Multiverse

[mickoking]

I am a firm believer in the multiverse hypothesis http://antwrp.gsfc.nasa.gov/apod/ap060301.html and it seems like some quaters are a little uncomfortable with it (sound familiar Galileo) ;)

[stinky]

If the universe(s) are independent of each other, have no influence/effect on each other, it can only ever be an idea with no scientificly verifiable basis.

If however there is influence / effect / between universes then they are not independent of each other therefore not seperate universes.

I always thought that the universe was the sum and total of everything?

[GrampianStars]

I think that there have been multiple "Big Bangs" and proberley still happen out there somewhere.
I also think they are not independant universes just the 1 universe with multiple starts which interact when the blast horizons meet.

[mickoking]

Maybe we should call the multiverse the Universe ?

[mickoking]

There is a theory I have heard that the gravity from the various universes leaks and effects other universes. This has been put forward for one reason for why the force of gravity is so much weaker than the other 3 forces (electromagnetic, strong nuclear and weak nuclear). the leaking gravity has also been put forward as an explanation for our own universe's cosmic accelaration.

cool stuff :thumbsup:

[stinky]

I guess if we ever detct the "graviton" then there may be ways of testing these hypothesis.

[ving]

you creat such interesting and thought provoking topics mick.... :)

[mickoking]

There was a special bought out by Astronomy magazine a couple of years ago called origin and fate of the universe. If you can track down a copy It's an interesting read.

[AGarvin]

I think this is tied in with string theory. From memory, it's not other universes but the other dimensions in string theory that gravity is bound up in, and appears very weak when in only experienced in our three dimensions.

Not 100% on that though, must be looking into it further.

[mickoking]

The Multiverse hypothesis is little more than speculation. But to me it makes sense.

[astroron]

If it is not testable then it is not Science but HYPOTHESES, and we can all HYPOTHASIS without fear of being wrong, to me it has to many flaws to be taken serously, but it sells good books.
Lets get the stuff we can test right before we start into the rhelm of fiction

[mickoking]

The sun centred solar system was once a hypothasis too. But to some it made sense and eventualy Kepler and Galileo proved that indeed the earth and other planets orbit the sun. Sometimes, some of us go out on a limb, that to me make's science exciting and a little reckless :D

[cometcatcher]

The concept of a multiverse is an interesting idea, and I suspect it might be true but that's more of a belief of mine more than anything else.

A popular belief with a lot of new age people too but then most of the ones I've met don't even have an idea of how our own universe works which is a pity.

Some people in the lucid dream internet group I frequent believe that our consciousness travels to other universes or dimentions when we sleep. Normally I wouldn't believe such notions and would consider them to be just creations of the physical mind but... I've had a couple of experiences that challenge that. I suppose if I told you I've been there you'd all think I was nuts. And you might be right. Unfortunatley like the film Contact, it's just as impossible to obtain any proof of it.

I want to wake up from this dream. I want to go back.

Pleasant dreams. :)

[avandonk]

I keep having this lucid dream I am stuck on an astronomy forum for eternity. I know it can't be real. Just have to wake up.

Bert

[astroron]

The sun centred solar system Hypothasis was testable, this dream time stuff is not.
It seems that anytime there is a dispute about something in science and you don't believe then people bring up Galileo as if you are an heriatic in reverse, such things such as string theory, which seem to be unravelling all the time which is a case in point.

[mickoking]

Very sorry If my opinion offends you. 100 years ago most people would have dismissed the Big Bang as dream time stuff too. To me the multiverse makes sense and if I am proved wrong I'll get over it.

[astroron]

Your opinion didn't offend me, I just don't think multiverse deserves the coverage it get's, you are quite entitled to your opinion and I would be the last to begrudge you it. I think it was Samual Clemments (Mark Twain) who said something like, I may not agree with what you say, but I will defend your right to say it.:) :thumbsup: :thumbsup:

[Rodstar]

So long as we are all honest about the fact that we conduct our lives relying upon a lot of beliefs which are not scientifically verifiable. :whistle:

[josh]

Humans seem to have a silly habit of thinking they know it all when they prove a few facts, then they see theres more to it, get some facts, we've got it !... then theres some more.....
Its a funny old ride, it seems we can only open our minds for short times make some obs and grab some facts, then clam up again to digest and become accustomed to our new knowledge, it seems to help our digestion if we can convince ourselves that we now know it all.
Multiverse.. bring it on and lets have a chew!

[jjjnettie]

SF Author Robert A Heinlein used the Multiverse in a few of his books, "The Number of the Beast" and "The Cat Who Walks through Walls" being just two.
He wrote about multiverses occuring due to time travel. eg if you went back in time, and prevented Hitlers conception, there would be a new universe / timeline made where there was no Hitler.
An interesting concept.

[mickoking]

The one question I have always had a problem with is, What happened before the big bang? To me there must have been a prior event that percipitated the BB, every thing has a cause and effect.

[cometcatcher]

Big crunch? Crunch/bang/crunch/bang?

[cometcatcher]

Theories often start with beliefs. Not all theories are testable due to technology limitations at a given time. But in a future time they may be.

If we limit ourselves to what is known and testable and there are no beliefs or theories then how can we advance in knowledge?

[jjjnettie]

Big Bang.
Maybe that is what happens after a Black Hole has gotten so big that it draws in all matter, collapses under it's own weight, then explodes the whole lot out again.
Not so much a Big Bang, as a Big Belch.

[astrofiend]

Ahh... Here it starts to really get interesting. Physics at the point of the Big Bang is foreign to us. General Revlativity implies that both space and time came into existence at the moment of the Big Bang, and that previous to that the Universe was a singularity. Hence you cannot talk about a 'before' because time literally started with this event. Quantum principles can help reintroduce causality in some sense, and physicists talk seriously about 'quantum fluctuations' initiating the event, though time itself did not exist as we know it at this point.

The problem with it all is General Rel and Quantum Mech. fail us at this point as they are mutually incompatible. They are not accurate descriptions of the universe in these extreme conditions. A new description is necessary, which is why the search is on for a theory of Quantum Gravity, of which GR and QM will be limiting cases. There are a multitude of candidates for QG.

Also, we have a fair idea of the characteristics of the universe during the BB event, such as what temperatures and pressures were reached, what must have happened afterwards and whatnot, but very little idea of what the BB event actually was. Hawking proposed that it all started with a singularity, but other ideas include collisions of higher dimensional spaces (branes), collapse/rebound theories and so forth!

The basic BB theory has had spectacular successes, but at the same time there are many things that it either cannot explain or are in outright contradiction of it. Also, current theories dealing with things such as dark matter and dark energy are essentially just patch jobs, showing that we still have only the vaguest idea of what is really going on.

Exciting times lie ahead - I love Science!

[mickoking]

It does look like we live in a golden age of cosmology. The universe (or multiverse :D ) is getting more bizarre and fascinating by the year.

[robagar]

yes, likewise superstring theory today. Been purely theoretical for ages, but finally possibly becoming testable at least indirectly. The most intriguing one for me is seeing if gravity square law breaks down at really small scales, indicating the existence of >3 space dimensions. (string theory predicts 6 or 7 extra, curled up really small)

[barees63]

FWIW, I just finished a really good book about this very subject: "Parallel Worlds: A Journey Through Creation, Higher Dimensions, and the Future of the Cosmos" by Michio Kaku.. well worth a read if you're interested in current cosmology (it's also at fictionwise for anyone reading on a PDA)..

[robagar]

Brian Greene's The Fabric of the Cosmos is also a good 'un

[glenc]

http://www.skyandtelescope.com/news/28528759.html
We usually think of the universe as being “everything there is.” But many astronomers and physicists now suspect that the universe we observe is just a small part of an unbelievably larger and richer cosmic structure, often called the “multiverse.” This mind-bending notion – that our universe may be just one of many, perhaps an infinite number, of real, physical universes – was front and center at a three-day conference entitled "A Debate in Cosmology — The Multiverse," held at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario, earlier this month...

[AlexN]

So... Do we have opinions on if the many "universes" within the "multiverse" occur in the same space/time except somewhat out of phase.... Provided that gravity is a multiversal constant (let us assume for a minute) This theory (brewed up in my own mind over the past couple of days thinking about it, so excuse its crudeness.) could help account for why gravity is the weakest force in our universe... Lets say for example, you have the multiverse containing several universes all sharing the multiverses gravity, obviously we would only be getting a small share of that gravity hence its weakness...

Its all fun to think about etc, but until it can even be studied, let alone be found true or untrue, I think the matter is best left alone...

Humans do have a tendancy to work things like this out when they need to... We figured out the world was round when our development came to a point where international trade was viable.... Or something like that...


WARNING : Everything contained in this post was pure opinion, and thinking out loud. Not intended to start debates, nor was it intended to be taken fairly seriously... (Read: Dont shoot me if I sound Insane :P )