[ExI] How to survive forever

[Anders Sandberg]

On 15/06/2012 17:30, Anders Sandberg wrote:
>
> The main problem is likely that temperature never gets below  
> T_min=10^-19 K due to horizon radiation, and that forces a finite 
> amount of possible computation. Still, that is M_cluster/(kT_min 
> ln(2)) irreversible computations (including error corrections) - plus 
> a large number of reversible computations.
>

Ah, forgot a factor of c^2. The right number is c^2 M_cluster/(kT_min 
ln(2)).

Using the Virgo cluster and asusming we use the dark matter too, we get 
10^15 solar masses, or about 10^45 kg. That will allow around 10^104 
computations.

A lot, although far less than Seth Lloyds estimate that the universe so 
far has performed 10^120 operations ( 
http://arxiv.org/abs/quant-ph/0110141) - but his operations seem to 
include reversible ones, which are not covered by the above estimate 
which is based on the Brillouin inequality.

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