My guess is that the “filter” is at the point of life formation, but not in the way you describe. I am not sure we could detect an alien intelligence unless it left human-like artifacts. It would look largely “natural” to us. I’ve asked the question earlier on this forum, “how would we detect a generalized optimizer?” without relying on it leaving structures that look “artificial” to us. I have repeatedly pointed out that we don’t have a good definition of “life”, and that stars and galaxies tend to qualify under any definition that is not specifically tailored to carbon-based life forms.
So, my guess is, there is plenty of intelligent life everywhere, we just don’t recognize it as such, because it is unimaginably different from our own, and we treat it as a natural process.
IR from waste heat should cold to warm black bodies radiating a lot of heat over a large area. It should have relatively few spectral lines. It might look a bit like a brown dwarf, but the output from a normal star is huge compared to a brown dwarf, so it should look like a really huge brown dwarf, which our normal models don’t offer a natural explanation for.
I expect intelligent life to replace itself with AIs or emulations that use resources for computation as efficiently as possible. I expect it to converge regardless of how it started. In particular, stars look very wasteful of entropy. I expect intelligent life to disassemble them for later, or at least build Dyson spheres. Even if there is more computation that can be extracted from dark matter, I expect a small amount of effort devoted to ordinary matter, which would change the face of the universe over galactic time scales.
A huge swarm/sphere of solar collectors uses up precious materials (silicon, etc) that are far more valuable to use in ultimate compact reversible computers—which don’t need much energy to sustain anyway.
You seem to be bottomlining. Earlier you gave cold reversible-computing civs reasonable probability (and doubt), now you seem to treat it as an almost sure scenario for civ developement.
No I don’t see it as a sure scenario, just one that has much higher probability mass than dyson spheres. Compact, cold structures are far more likely than large hot constructions—due to speed of light and thermodynamic considerations.
My guess is that the “filter” is at the point of life formation, but not in the way you describe. I am not sure we could detect an alien intelligence unless it left human-like artifacts. It would look largely “natural” to us. I’ve asked the question earlier on this forum, “how would we detect a generalized optimizer?” without relying on it leaving structures that look “artificial” to us. I have repeatedly pointed out that we don’t have a good definition of “life”, and that stars and galaxies tend to qualify under any definition that is not specifically tailored to carbon-based life forms.
So, my guess is, there is plenty of intelligent life everywhere, we just don’t recognize it as such, because it is unimaginably different from our own, and we treat it as a natural process.
Why would you expect to not see infrared emissions from them?
A maximally efficient reversible computing arcilect (if possible) would operate close to the CMB or even below it and emit next to nothing.
You see IR and all kinds of other emissions from all kinds of sources, what would distinguish artificial from natural?
IR from waste heat should cold to warm black bodies radiating a lot of heat over a large area. It should have relatively few spectral lines. It might look a bit like a brown dwarf, but the output from a normal star is huge compared to a brown dwarf, so it should look like a really huge brown dwarf, which our normal models don’t offer a natural explanation for.
Consider that maybe existing brown dwarfs and the laws apparently governing them are the artifacts of an alien intelligence.
Or maybe dark matter are the waste left after all useful energy has been extracted from the normal matter.
Or maybe our current models of supernova explosions fail because they don’t account for the alien intelligences using them for their purposes.
How do you tell natural from artificial? What would be a generic artifact of any powerful optimizer?
I expect intelligent life to replace itself with AIs or emulations that use resources for computation as efficiently as possible. I expect it to converge regardless of how it started. In particular, stars look very wasteful of entropy. I expect intelligent life to disassemble them for later, or at least build Dyson spheres. Even if there is more computation that can be extracted from dark matter, I expect a small amount of effort devoted to ordinary matter, which would change the face of the universe over galactic time scales.
Stars are disassembling all over—mostly by exploding, but some are getting slowly sucked dry by a black hole or other compact object.
What kind of practical dissembly process do you expect future technology to use, such that it is more efficient than what we already see?
Dyson spheres suck:
they require tons of energy to build,
they are wasteful from an architecture standpoint by dispersing matter and thus increasing communication overhead (compact is better)
they are inefficient from a cooling perspective, which is key to maximizing computation (landauer’s principle)
Are you saying Dyson spheres are inefficient as computational substrate, as power collection, or both?
Because to me it looks like what you actually want is a Dyson sphere / swarm of solar collectors, powering a computer further out.
A huge swarm/sphere of solar collectors uses up precious materials (silicon, etc) that are far more valuable to use in ultimate compact reversible computers—which don’t need much energy to sustain anyway.
You seem to be bottomlining. Earlier you gave cold reversible-computing civs reasonable probability (and doubt), now you seem to treat it as an almost sure scenario for civ developement.
No I don’t see it as a sure scenario, just one that has much higher probability mass than dyson spheres. Compact, cold structures are far more likely than large hot constructions—due to speed of light and thermodynamic considerations.
I don’t expect any of that from an intelligence sufficiently dissimilar from our own.