believe that since our universe is expanding is it possible for our galaxies to collide with other galaxies from a different big bang or is our universe the only one.obviously i'm asking this cause i believe the universe is infinite.

Yes, it is certainly possible for our galaxy to colide with others. What happens is that there is a battle between the forces of gravity between the two galaxies (which is trying to pull them together) and the expansion of the universe (which is trying to pull them apart). With galaxies that start out quite close together, it is almost always gravity that wins, so in the end the galaxies will collide.

When refering to "our" universe being the only one; That would be correct (hence the prefix "uni.") But... although completely theoretical, there maybe a point in space/time called "singularity" at which all physical laws may cease to exist, thus becoming "multiversal" at that point, and allowing parallel universes to possibily exist.

There is a little bit of mixing "apples and oranges" in your question.

If you take the viewable universe that current theory says originated with a big bang, the current number of galaxies that are careening around and colliding (the Milky Way is colliding with several small ones as we speak and will collide with Andromeda soon)then our universe is a closed system where all viewable galaxies originated here.

However, the term "universe" is a mathematical term which means different things in different context. In the multiverse theory, our universe is just one of many where the "space" to contain them may be infinite.

In our universe "space" is a fabric that contains time and expands in volume from the force of the big bang and the presence of dark energy.

"Space" may exist in a different form in another universe.

too much iron maiden for you!!!

Hi Katt

i was trying to make it simple but i meant more as there maybe more than one big bang that happend and maybe in another billion years our universe since it is expanding in all directions,and i know different galaxies travel at different speeds...is it possible that in the far outreach of space that another event such as ours happened out there and our universe collides with it...in other words multi-universes colliding or is the existing universe the only one


excluding the bubble theory

If the "Boiling Sea" theory of the universe is correct yes it is totally possible but we are not sure how big our expanse of the universe is and also we have yet to see evidence of another one in the relatively same vicinity of ours. Our universe may not have expanded enough to come into contact or become visible to another bubble of creation within our 'space.'

I forget the timeline but its something like 100,000,000 light years from now they anticipate Andromeda and Milky Way will collide.

hey but they give me piece of mind

Excluding the bubble theory changes all the rules. The basic theory of cosmology now is that the space we live in was created as a bubble of space/time by the big bang. For other big bangs to co-exist and expand to meet us from some far distance doesn't really make sense since the bubble we live in is space and time itself. Two bubbles of space/time growing to meet each other are existing in what? Hyperspace? The emptiness between them is what if not space? spacetime without the time? the proverbial timeless void?

In the current multiverse theory there are infinite universes of many shapes who float around in hyperspace and the chance collision between two of them MAY be what causes a big bang.

Some history.

http://www.youtube.com/watch?v=CEQouX5U0fc&NR=1&feature=fvwp

and if you want some visuals to trip on ... here is some fun.

http://www.youtube.com/watch?v=xE7xRgfPjAI&NR=1

With something that is not verifiable with our limited access, anything is possible.

Excluding the bubble theory changes all the rules. The basic theory of cosmology now is that the space we live in was created as a bubble of space/time by the big bang. For other big bangs to co-exist and expand to meet us from some far distance doesn't really make sense since the bubble we live in is space and time itself. Two bubbles of space/time growing to meet each other are existing in what? Hyperspace? The emptiness between them is what if not space? spacetime without the time? the proverbial timeless void?

In the current multiverse theory there are infinite universes of many shapes who float around in hyperspace and the chance collision between two of them MAY be what causes a big bang.


is this what you believe,cause i'm curious what people believe or do you have your own conclusion. our universe is the only one which is what i believe and its infinite,but i was wondering if it was plausable about there being another universe out there

i kind of got into quantom physics(reading about it) to see if maybe there was an answer to what happened before the big bang well it seems to fallback on the answer of nothing,really thats the answer.

so if nothing happened before the bing bang,then theres a whole lot of nothing that existed(i know seems weird) which could mean that what occured for the creation of our universe the big bang could have happened further away in the nothingness meaning another big bang occured somewhere.

We don't know. The limit of our light speed contained vision abilitities prevents us from 'seeing' outside of our own universe.

Therefore our scientists can cling to the 'flat earth' theroy (we are the only universe) til some 'explorer' comes along and disproves it.

If such a collision did occur at the fringes of our 'universe' how long would it be before we 'saw' the 'signature' of it?

the spaces - dark matter (or energy) referred to above - a theory first proposed and then discarded by einstein is now resurfacing to explain that which exists between particles in space (or objects). Time is a human construct and measurement to explain and measure the universe in terms we can understand along with light.

So our bubble is what we say it is because we say it is based on the laws of nature as we currently understand them - how useful are the laws of nature, or our constructs of measurement beyond our ability to measure. Well, how well do you conceptualize infinity?

As long as they are not taking a piece of your mind.

I think that you are conceiving of our universe as a collection of matter/energy expanding in space. I think you are thinking that all of the matter/energy came from the big bang, and that the tapestry of space is permanent and infinite and there for the matter/energy to move across, expand into.

From this point of view, it would make sense to question whether there would be multiple big bangs, and sets of galaxies from different sources colliding with each other.

This whole line of thought, however, is completely contrary to what modern physicists mean by the words 'universe' and 'big bang', as others have explained.

Why do you believe our universe is infinite?

I'm glad that doesn't apply to our models of cosmology.

The whole concept of 'before' doesn't really apply; there is no 'before' the big bang (per modern physicists) time itself, as we know it, began then.

If you meant 'some weird kind of otherness', than yes, we can't rule out that there might be other universes with their own big bangs. This thread has brought up the question of the interaction of these -verses. This is a strange concept, I don't know how separate universes would interact (if the could), but given the topology it would be a lot weirder than collisions of galaxies within our spacetime.