How Does Multiverse Theory Make *Every* Universe Possible?

Is every combination possible based off of uncertainty? When the big bang happens in another universe and one electron moves slightly differently because of uncertainty it changes everything. Is that why there are "infinite" number of universes?

When people say infinite do they really mean infinite? So is it actually true (if I were in another universe) that everything could be the exact same, but instead I'd be writing the answer to this question just because I figured it out before anyone else on the world or does that have implications that would make the multiverse different in different ways?

It is not known whether there are an infinite number of universes.

In theory, however, it is often said that in an infinite multiverse, all possible realities play out. It's fun to imagine, say, two different universes with identical histories up until a particular point, when you suddenly decide to do something different in one of the universes. I think this is what you're getting at when you say "be the exact same". This is actually not possible if determinism holds. Sure, quantum uncertainty allows for identical pasts to have different futures, but there are limits: an electron might jump an energy level in one universe and not the other, but a human being won't suddenly decide to act differently because such macroscopic activities require a great number of quantum mechanical events over a relatively long time scale.

I would argue that macroscopic events can be changed across the entire universe by even the influence of the gravity of the electron jumping a tiiiiny bit further due to chaos theory.

What does chaos theory have to do with quantum transitions?

Not my scope of knowledge but I'd like to throw this in:

I read a book on bubble theory, the theory that the there are a number of universes, surrounded by an event horizon out of which no universe can observe the others.

Anyway, the author made a case for the differences in the universes occurring from variations of the fundamental forces after they separate. For example, in one universe, an instant after the big bang, matter and energy become distinct. An instant later, gravity, strong and weak nuclear force, and EM force become distinct. However in this universe, gravity is a fraction weaker than in ours, and so, theoretically, dust clouds never clump into planets or stars.

Yes, that kind of multiverse is particularly motivated by string theory (the so-called "landscape" of string vaccua) where each universe has different values of the fundamental constants. The string landscape, though embarrassingly vast, is not infinite.

bapowell said:

What does chaos theory have to do with quantum transitions?

bapowell said:

Yes, that kind of multiverse is particularly motivated by string theory (the so-called "landscape" of string vaccua) where each universe has different values of the fundamental constants. The string landscape, though embarrassingly vast, is not infinite.

Any tiny movement in one area affects the entire universe. One electron moving a tiny bit differently changes everything in the universe. (wiki: "studies the behavior of dynamical systems that are highly sensitive to initial conditions")

noname2020x said:

Any tiny movement in one area affects the entire universe. One electron moving a tiny bit differently changes everything in the universe. (wiki: "studies the behavior of dynamical systems that are highly sensitive to initial conditions")

Sure, but that's not the same thing as having two identical universes up to a particular point at which something suddenly occurs on a macroscopic scale in one and not the other. Quantum physics will cause macroscopic differences, but these will take time to manifest.

bapowell said:

Sure, but that's not the same thing as having two identical universes up to a particular point at which something suddenly occurs on a macroscopic scale in one and not the other. Quantum physics will cause macroscopic differences, but these will take time to manifest.

I didn't say it wouldn't take time to manifest. Basically, my question is: Does multiverse theory claim that there are literally an infinite number of universes where I am a doctor in one that cures cancer and I'm a MMA fighter in another? Any wouldn't this mean there are a huge number of degrees of infinity?

Multiverse theories are highly speculative at this time (there is no "multiverse theory"), and so we have no idea what the physics of the multiverse is. If you wish to postulate that there are infinite number of universes, each with different initial conditions (different positions and momenta of all the particles) then, yes, there will be a universe where you cure cancer and one where you are an MMA fighter providing that neither of these is physically impossible.

In some multiverse theory there is infinite possibilities with different physical properties.

Weird for me as an atheist to accept. There could be a universe in which a God created everything in six days a few thousand years ago. As a paleontologist I'm am writing about it in that Universe with derision because it all seems silly... however, in an infinite number of universes there could be...

Yikes...gets too weird.

Yes indeed, it does seem silly.

I certainly won't be subscribing to any multiverse theories until someone puts some hard facts on the table. That doesn't seem likely with multiverse theory any time soon.

the quantum mutiverse is an interpretation of Quantum Mechanics, and as an interpretation it doesn't touch the physics of it (I know quantum mechanics in some good extend but I don't really care about the "multiverses") but it's a philosophical point of view. You can do quantum mechanics without getting involved in the different interpretations of it.

The multiverse in string theory is a different thing, and it doesn't apply to different moments or "measurements". I think it was applied at the beginning of the Universe when it was supposed to be a "stringy"-theory governed thing. In strings (if someone believes that this is a real physical theory- I don't) I think you can derive the number of those extra universes that were 'born' together with ours (so it's a "prediction" -bad I'd say- and not an "interpretation")...and that's why to people who tell me that sting theory predicted our Universe, I return that it predicted it together with a vast number of different ones...if I recall well some people found ~10⁵⁰⁰ ones, together with ours.

I say to those who tell us that string theory predicted our universe:

No, because your models have 11 dimensions, whereas our universe only has 3.

NIgelSmith50 said:

I say to those who tell us that string theory predicted our universe:

No, because your models have 11 dimensions, whereas our universe only has 3.

There's more to it than that. String theory predicts that extra dimensions are compactified, making them difficult to observe directly.

I know what it predicts and I know that the extra dimensions are 'compactified'.

As I said, it is wrong because our universe has 3 dimensions.

NIgelSmith50 said:

I know what it predicts and I know that the extra dimensions are 'compactified'.

As I said, it is wrong because our universe has 3 dimensions.

That's not a valid argument in physics.
I too try to remain sceptic but don't start criticizing for the sake of criticizing.

If you must point out flaws start with the absence of deSitter solutions.

Also we live in a universe with 3 spatial dimensions. Not 3 dimensions altogether, 4 dimensions is what we work with since Einstein's GR.

bapowell is correct (within the scope of string theory), the predicted size of these compactified (curled up) dimensions is (can be?) smaller than scales we can probe at this time.

NIgelSmith50 said:

I know what it predicts and I know that the extra dimensions are 'compactified'.

As I said, it is wrong because our universe has 3 dimensions.

How do you know that our universe has 3 dimensions?

Every time I hear this 'curled up dimensions' I cringe. Show me evidence for this please.

I know the universe has 3 dimensions because I exist in it.

NIgelSmith50 said:

Every time I hear this 'curled up dimensions' I cringe. Show me evidence for this please.

I know the universe has 3 dimensions because I exist in it.

We don't have proof, we don't have prove against it either.
Within the confines of science this means we cannot dismiss the theory as false!

We keep with the theory because various reasons (this is my feeling about this).
One will be senior scientists don't want to abandon a theory they spent a significant part of their life on.
Another is the elegance of the theory (the idea is quite simple, the maths gets hard quite soon).

The extra dimensions are there for technical reasons and really make our starting point simple. (for example 11D sugra contains a graviton, gravitino and a 3-form gauge field, not that much particles).
The technical reasons are easy to see in modern books (I liked the treatment in Becker, Becker, Schwarz for bosonic strings).

But as you say, we only perceive 3+1 dimensions so we have a surplus of dimensions.

We don't have proof against it?? Whatever happened to the scientific method?

I was asked how I know the universe has 3 dimensions like this was in any doubt. I don't accept the '3+1 dimensions'. The +1 dimension you refer to is not in any way equivalent to a spatial dimension.

NIgelSmith50 said:

Every time I hear this 'curled up dimensions' I cringe. Show me evidence for this please.

I know the universe has 3 dimensions because I exist in it.

There is no evidence for "curled up" dimensions. They are simply a characteristic prediction of the theory. Atoms were speculated about millenia before they were observed: it would have been foolish to discard such ideas simply because no atoms were seen in ancient Greece.

You exist in the universe and interact with it via the fundamental forces. Hence your experience depends on their character. You take it for granted that these forces probe all of spacetime in such a way that humans can perceive all that there is.

NIgelSmith50 said:

We don't have proof against it?? Whatever happened to the scientific method?

What proof do we have against extra dimensions existing at the Planck scale?

JorisL said:

Within the confines of science this means we cannot dismiss the theory as false!

You can dismiss it as "unscientific" ... by no means can string theory be considered a scientific theory in the common sense...
Up to now it's a department of mathematics, with a few attempts by some phenomenologists to give it some predictability (without success).

ChrisVer said:

You can dismiss it as "unscientific" ... by no means can string theory be considered a scientific theory in the common sense...
Up to now it's a department of mathematics, with a few attempts by some phenomenologists to give it some predictability (without success).

Let's not get hung up on semantics. The question of whether or not the universe has more than 3 spatial dimensions is absolutely an empirical one. Whether string theory is "scientific" or not has nothing to do with it.

bapowell said:

Let's not get hung up on semantics. The question of whether or not the universe has more than 3 spatial dimensions is absolutely an empirical one. Whether string theory is "scientific" or not has nothing to do with it.

What do you mean by empirical? The extra dimensions is not a problem since the theory can explain why we don't see them... The problem is the theory and whether it can give real answers for the Universe we live in.

ChrisVer said:

What do you mean by empirical? The extra dimensions is not a problem since the theory can explain why we don't see them... The problem is the theory and whether it can give real answers for the Universe we live in.

From Oxford:

Emprical: Based on, concerned with, or http://www.oxforddictionaries.com/us/definition/american_english/verify#verify__2 by http://www.oxforddictionaries.com/us/definition/american_english/observation#observation__2 or experience rather than theory or http://www.oxforddictionaries.com/us/definition/american_english/pure#pure__2 http://www.oxforddictionaries.com/us/definition/american_english/logic#logic__2 .

Your comment was in response to JorisL's statement that a lack of evidence for extra dimensions is not evidence for the lack thereof. He is correct, and I'm saying that extra dimensions, as physical properties, are in principle measurable. What's "unscientific" about that?

Unscientific is the theory which cannot be falsified/verified by some experiment.
The whole statement of JorisL was:

We don't have proof, we don't have prove against it either.
Within the confines of science this means we cannot dismiss the theory as false!

I am saying that in the 1st line, the theory becomes unscientific. How can you then speak about the confines of science over it?

ChrisVer said:

Unscientific is the theory which cannot be falsified/verified by some experiment.
The whole statement of JorisL was:I am saying that in the 1st line, the theory becomes unscientific. How can you then speak about the confines of science over it?

Why can't the existence of extra dimensions be falsified?

bapowell said:

Why can't the existence of extra dimensions be falsified?

tell me an experiment that we should conduct to check for it...or sole predictions it can give so that we can indirectly check it...

3+1 works perfectly well at macroworld-- pointer. On the other hand, quantum realm begs for multiplicity(universes/manyworlds and stuff) due to weird observables -- superposition. Somehow we don't have any success in making it classical (consistency issues with experiments). So we are forced to use probability and wavefunction evidently works pretty well. In consequence, a particle that could go up or down — all of the possibilities happen in "different worlds". These "different worlds" are in fact different parts of the same universal wave function, but for all intents and purposes their futures are entirely separate; the only way they could come to interact again is if both of them lead to situations that are completely indistinguishable on the particle level, in which case they would "interfere" constructively or destructively, making such an outcome more or less likely. MWI is an interpretative crossroad between science/unscientific and multiverse is way beyond that. I just stick to Meh..for now ^^. BTW what is cutoff?

ChrisVer said:

tell me an experiment that we should conduct to check for it...or sole predictions it can give so that we can indirectly check it...

Missing energy in a collider.

Yes, I grant that at present we are woefully under the appropriate energy threshold to rigorously test this prediction. But that is not the point of this thread, which is in response to Nigel's comment that the absence of evidence for extra dimensions proves their absence. This is false, regardless of the feasibility of the experiment.

ChrisVer said:

tell me an experiment that we should conduct to check for it...or sole predictions it can give so that we can indirectly check it...

Sir, you seem very unrealistically negative about the entire possibility of a multiverse. Just because there is not science to prove or disprove something does not negate it's potential existence. If you are so inclined to NOT believe in the possible future discoveries then just simply look to the past and give a thought to the potential future. At one point "the major scientific discoveries" of the world included first thinking the Earth was flat, then round, then they found planets and discovered the sun and all it's bodies orbited the earth...to think otherwise could possibly land you in prison or even executed...well we know the truth is planets orbits the sun...
Taking that into account at some point they thought only one sun, one solar system, one galaxy, etc...but come to find out there are trillions upon trillions of each.
In fact through out all of creation and existence itself there seems to be at least pairs of things all the way down to many of the very building blocks of matter itself. On top of that it seems existence itself is cyclical, things are born and things die, the remnants either create new similar life, a different life or both. It stands to reason then that this single universe that we are fixated on only needs a little more time, technology and science to prove there is actually more than one. I can actually envision trillions upon trillions of universes all being born, living and dying in this natural process of physical existence and our universe in all it's enormity is only a single thing that will also one day pass away and bring about a new and different universe in it's wake. This may also give more credence to the big bang theory by supplying a location of the bang before it 'banged'. Maybe the death of a previous universe was the bang that created this one...maybe two universes collided to make the bang. So much to be discovered yet that we shouldn't close our minds to ever...
so my request to you is ...Give me science/theory or opinion that can prove or disprove the above. The important thing here is to never stop questioning right?

noname2020x said:

Is every combination possible based off of uncertainty? When the big bang happens in another universe and one electron moves slightly differently because of uncertainty it changes everything. Is that why there are "infinite" number of universes?

When people say infinite do they really mean infinite? So is it actually true (if I were in another universe) that everything could be the exact same, but instead I'd be writing the answer to this question just because I figured it out before anyone else on the world or does that have implications that would make the multiverse different in different ways?

There is an argument that infinite universes is the simplest. Alternatively, there should be a reason for whatever the finite number might be, whereas infinity needs no reason.

I'll leave you guys to argue where the burden of proof should lie.

C.E. said:

Sir, you seem very unrealistically negative about the entire possibility of a multiverse.

I am. I am unrealistically negative to un-realism . Since that question touches the matter of "belief" and is untestable, it's viable for me to believe whatever I like. And the multiverse theories are so well untestable built, that they give me this freedom...so it's not me who has the problem with being "suspicious", it's the theory's problem that allows for such suspicion to rise.

C.E. said:

Just because there is not science to prove or disprove something does not negate it's potential existence.

Just because there is no science to prove or disprove it, it is unscientific. As a philosophy would be.
and by no means I want to say that being non-scientific is bad (maths is not bad), it's just a state.

C.E. said:

f you are so inclined to NOT believe in the possible future discoveries then just simply look to the past and give a thought to the potential future. At one point "the major scientific discoveries" of the world included first thinking the Earth was flat, then round, then they found planets and discovered the sun and all it's bodies orbited the earth...to think otherwise could possibly land you in prison or even executed...well we know the truth is planets orbits the sun...
Taking that into account at some point they thought only one sun, one solar system, one galaxy, etc...but come to find out there are trillions upon trillions of each.

The fact that we only learn the theories that successfully described the world, doesn't mean that theories are a priori correct. In fact even when you pick up one theory by proving it experimentally, all the rest that were invented to give answers to the same questions are pushed back. So you can say that for one theory to be right, one or more were wrong/unrealistic.
How are the stars an indication that a multiverse exists?

C.E. said:

In fact through out all of creation and existence itself there seems to be at least pairs of things all the way down to many of the very building blocks of matter itself. On top of that it seems existence itself is cyclical, things are born and things die, the remnants either create new similar life, a different life or both. It stands to reason then that this single universe that we are fixated on only needs a little more time, technology and science to prove there is actually more than one. I can actually envision trillions upon trillions of universes all being born, living and dying in this natural process of physical existence and our universe in all it's enormity is only a single thing that will also one day pass away and bring about a new and different universe in it's wake. This may also give more credence to the big bang theory by supplying a location of the bang before it 'banged'. Maybe the death of a previous universe was the bang that created this one...maybe two universes collided to make the bang. So much to be discovered yet that we shouldn't close our minds to ever...

Of course I cannot prove/disprove that statement, as it's philosophical and not scientific. I could only accept/deny it. Also in order to avoid a philosophical discussion (at least in a thread- if you want PM me), it's better to leave it at this: I personally deny it..
For me questions make sense if I can find someway to prove them right or wrong. A multiverse cannot be proven because you can't actually go to some other universe (as long as you are not 'high') and/or work with it. If the question by itself lacks this feature, I consider it "something else". Maybe it's fun for some coffee break discussion, or after a Star Wars movie, or working with it in a pure mathematical way, but it's not a scientific question...