They say if aliens are going to exist, they should exist already and maybe have contacted us.
But the universe is young... why should we assume aliens would already exist let alone have contacted us? I don't see why they call it a paradox.
Why is the Fermi paradox considered a paradox?
Posts
Total:
16
-->
@n8nrgim
They may have nuked themselves early on and if they sent out radio signals, then too few and far between for us to capture them, at least to date.
.."
Jill Tarter, co-founder of the SETI Institute in California, says we haven’t listened for long enough or looked hard enough to make any such sweeping statements yet. Astronomers have studied all kinds of electromagnetic radiation – light, radio waves, gamma rays – looking for signals. Such a search has to cover all directions and distances in space, plus the different ways a signal might manifest itself, such as shifts in polarisation, frequency, modulation and intensity. Tarter sees these parameters as a multi-dimensional ocean. “When SETI turned 50, we had explored one glass of water from that ocean."...
Paradox just means something which is harder to explain.
Its very hard to explain the movement paradox, but we can move so there is obviously an explanation for how we move.
Each move can be divided on smaller moves, and so on to infinity, making it "impossible" to perform a move that has endless moves.
There are infinite amount of numbers between 1 and 2, so going from 1 to 2 is "impossible".
Yet it is possible to move.
People often confuse paradox with contradiction, but the two are not same.
Paradox is just something which assumes contradiction where there doesnt have to be one.
-->
@n8nrgim
A paradox is a named contradiction.But the universe is young... why should we assume aliens would already exist let alone have contacted us? I don't see why they call it a paradox.
The set of premises create a contradiction, the solution to the paradox is finding which premise is false.
The universe is not young on the scale we're talking about. There has been life on Earth for a billion years. Which means all else being equal even if for some reason life-capable worlds were all created at the exact same time as earth (big if) then we would expect a gausian distribution of the time it takes to become technological and cognizant.
If 1 billion years is the center and we take a reasonable earliest point at 500 million years then there should be an enormous number of civilizations (around 1/4 of the total that will ever develop) by 250 million years ago.
Now Earth being nearly the first is a solution to the paradox, it's simply a much larger coincidence than most people are comfortable with. Claiming that is about as likely as claiming that only 1/50 galaxies ever develop civilization and so the universe expands too fast for Von-neumann probes to find other civilizations (another solution).
I think Fermi's Paradox overestimates the desire/ability to make contact in a form that we could detect, especially considering the great distances involved, and the great diversity it could entail. Different intelligent species will communicate differently, they will have different values and motivations, we shouldn't just assume that at some point in their development they are motivated to communicate, or explore, and even if they do, there is no reason to assume it would be in a form we could detect. We don't even know if other intelligent life forms would necessarily be carbon based, they could be silicon based, they could be microscopic compared to us, there can be a million imaginable differences which might provide a barrier to communication, and a billion differences we can't imagine.
Plus ,there's ebuc and Best.Korea to consider, there's no fucking way either one of them is from this planet :)
they could be silicon based
Somehow silicon means different definition of communication?
How is a 15 billion year old universe young?
And honestly the radio signal thing is just a small piece of the problem. The real question is this:
Maximizing the longevity of your species means maximizing available energy. That would mean hopping from star to star and either turning them into Dyson Spheres or "turning them off" so you can convert them to Dyson Spheres at some future point and their heat isn't jettisoned into the far reaches of space. This is the rational course of action to take for any species anywhere in the Universe, assuming they hold to the human value of surviving.
And so, why do we receive light purported to be from millions or billions of light years away, if there exist aliens both self-interested and sufficiently advanced?
-->
@Swagnarok
Maximizing the longevity of your species means maximizing available energy. That would mean hopping from star to star and either turning them into Dyson Spheres or "turning them off" so you can convert them to Dyson Spheres at some future point and their heat isn't jettisoned into the far reaches of space.
That hasn't been a problem for the past 10 billion years. I mean if you have a red dwarf you could have stayed there the whole time, or if you like G type stars you would have switched once.
There are a lot of assumptions in what you just said. A Dyson sphere? Why are they trying to move planets? All they need to do is control their population and they can stay on planets or reasonable sized space habitats.
No, the problem is that the idea of a billion year old civilization boggles the mind. Anything that could ever be thought of or tried would have been a thousand times over.
So either they did something to kill themselves (which is a lot harder than people make it out to be) or they must have built self-replicating drones and sent them out into the universe.
It's not radio silence that is paradoxical, it's the lack of probes. Even if they were from civilizations ten thousand lightyears away (and thus all but unreachable without scifi stuff) their probes should be here if they existed at our technological level for more than a millennium.
assuming they hold to the human value of surviving.
If there is anything we can assume about life it's that surviving is the root value.
-->
@n8nrgim
Why is the Fermi paradox considered a paradox?
Because it fits with all the necessary requirements.
All together:
- The universe is about 14 billion years old.
- The Known (observable) universe is 93 billion light years in diameter. We don’t actually know the true size of the universe. It could be meany magnitudes larger.
- Within the known universe it is estimated there are about 200-billion galaxies, several hundred-billion-trillion stars, and sextillions of planets. These numbers are on the conservative side in my opinion.
- Simple life on Earth has existed for over 3 billion years, modern humans have existed for about 300,000 years, Human civilisation has been around for about 6000 years, humans went from the steam engine to the rocket engine within 200 years.
-->
@Reece101
Staggering statistics for the staggerable.
Of course, some folk suggest that an extra-universal guy knocked it all together less than 10,000 years ago.
Whichever.
Makes you wonder where all the stuff came from though.
Maybe from an infinite DIY retail outlet.
Universal matter, in the green bags, on the shelf next to the tile grout.
Dread to think how much it cost.
Single blokes and their hobbies hey.
And Mr Fermi got a paradox named after him.
For stating the obvious.
the universe should last for trillions of years is my point. plus if life developed somewhere, we cant necessarily know. we can't even see planets in other galaxies, i dont think. (unless james webb telescope changed that). thirteen billion years is enough time for life to form, but we shouldn't assume it's adequate that there 'must' be other life forms out there, i would think. give it a quarter billion years and get back with us, i say.
i think the only point that answers this, is that it's not so much a contradiction, the paradox, as something hard to understand.
" give it a quarter billion years"
i meant a quarter trillion.
-->
@n8nrgim
the universe should last for trillions of years is my point.
That's got nothing to do with it.
Why would how long the universe would last (before heat death I presume) affect how many technical civilizations that develop?
On the timescales we've observed for the development of life, intelligence, and technology it would be an unfathomable coincidence if the technological explosion on two different worlds within 100 light years of each other occurred within 100,000 years of each other.
If you're saying "The universe is young so we shouldn't expect contact for billions of years yet" that's the same as saying "we're first, cool", but that would be quite a coincidence wouldn't it?
Somebody has to be first, but that's not a likely assumption compared to the other solutions to the paradox.
plus if life developed somewhere, we cant necessarily know.
That was the assumption before this was explored at the time the paradox was introduced. The reason that seemed to be a safe assumption was because it was hard to imagine that computer technology would be as powerful and accessible as it has turned out to be.
As of this moment it is obvious that self-replicating probes are plausible. That changed the significance of distance. A million year journey is unrealistic for biological travelers (or machines that can't fix themselves), a signal traveling a hundred thousand light-years doesn't make any sense; but a system of probes designed to contact all life in the galaxy shouldn't take more than a million years to do it.
If no one else has done it, we'll do it in the next 100,000 years; which is (again) on geological and stellar timescales a blink of an eye.
we can't even see planets in other galaxies, i dont think.
We can't see individual stars in other galaxies *unless they're exploding or something*
We can't see planets of our nearest neighbors in the conventional sense. Everything we know about exo-planets has been impressive deduction from the slightest wobbles and the faintest rays of light.
Again, that's the outdated model of contact "Alien sees us, alien sends radio signal" That's easy to explain away. The contact strategy that is not easy is this: "Alien doesn't see life, decides to tell the entire galaxy about themselves even if it takes a million years."
thirteen billion years is enough time for life to form, but we shouldn't assume it's adequate that there 'must' be other life forms out there
It's never a "must", it just requires that Earth be incredibly exceptional in ways many people find uncomfortable.
Exceptional in developing technical civilization the fastest. Exceptional in developing life at all. That sort of thing.
There is no intelligent life anywhere in the Universe except on this planet.