* Andrew Farmer:Especially considering that there aren't enough atoms in the universe to
store all that precalculated data, nor enough energy to do all the
calculations.
Typically, such estimates ignore the possibilities of quantum superpositions.
(Schneier says that there's enough energy in a supernova to do about 2^224 operations on a 100% efficient computer. And remember that AES or PGP take multiple operations to calculate results...)
Schneier's estimates are wrong. They are based on the incorrect assumption that all bit operations are irreversible and entropy-increasing. There is no hard evidence that this is true in general.
Attachment:
PGP.sig
Description: This is a digitally signed message part