Derandomization techniques are used to show that at least one of the
following holds regarding the size of the counting complexity class
SPP.
1. SPP has p-measure 0.
2. PH is contained in SPP.
In other words, SPP is small by being a negligible subset of
exponential time or large by containing the entire polynomial-time
hierarchy. This addresses an open problem about the complexity of the
graph isomorphism problem: it is not weakly complete for exponential
time unless PH is contained in SPP. It is also shown that the
polynomial-time hierarchy is contained in SPP^NP if NP does not
have p-measure 0.