The Quantum Theory that Connects the Entire Universe

  • Published on Mar 20, 2019
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    Quantum mechanics is weird and seems a bit...complicated. But understanding it can help us to understand the universe.
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Comments • 1 279

  • SciShow
    SciShow  3 months ago +71

    SciShow is supported by Go to to get 20% off of an annual Premium subscription.

    • Josh Lasky
      Josh Lasky 2 months ago

      Scishow...paid for by Deepak Chopra lol

    • Dadson worldwide
      Dadson worldwide 3 months ago

      The fact we the observer are at the center of the universes is the samething mans known forever .

    • gdpr
      gdpr 3 months ago

      wtf, if you are stupid but you dont know it yet it does not mean you are not stupid !, how does the pilot theory has anything to do with locality ?!, or your missinterpretation of it ? wtf is wrong with you , haa ? if you spin 2 electrons in opposide directions YOU ALREADY KNOW THEY ARE SPINNING IN OPPOSIDE DIECTIONS, you just dont know which one is spinning in which direction, so as soon as you find the spin of one electron you combine that WITH THE INFORMATION YOU ALREADY HAVE and determine the spin of the second one, this has nothing to do with locality, it does not matter where you Move the second one, you already have the information. htf can smart people be this dumb ? are you so desperate to fin an explanation that you simply ignore parts of the ecuation to fit the result you already expected ?!

  • Ali Kafafy
    Ali Kafafy 2 days ago

    Wow that cat is wanted dead or alive

  • M Man
    M Man 2 days ago

    The Schrodinger problem always had this one thing that put a wrench in the whole program the fact that the cat was living before you put it in the box it is able to make its own observations unless you poked both of its eyes out put a blindfold sounds like it would be a lot less harmful to the 🐈

  • Tippi B
    Tippi B 6 days ago

    I had the frustrating experience of understanding quantum mechanics for about 12 seconds and then it slipped away from me. I, a lowly writer of TV show reviews, was at the dog park talking to NASA scientists (I lived down the road from the Johnson Space Center) and I made a quantum mechanics joke. Except... I no longer remember the joke. It evaporated out of my mind as soon as I finished. But I do recall that the NASA people laughed heartily and said it made sense.

  • Devon Carter
    Devon Carter 6 days ago

    Just saying that if the pilot wave theory is true that would mean travel faster than the speed of light

  • Zoë de Wijn
    Zoë de Wijn 8 days ago

    but wouldnt the cat be able to observe weather or not the superposition happened and the poison got released, and therefore it would be only one of those things and not both?

  • iMeMyself
    iMeMyself 9 days ago

    System call: generate quantum element. Form photon. Discharge.

  • Genave NNMN!
    Genave NNMN! 11 days ago

    Sheldon bring me here.

  • Vinish
    Vinish 12 days ago

    Is that string theory?

  • Mavrick 1975
    Mavrick 1975 12 days ago

    With scientist finding more and more things on the subatomic level I was wondering about beyond what we know now. If we can calculate the weight of a shadow and their is technically nothing their if you truly tried to create a vacuum and remove all known particals down to the quarks is it truly empty or is nothing made up of something?

  • altareggo
    altareggo 17 days ago

    Trump supporters are perpetually interposed in the narrow space between conspiracy theories and "alternate facts".

  • J. Bearding
    J. Bearding 20 days ago

    The distance between the sun and the black hole of our universe is spaced the same distance equal to the golden ratio, allowing gravitational balance.
    The sun is powered by the destruction of the black hole. That is why the sun will not change without the input of the black hole equally changing.
    Makes sense, no?

  • ykOni
    ykOni 28 days ago

    What is this world?

  • Maldus Alver
    Maldus Alver 28 days ago

    time to play a game of quantum tic-tac-toe

  • Kaveevin
    Kaveevin Month ago

    The more quantum mechanics videos I watch, the more evidence I get that we're all living in a simulation.

  • johnathan blevins
    johnathan blevins Month ago

    U guys should start sci show for dummies

  • Fitness and Firearms

    My girlfriend was right. I am TOO high for this. Great video! Im subbing

  • Jason Hacker
    Jason Hacker Month ago

    Zombie cat video?

  • rogerdotlee
    rogerdotlee Month ago

    Now wait a minute. About superposition, the premise of the experiment is that you generate two electrons that MUST be spinning in the opposite direction. You then move them a couple giga-furlongs away from each other. You observe them and find they're spinning in opposite directions. Unless I'm missing something fundamental, the only reaction to this should be 'well duh! This tells me our electron-spin-generator is functioning as expected.'

    What am I missing?

  • Neo2266
    Neo2266 Month ago +1

    It’s Schrodinger, as in “Dingus”

  • Forever Evolving
    Forever Evolving Month ago

    Superposition is possible because of the multiverse.

  • Anup Gamer
    Anup Gamer Month ago

    You should have sub tital

  • Paul Gardner
    Paul Gardner Month ago

    One of the best videos you've made!

  • Dred Cthulhu
    Dred Cthulhu Month ago

    Something I’ve always had an issue with, wouldn’t the cat be able to observe itself? Ergo it’s one or the other, not both. I’m not a physicist so I have no idea. But logically the cat would be the observer right?

  • johan erik theodor clemmesen

    I live in Copenhagen Denmark. It's a super position to be in.

  • Joey Lochart
    Joey Lochart Month ago

    pilot wave is only theoretical.. across the emptiness of space, the pilot wave is dead.. its like a discontinuous layer between masses.

  • Joey Lochart
    Joey Lochart Month ago

    electrons resonate when seperated because they were connected, so their wave lengths did interact closely at some point. this would have some cause and effect on their spins that might cause them to resonate, even when further apart and seperated. that's my speculation.

  • Holl E. H.
    Holl E. H. 2 months ago

    So when I wish on a star, it gets there at 2 different rates? (Immediately and only at the speed of light?)

  • Dan Zuck
    Dan Zuck 2 months ago

    Very clear; nice. Thanks.

  • Toad Roach
    Toad Roach 2 months ago

    So if a tree falls over in the woods and there is no one around to see it, has it actually fallen over?

  • SFaPiL2
    SFaPiL2 2 months ago

    I dont know the underlying math in pilot wave theory but, by the way that it's being explained, it reminds me of modal analysis and other studies I've done in signal analysis during my engineering degree.
    Rather than thinking of the two particles being interlocked independently from space (indicating information travelling at extremely high velocities in order to guarantee their states are interlinked) couldn't it be that they normally match a "wave" which is independent from space itself? A "natural frequency", if you will accept my analogy with modal analysis, where these particles fit in the nodes of such waves; hence retaining a similar behavior as long as they stay fixed to the nodes of this wave independent from time and space.
    In order for this to be valid, though, an infinite number of particles all fitting in separate nodes of this hypothetical "wave" would all retain the same properties of the particle under test.
    Does anyone more knowledgeable know whether this analogy I brought up is a load of garbage or not? ;P

  • Existenceisillusion
    Existenceisillusion 2 months ago

    2 things.
    1) QM properties of individual particles contribute to the QM properties of larger ensembles, and above some threshold ensemble size, the QM properties "smear out" (else we would have to choose which contribute and which don't), resulting in the classical properties we know and love.
    2) I think it's Bell's theorem that showed that entanglement is more than just deduction. I.e., if we know there are a total of two states and two particles, and after separating them, we observe one, we subtract the observed state from the list of possibilities, leaving only one state possible, thus not requiring FTL info. Bell's theorem showed this is not true...if I remember right.

  • Patrick Mcguire
    Patrick Mcguire 2 months ago

    Our simulation overlords dictate the rules that guide their universe..we are just along for the ride 😂

  • kiss my dirty ass
    kiss my dirty ass 2 months ago

    Send me computer free😂😂😂honestly

  • MJ Music
    MJ Music 2 months ago

    I’ve said it before and I’ll say it again. It

  • blubastud
    blubastud 2 months ago

    Why does this sound like quantum entanglement?

  • Hyacinthus
    Hyacinthus 2 months ago

    Copenhagen throws out both determinism and locality, Pilot Wave throws out locality. In no way does the Copenhagen interpretation make more sense than Pilot Wave theory.

  • Theⱥωesoͥϻeͣgͫ
    Theⱥωesoͥϻeͣgͫ 2 months ago

    So... Ockham’s razor?

  • Shaboopy
    Shaboopy 2 months ago

    The copenhagen interpretation just seems like a place-holder until the fuller picture can be hashed out.

  • John Walker
    John Walker 2 months ago

    Your gender is in Superposition.

  • Owen Eastwood
    Owen Eastwood 2 months ago

    But what defines an observer/observation? It can’t be that something requires a living thing to observe it in order to change, so what’s actually happening here?

  • Jons LG
    Jons LG 2 months ago +1

    The shroedingers cat experiment is a horrible example imo, unless you're trying to prove that the particle is indeed in one state or another..
    Because you don't actually change the cats state by measuring it. The cat is indeed either alive or dead, and the only thing that changes is your knowledge, as the measurement has no effect on the cat.

  • zainab alshammari
    zainab alshammari 2 months ago

    Very good job on explaining such a weird yet correct theory .. it's the brain food I'm looking for!

  • EmptySora_
    EmptySora_ 2 months ago

    I love all the videos on SciShow but the quantum mechanics ones are always among my favorites.

  • Daniel 777
    Daniel 777 2 months ago

    My question is has anyone studied Seashells, with Quantum. I remember listening to the echoes of the Ocean younger.

  • Eric McGuinness
    Eric McGuinness 2 months ago

    Super position.....but when ever in the universe is something not being observed by or interacting with all the other particles, energies and forces around it? When is something ever completely isolated? Doesn't make sense to me but what do I know.

  • Seán O'Nilbud
    Seán O'Nilbud 2 months ago


  • Igi Vup
    Igi Vup 2 months ago

    Sperm cells are particles and waves at the same time... Just sayin.

  • jeffwads
    jeffwads 2 months ago

    Nothing is random. If you have all the variables, you will be able to calculate the event completely. The cat experiment is ridiculous. The cat would be either alive or dead. The observation aspect is moot because you are outside the box.

  • Zes
    Zes 2 months ago

    no such thing as connecx or not

  • Matlab Tutor
    Matlab Tutor 2 months ago +1

    i am still not getting it --- The dead and alive Cat *** I mean we can use the argument in many classical experiments like The example of Dice ???? i dont know why the Cat's example is a big deal for quantum mechanical particles????

  • xxDrain
    xxDrain 2 months ago

    By now all those cats have knocked the vial over themselves and they're all dead.

  • Ken O
    Ken O 2 months ago

    "Reality, what a concept! "-Mork from Ork (Robin Williams). But when it comes to quantum mechanics, the question is, Which reality?

  • Krazy Maniak
    Krazy Maniak 2 months ago

    What if you put the cat into a glass box

  • merlopick
    merlopick 2 months ago

    Schrodinjer?? @3:48 "every expiriment"??? How the hell does this guy talk???

  • Russell Alson
    Russell Alson 2 months ago

    Could anyone explain why most scientists decided Copenhagen? Its seems to me both have just as crazy cons (cat dead and alive analogy or all particles effect each other in the universe)

  • H Missy
    H Missy 2 months ago +1

    What if nothing is ever fixed, and your perception is the only thing that makes it SEEM like it's fixed?

    TROUBLE CAINE 2 months ago

    YOU WERE very wise to SHOW your words in the graphics to aid understanding. This channel is always getting better...!!

  • Gristle Von Raben
    Gristle Von Raben 2 months ago

    Actually the rudimentary roots of laser light research comes from crystallography, sapphires and rubies create a strange star effect simetimes. We typically use rubies to make lasers by pumping light into a reflective cylinder and aligning the crystal so that it bounces light to the front and back of the cylinder until it comes out of that tiny area of the ruby that only allows a thin plane of light to exit. Quantum theory helped explain it, not to create it, correct?

  • tonz lang
    tonz lang 2 months ago

    "theory" why do scientists do not get that?

    CHEVASIT HOMPA 2 months ago


  • Critico
    Critico 2 months ago

    Peter fills a bottle with a pitcher and put it in the trunk of a car. Mike, who doesn't know whether the all or half of the water is poured, drives the car for 10 miles. Before he stops and checks the bottle, the pitcher back a the starting point can be either empty or half full. That, however, is only the case in his knowledge space. In Peter's knowledge space, the amount of water still in the pitcher is already known. The information doesn't teleport 2 miles instantly when Mike opens his bottle, it's just that he doesn't know it yet.
    Should there be any information that travels, it should be inside Mike's brain, not over 10 miles, and It takes time to deduce that half a bottle means half a pitcher.
    Say if the universe is run on an engine inside a computer, and it can be paused to examine the exact speed and position of any particle. Then the information is there all the time, we just have no way to get it. It's beyond our knowledge space, which is limited by our methods, not necessary beyond every intelligent being's knowledge space, nor beyond the universal/absolute knowledge space, should there be one.
    Photons that interact with the pitcher carry information for a suitable observer. The bottle that got carried away can be said to contain extractable information. These carriers of information don't travel instantly.
    The knowledge inside the brain can arguably be considered information, but this conscious information(knowledge) should not be confused with physics information. If a bird knocks over and empties the pitcher after Mike leaves, it will be possible that Mike sees a half full bottle and thinks that the pitcher is half full. How then, can he get a wrong information, which teleports back to the pitcher?

  • Adam G.
    Adam G. 2 months ago

    Regarding the speed of light being the universal speed limit for everything... we've already proven you can cheat that. By bending space/time you can cheat by moving between two points without the travel time between them. Makes sense that particles may be able to do that too... right?

  • Justin Nehls
    Justin Nehls 3 months ago

    David Bomb. Bombian mechanics

  • Sim 303
    Sim 303 3 months ago

    it almost come down to chaos/creation vs scripted/mainframe...quantum mechanics and philosophy,in the same room.

  • Aiden Watler
    Aiden Watler 3 months ago

    What a good episode! I realise this will likely be lost in the sea pf comments, but this was so good and not quite as intense as Space Time. More SciShow Physics videos please!

  • Jordan
    Jordan 3 months ago

    Yeah but things can effect things not in thier immediate surroundings without sending a "traveling" signal or message. You have seen this it's called gears. Gears all start turning see the same time with a little gap for the space between the teeth. The universe often functions like waves making particles because inertial energy gives a portion of existing fabric of the universe mass. Like a set of gears though an already excusing standing waves that have created a network of simultaneously moving parts can communicate information in the form of specific inertia to make it look like a partial was at one end and then just appears at the other end. This duplicate however simply interacted with something like this at one end and communicated it's inertial energy to the other end instantaneously. Similarly entangled particles are capable of staying entangled by creating a standard wave along it's path as the two entangled particles travel apart and when one is flipped on the other end the information initially is communicated via spooky action without the usual need for time for a traveling wave to communicate the effects of that traveling inertia on it's immediate surroundings.

  • V
    V 3 months ago

    Yay, non-orthodox interpretations of QM :) do er=epr next!!

  • Nehmo Sergheyev
    Nehmo Sergheyev 3 months ago

    I am soooo tired of educators, particularly ones on RUclip, using "weird" as a quantum mechanics adjective. Those guys are the truly weird.

  • iVardensphere
    iVardensphere 3 months ago

    The Copenhagen Interpretation doesn't violate locality.

  • WormholeJim
    WormholeJim 3 months ago

    Ugh, I like cats. In my ideal world I would end getting eaten by one, that's how much I like them. So I'm not too fond of that guy Schrödinger. Luckily there's another example (maybe devised by a cat-lover) that shows much the same, and actually at the same time gets to examplify entanglement. Instead of cats you have two friends, two identical boxes and two equally proportioned balls, one red and one white. Your one friend now goes to the opposite end of the world while your other friend grabs the boxes and the balls and takes them with him to a place equally far to both of you and your first friend. He now puts each ball in each identical box and brings them to the post-office with a note, please mail these boxes to these receipients. The clerc then, upon coming back from lunchbreak, writes your adress on one box and your friend's adress on the other and sends them off in the system. A couple of weeks later each box have arrived at their destinations, half a world a part. Right now, *both* balls are in a superposition due to the Copenhagen interpretation. The minute - the second, nay, the split-nano-femtosecond - you open your box and look inside it, the state of the ball will decay into being either red or white. Just like with the cat and it's highly elaborate scheme to ensure maximum randomness. But on top you at the same very instant have caused the state of the ball that is in your friend's box to decay as well - even without him neccessarily having looked yet! Entanglement, ta-daa.

  • The Void Alchemist
    The Void Alchemist 3 months ago

    The machine releasing the poison observes the atom causing a collapse of the superposition, thus no quantum cat required.

  • Mark Marcum
    Mark Marcum 3 months ago

    Could entangled particles be connected by tiny wormholes? That would explain the instantaneous transfer of information? Sorry if it's a dumb question

  • Mark Marcum
    Mark Marcum 3 months ago

    Still watching the video and it's amazing! How about a collaboration with PBS Spacetime?

  • the_armada
    the_armada 3 months ago

    I know pilot wave theory makes certain things nicer to think about while makes other things messier, but I’m a Copenhagen man:)

  • Pat Black
    Pat Black 3 months ago +1

    Our theories are also “guided by aesthetic and pragmatic choices”
    I love you, SciShow. This is such a simple yet effective demonstration of just how foggy the frontier of our exploration of reality really is.
    It’s a strange world with stranger questions arising every day.

  • Dadson worldwide
    Dadson worldwide 3 months ago

    You still have to send the entangled particles to were you wish to communicate.

  • Walter Archibald
    Walter Archibald 3 months ago

    SHROW-ding-erz OR watch:
    oder (auf deutsch, mit umlaut):

    This name is heard endlessly in American English (ex. The Big Bang Theory), using (basically) what I put first. It just "sounds right" to Americans.

    BUT, WHAT IS TRUTH? (Really wish Jesus had said that, rather than Pontius Pilate!)

  • TheIntJuggler
    TheIntJuggler 3 months ago

    "Newtonian physics is weird" Quantum Mechanics

  • quest 77051
    quest 77051 3 months ago

    so does sub space exist or not.

  • Draws Gaming
    Draws Gaming 3 months ago

    What if the Pilot Wave interpretation is correct and locality must be sacrificed to solve the Bell Inequality?

  • John Galdino
    John Galdino 3 months ago

    Doesn't gravity according general relativity already break this locality rule? Is that why there is so much search for gravitons?

  • Saumitra Chakravarty
    Saumitra Chakravarty 3 months ago

    Correction needed at 1:37 - Something can be a particle and a wave both but NOT at the same time.

  • Jim Goltz
    Jim Goltz 3 months ago

    I thought the Copenhagen interpretation wasn't popular these days...?

  • El Triggered
    El Triggered 3 months ago

    Where’s Olivia

  • M ß Q
    M ß Q 3 months ago

    This video is definitely going to exceed 1M views in less than a month

  • Engin Haymana
    Engin Haymana 3 months ago

    Doesnt that just mean that we need better methods to "observe" particles, as doing so alters the results?
    We live in a deterministic world, so i find it very hard to wrap my head around that concept.
    Its like chaining the poison gas to the opening of the door. Sure, you have observed the status of the cat, but also changed the state of the poor cat. The original state has not been uncovered, but the information of that state is still there.

  • Keaton Smith
    Keaton Smith 3 months ago

    Pilot wave theory sounds like Dao.

  • Vitor in_Berlin
    Vitor in_Berlin 3 months ago

    I think it is important to keep in mind, that the different interpretations of quantum theory are models describing real quantum phenomena!
    Most likely, there is no definitive interpretation, because no physical (or - to my best knowledge - any other) model, was ever able to capture every part of the phenomenon it described in all detail on all scales.
    That's why science relies on various models of the same phenomenon, each with emphasis on different parts (or scales) of said phenomenon.
    The real question is, which models are able to coexist without fundamental contradictions to each other.
    I don't think that the different interpretations of quantum theory show these fundamental contradictions, even if that appears to be the case!
    The key flaws in humanitie's ability to solve those contradictions and create a more accurate approximation to real quantum phenoma lies in it's limited perception of the phenomena themselves and time as a phenomenon which is described by a model based mostly in human perception of it.
    My suggestion would be, that most of the different interpretations contradict each other, because the describe quantum phenomena with emphasis on their observed (or predicted) behaviour in different temporal dimensions.
    For example, lets take the many-worlds-interpretation and the wave-collapse-interpretation (or Copenhagen interpretation):
    The collapse of a wave function into a particle, or the termination of a state superposition in a particle and it's adaptation of a single state with an elimination of all other possible states, allows two (or more) interpretations based on how many temporal dimensions one can observe.
    Human beings experience time as one dimensional. Their frame of temporal perception is a single point on a line, where what lies behind is inaccessable and what lies in front is unpredictable but unavoidable.
    From this point of view the assumption, that every state of superposition we are not able to observe after the collapse of the wave function is eliminated from the equation, is fully understandable.
    But if we assume that time is/has a multidimensional 'structure' (which most evidence points to), and try to imagine what the collapse of a wave function looks like for beings with two dimensional perception of time:
    Instead of the 1D-perception of a moment in a timeline and the elimination of states in the collapse, a being experiencing two temporal dimensions, would perceive time as a (freely accessable) line in plane (with inaccessable parallel lines) and in this frame of temporal perception, the collapse of the wave function would most likely look like all possible states of the particle are spread among all the parallel lines, observable, but inaccessable.
    To summerize this:
    0. Quantum phenomena (and every other processes) occur in a multidimensional temporal structure.
    1. The wave-collapse-interpretation is a model, which describes these phenomena as observed in one temporal dimension.
    2. The many-worlds-interpretation is a model, which describes these phenomena as (likely) observed in (at least) two temporal dimensions.
    3. Each interpretation serves best, when applied in it's specific frame of perception and holds scientific plausiblility, when viewed in in said specific frame of perception, without contradicting each other fundamentally.

  • feekygucker
    feekygucker 3 months ago

    I always that Bohm rhymes with Ohm rather than Nom... but it could be me.
    Also... shout out to PBS SpaceTime that has a MUCH deeper treatment of this material over MANY videos.

  • Jacob Johnson
    Jacob Johnson 3 months ago

    I don't like copenhagen's. Its self-contradicting. That's logically wrong.
    Pilot wave theory doesn't break the law of non contradiction, its simply counterintuitive to how we are used to thinking of things.

  • Mick G.
    Mick G. 3 months ago

    "The physics of the super tiny" is the worst description of QP, I've ever heard.

  • Chillman
    Chillman 3 months ago

    It can't be predicted... yet.

  • Waylen Edge
    Waylen Edge 3 months ago

    This is by far the most dumbest video ever made!

  • Daniele Del Frate
    Daniele Del Frate 3 months ago

    First part of the video: well, this pilot wave theory seems legit
    Second part of the video: pilot wave theory is insane!

  • Shalkar
    Shalkar 3 months ago +3

    With String Theory there are multiple dimensions. Couldn't the signal be from one of those dimensions? Think of Night Crawler going through one dimension to go to another spot in ours. We just haven't figured out how to "see" the dimension... yet.
    Also, what if Dark Energy/Matter is playing some role in this?

    SIIIOXIDE 3 months ago

    Damm , here I was thinking I was the center of the universe this whole time :'(

  • TCOrigamist
    TCOrigamist 3 months ago

    But what if you were the cat?

  • Joshua Champagne
    Joshua Champagne 3 months ago

    I have a question on how to get around locality. If a wormhole can connect any to points in the universe, could two particles interact through a wormhole giving the illusion they are interacting across the universe faster than light? Can the particles on each side of the wormhole be considered local because they can interact? If so, any particles can interact with any other particles in space meaning any point in space would be local to any other point in space making all of space local.

  • Alexander Hugestrand
    Alexander Hugestrand 3 months ago

    Can someone please tell me why quantum mechanics and the wave particle stupidity isn't a shitload of crap, and why the following extremely intuitive explanation is?