There Is No "You" In a Parallel Universe

StartsWithABang (3485481) writes "Ever since quantum mechanics first came along, we've recognized how tenuous our perception of reality is, and how — in many ways — what we perceive is just a very small subset of what's going on at the quantum level in our Universe. Then, along came cosmic inflation, teaching us that our observable Universe is just a tiny, tiny fraction of the matter-and-radiation filled space out there, with possibilities including Universes with different fundamental laws and constants, differing quantum outcomes existing in disconnected regions of space, and even the fantastic one of parallel Universes and alternate versions of you and me. But is that last one really admissible? The best modern evidence teaches us that even with all the Universes that inflation creates, it's still a finite number, and an insufficiently large number to contain all the possibilities that a 13.8 billion year old Universe with 10^90 particles admits."

Comments

Except inflation

[Anonymous Coward]

has nothing to do with "parallel" universes...

Re:Except inflation

[tysonedwards]

Except, it does... Inflation dictates the spatial dimensions occupied by the observable universe and distribution of matter within it. If said inflation occurred differently even in what could be described as the most insignificant value, than matter distribution could be dramatically different than what we see today in our observable universe. Different matter distributions == a universe in which said parallel universe which is inherently different than what we see around us.

However, at the same point it may as well be saying that within the multiverse where an infinite number of other universes exist, it is more plausible that there will be universes that are not like our own than there are those that are like our own as fundamental laws regarding the creation of said universes need not be identical, preventing the creation of sufficiently similar natural systems; ergo, the Goldilocks Principle.

Re:Except inflation

[binarylarry]

I wonder what mirror universe Jesus would be like.

Shaven, well manicured, free market capitalist homosexual libertarian??

Re:Except inflation

[ArmoredDragon]

No, I think Jesus in the mirror universe would be white instead of middle eastern.

Re:Except inflation

[networkzombie]

Your geek card has hereby been revocked.

Re:Except inflation

[Immerman]

> Yet even if they approach an infinite amount of space between each there will remain an gravitational attraction between all particles that will bring them back together given enough time, and will return to the original configuration before the explosion.

Not so. According to the currently widely accepted interpretation of Hubble observations the universe is not only expanding, but expanding at an ever-accelerating rate thanks to the influence of so-called dark energy. Under the influence of that effect - generally interpreted to be an expansion of the fabric of spacetime itself, the entire universe will expand exponentially long after the average density of both normal and dark matter is so close to zero as to make no difference, and the incredibly diffuse dark energy is effectively all that remains. The universe is destined to end not in a "big crunch", but as an eternally cold and empty void, with even the individual protons shed by long dead stars separated by such vast distances that they are no longer causally connected.

Parallel

[Livius]

Those universes aren't what people usually mean by 'parallel'. Usually they're thinking of a universe which at some point in the past was identical to this one.

These orthogonal universes obviously aren't going to have duplicates of anything here.

Re:Parallel

[Immerman]

Nothing obvious about it. Presuming inflationary theory is correct, there will be a nigh-infinite number of other "bubbleverses" spawned within the perpetually expanding inflationary energy. Now, since in that model our own "bubbleverse" is finite, then if the the number of other bubbleverses was truly infinite then all possible bubbleverses would exist, including an infinite number of exact duplicates of our own (and every other) bubbleverse. However, if we instead presume that the inflationary energy is *not* infinite, then you must compare the number of potential bubbleverses with the same physical laws as our own to the number of potential states that such a bubbleverse could be in. If there are sufficiently more bubbleverses like our own then there are states in which our bubbleverse can be in, then by the pigeonhole principle there must by necessity be some bubbleverses that are near-perfect duplicates of our own - including being home to some "other you".

As I understand it, current theory and observation suggests that the inflationary period began *after* the birth of the universe (multiverse?) 13.8 billion years ago, so that puts a hard upper limit on how much inflationary energy can exist in the "multiverse", and thus how many "bubbleverses" like ours could have been spawned within it. Presumably they did the calculations and determined that the number of possible bubbleverses like our own is radically less than the number of possible states our bubbleverse could be in, thus establishing that it is very unlikely that any near-duplicate universes exist.

At least within that definition of parallel universe. There is of course also the many-worlds interpretation of quantum mechanics, as well as brane theory and it's ilk, which postulate two additional, and entirely different, kinds of parallel universe which may *also* exist. And the Many Worlds Interpretation at least would absolutely suggest the existence of a large number of near-identical universes - after all Schroedinger's poor cat would have to be discovered both alive and dead by alternate Schroedingers who didn't bifurcate until the experiment was performed.

(As an interesting side consideration - would you get an alternate Schroedinger for every instant in which the istotope either did or did not decay? Or would the alternates consolidate as the particular instant of decay ceased to be relevant to the timeline?)

Re:Parallel

[Immerman]

A very limited definition of parallel. Parallel lines will never intersect, but that only implies a constant distance and identical heading when dealing with Euclidean space. Take a course in non-Euclidean geometry sometime and you'll discover far more bizarre forms of parallelism.

This is junk science

[TrollstonButterbeans]

And the support for Big Bang style cosmic inflation (universe ballooning up from nothing in a trillionth of second) is sparse. (As opposed to the normal expanding universe we see that even old Steady State theory said existed.)

If cosmic inflation happened, everything real far away should be in its infancy, but we see sprial galaxies 13 billion years away.

Quasars are supposed to only be in the beginning of the universe in early times according to the Big Bang, and there are 2 of them within 800 million miles of us which should not even be possible. http://www.sdss.org/news/relea...

So we have old structures very far away well-developed with plenty of metal, which shouldn't happen.

We have "newer" structures nearby, which shouldn't happen.

Add to the fact there are no metal-free stars (Pop III) ever seen, it is difficult to see what aspect of Big Bang Theory holds true. Astronomy might be better off if it were discarded because a number of the popular conclusions double-down on bad science and result in wild goose chases (dark energy only need exist to support the Big Bang because only the Big Bang says expansion must be accelerating.)

Re:Damn!!!

[Anonymous Coward]

There goes my alternates chance with Kate Upton.

FYI: There's a theorem called the Universal Invariance of Supermodel Fornication in Closed Kleene-Star Domains which shows that with high probability, unless you've had sex with one in this universe the sum over all universes of the probability of you ever having sex with a supermodel is precisely zero.

Laymen refer to the theorem by its acronym: UISFCK*D.

hmmmm

[bloodhawk]

So now we are making predictions about speculations and guesses to say, there is no you in a parallel universe. Call me a skeptic but I would like a molecule of proof that such universes even exist before you start on speculations about what exists in them.

Looks like a very long straw man

[Crashmarik]

Not saying that the parallel universe concept is correct but his argument just dismisses a particular type then states there aren't any.

Re:Prove it!

[Tablizer]

Show me one other alternate universe.

Fox "News".

Define parallel universe

[Immerman]

Well, it kind of does, depending on exactly how you define the term. One of the implications of inflation theory is that the original superluminal inflation is still going on, and will always be going on, and what we consider to be "the universe" is but one tiny bubble of "stabilized" space that decayed from the inflationary energy, and is presumably surrounded by a nigh-infinite number of other bubbles with different physical laws that will never interact with each other because the space between them is still full of self-replicating inflationary energy expanding faster than light, and which is perpetually spawning still more bubbles as the false-vacuum spontaneously decays into lower-energy states to trigger a chain reaction. You could easily consider every one of those other "bubbleverses" to be a parallel universe, with it's own physical laws and causality that will never intersect our own.

Of course that has absolutely nothing to do with the sort of parallel universes posited by the many worlds interpretation of quantum mechanics, which absolutely would spawn a potential infinitude of "other yous" with every quantum "decision". And neither has anything to do with the third major posited type of parallel universe which stipulates that our universe is a 4-dimensional membrane existing in within the 11+ dimensional metaverse posited by many QM theories, and that other membranes likely also exist, and may occasionally collide with our own, causing "big bangs" from the release of energy on impact.

Any one of those, or even all three, might exist, but so far as I know only the first is a necessary implication of currently accepted cosmological theory, and thus it has sort of inherited the "parallel universe" crown.

Re:Define parallel universe

[pspahn]

Mr. Nobody.

It's a great film. All those pointless decisions that get made that shape the things around us and, in turn, the world for ever. Just imagine, had that nomadic hunter-gatherer ancestor of yours decided to head back out to hunt rather than go home, you, and everyone in your lineage, would fail to exist.

In that moment when that ancestor was deciding which way to go, everything was possible.

But what about anti-You?

[Megahard]

Remember, if you meet anti-You, just bow, not shake hands.

...which is therefore not parallel

[Roger W Moore]

Different matter distributions == a universe in which said parallel universe which is inherently different than what we see around us.

I think there is some confusion over what "parallel" universe means. This is generally taken to be a universe which has been an exact parallel of our own universe up to some point after which it diverges i.e. everything is the same up to some point in time. In the quantum multiverse interpretation of QM this happens for each possible result of collapsing the wave function.

I've never heard of this ever being associated with multiple 'universes' from inflation because QM requires that the universes interact before they separate (this is how it explains the self interference of a single particle) whereas inflation requires that the universes be causally disconnected after their creation i.e. inflationary universes are just different universes, not parallel ones. So I think the author of the article got himself rather confused.

Re: ...which is therefore not parallel

[tysonedwards]

Agreed, and it is an unusual concept to mull over hence the article. The vernacular used is theirs, throwing out that the multiverse isn't composed of mostly identical copies of our universe spawned via wave function collapses, or in another incarnation completely separate universes that are identical until a wave function collapse at which point there is a divergence, or any number of similar theories. It is a fascinating concept, and in and of itself does not preclude the possibilities of conventional "parallel" / "mirror" universes, it simply implies that out of any like universe, there may be trillions that are completely unlike ours in every sense of the word.

Re:As Usual

[Immerman]

Even if an infinite number of universes exist, that does not imply that any of them are remotely similar to ours. For that implication to hold you must also assume that our universe is finite, or at least a drastically lower order of infinite such that the total number of possible states that our universe could be in is substantially less than the total number of universes that exist with the same geometry and physical laws.

Of course meaningfully comparing different orders of infinity isn't something you can do with high-school arithmetic, but it's a pretty common thing to do in advanced mathematics.