A Brief History of the Multi-universe

multiverse
I was working on a research project on the concept of the multiverse and while I enjoyed the incoherent rambling argument on whether there is a god or not Im feeling kind of empty. The universe is the way it is because if it werent then we wouldnt be able to contemplate on whether therte is a god or not. And trying to justify the existence of god through anything dealing with relativity is laughable. God is only able to exist through faith. And faith goes against everything that science stands for.

skinywhtboy
skinywhtboy, welcome to A2K, glad to have you here.

If God didn't exist, we would have to invent someone to praise and to blame. I guess that's what we did.

BBB

Re: multiverse


I'm not so sure about that. String theory fails to provide a testable prediction yet there are many in science who accept it and therefore is an exercise in faith. I guess the question is, are we talking physics or philosophy?

string theory=cats cradle

Isn't Multi-universe an oxymoron? Since Multi means many and uni means one. Unless you're suggesting that all of the universes somehow converge to make one big one.

Re: multiverse

At the very least, the results of the string theory equations are compared to what has already been measured about the universe, ane judged based on the degree of agreement. If you are alleging that nothing from the string theory equations was ever both measurable and not previously known, please cite your source.

A key issue in disscussion of "life" and "universes" is what constitutes "structure" or "order". For example, to take BGW's (and Capra's) fractal model of embedded "structures" we are still left with the regression problem of "who observes/defines such structure".

My own conclusion is that terms like "multiverse" have no separate reality with respect to a singular concept whilst the criteria for "reality" concern explanation of what we call "events" in the single universe. I am saying that the occurence of "life" is not an "event" in the usual sense because events presuppose "observers" who classify them as such. (Observation in "our minds eye" is cognitive sleight of hand) Note also the term "multi" implies "one who classifies or counts" and we can ask again who is this other than ourselves ?

In short, the corollary the universe appears like it is because we are like we are is equally valid.

The transcendent question is of course "what constitutes explanation" and how can this encompass the interaction of observer and observed ?

im back


String theory is an amazing concept to have been uncovered. It gives a bridge between quantum mechanics and everything above. But you kind of put words in my mouth. When i say faith i mean in an idea of religion. Someone who is willing to strap a bomb to their chest and blow up a coffee shop just for their beliefs. Whats better about string "theory" is that its an idea and it can be changed. If someone disproves it today scientists will think of a new one. But imagine you walk into the Vatican and say you want to change the bible, "jesus is black" (Dogma), you might get lynched.

Rather than take a reductionist view proposing infinite, slightly different universes that somehow interact (alah M-Theory), allow for strong emergence via the Landauer-Lloyd analysis of flaws in the of the Laplace's demon argument that supports reductionists. Basically this states the final outcome of a system may not be soley defined by outcomes written into the basic laws of physics * a gazzillion atoms, but there can be "a cosmic imperative" written into the laws of nature (Paul Davies - Macquarie Uni - Sydney, Australia - Emergent biological principles and the computational resources of the universe, Complexity vol 10(2), p1"

So basically ultra complex systems can produce wierd outcomes; such as rocks, intelligent life or high temperature superconductors all from the same raw materials - simply arranged slightly differentally. This might bring down the number of universes required to create life from infinite to merely fairly large!

Re: multiverse


String theory equations are appealing but stop short of actual substantiation. String theory can't be tested in the way that normal theories are tested. My point is that to say "faith goes against everything science stands for" is misleading, at least in this case.

Hey everbody, I just saw this conversation, and thought it was interesting, so I've decided to put in my two cents worth.

Basically, through all this conversation, it seems we've come up with this conclusion: as far as how we and/or the universe came into existence, scientists don't honestly have any honest to goodness answers and, more or less, make up answers to entertain their minds. However, basically all their theories, again more or less, fall very short of solving anything, and perhaps, even, pose even more questions.

Most of the answers quite simply sound like a wild guess, hold little to no credit, and... well, seem rather pathetic. lol

Here is a article on the subject I posted on another thread that most on this thread may have not seen. It is about the best I've been able to find that gives good information that can mostly be understood without a detailed knowledge of physics.

http://cosmos.asu.edu/publications/papers/MultiverseCosmologicalModels%2083.pdf

Also three things to consider:

Universe is simply an abstract concept man created which we are free to redefine it if it does not continue to fit our needs.

In the current standard theory there are already objects that (due to the expansion of the universe) are receding from us at the speed of light and so are no longer within our universe -- as we have no way of ever again observing them.

In the most common interpretation of Guth's inflationary scenario of the BB we are living in a "Cell Universe" that can be thought of as one of a large number of "bubbles" of the inflation. Each a separate universe as they are time-like separated.


As for "string theory" it has always been a theory only in name. While I stopped keeping up in the late 90's since in over 20 years it added a lot of new math but zero new physics. Things may have changed in the last few years, but the journals haven't trumpeted any great changes.

The only calculation possible with the string theory are at the Plank energy and these only to the first or second order of perturbation. ANY calculations at lower energies are really collapsing the calculations to that of QM field theory and using those calculation (since according to the stringer's) standard QM is contained in string theory the way classical mechanics is included in relativity theory.

One last point. In the 1980's when people were asking the stinger's why stop at strings, why not move on to higher order structures, i.e. membranes the answer was a conformationally invariant theory could not be made with higher order objects than strings.

By the md 1990's as the string regime was getting nowhere, suddenly they found what they thought "might" be a conformationally invariant membrane theory and I lost interest.

There is actually a more problematic basic problem with string/membrane theory that seems to be, so far, insurmountable.

Why are so many people working on it? Because QM seems to be at a standstill, they are mesmerized by the "beauty" of the math structures, and its hard to get grant money to work on nothing at all. It may eventually be turned into a theory and turn out to be true, but since its origins in the 20's as the Kalusa-Kline theory it has never been useful for any problem it was attempted to solve.

I never knew string theory had its origins in the kaluza klein theory, although that is probably where the idea of adding dimensions comes from.
Has the kaluza-klein theor been useful in its own right?

Thanks for the article, I read a bit of it. It's rather long. xD

Okay, so the second part you stated, what exactly is this theory based off of? And how would said objects be out of the universe (which, as far I know, "universe" means the entirety of existence)? And assuming there are objects outside of our ability to see them, what would be the reason to consider this?

As for the third, is there any logical reason whatsoever to believe such a claim of a "cell universe"?

Hi,
Yes the article is a bit lengthy but as you can imagine it is hard to do justice to this subject in any detail without some length. I like it because I think Davies did a good job of keeping it readable by interested non-specialists without losing the real flavor and content of the subject.

Yes the theory's creators had Kalusa in mind. In the 60-70s timeframe it was resurrected in a different way to describe strong force interactions. They envisioned a little elastic string holding the hadrons together. This failed because they couldn't get the real particles to come out of the theory but got super-massive particles, a group many, many times more massive than the ones that we see and another group (at the plank scale) that seemed then (and to many even now) absurd. Quantum chromodynamics was at the same time being invented and with the idea of gluons described strong force interactions nicely, fit with quantum electrodynamics and the weak theory, and allowed the unification of all three particle forces.

All that remained left was to add gravity and a "theory of everything" could be contemplated. Two guys, Green and Weinberg, went back to the old "string theory" because it contained a spin 2 particle which they thought might be a model of the graviton and a new string "theory" was begun. For all the hype it has really led nowhere in particular, so "M-theory" has evolved from it. That is the theory in a nutshell.

I'll answer your other questions as best I can later…client work calls.

If I understand your other questions:

The FRW model of the universe is the basic standard theory. Inflation has been added to it and is now generally considered within the "standard" model but there is enough disagreement on this that the term is usually added to denote uncertainty. For example the hot BB model vs. the inflationary hot BB model, etc.

The BB causes an expansion of space and the further objects are separated from each other the faster they are moving away. There would by now be objects (under most interpretations of the BB scenario) that are moving away from us at the speed of light or greater. This is possible because space is not analogous to matter in these theories in that in can exceed the speed of light in its expansion rate. In an inflationary model it exceeds the speed of light by many, many orders of magnitude. Since communication between space-like separated objects is not possible they can be said to be outside the universe (for those objects that have that separation with them). The concept of the "universe" in astronomy is a fluid concept, which is why we often see new terms like the multi-universe; Webster's definition of the universe (for example) is colloquial.

Depending upon which analysis of Guth's inflationary model you choose (there are several at least) the only way to keep inflation consistent with all the other physical laws is if the inflation took place in such a way as the separation of parts of the universe that were space like remained space-like forever.

BTW: Space-like separation is a short hand for two objects not within each others light-cone, i.e. for a signal from one to reach the other it would need to travel faster than the speed of light.

humans are gods in training.