Either Life Exists Elsewhere or The Universe is finite.

[grengrad]

[ QUOTE ]

Here's a thought:

According to this theory, someone, somewhere in the universe would have found or made a tool to destroy everything in the universe, and used it (since every possible version of every possible thing exists). Therefore, because the universe (and us) still exists, the universe either


[/ QUOTE ]

The theory is that a NON-ZERO probability will be repeated in an infinite universe. There is nothing to show that the ability to destroy the universe is a non-zero probability.

I have kicked a soccer ball before, so I know that the action of kicking a soccer ball can happen, therefore somewhere else in the universe someone else must have also kicked a soccer ball if it is infact infinite.

Since we can wager with some certainty that the universe has not been destroyed, we can assume that destroying universe is a ZERO probability event or the universe is finite. We cannot be sure which, but it does not prove the universe is finite.

The original poster has a basic axiom.
1. Because something has happened before, the chance of it happening again is greater than zero.

The number selection example is to show you that just because something is possible it doesn't mean the probability has to be greater then zero. As grump expounded on, and I could define this more formally. Given a one to one function on the interval [0,1] and a number given in the range of that function. The odds of you guessing one number and getting the corresponding value in the domain (which generates your initial value) is zero. Its not impossible but the probability is zero.

The deck example. After I have the two aces. You can shuffle the deck and draw two cards and infinite number of times. No matter what you will never get two black aces as long as I have them. Whats the point? After an event occurs the odds of it occuring again are not necessarily the same. They can go to zero.

Hence there is no reason to believe that the axiom is reasonable.

[adamstewart]

You are misconstruing my arguement.

Your example with the two black aces is not a proper analogy. You are comparing apples to oranges. That is, drawing to black aces from 52 card deck is not the same as drawing two black aces from a 50 card deck that does not contain the black aces. These are two totally different trials. One has a greater than zero probability. The other has a zero probability.


Also, if I am correctly understanding your proposed scenario of 'picking a real number between 0 and 1,' then I fail to see how this is the same as the argument propsed in my original post.


Adam

[bradha]

If the universe is finite, then it "ends" by having nothing but empty space past its "boundaries". If you accept the standard interpretations of astronomical data - increasing red-shift for more distant objects, etc. - then you are led to the expanding universe and big bang theory.

Personally, I think that the most likely thing is that we live on a finite planet, in a finite solar system, in a finite galaxy, in a finite (but expanding) universe. I think it quite possible that life exists elsewhere, but extremely unlikely that I will live long enough to see proof of that.

Obviously the "known universe" is finite - it consists of everything we have observed evidence of, so obviously it is finite. If we define the universe as everything known and unknown, then I don't think we can ever prove the "known and unknown" universe to be finite or infinite. However, if the known universe is always finite, it is possible that we will never know that life exists elsewhere.

[goofball]

The universe is not infinite.

[mmbt0ne]

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The probability of picking any number in the range of 0 to 1 is zero. If you are not even going to concede that point then there is no point in even having a discussion.

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I think we may not understand one another's argument. Admittedly, I have no idea what you are refering to above. Please clarify your point.

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It is impossible to calculate the probability that you select any single number between 0 and 1. If you try, you will only get zero. All we are able to do is calculate the probability that the number falls within a certain bound.

This is what people use the Poisson distribution for.

[Moon Double Comb]

[ QUOTE ]
And, given that the Universe started as a singularity - i.e. spatially restricted to a single point - and a limited time has passed since then, and nothing can travel faster than the speed of light (relative to anything else) it could never have become (yet or in the future) spatially infinite.

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This is not true. It's possible for space itself to expand faster than c. Compare it if you will with the difference between phase and group velocity of a wave. The phase velocity can be greater than c. The group velocity not (which is basically the max velocity at which information can be transmitted).

Let’s suppose that the world is the poker table, the cards are the phenomena of the universe and the rules of the game are the laws of Nature. The problem is that the player on the other side is hidden from you. Will you still want to play that game?

[nervous]

I believe that the original title is true. Either life exists elsewhere or the universe is finite. Isn't the theory that the universe has expanded from a single point until it has reached its "bounding limit" and at that point it begins to shrink until it becomes a single point again? At that time it will start the process all over again? This theory predicts that the universe is finite, so there is a possibility that there is no other life in the universe.

I agree with the OP that if the universe is in fact infinite, then there would be infinite forms of life on infinite other planets in infinite galaxies. Since this is presumably not the case, there may or may not be life elsewhere. It is still entirely possible that there is a solar system setup that mirrors the Earth and Sun enough to support life forms just as humans.

The picking a real number over (0,1) really has no relevance to this at all. If you compare the existence of life forms as being number 0 and a random number generator picking random real numbers over the period (-oo,oo), which I believe is a more relevant comparision, then there will be infinitely more planets with life forms.

[gumpzilla]

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The picking a real number over (0,1) really has no relevance to this at all. If you compare the existence of life forms as being number 0 and a random number generator picking random real numbers over the period (-oo,oo), which I believe is a more relevant comparision, then there will be infinitely more planets with life forms.

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