Do you think any aliens exist in the universe?

[aupmanyav]

I foresee worms that eat ziplocks, crocks, grocery bags, plastic peanuts, candy wrappers and dry cleaning bags, growing to tremendous size, emerging from the landfills and heading for town, protected by their lexan-like exoskeletons …

Won't that be nice?

There is a thing that amuses me more and more as I age. It’s how we humans are confident of our species’ survival to cosmic ages. I see no reason not to expect us to eventually number among the VAST majority of species - more than 99% of all species ever on earth - that are kaput.

Has not God created us for a special purpose .. to worship him. So, we will survive.

A bit of atheist fun. Won't it be nice if ice creme or kebabs become twice as large.

 

[aupmanyav]

Has not God created us for a special purpose .. to worship him. So, we will survive.

Well, NO. Humans created gods ... to scam other humans.

Aouth American will come closer to India.

You do know that map is of 250 million years AGO (in the past), right? Not where India will be in the future.
I'm thinking we'll be closer to the Mariana Trench in 250 million years.

Ah, you forget! God is testing us. That is why he had given us free-will.

Why would god test us? Doesn't he trust his handywork? Testing is what an imperfect mortal would do. god is too human to be a real god.

1. That is true for atheists, and not for theists.
2. Yeah I know, we were close to Africa and Madagaskar was practically a part of India (or vice-versa).
So easy to find on internet. The latest news is that Tibet may be breaking into two portions.
3. Fun, sarcasm for those who think so.

.

 

[Swammerdami]

Long ago I came across an interesting sci-fi story whose title I don't remember ("[Something] Andromeda" maybe?); I don't remember if it was a book or a movie.

Anyway, the enemy aliens have no intention of arriving at all. They just send a radio message which, when decoded, is detailed blueprints for a big computer system. The humans eagerly build this super-computer ... which turns out to be very powerful, in control of Earth and forcing the humans to build more copies of itself!

... Or something like that. Anyone know what my vague memory remembers?

 

[Elixir]

I foresee worms that eat ziplocks, crocks, grocery bags, plastic peanuts, candy wrappers and dry cleaning bags, growing to tremendous size, emerging from the landfills and heading for town, protected by their lexan-like exoskeletons …

Won't that be nice?

There is a thing that amuses me more and more as I age. It’s how we humans are confident of our species’ survival to cosmic ages. I see no reason not to expect us to eventually number among the VAST majority of species - more than 99% of all species ever on earth - that are kaput.

Has not God created us for a special purpose .. to worship him. So, we will survive.

Oh bullshit. Any old vertebrate can worship a god better than humans. Human worship is always undergirded by the fleeting awareness that god is a fantasy.

 

[Tannhäuser Rover]

Elon Musk talking about aliens:

1:39

I think it was Carl Sagan that said there either are a lot of aliens or none and they're equally terrifying

Elon Musk has also said he thinks we're probably in a simulation/video game:


Then there is this:

Exoplanet - Wikipedia

en.wikipedia.org

it can be hypothesized that there are 11 billion potentially habitable Earth-sized planets in the Milky Way

As a believer in the video game explanation my explanation for the apparent absence of aliens is to keep the costs of the video game low. I mean if you're looking at a typical distant star that apparently involves 10^57 atoms it can be approximated to us viewing it a lot more cheaply than if it had a Matrioshka brain attached or some nearby civilizations even though it might involve less than double the apparent atoms of the star on its own.

It is related to how likely evolution is. Either it is highly unlikely meaning that it rarely happens (e.g. once in the universe or our galaxy) or it is quite likely.... (or in-between)

My belief is that our simulation only started relatively recently and a virtual evolutionary history is worked out later on e.g.

View attachment 38724

Hello. This is my first post on this forum so I'm choosing a 'light' topic... I have often thought that maybe we are just part of a video game, with the alien version of a teenager playing SimUniverse II, or Planet Maker IV

On a more serious note, I always felt quite skeptic about the existence of Alien civilizations, and I always thought that the Drake Equation is flawed. However the sheer size of the Universe makes me conclude that, even if extremely rare, some Alien civilization probably does exist, or has existed, or it will. Current evidence suggests that the universe is flat, and considering the margin of error some astronomers have estimated that it is at least 250 times larger than the observable universe. Another estimate gives a minimum diameter of 23 trillion light years. That's a lot of universe... And it is not ruled out that it is actually infinite.

 

[pood]

I think the preponderance of empirical data is that it is probably spatially infinite, which means we ought to expect an infinite number of alien civilizations no matter how rare they are.

 

[WAB]

If there were no alien life forms in the universe other than on Earth, I would consider that more of a miracle than divine creation.

 

[Loren Pechtel]

I think the preponderance of empirical data is that it is probably spatially infinite, which means we ought to expect an infinite number of alien civilizations no matter how rare they are.

I'm not convinced it's infinite.

However, look at Earth. Life appears to have evolved as soon as conditions were tolerable. Something that happens fast is probably reasonably likely (given the time scale involved.) Is there anything stupendously unusual about Earth? No. (And note that Jupiter has been discredited--yes, it sweeps away some threats, but it creates more than it averts.) Thus the reasonable conclusion is that life should be abundant. Civilizations, though?

It took a long time for life to go from simple to more complex. While that does not say it's impossible it suggests that for many planets it might take too long.

It took a long time to go from more complex stuff to intelligence. Again, maybe time.

And there's a strong reason to think time might be relevant: We are at about the 99% mark on the time when Earth could develop an intelligent species. Soon CO2 will go as low as the plants can tolerate, the mercury will rise anyway, hugely favoring stuff with fast reproductive cycles.

But there's also the possibility that civilization destroys itself. Unfortunately, it certainly looks like that's going to be our fate.

 

[pood]

I think the preponderance of empirical data is that it is probably spatially infinite, which means we ought to expect an infinite number of alien civilizations no matter how rare they are.

I'm not convinced it's infinite.

However, look at Earth. Life appears to have evolved as soon as conditions were tolerable. Something that happens fast is probably reasonably likely (given the time scale involved.) Is there anything stupendously unusual about Earth? No. (And note that Jupiter has been discredited--yes, it sweeps away some threats, but it creates more than it averts.) Thus the reasonable conclusion is that life should be abundant. Civilizations, though?

It took a long time for life to go from simple to more complex. While that does not say it's impossible it suggests that for many planets it might take too long.

It took a long time to go from more complex stuff to intelligence. Again, maybe time.

And there's a strong reason to think time might be relevant: We are at about the 99% mark on the time when Earth could develop an intelligent species. Soon CO2 will go as low as the plants can tolerate, the mercury will rise anyway, hugely favoring stuff with fast reproductive cycles.

But there's also the possibility that civilization destroys itself. Unfortunately, it certainly looks like that's going to be our fate.

The evidence suggests it is flat at very large scales, which suggests but does not prove it is infinite. If it is not, it must have negative or positive curvature. However, all this would be way beyond the observable universe and is immune to verification or falsification.

I just read that it is now thought that the Hycean worlds probably are not water worlds as previously thought.

Who knows? But in a universe as vast as this, even if not infinite, there must at least be some inhabited worlds besides our own. Technological intelligence is a different matter.

But as noted in another thread, scientists say they have the clearest evidence so far of possible ancient Mars life, so we will see. I only regret I almost certainly will not live long enough to see extraterrestrial life confirmed.

 

[bilby]

Is there anything stupendously unusual about Earth?

It has a single very large moon.

https://xkcd.com/3135

 

[bilby]

But in a universe as vast as this, even if not infinite, there must at least be some inhabited worlds besides our own.

Sure; But it doesn't matter. Distance is as important as existence. A civilisation outside the observable universe is indistinguishable from non-existent.

And how close a civilisation needs to be depends on what our objective is. Mere detection is beyond our abilities for a civilisation more than a few tens of ly away, or for life (civilised or not) more than a few hundred*.

To interact with aliens (even by exchange of messages, not physical meetings) would require them to be practically on our doorstep - which restricts the number of possible locations so much that it is far from surprising that they aren't here. After all, we aren't there, either.







* Depending on how rigorous we feel the need to be. If we accept detection of water and O₂ as 'detecting life' we can do that at very long range; But bear in mind that Mars life is still neither confirmed nor disproven, and we are only 0.000005 ly away from that planet.

 

[Shadowy Man]

Is there anything stupendously unusual about Earth?

It has a single very large moon.

https://xkcd.com/3135

Even crazier is that that large moon has almost exactly the same angular size as the Sun as seen from the surface of the Earth in modern times.

 

[bilby]

Even crazier is that that large moon has almost exactly the same angular size as the Sun as seen from the surface of the Earth in modern times.

That makes for some impressive visuals once in a while, but I hardly think their importance can eclipse that of the tides.

 

[Shadowy Man]

Even crazier is that that large moon has almost exactly the same angular size as the Sun as seen from the surface of the Earth in modern times.

That makes for some impressive visuals once in a while, but I hardly think their importance can eclipse that of the tides.

But the question was what might be stupendously unusual about the Earth. the existence of a moon of that size may be unusual (we don't really know yet), but tides as a result are perfectly reasonable physical result.

However, the coincidence of the angular sizes seems quite remarkable to me, even if there are other Earth like planets with large moons, given that the distance between a planet and its singular natural satellite would seem to be a continuous possibility.

 

[bilby]

But the question was what might be stupendously unusual about the Earth. the existence of a moon of that size may be unusual (we don't really know yet), but tides as a result are perfectly reasonable physical result.

If current ideas about how the moon formed are correct, we should expect planets with oceans, and also with large moons able to cause large tides, to be fairly rare.

It doesn't seem like much of a stretch to hypothesise that large tides might be necessary for, or might massively accelerate, the movement of life from water onto land.

Land based life is likely a prerequisite for technology - even the most intelligent aquatic life is going to struggle to harness fire as a tool.

However, the coincidence of the angular sizes seems quite remarkable to me, even if there are other Earth like planets with large moons, given that the distance between a planet and its singular natural satellite would seem to be a continuous possibility.

Indeed. Though my "objection" was on two grounds:

1) The context of the discussion is the development of technologicslly advanced life, and the unstated criterion in @Loren Pechtel's post was that the unique feature should assist somehow in achieving that end. I am struggling to see how eclipses could assist with that, though once such a civilisation has arisen, they do make it much easier to study the Sun's corona. And (much more importantly);

2) I needed to make some kind of pun, however feeble, on the word 'eclipse'.