[ExI] Fermi Paradox and GRB bursts

[Anders Sandberg]

Yes, I have read the paper and still remain unconvinced. Destroy the ozone layer and the land biosphere is in trouble. But do you really think that will wipe out fish all the way to the bottom of the Marianas trench? Their conclusion is not compatible with other papers on GRB damage I have read. 

Anders Sandberg, Future of Humanity Institute Philosophy Faculty of Oxford University


BillK <pharos at gmail.com> , 2/10/2014 12:25 AM:
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: 
<http://arxiv.org/pdf/1409.2506v1> 
 
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 
planets. 
 
BillK 
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