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Grabby Aliens (2021)

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Re: Grabby Aliens (2021)

#141

Post by cwillu »

FrustratedMonky wrote: post #112
cwillu wrote: post #67

Earlier quoted context omitted.

Alas, there's a fifth possibility: 5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone.

I think the assumption is that 'transportation' between stars will be solved by sufficiently advanced aliens/us. BUT, that this will be one of those very difficult tasks, so it will take many thousands or millions of years. And so goes towards 'we are early'. So, if we are grabby, and all the other grabby aliens, are all still getting over this transportation hump.

The universe isn't a rock concert, “we're here too early” is not the only possible reason why there's no band on the stage.

Re: Grabby Aliens (2021)

#142

Post by throwuwu »

XorNot wrote: post #73
cwillu wrote: post #67

Earlier quoted context omitted.

Alas, there's a fifth possibility: 5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone.

That itself would be quite interesting though, because based on what we know now it's merely difficult, not impossible with reasonably foreseeable technological improvements. The dynamics which would make it impossible on any known timespan don't seem currently observable.

If you assume FTL travel will never be developed then distance and time are simple limiting factors. How do you keep a cohesive civilization going when communication takes 200 years? Or even just 20? Here on Earth entirely new languages and cultures arose across distances that wouldn’t even cross a state line when communication was limited to a small handful of travellers and merchants. Any colony further away than 5ly would quickly diverge. I’m pulling that number out of my hat but I’m sure you could figure out the effect of time spent in journey on willingness to travel. Not many people would commit significant chunks of their lives to interstellar business trips. Radio communications won’t solve it either since they’d be out of date and essentially one way if it took decades to get a response. No I think any interstellar colonization effort would immediately create competing civilizations distinct from their homeworld.

Re: Grabby Aliens (2021)

#143

Post by FrustratedMonky »

cwillu wrote: post #141
FrustratedMonky wrote: post #112

Earlier quoted context omitted.

I think the assumption is that 'transportation' between stars will be solved by sufficiently advanced aliens/us. BUT, that this will be one of those very difficult tasks, so it will take many thousands or millions of years. And so goes towards 'we are early'. So, if we are grabby, and all the other grabby aliens, are all still getting over this transportation hump.

The universe isn't a rock concert, “we're here too early” is not the only possible reason why there's no band on the stage.

? Did you read the original post? On grabby aliens?

This whole discussion is about being 'early'.

Not sure you are making a point.

Edit: The original post discusses below light speed transportation. 25% speed of light is used in the estimates.

But guess I agree, if no aliens including us, never-ever with infinite time ever develop transportation that can get up to some fraction of light speed. Then maybe no colonization ever happens, and the grabby guys stay in their system.

Re: Grabby Aliens (2021)

#144

Post by throwuwu »

whizzter wrote: post #95
XorNot wrote: post #73

Earlier quoted context omitted.

That itself would be quite interesting though, because based on what we know now it's merely difficult, not impossible with reasonably foreseeable technological improvements. The dynamics which would make it impossible on any known timespan don't seem currently observable.

I think a huge factor you don't account for here is that some of these technological improvements might imply a great-filter that we really haven't passed yet as humans, and the negative effects would affect most similarly expansionist and competitive races alike us since it might be questionable if there would be enough pressure on a non-competitive race to expand rather than just conserve local resources. Just with…

You might want to check the physics on your assertion that a starship could take out a city. It’d have to be designed to do so otherwise it would just vaporize as it entered the atmosphere at the velocity you’d need for that kind of impact.

Re: Grabby Aliens (2021)

#145

Post by iraqmtpizza »

LadyCailin wrote: post #103
iraqmtpizza wrote: post #91

Earlier quoted context omitted.

All evidence says that humans stand alone in the galaxy. Everything else is cope.

That’s like looking only in the drawer, and saying, there is no evidence here that a cat lives in this house. When in fact the cat is just upstairs.

There are electromagnetic waves reaching the earth from this galaxy which were emitted anywhere from 80,000 years ago to an instant ago, and everywhen in between. Practically all alien races among the hundreds of billions of solar systems would have to have been electromagnetically silent for a minimum of 80 thousand years for us not to see them.

If you include other galaxies, then they would've had to have been silent since the beginning of time.

Also, non-living matter spontaneously forms into living matter by no known mechanism.

If you're going to believe something religiously, make it something less trivial than muh aliens.

Re: Grabby Aliens (2021)

#146

Post by shrimp_emoji »

fouc wrote: post #2

What I found most interesting about this model was the implication that humans are possibly one of the earliest sentient spacefaring species to have appeared so far. Which explains why we haven't seen any other signs of extraterrestrial intelligence yet.

Our ability to detect signs of ETI is very limited. It could be all over, and we could have even detected it already, but we don't realize it. Studying up on astrophysics (how we detect and transmit signals, how signals attenuate and fade over cosmic distances, and some of the signals SETI has already received) reveals that.

The Fermi paradox is only a paradox due to the assumption that in a few million years a civilization will colonize the entire Milky Way just because it's theoretically possible, so we should be up to our eyeballs with aliens' von Neumann probes. But many things are theoretically possible. We could build the world's largest house -- the size of Nebraska. Every nation could reorient and sink their economy into that megaproject and do it. But it's irrational to; there's better things we want to do with our resources (which will always be finite, all the way up the Kardashev scale). That's why I think it's silly to expect any intelligent life to be that ambitious (or competent).

Re: Grabby Aliens (2021)

#147

Post by throwuwu »

throwawayqqq11 wrote: post #53
Matt_Mahgerfteh wrote: post #35

Earlier quoted context omitted.

Yeah, it's like we're playing cosmic detective trying to figure out if there's anyone else out there in the universe. The fact that we haven't seen any clear signs of alien civilizations doing their thing is kind of mind-boggling. It's like, are they just really subtle about it, or are we just super early to the party?

When you mine asteroids in orbit on a large scale around your star, the released dust/debris would form an IR halo around the star that would be very easy to detect and reveal your presence but we dont see any of it. So, early humans it propably is.

I don’t think we’re going to build rock crushers in space. With all that available energy it’d make more sense to just throw the whole rock into a smelter and fractionate the elements as they boil off. Why waste the slag either? You need all the material you can get so hang on to it and use it as ballast or extract the carbon and silicon from it. It’s more likely that we don’t see waste because there isn’t any, a dollar saved is a dollar earned.

Re: Grabby Aliens (2021)

#148

Post by bhickey »

bhickey wrote: post #52
AnimalMuppet wrote: post #41

Earlier quoted context omitted.

Aliens collecting all the light/electromagnetic radiation from stars would be an interesting way to get dark matter. That's one place it could fit. And, if our theories are right, we're at 4.9% regular matter and 26.8% dark matter, so dark matter is five times as much as regular matter, so that's a lot of aliens...

What you're suggesting doesn't make sense. Dark matter isn't non-luminous matter. It's matter that only interacts gravitationally, but not electromagnetically. This means it doesn't undergo collisions and can't shed angular momentum. It forms a diffuse, largely uniform cloud throughout galaxies. The result is that galaxies are more dense further from the galactic core than we would predict from luminous matter alone.

> Dark matter isn't non-luminous matter.

What I meant to write is—

> Dark matter isn't merely non-luminous matter.

Re: Grabby Aliens (2021)

#149

Post by [deleted] »

jojohohanon wrote: post #134

Why are we now? https://www.ox.ac.uk/news/science-blog/why-are-we-now It’s early here, but it think the gist of it is using Bayes to quantify: Given that the universe would seem to get more hospitable at older ages, why are we alive now? IIUC the most likely explanation is some secondary force ( aliens ) to modify the future hospitality.

[deleted]

Re: Grabby Aliens (2021)

#150

Post by shrimp_emoji »

yreg wrote: post #115
cwillu wrote: post #67

Earlier quoted context omitted.

Alas, there's a fifth possibility: 5. Controlled transportation between the stars, sufficient for colonization, is sufficiently impractical that there are no grabby aliens within our light-cone.

Even if interstellar travel is impractical, an advanced expansionist civ would be interested in building megastructures. And since there is no stealth in space (unless you can somehow mask heat), they should be observable. Ofc there are explanations for that part of the paradox as well, but the impractical travel theory doesn't cover it.

You're implying we'd easily see megastructures. Believe it or not, there's many more stars we haven't inspected than have. And our telescopes suck too much to see all but the largest megastructures, which you're assuming it would make rational sense to build in the first place. There can be better things for an economy to spend its (always finite) resources on.
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