Chaotic hypothesis: Extension of Onsager reciprocity to large fields and   the chaotic hypothesis
  The fluctuation theorem (FT), the first derived consequence of the {\it Chaotic Hypothesis} (CH) of ref. [GC1], can be considered as an extension to arbitrary forcing fields of the fluctuation dissipation theorem (FD) and the corresponding Onsager reciprocity (OR), in a class of reversible nonequilibrium statistical mechanical systems. 
Giovanni Gallavotti (Fisica, Universita' di Roma)