For visitations yes, but for interstellar travel otherwise it's a different story.

You can find many theoretical calculations about how it is possible to populate the galaxy in 1-100 million years, never going faster than light, or even close to the speed of light.

Basically it means sending out generation ships, which when in whatever destination they are at, in turn send new generation ships further out. The classic strategy game scenario, that is.

And that brings us back to the Fermi paradox. If there are some aliens who are millions of years ahead of us in their technology, then why haven't they already spread out all over the galaxy?

Even if most alien races wouldn't bother, and would rather stay at home playing good old video games, even if there's one race that takes the challenge, we should see it. Because we don't, then it's very likely that there simply isn't anyone out there to try anything like that.

Unless future humans do it. It's not very likely though, for the last 50 years humans have talked about going to places in space, but haven't really gone anywhere. At least these new commercial guys get something done too, although it's a long way from William Shatner's 10 minute space jump to populating the entire galaxy...

No.

But rather than leaving it at such a simple blunt statement, I'll explain.

Consider the cryptid. We live in such an era and time that one could take a photo, and nigh instantaneously upload it to a massive network of computers for instant verification and lauding. And yet none sane or rational has presented absolute proof irrefutable of such a creature's existence. Simply change the cryptid's origin to extraplanitary, and behold.

Think of the people who are claimant to such sightings:

1) Alone, no witnesses to actually back their claims.
2) In a farce of circumstance, somehow unaware of strange circumstances.
3) Always somehow end up somewhere quite near to where they had been "abducted" from, instead of appearing on the Kinzua Sky Walk, several thousands of kilometers from where they should be.

Considering how vast the universe is and how relatively little we actually know about our very own galaxy it's impossible that anyone could say in any absolute way that we are the only intelligent species in existence.

Aliens, yes why not. Universe is just too large and it is impossible to say wheter or not life can exist on other planets.

Vistiations, no. Physically impossible.

How is not knowing a reason for a action or non-action a paradox?
We can not assume that we understand how another life form thinks. But let's just assume they think like we do. That would mean they never got interstellar travel working, because they got themselves extinct long before that.

ps: The Fermi paradoxon does not consider the case that they are "a bit" ahead. Able to travel and explore, but not so far ahead that they had time to populate every rock they can breath on.

You are talking about UFO sightings, which is not the same thing as aliens travelling interstellar distances. UFO lore makes a strong connection between the two, but in reality, those two are separate issues.

If we talk about UFO sightings, there are several credible cases with multiple witnesses and recorded instrument data.
Belgian triangle wave, Japan Airlines flight 1628, Finnair flight AY 915, and so on.

Of course those are most likely some military technology/incidents that has never been made public by any military forces in the world.


That wasn't the question. We may not be the most intelligent thing on this planet, but that's almost impossible to measure because things with bigger brains, like dolphins, couldn't physically do the things that we do, like travel in space.

Also, I was referring to this galaxy alone, and the theory about populating the galaxy in a very short (cosmic) timeframe.

There can be some super intelligent beings 300 galaxies further away from us, but it would be even less probable that those beings would ever get here. Even if they started some massive space program, there would be those other 299 galaxies between us, so it's unlikely that they would ever get here. And that is assuming that out of all directions they would start expanding towards our galaxy, and not other galaxies.

If life is as plentiful as, for instance, the Drake equation speculates, then there should be thousands or millions of intelligent civilizations in this galaxy alone.
If such numbers were even remotely true, we would be seeing at least subjects to speculation all the time, but we don't. The only thing we have so far is the "Wow signal", which most likely was an unexplained instrumentation malfunction.


True, but whether they don't exist, or they are just simply too lazy to travel is irrelevant, as the original question was, are they here. In both cases, they would not be here.

And again, if there's any truth to that Drake stuff, there should be at least some signs of alien civilizations some place. Even if 99% of them would never leave their planet, or send out any intentional or unintentional signal, just that remaining 1% would be enough to prove their existence.

Because no such proof exists, even though based on many theories it should, it creates the said paradox.
And the argument of us being the only moderately intelligent beings, at least in this galaxy, becomes more probable.

We could go further into the discussion about how each and every theory about extraterrestrial life has turned out to be false so far. Some thought there was life on the Moon, there wasn't. Some thought there were channels on Mars, there weren't. Some thought Venus was a blue planet with water and life, it isn't. Some thought there were habitable moons in the outer solar system, there aren't. Some thought aliens might be broadcasting radio signals from exoplanets, so far they haven't.

So every time some speculative source of life has been scientifically studied, it has turned out to be untrue. And that has pushed our current hopes for finding life even more speculative, like believing that ʻOumuamua was an artificially constructed object.

No to alien visitations, because:

1. I find it implausible that they'd visit the earth secretly, and even if they tried to do it secretly, that we wouldn't have noticed it anyway and know of their presence (besides the "UFO sightings").

When e.g. Columbus visited America, the natives certainly noticed, even though Columbus used his super-secret cloaking technology on his fleet.

2. I tend to think they are bound by the same laws of physics as we are, so they still can't travel one million light years in six months or anything like that.

Having said that, I find it probable that there are some forms of life somewhere else in the universe, or at least has been millions or billions of years ago, or will be millions or billions of years from now when we are long gone. Or at least you are, I plan to remain.

Maybe they don't need space travel (as we know it). Imagine asking a caveman how he thinks humans will travel in the far future.

I've theorized on this before, and some of it discards human centrist hubris: we are not important enough for visiting extraterrestrials to play with or fear. It also involved disregarding laws of physics, and what we believe life is. If they are visiting Earth, perhaps the Earth itself ifs the entity they are coming to see, and it talks to them; we are nothing more than an annoying parasite, a flea infestation. And these beings may have FTL travel, and phase shift through physical objects at will. So passing through the physical world without impeding their path more like ghosts than little green space men. I think back to Douglas Adams describing the Hoovooloo as a hyper intelligent shade of blue. I think that could be closer to some alien life than most contemporary thoughts on the matter.

I don't necessarily believe in Alien life on Earth, but I do believe that they are out there.

Maybe they just want to talk to the whales.

Do you believe in alien visitation?

Nope.
Sure, there have been some interesting reads available when I was a kid (namely: the Dendera light bulb and the Baghdad battery), that had me believe in aliens for some time (=until I started to develop a more inquiring mind), and I was always mystified by the existence of the Nazca lines, but for several decades already, I don't believe in aliens visiting earth anymore.

Don't get my started on the tales of "alien abductions for the sake of anal probings" that for some reason are so widely spread amongst a certain demographic on this planet...

You have piqued my interest. Please tell me more about these demons.

Oops!, misread the topic title. Thought it said 'Alien Violation' ?. Never mind...

I think the earth never had an alien visitation. But the existence of life in the niverse is a very strong probability. Accepted by a scientific consensus, maybe not thecent per cent but a majority.
And I assume the Fermi Paradox it involves. But the Relativism and the quantum physics do not fit perfectly and it is a paradox as well. Because both are accurate mathematical repressentations of our perception of the known universe. They work but they do not fit.
The problem and hipothesis of the dark matter etc...

Maybe it is a matter of fine tunning, ask the exact question. And matter of time, so I relativize the paradox involved.

I did read in the past some "solutions" to the Fermi paradox. But all of them have their problems as well. In the end the solution to the problem would be a mix o all of them, or any of them.




-They exist and they were here, but not the humanity or any species. The problem is the lack of accurate paleoevidence, the lack of traces.

-They exist, but they do not talk with us. Something like the so called First Directive or maybe they are interested only in the Ficus, and they are just here because of that amazing plant.

-They exists and they are taking to us but we are unable to hear and/or understand them. Or we are not aware of them. Or they talk in an encripted way with encripted signals of some sort and we do not recognize them.

-They vanished long time ago

-They are us or they don't exist yet.

-They never existed

-They are intelligent but not evolved enough. Like us

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