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The Fermi paradox revisited: Technosignatures and the contact era

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Re: The Fermi paradox revisited: Technosignatures and the contact era

#241

Post by withinboredom »

thehappypm wrote: post #209
twawaaay wrote: post #154

Earlier quoted context omitted.

We've been able to fly or emit radio signals only for a bit more than 100 years. If there exist any other civilisations and we assume they start independently, there should be ones that started billions of years ago. Which is enough to visit entire galaxy even at very slow speeds. The paradox is that we are not seeing any signs of any other intelligent life.

If they visited us a billion years ago, would we know? Time is as big as space. If you’re positing that aliens must exist and can explore, they might have just done that and lost interest a million years ago, or they do sweeps every hundred thousand years.

Plot twist: dinosaurs were really an alien species. After they were wiped out by an asteroid slung at the earth by an evil prince, the earth was written off as a memorial site.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#242

Post by pfdietz »

thehappypm wrote: post #218
superposeur wrote: post #138

Earlier quoted context omitted.

Yes, these are alternative explanations. The explanation that is surprisingly undermentioned is the one I put forward: there is no life.

How do you explain it happening exactly once? If it’s vanishingly unlikely, but space is incomprehensibly huge and time is vastly long, then it happening exactly once is extremely improbable. 0 times, believable. But those probabilities yielding 1 life event must mean 2 life events is also possible, no? Or 3? Or 100? Why so confident it’s exactly 1?

All that's required to explain the Fermi Paradox is that it happen < 1 in an observable volume of the universe. The volume of the universe in which OoL could happen could be vastly larger, but we could never see most of it. Each extremely rare occurrence of intelligent life would never be able to contact any other, as they'd never be causally connected by signals traveling at the speed of light.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#243

Post by pfdietz »

friend_and_foe wrote: post #190
georgeg23 wrote: post #147

Earlier quoted context omitted.

The biggest recurring mistake that humans have made throughout history is to think themselves special and unique. The heavens don't orbit the Earth.

How is this the biggest mistake? So far it does appear to be the case. What negative consequences have come of believing ourselves to be unique? We have yet to find, on our planet or elsewhere, any creatures that build complex systems out of dead things.

He's engaging in a kind of ad hominem argument, that believing we are unique is a morally questionable position, therefore we must believe otherwise.

The errors in history have been the opposite: believing other intelligences are more common than they have turned out to be. The world was filled with non-human creatures in mythology and folklore. In the 1700s it was presumed every planet in the solar system had intelligent life on it.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#244

Post by withinboredom »

alfiedotwtf wrote: post #213
credit_guy wrote: post #149

The Fermi paradox is good for a nice chat at a party. But it's not a paradox at all. Imagine there's an alien civilization in our galactic neighbor Proxima Centauri. How would we know they are there? To make it more plausible. Let's say we figure out a way to send a space probe to Proxima Centauri. How do we communicate with that probe? Easy, you say, just like we communicate with the Voyagers: they point a reasonabl…

Flip the point of view for a moment - what's the absolute best way we could try to say "hey, we're here" to the universe in the hope of detection from far away civilizations? I like the idea of Contact's Prime Number signal but how would you do this on a large scale? I was thinking Dyson Sphere a star as a huge Flag Semaphore to send the message, but then what rate do you flip bits to make it optimal for the receivin…

And what if we broadcast and whomever hears us wants us dead? Maybe it’s so quiet because to be loud results in death of the entire civilization.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#245

Post by robocat »

credit_guy wrote: post #149

The Fermi paradox is good for a nice chat at a party. But it's not a paradox at all. Imagine there's an alien civilization in our galactic neighbor Proxima Centauri. How would we know they are there? To make it more plausible. Let's say we figure out a way to send a space probe to Proxima Centauri. How do we communicate with that probe? Easy, you say, just like we communicate with the Voyagers: they point a reasonabl…

> it's just some aliens that are not pointing an antenna straight at us

Even worse, don’t modern digital signals look similar to noise, are usually encrypted, use much higher frequencies, and have less gap between bands? Good luck trying to spot a cellphone signal from Proxima Centauri (my phone has trouble getting signal at home!)

Many analogue broadcast signals have been replaced by digital, and broadcast as a technology is in its twilight years (although my parents do still get TV and listen to the radio!)

So signals might only be detectable in nascient technology civilisations - they then move on to undetectable signals?

Re: The Fermi paradox revisited: Technosignatures and the contact era

#246

Post by lapcat »

friend_and_foe wrote: post #235
lapcat wrote: post #48

Earlier quoted context omitted.

> Above statements are proving my point. I don't really see how. > human civilization is stronger than ever I don't really see how. > on the verge of expanding beyond the home planet I don't really see how.

Really? You don't see how our civilization is stronger than it's ever been? You don't see how we are on the verge of expanding beyond our home planet? Just, don't see it huh? Perhaps you're not the person that should be explaining to everyone what is painfully obvious and what is not then.

> Perhaps you're not the person that should be explaining to everyone what is painfully obvious and what is not then.

You didn't even understand my comment. I meant it's painfully obvious to me. It should have been obvious that I didn't mean it was obvious to everyone, but obviously some people can't see the obvious.

I could write a long essay on why we're not on the verge of expanding beyond our home planet, but I feel that it would be a big waste of time. I'm not going to change your mind, you're not going to change my mind, and that's one reason why humanity is ultimately doomed.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#247

Post by AlbertCory »

booleandilemma wrote: post #238
pfdietz wrote: post #228

Earlier quoted context omitted.

No, he was rightly pointing out that your "there probably is" statement was bullshit, not supportable from the evidence.

I think AlbertCory was saying that to assign specific probabilities, as the Drake equation does, is BS. To say "there's probably life out there", in a vague, speculative sense of probably, is a different sort of thing.

Thanks, right.

It's like saying "the probability of a market crash is 0.01."

There is no number you can put on it.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#248

Post by pfdietz »

troyvit wrote: post #129
superposeur wrote: post #102

In my opinion, the excitement occasioned by the discovery of so many exoplanets has clouded our collective judgement on the Fermi Paradox, leading the overwhelmingly most probable resolution to be underemphasized. Namely: there is no life out there. Not due to baroque mechanisms such as techno-self-destruction but just due to its sheer unlikeliness. As large as the number of stars in the observable universe is (let’s…

How would your perception change if life was discovered on the moons around Saturn and Jupiter? Does that increase the likelihood of life outside our system?

If it was biologically similar to Earth life, it wouldn't prove much of anything, as it could have gotten there by impact panspermia.

Discovery of a fundamentally different biology, even on Earth, would indicate two OoL events had occurred near each other. This would be very strong evidence that OoL cannot be rare.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#249

Post by yyyk »

credit_guy wrote: post #149

The Fermi paradox is good for a nice chat at a party. But it's not a paradox at all. Imagine there's an alien civilization in our galactic neighbor Proxima Centauri. How would we know they are there? To make it more plausible. Let's say we figure out a way to send a space probe to Proxima Centauri. How do we communicate with that probe? Easy, you say, just like we communicate with the Voyagers: they point a reasonabl…

>The only question is not why we didn't "see" any aliens so far. It's why we wasted so much money on SETI. Was Carl Sagan not able to do the back of the envelope calculation I just did here?

Sagan was perfectly capable of doing these calculations. However, SETI was a nice way to divert funds to radioastronomy.

Not the first time Sagan was 'creative' - per his Nuclear Winter model, if sometimes lights a match in the poles the entire planet will burn.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#250

Post by yreg »

chrononaut wrote: post #240
jjoonathan wrote: post #210

Earlier quoted context omitted.

It routinely bothers me a bit that, IME, most IRL discussions of the Fermi Paradox settle on this rather simple explanation when the whole idea was that this "simple explanation" was extremely unlikely, pushing speculation to more complicated and interesting hypotheses. Emergence of life on Earth took 13.7 billion years, galactic colonization should only take millions of years. We should not expect to find the galaxy…

> Emergence of life on Earth took 13.7 billion years 13.7 billion years? Isn't that the age of the universe, and didn't life emerge on Earth only after about a billion years?

Yes, but the parent means we are 13.7B years late to the party. Other civs should have been spawned before Earth was formed.
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