[ExI] The Great Silence again

[Eugen Leitl]

On Tue, Apr 26, 2011 at 01:35:48PM -0500, Damien Broderick wrote:

> Are you absolutely sure? Galaxies are surrounded by annuli of invisible  

You can only get lower bounds, but http://home.fnal.gov/~carrigan/infrared_astronomy/Fermilab_search.htm

> mass, and there are vast voids between clumps of galaxies. Not making  

Expansion will be creating spherical voids, expanding at relativistic
speeds. Time for visible dimming and spectral shift would be years to
decades for the average system. If smart life is not rare then there's
enough metallicity in early systems to give them lead times of several
gigayears. The only reason you fail to observe them is for the
same reason you will fail to observe the Tsar Bomba fireball.

> any superstitious, glib claims here, but it might not be *impossible*  
> that radiating hyperintelligent cultures would leave such footprints.  

Inoculated cultures grow always spherically.

Occam sez: I will cut you.

-- 
Eugen* Leitl <a href="http://leitl.org">leitl</a> http://leitl.org
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