Infinity is god.

>>Guin forgive me but if the Universe is finite we should be a able to specify its size<<

Not necessarily. The current estimate of the age of the universe is about 14 billion years and consequently if it were not expanding, the size of the observable universe would be just 14 billion light years. However the universe has expanded during that 14 billion year period and there are observable objects that are now as far away as 46 billion light years.

Beyond a certain distance light from objects cannot reach us because the universe is expanding faster than the speed of light. To calculate the size of the expanding universe you would need to know the rate of expansion, which is not constant—it is accelerating—and that is a major difficulty. It is not known whether the rate of acceleration is constant.

It is not known whether the rate of acceleration is constant.

And that’s why there’s hope all those particles might eventually slow down and stop, then begin to coalesce

[Scott]

Not really, Dalehileman, because the acceleration being referred to is the acceleration of the rate at which the universe is expanding or in other words the acceleration of the rate of acceleration. The irony in terms of talking about particles stopping is that particles are more likely to stop in a so-called Big Freeze, which is the result of too much expansion, as opposed to everything collapsing back down into Big Bang-like conditions. The more particles, matter and by extension energy are squeezed together and put in a smaller space the hotter and more fast moving they get. So it seems to me that the so-called expansion of the universe (i.e. the movement of everything away from everything else on average) is inversely correlated to the amount of movement at the particle-level in a more local sense.

Yes, we should be able to determine the size of Multi Universe, or we feel incomplete, but we are not able yet. Only because we are not able yet, this inability can not force us to assume the infinite size of Multi Universe.

-- Updated Sat Apr 28, 2012 6:50 pm to add the following --

Guin forgive me but if the Universe is finite we should be a able to specify its size

Say I have a rubber bend. I stretch it maximally - it is one size. Then I let it contract- this is another size, and all the sizes in between. Can you determine what is the size of this bend? Plus, if there is nothing in space besides this bend ? What size is it then? Can you say that it is small, medium or large? Is it small like a speck or large like a mountain? At the point where nothing is larger than an object, all measurements loose their size orientation. This largest size, even if fluctuating ( contracting-expanding), is then equal to infinity.

more likely to stop in a so-called Big Freeze, which is the result of too much expansion, as opposed to everything collapsing back down into Big Bang-like conditions.

Yes that’s the current thinking but Intuition is dissatisfied with such a dreary hopeless prospect

So it seems to me that the so-called expansion of the universe (i.e. the movement of everything away from everything else on average) is inversely correlated to the amount of movement at the particle-level

If you’re saying the particles get colder as they fly apart, then yes that’s the way I understand it’s supposed to happen

Then in my Intuition however as I said after they come to a stop they begin to coalesce and of course in so doing so get hotter and hotter until a tiny very hot spec whereupon next Big Bang forever anon and no I don’t know why they should coalesce

It is not known whether the rate of acceleration is constant.

And that’s why there’s hope all those particles might eventually slow down and stop, then begin to coalesce

I would imagine that like a rubber bend, Universe would slowly stretch to maximally possible size and then it could very quickly bounce back, go crashing, creating a huge wave and a substantial hit at the end , and the power of this enormous moment of collapse onto itself considering the size of Universe could equal Big Bang.

this inability can not force us to assume the infinite size of Multi Universe.

No Guin I didn’t say it could

Your rubber band is beyond the comprehension of the Average Clod (me). It’s not my idea, I’ve only read somewhere that if the Universe is finite its size might be specified

Might be specified, perhaps. The trick with growing or larger and larger sizes is that at some point any other smaller measurement equals just one point: any planet, galaxy, even Universe. Say, this can be our first measurement of Universe - "it is a point in space". Not bad for starters. At least something.

In our human world, with our eyes, on our planet, not abstract world, sizes get lost below the dot, they exist above the dot, and get lost again after we see an ocean or a desert or a mountain range, or a canyon. This is wide range of sizes to enjoy dealing with in traditional human way. Yet for the sake of mental hunger we thrust ourselves into a pit of despair of discovering to be meaningless creatures by pushing too far ahead, towards yet another point in space making no point.

Sorry Guin but you’ve left this Average Clod out in the cold so to speak. You might enlarge upon it a bit in order to clarify

When we go deep into grandness of cosmic bodies, galaxies, Universes, it is like we are saying "Yeah, Universe did us", because we are so insignificantly tiny, we are not even star dust, but lesser, we are nothing. A tiny splash, an accidental wave, a vapor, a stray ray. Should we shush our ambitions and enjoy our human life instead of proving what we already know - that Universe did us.

When we go deep into grandness of cosmic bodies, galaxies, Universes, it is like we are saying "Yeah, Universe did us", because we are so insignificantly tiny, we are not even star dust, but lesser, we are nothing. A tiny splash, an accidental wave, a vapor, a stray ray. Should we shush our ambitions and enjoy our human life instead of proving what we already know - that Universe did us.

We would not even know how insignificant we are in the vast universe if those who went before had not been curious about what is out there. We would still believe that the sun went around the earth and that the stars were quite close to us. Only centuries of effort and ingenuity have allowed us to arrive at a more accurate picture of our universe. That is what tells us that we are not the center of it, perhaps not very important.

On the other hand we know of no other examples of intelligent life in the universe. Probability suggests that there is life elsewhere, but what pattern of development it has undergone is for the moment a closed book and likely to remain so for a long time. We could be the most advanced form of life there is anywhere. We are likely unique even if not the only advanced life there is. The questions about how the universe developed and how we evolved in it are among the most interesting remaining to be understood. That life has managed to sustain itself and evolve in a universe that seems quite indifferent to our existence is a surprising thing to me—a subject of endless fascination.

Suppose we knew there is no advanced life anywhere else. Wouldn't it seem more important to preserve the earth and its creatures against annihilation and extinction?

We could be the most advanced form of life there is anywhere

Yes we could but it’s doubtful

We are likely unique

Recent speculation has more planets than stars. Given around 3 billion stars in each of a like number of galaxies, and given only one habitable planet in each, a very conservative estimate posits three sextillion of us

Wouldn't it seem more important to preserve the earth and its creatures against annihilation and extinction?

While we’re already overpopulated by some 5 to 20 times, if there’s a God I herewith thank Her for allowing me to live most of my life between nuclear wars

Recent speculation has more planets than stars. Given around 3 billion stars in each of a like number of galaxies, and given only one habitable planet in each, a very conservative estimate posits three sextillion of us

The problem is that we have no idea how likely life is. It may be quite likely under the right conditions or it may not be likely at all. There is no way to assign a meaningful probability to it.

Wouldn't it seem more important to preserve the earth and its creatures against annihilation and extinction?

Space exploration is a sword with two sharp ends, because out there might be the species that will innihilate us, intentionally or not, right after we make contact with them. We can bring from space unknown harmful viruses, contaminate Earth with alien materials that might speed up our doom. I guess, we, Earthlians, are risk takers. I just can't forget how native Americans kept wondering about how many white people are coming, they lost hope of overpowering them, and so great nations are no more. It's like mini version of alien invasion for all the Earthlians, a life size warning.

There is no way to assign a meaningful probability to it.

True Mat, only Intuition but we’d be pretty cavalier in supposing we’re alone; while it’s a good guess that huge numbers of planets share the conditions that make life possible