Philosophical thought experiment: Let's say we invent a basic quantum coinflipping device with a perfect 50/50 distribution. Then we gather a few thousand participants that each pay an entry fee of a 1000$ to participate in the grand head-or-tails knockout tournament where the winner takes it all. According to the many-worlds theory, everyone ends up a winner and becomes a millionaire in one of the resulting, equally likely, parallel universes. Of course, when this event is viewed in the rear mirror, a losing participant can't claim that parallel worlds are disproven, since every parallel universe will have N-1 losers, but from the outset you would "know" that you're going to win in a universe that's exactly as valid and likely as all the others. So, you'd be an idiot not to participate... right?

    Uffe Poul HansenUffe Poul Hansen2 dögum síðan
  • I am still wondering why ISpast show me 20:00

    Prince BujethiaPrince Bujethia2 dögum síðan
  • I like your funny words magic man

    BrizzyBrizzy2 dögum síðan
  • Donnie Darko 😂

    Jack TorranceJack Torrance2 dögum síðan

    Nabhanyu JoshiNabhanyu Joshi2 dögum síðan
  • How can cat be dead or alive before measurement if I can hear it licking and meowing. This analogy is not perfect. Find a better one for better comprehension.

    HuntingCapricciosHuntingCapriccios2 dögum síðan
  • Yeah you can rationalise anything if you dream up enough science and explain it with enough made up impressive looking equations. But you have to come at it from the philosophical point of view if you really want to know what's going on. Parallel universes are a fun little idea but that's all they are. They wouldn't exist because if they did, nothing that happened anywhere would ever truly matter. Everything that happens happens for a purpose. Cause and effect, action and reaction. If every possible permutation of everything could happen and just spear off into a parallel universe every time it did, what would be the point of having the physical and archetypal laws that we know to exist? They would be completely undermined. Rather than making silly stuff up, it's better to view quantum as one universe but with infinite possibilities just waiting to stream forth from the quantum flux.

    Doom SauDoom Sau2 dögum síðan
  • I have one major issue with Carroll and that is that he is assuming probability equals reality. "If the universe is infinitely large, then all probabilities become a reality" is me hopefully correctly paraphrasing what he's saying. But just because the maths makes it possible, doesn't make it fundamental. If he were to say, it's possible, but he doesn't. He asserts that if the universe is infinitely large, then all realities are true. But not only do we not know whether that is true or not, it's also not observed, so there is also an infinite possibility of an anomaly ruining his assertion of endless mathematic semantics. I have no doubt he knows a lot more about this than I do, but he hasn't particularly shown anything to prove anything, simply that it's logically plausible. But he's not saying it as if it's just plausible, he's saying it as if it's indisputable, despite being unobservable. Also something that annoyingly doesn't come up is how would the branch of reality physically manifest? Because surely traditional physics still occurs, where are these universes housed and why do they occupy different spaces? What dictates any of that?

    James TravisJames Travis2 dögum síðan
  • That moment when you get to the end of the video and realize Veritasium must not ever have known wtf he ever talked about because he is literally promoting Norton. Or he is working for feds, to help them read your emails. Btw, there is not any branching happening like a new Creation every nanosecond. All of Creation, in all its different versions, with different sets of natural laws in some sets of universes than others, it already exists, all of it, the beginning, the end, the middle, and all the different outcomes. And consciousness is just navigating these seemingly infinite amounts of separate moments in "time" and this navigation, from beginning to end, is what you perceive as time. And when we say they are parallel, well, only to the stuff inside them perhaps, not to consciousness and its points of view, because those points clearly cross from one moment to the next, so why could they not cross over into another timeline and version of perception? Why else would Creation be wired this way? And concerning the contradiction of mentioning "branching" and "parallel" universe in the same video: Look up what 'parallel' actually means in geometry. It means non-intersecting.

    Bryan FreemanBryan Freeman2 dögum síðan
  • In a fractile universe, everything is duplicated ad infinitum.

    John FlemingJohn Fleming2 dögum síðan
  • I don't know enough to follow this. I'm just a philosopher. We're the confused aloof ones asking all the questions then completely zoning out when you try to answer.

    electric_magneticelectric_magnetic3 dögum síðan
  • Here's my question with this, what environment do these "branches" exist in? If the universe is copying itself in that moment, then where does it go? I've seen multiple iterations of this expressed visually but they just exist in a frame next to another, but where is that? You can't just stick it conveniently in a big black box and say space. That and if that's true the entire universe revolves around our own existence and experiences, if our observation of things changes them. So elsewhere on say Neptune, no branches are created because no one is there to observe anything happening, it is solely changed by our experiences on earth.

    goingcommando27goingcommando273 dögum síðan
  • Even if the branching happens infinitely often, it may mean there are limited quantity of branches at every moment ("limited" as in "less unlimited than that unlimited" at least (as we know there are different infinities). Just because different processes may lead to the same result on the macro level.

    LazyLoneLionLazyLoneLion3 dögum síðan
  • I’m not annoyed about branches or something, I’m annoyed that there’s probably someone who used to be me and I used to be him, but he’s rich now and I’m depressed...

    Walter LWalter L3 dögum síðan
  • Someone has to do a joke about a particle walking in and not walking in to a bar at the same time

    Artur KamalovArtur Kamalov3 dögum síðan
  • 192192 manga

    animesquadgpanimesquadgp3 dögum síðan
  • how about matrix

    jemrich gonzalesjemrich gonzales3 dögum síðan
  • But why can’t the cat be an observer collapsing its own wave function? I know it’s just a thought experiment but ...

    TheChickenDuckTheChickenDuck3 dögum síðan
    • :v

      animesquadgpanimesquadgp3 dögum síðan
  • So let's say traveling to a branch was possible. What would happen if someone were to travel to a branch where they don't exist?

    Gabi BezeaGabi Bezea3 dögum síðan
  • It sounds to me like we are too concerned with the stone and the ripples/waves but not enough concerned with the water that forms and carries the waves.

    Peaceful Mind and SoulPeaceful Mind and Soul3 dögum síðan
  • 3,6,9

    Antonio JimenezAntonio Jimenez3 dögum síðan
  • The so called parallel worlds described in this video is all imagination. You can imagine a different version of events. It will never be proven to be true just like if the universe is infinite 16:11. The actual parallel worlds is not actually parallels worlds. It is just the infinite universe 16:25 where the universe is infinite and there are infinitely many earths and humans in it and of course there would be an infinite version of you doing the same thing as you and slightly different things. 11:24 there's no such thing as an infinitely many versions of this world since the total number of ways to arrange planck volumes in the observable universe is finite so there's only a finite number version of things that could happen. The others would just be duplicate of what is happening.

    CarbrickscityCarbrickscity3 dögum síðan
  • What would happen if two waves with the same momentum became entangled? would they go off equally as two different waves or one dig wave going every direction?

    Dj GloverDj Glover3 dögum síðan
  • this is great for watching because i am the highest i’ve ever been

    kart benkart ben3 dögum síðan
  • Man’s mental tools have a long way to go to be effective.

    TallSomeoneTallSomeone3 dögum síðan
  • The legal gun intringuingly lick because pantyhose expectedly dress afore a teeny-tiny hour. hesitant, smoggy kilometer

    Vuk CeklicVuk Ceklic3 dögum síðan
  • The shut microwave intraorally nest because comma supply belong against a solid carpenter. deranged, breezy laugh

    Vuk CeklicVuk Ceklic3 dögum síðan
  • who else came here to learn about parallel worlds and not Physics?

    Sravan TatipalaSravan Tatipala4 dögum síðan
  • Are there parallel worlds where parallel worlds probably don't exist? 🤔

    Oktay ShakirovOktay Shakirov4 dögum síðan
  • This creeps me out

    Prabjot SinghPrabjot Singh4 dögum síðan
  • So you're telling me that somewhere, just somewhere, theres a parallel universe where Trump was a good president and everyone HATED Obama or Biden, there wasn't any virus pandemic, Australia didn't burn down, MrBeast was poor, PewDiePie hit 100 million subscribers before T-Series, I was actually very famous in ISpast and social media as a whole (and so is everybody else), JayStation wasn't cringe and actually posted decent videos which are not clickbait, Morgz wasn't also cringe, Dream only hit 1 subscriber and never understood the ISpast algorithm, Tommy wasn't funny and same thing with Quackity, Wilbur never created L'Manberg, SMPEarth never died but Techno never joined it, Tubbo wasn't the president, George nor Eret was never the king of the Dream SMP, Dream SMP never existed in the first place (and even if it did, it would probably be just wars and no peace AT ALL), 2b2t wasn't a anarchy server and didn't have chaos nor hackers, FitMC NEVER ever made one single 2b2t video, Minecraft Monday wasn't hacked and was still active till this day, Noxcrew never created Minecraft Championship and even if they did, it wouldn't be that popular, Fortnite didn't have such a toxic community, LazerBeam never played Fortnite actually, Roblox was more popular than Minecraft, Microsoft never bought Minecraft, Notch was still the owner, there wasn't any online schools, World Record Egg never got the world record, Bill Wurtz never took such a long break and would still make really cool music videos or just videos actually? Oh wow.

    SonGamesSonGames4 dögum síðan
  • Conjecture

    Drak ScrabulousDrak Scrabulous4 dögum síðan
  • No they dont cause that means a nuke wpuld explode into a parrellel world and they dont do that

    Pa SiPa Si4 dögum síðan
  • ok great video. not a fan of norton though..

    Toni-420Toni-4204 dögum síðan
  • i wish my $600 dollar college courses were this good

    Mark SantosMark Santos4 dögum síðan
    • 600?! Goddamn, lucky you, i pay 5,1k australian dollars per unit :((

      Sebastian BauerSebastian Bauer11 klukkustundum síðan
    • There is a version of you who gets good college courses for 600$

      Frodo BagginsFrodo Baggins3 dögum síðan
    • $600 dollars? Where do I sign up

      Grief PBGrief PB3 dögum síðan
  • In Islam there’s a saying: “God knows what happened and what will be and what will not be and if it happens how it will be”, I think it matches what multi-universe theory is suggesting 🤷🏻‍♂️

    BR 19BR 194 dögum síðan
  • Thank you for creating these videos.

    Dan PedersenDan Pedersen4 dögum síðan
  • Can this be tied into the loa? Can we use this in our everyday life to produce any desired result? Thanks!

    CC4 dögum síðan
  • It’s entanglement is less and less everyday more and more by the professing of knowledge and people; some, exploring, some believing, But your most fine eyed cognitive dissonance that is, hidden from sight. Is only hidden from the one who would take it. But however Cannot. It can only be given. Freely. Einstein didn’t just believe in god because he was Jewish. And the Christ can be viewed in him by his choices. Especially, the ones made during the infiltration of the nazis; and they’re agenda. Now, was time held back?? Were measurements made?? And finally did I ask you to give something up without holding back your dissonant atoms ⚛️ for you to reach your conclusion ,s fundamentally, you exist but the key 🔑 to all atoms ⚛️ is.. ? 🧬 this wonderful chain of commands and If nothing else, it’s mere shape will guide the hand of conclusion. Thank you and goodnight. Omega man 👨

    Malcolm AdamsMalcolm Adams4 dögum síðan
  • “Unbelief is the only hinderance of true science. “ 🧬

    Malcolm AdamsMalcolm Adams4 dögum síðan
  • Parallel words suggested by the capitalist information system. Brought to you by.. Father son Holy Ghost 👻 and they all say yes it’s true, there is a spirit world 🌎that runs parallel to our own. And the critters that operate and or destroy within said parallels may or may not be called angels and dæmons.

    Malcolm AdamsMalcolm Adams4 dögum síðan
    • Now ask your faith question. Then stop purposing the latter because if you do not then fourth wall dimension comes into effect and your enlightenment is only fourthcoming of your prideful nature. Ask me how I know??

      Malcolm AdamsMalcolm Adams4 dögum síðan
    • Golden ratio. Newton’s law within that will give you the power needed to figure out this and the gravitas upon your parallel universe. After that I am unwilling to invest in this [m] ore than I already have.

      Malcolm AdamsMalcolm Adams4 dögum síðan
  • Thumbnail looks like a artificial fully connected neural network.

    techtamtechtam4 dögum síðan
  • Meanwhile in a parallel universe: 「Dirty Deeds Done Dirt Cheap」

    BlazingStorm8895BlazingStorm88954 dögum síðan
  • A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms shall not be infringed.

    Andrew RAndrew R4 dögum síðan
  • If a 4. dimension in space is added, it could be interpreted in several ways. One of them are that we can only observe what happens in our 3D. A 4D object will only be observed in 3D when the 4. D is fixed in the right position. Like a 3D object placed into a 2D world. The problem with this is that we should have observed energy-transfer from 3D into 4D. But this needs not be a problem as long as the transfer is in sum zero in a small enough time and space. Then it could be overlooked. Just some thoughts.

    Asgeir NilsenAsgeir Nilsen4 dögum síðan
  • Comment section is suspicious like government spy suspicious

    Daniel sonDaniel son4 dögum síðan
  • Probably isn't good enough. God has GUARANTEED that no one will ever be able to provide the NAME and LOCATION of another planet that is inhabitable and inhabited by plants, animals, sea creatures, and human beings. In A universe of billions of stars and planets.

    James CurtisJames Curtis4 dögum síðan
  • There is a version of me that thinks that some of these comments were written by people who actually know what they are talking about...that group, however, is VERY small. Those who tossed politics into the discussion are NOT in that very small group.. they actually should butt out of the conversation.

    John AshtonJohn Ashton4 dögum síðan
  • Probably.

    psickopath psickopathpsickopath psickopath4 dögum síðan
  • They really probably do not exist. The whole theory is lacking one decisive moment: Superposition is valid for microobjects only, strongly speaken for elementary particles(quants). Universes however are macroobjects. Macroobjects are always in a clearly defined state. A given universe may exist with a certain, bigger or smaller likelyhood. But when it exists then it is the result of the interaction of all of its containing microobjects. The single microobject may be in the state of superposition but the universe is not. You can also say that all the microobjcets measure each other steadily destroying their superposition. This destruction of the superpositions within a macroobject is called: "existence". Schroedingers "experiment" with the cat in a box was nothing but a joke to show how absurd the world of quants is. In the real(macro) world the cat is either alive or dead, no matter if someone will open the box. If nobody opens it at all they will smell it when the cat is dead finally.

    Holdin MuhlHoldin Muhl4 dögum síðan
  • I believe on good old: God dont gamble. Even small world is deterministic, but we cant ever know how it works since its like to you try to measure movements of apples with bowling balls

    srksiisrksii5 dögum síðan
  • I’m not a quantum physicist, but Many Worlds it is the result of people not being able to come to terms with the fact that we don’t understand the superposition of particles and how they relate to waves. It’s like someone said “why are the waves and particles acting like this? Must be infinite parallel universes.” Shrodingers equation is incomplete, in fact every great quantum physicist has said something along the lines of “if you think you understand quantum mechanics, you don’t understand them at all.” The apparent duality of quantum “particles” is not evidence of infinite parallel universes with different webs of quantum entanglement, it’s evidence that we have no idea what we’re looking at. It’s irresponsible that we even call a quantum particle a particle, because it shares very very little in common with a physical particle. I do believe in parallel universes, but I don’t believe our simple confusion at quantum mechanics is evidence of them.

    Kama LlamaKama Llama5 dögum síðan
  • According to Quantum mechanics.. applied to non-quantum mechanic environment. really "scientific" :)

    Peter NovýPeter Nový5 dögum síðan
  • Meanwhile in a parallel universe, Error 404 Universe is dead!

    Kushagra RaiKushagra Rai5 dögum síðan
  • I’m going to have to watch this a few times. Very heavy stuff. Not sure about the validity of Schrodingers Cat, if he did try this in reality he would ha e died due to cat scratches. Have you ever tried to put a cat in a cat box. I have pondered the thoughts of multi universes for every eventuality but I think there’s no way that could be possible as the numbers are too big. It’s really thought provoking stuff.

    Shane's Queen SiteShane's Queen Site5 dögum síðan
  • Cat: *I'm alive but I'm dead*

    manda ACmanda AC5 dögum síðan
  • I've been to the other worlds. dmt is the doorway.

    Tom Beats BeatsTom Beats Beats5 dögum síðan
  • There is only one atom. Only one atom exists.

    Tom Beats BeatsTom Beats Beats5 dögum síðan
  • It's a wave with low Q.

    Tom Beats BeatsTom Beats Beats5 dögum síðan
  • What part exactly was sponsored by Norton?

    Tom Beats BeatsTom Beats Beats5 dögum síðan
  • Why not try the Cat experiment in lab ?

    Raghavendran T BRaghavendran T B5 dögum síðan
  • Hindu scriptures have mentioned about Multiverse concept several centuries back.

    Raghavendran T BRaghavendran T B5 dögum síðan
  • Parallel worlds!? Can you tell me how we to can reach into a so parallel world where don't exist coronavirus?

    hgjf3hgjf35 dögum síðan
    • Be at light speed, and wait for the humanity to reach its epitome in technology and science

      Kushagra RaiKushagra Rai5 dögum síðan
  • So is the universe basically a giant logistics map? Was the first ever entanglement/interaction the first branch on the logistics map? Then doubles, then chaos, with occasional coordination?

    Mackenzie SMackenzie S5 dögum síðan
  • Im not trusting.Because science cant proof it.And ı think never explain it.

  • Wait so they’re entangled even millions of light years away? Are each entangled with everything else

    Luciano ArebaloLuciano Arebalo6 dögum síðan
  • There are different realities where I have done all those things where you're like "what if I jumped off this cliff?".

    Link LinkLink Link6 dögum síðan
  • I wish it's true, because in theory, I could easily genuinely get superpowers.

    Link LinkLink Link6 dögum síðan
  • Great information but so boring to watch and better delivery needed for a normal layman to understand

    Dr J SinghDr J Singh6 dögum síðan
  • No. I don't think so. But interesting.

    Troy ClausTroy Claus6 dögum síðan
  • so you're telling me something can be different when we're looking from when we're not looking oh god the weeping angels are real aren't they

    Abbe NylundAbbe Nylund6 dögum síðan
  • Hi This is another version of myself writing this comment, but please don't tell my original version that I'm using their computer because they would be mad.

    Bechara KreidyBechara Kreidy6 dögum síðan
  • The largest natural number is 10^100000. Its a finite system that runs infinitely and there is no indication whatsoever that there are others out there. What matters in this is that you eternally reincarnate into every possible body living every possible life, eternally, and that you in fact ARE both the Multiverse and every single aspect of it. So, since the Other is You in another lifetime, treat each other right and strengthen your ties with your close ones.

    SpiritworkerSpiritworker6 dögum síðan
  • So what happens when you're faced with 3 possible outcomes? 🤔

    Trav PTrav P6 dögum síðan