One universe or many? Panel holds unusual debate

World Science ^ | March 30,. 2006

[D-fendr]

They're speaking of completely separate universes lying outside the inflationary bubble that we inhabit.

Then, if true, our universe consists of more than one inflationary bubble. Uni means one. Whatever exists is part of our universe.

The rest sounds like semantics, yes?

[timer]

The truth is always simple, although unpalatable to many a flim-flam man... Can you demonstrate infinity? Typical example : slice up a watermelon into an infinite number of pieces by cutting off zero pieces...how much air do you want to wear out... until the world wears flat or hell glaciates? Can you think of any other examples? Thus n/0=n-0-0-...=n because division is repetitive subtraction and nx0=n+0=n because multiplication is repetitive addition in a magnitude sense(rotate the symbols 45 degrees : / to - and x to +). Agree or disagree?

[jennyp]

IMO, here's why the Anthropic Principle will never fly:

But then Linde thought of another channel of communication between creator and creation—the only one possible, as far as he could tell. The creator, by manipulating the cosmic seed in the right way, has the power to ordain certain physical parameters of the universe he ushers into being. So says the theory. He can determine, for example, what the numerical ratio of the electron's mass to the proton's will be. Such ratios, called constants of nature, look like arbitrary numbers to us: There is no obvious reason they should take one value rather than another. (Why, for instance, is the strength of gravity in our universe determined by a number with the digits 6673?) But the creator, by fixing certain values for these dozens of constants, could write a subtle message into the very structure of the universe. And, as Linde hastened to point out, such a message would be legible only to physicists.

All these ratios between the fundamental forces would either be uninteresting-looking on their own, or they'd look ironic in some way. If they look ironic to us, then we'd just take that as a cue that they must be causally related in some way to some more-fundamental force, instead of actually being "arbitrary".

But there's no reason why this fundamental relationship has to be a designed relationship. For example, if the relationship of force α to force β is π, what would that imply to us? That there's a Designer who is fascinated by the ratio of the circumference to the diameter? Or that the β force really does represent a circumference of something and the α really does represent that something's diameter? The fact that there's some ratio that happens to look interesting, by itself gives us NO clue.

And so the physicist will pursue the hypothesis that the interesting ratio is a clue to a shared (natural) causality, and the spiritualist will write a popular book claiming pursue the hypothesis that the interesting ratio is a clue to the Designer's psychology. <shrug>

Nope, I say that any Designer would have to understand the particular language that the inhabitants of His universe write, and imprint a message in that language. So I think that pretty much rules out our being able to detect such a God if He was a physicist-in-a-lab-type.

[jennyp]

There is no obvious reason they should take one value rather than another. (Why, for instance, is the strength of gravity in our universe determined by a number with the digits 6673?)

A. That's the physicist's PIN number for his debit card.

[snarks_when_bored]

There are several ways of talking about this. I kind of like cosmic bubbles (or Guth's pocket universes). Linde speaks of thermalized regions. The general idea seems to be that we inhabit a single inflating region within a much vaster (perhaps infinite) realm filled with (perhaps infinitely many) inflating regions and also (perhaps infinitely many) regions that aren't yet inflating. Each inflating region has its own set of fundamental physical constants, and, depending on the values of those constants, life-forms of one sort or another may or may not be possible therein.

It's a grand vision. But is it true? We don't know yet, and maybe we'll never know. In physics, there are no guarantees of access to evidence.

[edsheppa]

Everett's branching quantum universes are completely separate and have no physical contact of any kind

Depends on what you mean by "physical contact." Some folks see quantum interference as an interaction between these different universes.

Also, about the branching. Another conceptualization of the multiverse, analogous to certain conceptions of spacetime, is a fully elaborated "static" multiverse. For any event that occurs in N universes and can have two outcomes with probabilities p and 1-p, pN of them have one outcome and (1-p)N have the other.

[LibWhacker]

“The multiverse is like a bubble bath,”

Don't like the analogy. Bubbles burst.

[edsheppa]

Is there any use thinking about a parallel universe which can never be reached from ours?

Yes, it is conceivably useful. For example, a theory built around this concept might make certain calculations easier or make certain outcomes easier to intuit.

If the scientists do succeed in creating a universe in a laboratory, are they not doing what the God of this universe did in Genesis/the Big Bang?

Have you read the book Cosm? I recommend it. It reflects badly on me I know, but the religious questions raised didn't occur to me until the kidnapping episode quite a ways into the book.

BTW, I'm certain you actually meant "thought by some to have done."

[snarks_when_bored]

Depends on what you mean by "physical contact." Some folks see quantum interference as an interaction between these different universes.

I had in mind interactions via one or more of the four fundamentals, but, you're right, one mustn't forget about the quantum jitters.

Also, about the branching. Another conceptualization of the multiverse, analogous to certain conceptions of spacetime, is a fully elaborated "static" multiverse. For any event that occurs in N universes and can have two outcomes with probabilities p and 1-p, pN of them have one outcome and (1-p)N have the other.

The "it's in there!" view of reality.

[edsheppa]

I see we have a naive First-Causationist among us. I'm curious how you cling to that view. Why do you think it's more likely than the many modern speculations that don't require it?

Also, it seems to me that these scientists are begging no question, just pushing the frontiers of science thinking up crazy sounding stuff to see if it works.

[Lancey Howard]

I think a more interesting subject is the subject of seperate realities.
I wonder if the panel distinguishes the two?

[D-fendr]

(perhaps infinite) realm filled with (perhaps infinitely many)

Isn't infinite an abstract mathematical term? Is there anything in physics that is actually infinite? Other than theoretically. And by theoretically I mean such as mass at the speed of light - not existing in reality.

Infinite gives you sufficient "probability resources' to go anywhere you wish with any possible theoretic supposition.

But isn't this essentially a cosmic punt scientifically?

thanks very much for your reply...

[TN4Liberty]

That would be precisely one yottameter.

Sounds like the name of a hamburger.

[Caipirabob]

Yer wastin' yer time sweetie, he's as queer as a 3 dollar bill...

Mmmmm...Uhura! *slurp!*

[Erasmus]

Would the bozos of that universe worship us a gods? Would they fight Holy Wars over balrog666 vs snarks_when_bored?

If you saw MIB II ("MIIB") you might recall the storage locker scene in the airport (train, bus?) terminal.

[Erasmus]

Gregory Benford wrote about a universe-in-a-bottle created in a hadron collider in his novel Cosm.

[UnbelievingScumOnTheOtherSide]

apochriphal => apochryphal => apocryphal => http://www.m-w.com/dictionary/apocryphal

[RHINO369]

Schroedingers Cat Paradox How can something be alive and dead at the same time? Some think a whole new universe is created. Read bout the most famous cat in Physics history

[UnbelievingScumOnTheOtherSide]

Say it ain't so!

[UnbelievingScumOnTheOtherSide]

Say it ain't so!