[ExI] Fermi Paradox and GRB bursts

BillK pharos at gmail.com
Wed Oct 1 22:21:26 UTC 2014

On Wed, Oct 1, 2014 at 10:59 PM, Anders Sandberg wrote:
> I am sceptical of their conclusion. While a GRB no doubt can cause mass
> extinctions they do not remove biospheres: a few cm of water or rock
> protects against the radiation in their paper.
> The GRB rate is also low enough that it cannot cause effective
> synchronization of advanced life a la the Annis/Cirkovic scenario.

The full paper is available as a pdf file here:

I am not a GRB expert, but their paper seems to be thorough. They
consider the different types and strengths of GRBs and the frequency
of each type, They say that the main damage is caused by the
destruction of the ozone layer. Even if the GRB only destroyed higher
lifeforms, that would be sufficient to leave only bacteria on nearby


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