The True Science of Parallel Universes


Everyone loves the idea of parallel universes
– maybe it’s the appeal of an ideal world where you have second chances and things turn
out differently – an alternate reality where you do get into Hogwarts and the Star Wars
prequels aren’t made and you finally plug in your asymmetric computer cord correctly
on the first try… but is there really a place in science for such wistful speculation? I mean, if “the universe” is everything that
there is, you can’t have two versions of it, right? Otherwise the pair would really be
everything and what you started off calling the universe, wasn’t. The problem here is terminology: physicists
speaking informally often say “universe” when they really mean “observable universe” – that
is, the part of the whole universe that we’ve so far been able to see. And it’s perfectly
fine to talk about multiple different observable universes – for example, an alien near the
edge of OUR observable universe will see parts of the Whole Universe that we cannot yet see,
but that’s a well-understood question and not what physicists normally talk about when
they discuss multiple observable universes, or “multi-verses.” So let’s cut to the chase: in physics, the
word “Multiverse” normally refers to one of three distinct and largely unrelated proposed
physical models for the universe – none of which has been tested or confirmed by experiment,
by the way. The three “multiverse” models are: Type 1) Bubble universes or baby black hole
universes. This is the most straightforward kind of multiverse: the basic idea is that
perhaps there are other parts of the universe which are so far away that we will never see
them (or are inside black holes so similarly we will never see them).
This kind of model was created as an attempt to explain why our universe is so good at
making stars and galaxies and black holes and life – as the argument goes, if each of
these separate mutually un-seeable “bubbles” in the universe had slightly different laws
of physics, then by definition we could only exist in one that had the right physical laws
to allow us to exist. If you’re not convinced by this logic, don’t worry too much: there’s
not yet any experimental evidence for this kind of multiverse.
Multiverse type 2) Membranes and extra dimensions. Inspired in part by the inability of the mathematics
of string theory to predict the right number of dimensions for the universe in which we
live, string theorists proposed the idea that perhaps what we think of as our universe is
actually just a three-dimensional surface embedded within a larger super-universe with
9 spatial dimensions. Kind of like how each page of a newspaper is its own two-dimensional
surface embedded within our three-dimensional world.
And of course, if space had 9 dimensions rather than three, there’d be plenty of space for
other three-dimensional surfaces that appeared, like ours, to be universes in their own right,
but, like the pages of a newspaper, were actually part of a bigger whole. These kinds of surfaces
are called “membranes” or “branes” for short. And as a reminder, there is not yet any experimental
evidence for this kind of multiverse. Multiverse type 3) The many-worlds picture
of quantum mechanics. Surprisingly, physicists still don’t fully understand how the collapse
of the wavefunction in quantum mechanics happens, and the many-worlds hypothesis makes an attempt
at explanation by proposing that every possible alternate timeline for the universe is real
and they all happen in an ever-larger, ever-branching way. Like, a universal choose-your-own-adventure
where every possible story happens! If this were the case, we might not realize
it because we’d be stuck living out just one of the infinitely many possible lives available
to us. In some ways, many-worlds is similar to the bubble multiverse model by proposing
“maybe anything that can happen, does. And we just happen to exist in the series of happenings
that were necessary for us to exist.” If you’re still not convinced by this logic, don’t worry:
there is not yet any experimental evidence for this kind of multiverse. Of course if you want to get imaginative,
you could also combine several of these models together into a multi-multiverse… a new
super-speculative model based, itself, on speculative and experimentally unconfirmed
models. But that’s not to say we couldn’t test these
multiverse hypotheses. For example, if our observable universe were really just one of
many disconnected bubbles or membranes and if it happened to collide with another bubble
or membrane some time in the past, then that collision would certainly have had some sort
of effect on what we see when we look up at the night sky.
On the other hand, the many-worlds interpretation might be tested fairly soon since experimentalists
are becoming increasingly able to manipulate and control ever-larger quantum mechanical
systems in their labs – systems that approach the line between the quantum realm and our
everyday experience. So as always, we must remember that physics
is science, not philosophy; and in our attempts to explain the universe that we observe, we
have to make claims that can in principle be tested – and then test them!

100 thoughts on “The True Science of Parallel Universes

  1. What if there is another universe in which God exists and scientists from another universe (not the same one) knew about him before he knew about them…

  2. There is an universe where you are inmortal… It isnt this one tho

  3. I quit the video after 10 seconds when it says star wars' prequel shouldn't have been done.

  4. And then we get the conspiracy theory that deja vu is just our brain letting us know "there's another ending for that"

    Think about it, when was the last time you had deja vu? (If you have it) Was it in your car? If so, where in your car? Where was the car?
    Were you driving on the road in the front seat? If so, in a separate universe you could've crashed at the moment, or your favorite song came on… Or both!

  5. The third theory remembers me about Men in Black 3 because there is this Alien Species which can see every possible future at once.

  6. I kind of hope alternative universes exist. So I can have a brawl with myself and confuse the police

  7. In another world you would be hit by a truck in this moment. And then transport to another world.

  8. I Think that the universe expand and shrink cus of the dark stuffs weight but I also believe that there can not just be a wall and then everything ends there so i think that there is ♾ universes laying rigth next to each other doing the Big Bang and the Big Crunch again and again in that way everything happens every second

  9. 2013: no
    2014: nope
    2015: nahh
    2016: later
    2017: no
    2018: wait for it
    2019: there you go

    I wonder if there is an alternate Universe where I watched before

  10. If our 3D universe is contained ina 9D universe. Then, our universe would be a 3D universe in a 4D space inside of 9D universe.

  11. I think about this a lot. Probably unhealthily much. Mostly in the context that fictional worlds are worlds parallel to our own. Somewhere out there is Spider-Man and goku fighting to protect their worlds… (would gojis universe be comprised of all the 14 universes that make up his worlds existence, and all that would be part of just one parallel dimension?)
    I wish I’d be alive at the time that they’d discover or even travel to new dimensions and planets and stuff

  12. Every decision you didn't make is an alternate universe.

  13. Dislike. The idea of existing an universe where the precuels weren't made makes me so sad

  14. Strangely, I'm more inclined to the 3rd theory where at every split road of choice, the universe splits and based on your choice, you will exist in either of them. o.O

  15. I read a short story once that proposed a different universal model. It assumed the universe was finite and contained a finite amount of stuff. It also assumed there was no infinite "smallness". This means that there would be a finite number of ways (ridiculously huge, but finite) that this "stuff" could be arranged. The "multiverse" model was that each and every one of these arrangements exists in a "freeze frame" or timeless "cell". All of these cells are arranged in a kind of honeycomb structure. Each cell being surrounded by every other cell representing every way the stuff in it could move in a single Planck Time. A person's conscious life is essentially a journey, a hopping from cell to cell in a straight line. But every consciousness in the universe follows a different line, meaning that every individual person experiences the universe in a unique way. It may seem that every one else shares your same reality, but in actual fact, no one else does. The issue (and the paradox) was down to two individuals, they are the same physical person, but two separate consciousnesses following different time lines. But at some point, those time lines intersect meaning two very different lives meet at the same point. All the history of each up to that point was totally different, but ultimately led to the exact same universal configuration. But this is the problem, since both of them now have the same arrangement of matter/energy, they cannot have different memories, as their brains would be exactly the same at that point.

  16. if you don't understand any of this, don't worry even the people who proposed this don't understand jack

  17. We can't travel and see through alternate universes because if somebody meets with his/her alternate universe counterpart then interact with him/her, they will collide and turn into a menger sponge then explode.

    Traveling through alternate universes can only be possible with my stand Filthy Acts At A Reasonable Price, it allows multiple universes/worlds to co-exist at the same time.

  18. Multiverse theory where its just separated by an enormous amount of space only out side of our observable universe isnt a parallel to me. I dnt think there can be an exact version of me if we are just outside of our observable universe which is still in the same universe to me.it might be identical at most but no way a parallel where we go thru the same events and circumstanced just played out different. That would still be another person just identical at most by any chance. A parallel to me imo would be somthing that is separated beyond physical realm. N the closest link we have to that that i can think of based on my understanding would be the human mind which is still yet not fully understood of its full capabilities .

  19. Maybe all the stories you read are actually happening in other parallel universes.

  20. I mean I'm pretty sure we can prove it by building up speed for 12 hours

  21. I Writing a Story (Fanfict) and this help me to explain about Universes

  22. In a parallel universe, absolutely nothing is different except for the fact a single blade of grass grew a centimeter to the left instead of a centimeter to the right or forward or backward, or diagnal. And then imagine all of those possibilities as 2 centimeters and so on. Every single thing has the potential to create an infinite number of universes.

  23. Is there a universe where this is true science and not philosophy?

  24. I don't believe this because it doesn't make much sense. if two universes are born from one universe that means they have exactly the same past. I believe the future and present are shaped by what happened in the past. if the two universes have exactly the same past 100%, that means the two universes will forever be the same unless if disturbed by an external force (a force from outside the universe). so the multiverse theory that says one universe… option A happens and in another universe… option B happens doesn't make much sense to me. they both have the same past. so if one universe goes with option A the other universe should also go with that same exact option because there's no reason for them to be different unless there's an external force. the multiverse theory I I like to imagine is the one that says they've been multiple universes since the beginning of this universe or before the universe. or the big bounce theory

  25. All this shit doesnt work without a spiritual component… .. . spiritual NOT religious… .. .

  26. What is the difference between a parallel universe, parallel dimension, and a parallel reality? Especially a parallel reality, what the heck is that about?

  27. I believe in the marvel Comic's perception of the multiverse and MCU's perception of time travel.

  28. My own dreams convinced me of this. Thanks for the explanation 🙏💜🕉

  29. So in another universe Optimus prime would still be protecting earth 😃😃

  30. If this is true it means my parents love someone else in another universe, not me😟😥

  31. Probability is simply a science that attempts to predict possible outcomes. That doesn't mean possible events will occur, there is just too many variables to make an absolutly accurate statistic. Any moment is the culmination of every cause an effect event with a very specific preset result. Parralel universes as a whole is just the result of fantastical speculation on rather unknown parts of our reality that we will probably never know existed.

  32. What if in the 9D theory there was some sort of hook that they had which let them travel through the multiverse and that's why ghosts and vampire and ancient gods are a thing

  33. Doesn't the many worlds interpretation defy the laws of conservation of energy? If every decision branch created both universes, then where did that energy come from to create the extra universe? And, since there have been quantum state collapses since the beginning of time, if each produced both possible conditions, wouldn't the amount of energy needed to create a new bubble universe for each quantum state collapse require energy that approaches infinite? The simplest answer is the collapse is a juncture that only produces a single outcome, not spawns an complete alternate bubble universe. It's also the one which changes energy state, neither creating nor destroying energy.

  34. If it was a parallel universe we wouldn't be there right?

  35. In a parallel universe the person we lookup to the most is us.And who knows, maybe this time they lookup to us!?

  36. an a press is an a press, you can't say it's a half

    i hope no one used this

  37. In a parallel universe, I graduated college at 2 years old. Thank you, thank you.

  38. If you want to get a different idea about the whole parallel universes thing make sure to watch My friend has been living in an alternate reality for 7 years

  39. I have a thunk for the bubble theory. A 2D object cannot stand up in a 3D world. A 1D object cannot stand up in a 2D world. So we cannot stand up in a 4D world?

  40. In an other universe tik tok doesnt exist. I want to be there

  41. Meanwhile in parallel universe, I am sleeping instead watching this at 3 o'clock in the morning

  42. So when I see a person I didn't see him before and I feel I know him may be I know him in parallel universe !

  43. So there's gotta be a parallel universe where My Chemical Romance hasn't broke up.

  44. Actually, for the brane-world model, it is possible that gravitation is able to interact through (all or some of) the other dimensions, which should lead to detectable gravitationnal effetcs that we could not attribut to any visible matter (since electromagnetic force is confined in our three dimensions). And … we actually measured those evidence for brane-world model (and call it "dark matter").

  45. GODDAMMIT VALENTINE

    In the alternate universe, jesus told the president to kill that fucking asshole crippled and his mozarella friend

  46. I think when things move randomly like chairs and stuff it happens for a reason it could be a psychic outside of this universe or god trying to save us from something bad happening to us

  47. I like to think there are universes based on fictional we made here, because there is an infinite amount of universes possible.
    So perhaps the Avengers do exist but we just can't interact

  48. If The Universe expands, And The Magnetic poles Shift, You stand at One Point and as the world Turns and evolves around the Sun, and the Universe Expands, You would Be at Another point in space and Time, if You was Frozen in that spot.

  49. Oh Dead Ion Now Right, Well what do you see, but a Monkie, and The New Elon musk Company.

  50. I'll call the Komodo Dragon, If You Dy Tell Them They Are Welcome To Be Gay, All day, Cause it's the Happy happy joy joy Song, Monkie

  51. If the many worlds theory is true, then there is a
    World that it isnt….

  52. Now im sad i live now and not at a time scientists have figured this out… If they ever Will tho

  53. So, is it possible that a man made story become a whole new universe?

  54. The repetitive "there is no experimental evidence" is so stupid. That's why it's called theoretical physics!

  55. I call the multi-multiverse or how I see it the 9th dimension the The dimultiverse, or bimultiverse.

Leave a Reply

Your email address will not be published. Required fields are marked *