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We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 6:14 am
by doubtingthomas
Fraser Cain made some powerful arguments for the hypothesis that we are alone in the universe.
https://open.spotify.com/episode/7K3HHdxIt8dRYesXmpQ2kV

Three weeks ago, Dr. Kipping gave a fantastic lecture at Columbia University on the same subject, "Why we might be alone".
https://www.youtube.com/watch?v=zcInt58juL4

The "We are alone" hypothesis contradicts D&C 76:24, unless apologists want to claim that D&C was talking about worlds in some other universe.
If we are alone in the universe, that would be a big blow to the Fine-Tuning for life theory.

In any case, the evidence is overwhelming that intelligent life in the universe is not very common.

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 6:43 am
by drumdude
Can you summarize the argument? I don’t see how we can have overwhelming evidence either way given the fact that the speed of light is so slow, and the distances between galaxies are so vast.

If we are the only intelligent life in the universe, it goes very much against the Copernican principle, that we should be very skeptical about any claims that we or our place in the cosmos is unique.

Even if there is tons of intelligent life out there, space travel is almost impossible to solve without some sort of way around the speed of light limitation. It takes 8 full minutes just for a signal from the Sun to arrive at Earth.

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 6:07 pm
by KevinSim
drumdude wrote:
Fri Dec 30, 2022 6:43 am
If we are the only intelligent life in the universe, it goes very much against the Copernican principle, that we should be very skeptical about any claims that we or our place in the cosmos is unique.
The mentioned Copernican principle often applies; I know of no reason to believe it always has to apply. I think the best possible explanation for the available evidence is that we are the first intelligent life to come into being in the universe. Or at least among the first. It's possible that another form of intelligent life arose first but the speed of light has kept evidence of that intelligence from reaching us yet. So if intelligent life started generating radio signals 900 years ago on a planet a thousand light years from us, we wouldn't notice it for another century.

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 6:46 pm
by toon
What about the multiverse.

Or, in the event we're part of an A.I. simulation, how many A.I. simulations are there out there? And can separate A.I. simulations in the same universe be considered separate universes?

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 6:49 pm
by Everybody Wang Chung
Well, there might be billions of intelligent civilizations in the universe, but we will never be able to reach or observe them.

About 94% of the universe is completely unreachable to us, even if we could travel at the speed of light. To reach the other almost 6% we would need to be able to travel close to the speed of light for billions of years to reach.

Basically, almost 100% of the universe is unreachable to us. We are in essence alone in the universe. We came about 13 billion years too late in the game.

https://bigthink.com/starts-with-a-bang ... reachable/

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 10:02 pm
by Physics Guy
True, most of the universe will be unreachable unless we find lots of wormholes or something. The part that is in principle reachable is still staggeringly vast, though. Even just within 100 light years from our sun there are tens of thousands of other stars, most of which now seem likely to have planets of some kind. So depending on how common intelligent life is, given a planet, and on how patient interstellar civilisations can be about communicating with each other, we might even have many neighbours with whom we can actually communicate. There might be some lag issues.

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 10:05 pm
by doubtingthomas
drumdude wrote:
Fri Dec 30, 2022 6:43 am
Can you summarize the argument? I don’t see how we can have overwhelming evidence either way given the fact that the speed of light is so slow, and the distances between galaxies are so vast.
Cain made a lot of arguments, but let me mention two

1. There are no alien probes orbiting the earth . Humanity is only about 100 years away from building Von Neumann probes, so if there's an advance alien civilization in the galaxy, we should expect to see alien probes.

2. An expanding alien civilization traveling close to the speed of light would be obvious.
drumdude wrote:
Fri Dec 30, 2022 6:43 am
If we are the only intelligent life in the universe, it goes very much against the Copernican principle, that we should be very skeptical about any claims that we or our place in the cosmos is unique.
Dr. Kipping (an atheist) addresses that in his lecture and explains why agnosticism is a better position.
drumdude wrote:
Fri Dec 30, 2022 6:43 am
Even if there is tons of intelligent life out there, space travel is almost impossible to solve without some sort of way around the speed of light limitation. It takes 8 full minutes just for a signal from the Sun to arrive at Earth.
Civilizations moving at near light speed would age more slowly. It's called Time dilation.
https://www.technologyreview.com/2019/1 ... ce-travel/
toon wrote:
Fri Dec 30, 2022 6:46 pm
What about the multiverse.
It's possible and likely.
Everybody Wang Chung wrote:
Fri Dec 30, 2022 6:49 pm
Well, there might be billions of intelligent civilizations in the universe, but we will never be able to reach or observe them.
Dr. Kipping points out that our sun and the solar system are unusual.
"Is the Sun Unusual?"
https://www.youtube.com/watch?v=TAQKJ41eDTs

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 10:36 pm
by Gadianton
1. There are no alien probes orbiting the earth . Humanity is only about 100 years away from building Von Neumann probes, so if there's an advance alien civilization in the galaxy, we should expect to see alien probes.
What do you think UAPs are?

Even if you don't believe UAPs are probes, if there were advanced alien civilizations that sent out probes, we'd expect them to act similarly to UAPs -- get close but evade contact.

Anyway, I'd avoid too much investment in any of these "alien" theories. Speculations about alien life has nearly become a replacement for theology. Nobody is going to figure out if there's aliens by these a priori thought exercises.

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 10:38 pm
by Gadianton
Dr. Kipping (an atheist) addresses that in his lecture and explains why agnosticism is a better position.
I give it 10-1 odds that Kipping has never looked up the definition of "atheism".

Re: We Might Be Alone in the Universe

Posted: Fri Dec 30, 2022 10:58 pm
by drumdude
Just to throw around some orders of magnitude:

100 billion stars in our galaxy alone. 1-10 planets in each of those systems, so let's say on the order of 1 trillion planets in our galaxy.

Our galaxy is one of around another 1 trillion galaxies. So that's 1,000,000,000,000,000,000,000,000 planets which have been rolling the dice for around 10 billion years. Remember that life on earth started very quickly, almost immediately after the planet cooled.

It takes a lot of faith to believe that none of those dice rolls came up with life except us.