Re: Possible solution to Fermi's Paradox?

Eliezer S. Yudkowsky (
Wed, 03 Mar 1999 22:42:24 -0600

$public cheer =Changed my opinion

Robin Hanson wrote:
> James Annis' article, "An Astrophysical Explanation for the
> `Great Silence'" JBIS 52:19-22 1999, is thoughtful and interesting.
> Gamma ray bursts do seem a plausible component of the total
> "great filter" that stands between dead matter and expanding
> lasting life. Some critiques, however:
> 1) It's a relatively weak effect.
> But clearly if life appeared quickly in most every system,
> and if civilizations expanded at .1c, then most of the
> universe would now be colonized if gamma ray bursts were the
> only problem. (A simulation could be constructed if anyone
> doubts this.) Thus this can't be the whole filter. So how
> much of the filter can it be?

Oh, well. I thought, for a brief, pleasant moment, that GRBs might be good enough to explain the Great Filter Paradox, if they were energetic enough to wipe out all life in a galaxy

One speculation was that galaxies were wiped clean every so often by Singularities escaping our Universe through macrocosmic energy events. This would explain why there weren't any mortals left behind by an escaped Singularity, although it still wouldn't explain why, if a Singularity escaping is a good thing, the Singularity didn't leave behind autonomous robots to keep up the good work.

As it is, given that at least one in a thousand mortal races would be disciplined enough to avoid a Singularity entirely - hiveminds and the like - and spread with Slow Zone tech across the galaxies, I can only assume that the first Singularity to notice their radio emissions grabs them and leaves. This would seem to bode well for us, as the simplest explanation would seem to be altruistic (Compact?) motives.

But then why haven't we been contacted by our local self-reproducing Observer nanobot? Or if races are "cleaned up" and exterminated, why haven't we been destroyed? And if the Powers don't interfere at all, why aren't the mortal remnants developing normally?

  1. Mortal races would spread through the galaxies unless prevented by Powers.
  2. If the Powers have any goals in this Universe, why don't they expand their sphere of influence at lightspeed?

As far as I can tell, there is absolutely no set of assumptions that leads to the Great Silence. Life is not only absurd but impossible. It may be time to start thinking about this world being a computer simulation.

> A civilization that uses the bulk of a galaxy's starlight for
> its own power requirements is a remarkably obvious entity.
> This is because galaxies naturally obey scaling laws between
> the surface brightness, the radius of the stellar distribution
> and the thermal velocities of the stars. The latter two
> quantities reflect the mass and its resulting gravitational
> potential, while the formal is the result of this same mass
> emitting light as stars. If civilization takes that light
> for its own purposes, the scaling laws are broken and the
> galaxy becomes an outlier on plots showing the scaling laws.
> For a sample of 137 galaxies, no such outliers are found.

Wonderful. So even the Zoo Hypothesis gets trashed.

--         Eliezer S. Yudkowsky

Disclaimer:  Unless otherwise specified, I'm not telling you
everything I think I know.