are we alone in the universe?

[KenWittlief]

Originally Posted by sanddrag

Very interesting read. Thanks.

I have a question about one thing. You say that if life on earth dies (and assuming it is the only life in the universe) then the universe will "burn out" before the "blender" can recombine all the atoms into DNA again, therfore there will be no more life.

My question is which is longer, the time between the "big bang" and now or the time between now and the "heat death" or burn out?

Because if the time between now and the "heat death" burnout is more than the time between the "big bang" and now, then how did all the atoms have enough time to correctly combine to make life in the first place if they wouldn't have time to reorganize before the burnout?

Also, while you probably are correct in saying there wouldn't be enough time to try all the combinations of atoms, it does only take once to get it right. It wouldn't necessarily be the last possible combination that it works out right. You might get it on the firs try. Just like, to absolutely win the lotto it would cost more to buy all the tickets than what you would win, but all it takes to win is that one "lucky" ticket which can come at any time without having to buy all the tickets.

I will try to hit all the questions and points raised so far in this thread in this one reply.

Probability tells us how likely something is to occur. While its true that is is possible to win the lottery the first time you play, and then to win it again the second time you play, its not very likely

and the question is, what course does humanity take, based on the scientific evidence, based on what we know. I could have taken all my college tuition money and spent it on lottery tickets instead of becoming an engineer, and I might have made a million dollars that way, but I would have no control over that outcome. By getting my BSEE degree, and working as an engineer for the last 21 years, I have earned $1.2M dollars so far. I have played the lottery from time to time over those 20 years, and I think maybe Ive won $40 total

probability tells us what we should do to have the best chance of success.

If something has 1E3 possible combinations then you have to have 1000 random trials on average to get the desired outcome to happen once. If you have 100,000 trials, then it really does average out that you will see your desired outcome around 100 times. If not, then the thing you are predicting is not really random.

So, how long till heat death? on average we would have to get another 1E250 seconds before we can reasonably expect to see life happen again spontainiously, and that is assuming every single atom in the universe is recombining once every second in a place where life COULD exist if it happened to assemble by chance. In my equation I used every single atom in the universe, including the atoms that are in the stars, and the cores of all planets, and drifting through space. Obviously if any of those atoms assembled into a single cell lifeform by random chance, it could not survive or reproduce.

On the comments about the universe being infinite, its not. Everything we are able to observe says the entire universe began at one point, and spread out from there, around 16 billion years ago. If something started from a single point, with a fixed amount of mass and energy, then it cannot 'become infinite' no matter how long you wait. If there are other 'universes' (Im mangling the word here) that are so far away that we cant detect them, then for all practical purposes they dont exist, because we will never have a means of interacting with them.

The universe is expanding at a rate that will keep it from collasping back in on itself. This has been confirmed by recent observations. In fact, the universe is expanding at an accelerating rate, something we are at a total loss to explain, without involking things like anti-gravity particles (something we have never observed).

Someone has calculated that one civilization able to travel from star to star at sublight speeds would be able to expand out and colonize our entire galaxy, and it would only take them 2 million years. As another has pointed out in this thread, since the universe is 16 billion years ago, 2 million years is a very small fraction. If anyone is out there, they should have colonized the entire galaxy by now, they should have been here many times over.

bottom line is, as far as we are able to observe, and from what we know about the size of the universe and the complexity required for life to establish itself: we are (most likely) entirely alone.

I agree humanity ultimately must attempt to colonize elsewhere. However, I don't think doing it for the sake of doing it will be a popular opinion. In order to spend the energy on trying to journey to another galaxy, there would have to be a strong reason that our own is in danger (or we could make some serious money doing so).

I agree, this understanding calls for a new way of thinking for our species - to see ourselves not as individuals, not even as a species, but as the only lifeform in existance that has the ability to carry life from one star system to another. We dont have to jump from galaxy to galaxy. Jumping from star to star will do (for the next few billion years at least).

I cant see our culture launching any nationalized efforts towards this goal in my lifetime, but I can see our species stepping up to the plate in a hundred years or so, and begin an organized effort.

In the meantime, I think the most we can hope for is individuals seeing the reality of this, and slowly it will begin to change the way we see ourselves, our relationship with with the other lifeforms on this planet, and our purpose in the universe.