Free-energy fluctuations and chaos in the Sherrington-Kirkpatrick model

The sample-to-sample fluctuations Delta FN of the free-energy in the Sherrington-Kirkpatrick model are shown rigorously to be related to bond chaos. Via this connection, the fluctuations become analytically accessible by replica methods. The replica calculation for bond chaos shows that the exponent mu governing the growth of the fluctuations with system size N, Delta FN approximately Nmu, is bounded by mu< or =1/4.