What are the chances...

[Draconiator]

of there being a world EXACTLY like our own somewhere out there, I mean the same distance to it's sun...everything. It could even have early life, like the equivalent to dinosaurs on earth. Sorry I'm not making much sense, but I'm being rushed...Going downtown today with a family member

[Tetzauh]

Well, what are the odds that a bunch of atoms created in the heart of a star got together is such a complex way that they have to go downtown with a relative?

I mean, everyting is possible until proven otherwise.

[Cham]

Well, if the universe is really infinite, and there's matter everywhere, some people think the probability is 1 (100%) to have another world exactly the same as ours, somewhere.

But to reach it, you would have to go a VERY long distance. It's probably on the other side of the cosmological horizon, which means it is in some causally disconnected region from ours.

Personnaly, I don't believe all this non-sense. Probability is one thing, but reality is another thing.

I mean, everyting is impossible until proven otherwise.

[eburacum45]

The odds have been calculated; from a famous article by Max Tegmark, referenced on this page,
http://www.cliftonunitarian.com/toddsta ... verses.htm

this;

Assuming the uniform distribution of matter indicative of our universe is typical, cosmologists go so far as to predict your closest doppelganger is 10 to the 10^28 meters away, and at 10 to the 10^92 meters away there exists a solar system identical to ours, and at 10 to the 10^118 meters away is an entire universe just like ours.

All safely outside our event horizon so you will never get to meet your doppleganger (if any).

[Cham]

The odds have been calculated; from a famous article by Max Tegmark, referenced on this page,
http://www.cliftonunitarian.com/toddsta ... verses.htm

This page is interesting, but it's really about metaphysics.

[eburacum]

Yes; that is right; but it does demonstrate pretty effectively that,
despite the billions and billions of galaxies visible in the sky

a doppleganger world, and a copy of ourselves, is extremely unlikely within our event horizon.

[Matt McIrvin]

The odds have been calculated; from a famous article by Max Tegmark, referenced on this page,
http://www.cliftonunitarian.com/toddsta ... verses.htm

This page is interesting, but it's really about metaphysics.

The author (not Tegmark) does go off the rails a little with his speculations about consciousness crossing the boundaries of parallel quantum worlds. According to standard QM, at least, if that interpretation is true, then those other branches are impossible to contact once they decohere with ours (or, rather, so difficult to contact that "impossible" seems an entirely appropriate word). You'd need not just different metaphysics, but different physics to have it otherwise.

...On the other hand, we do live in a superposed world to some small extent: when you do the double-slit experiment and detect a photon at the end of its journey, which photon-path world was yours?

[Seb]

I'm going to stick my neck out on this one... I think the universe is full of life, just mostly not very intelligent life.

It has been shown that bacteria can be brought back to life after long trips through the vacuum of space. And we have found life in the most remote and unbelievably the most uninhabitable parts of our planet.

Also, it seems our current technology is only capable of seeing the suns of other solar systems, not the planets. I personally believe large proportions of these suns do have planets orbiting, and a small portion of them will have a planet that has a habitable environment.

These two things lead me to believe there has got to be plenty of life out there.

The problem is, If there were any intelligent life near by, I'm sure we would of heard some kind of radio transmissions by now.

With Mars; if they do find water, I bet it wouldn’t take much to take one of our most resilient insect species to survive in the water there (not very long without a food source though). If that was proved; this I think also greatly increases the chances of the other life.