Maciej P. Wojtkowski, Carlangelo Liverani Conformally Symplectic Dynamics and Symmetry of the Lyapunov Spectrum (40K, AMSTeX) ABSTRACT. A generalization of the Hamiltonian formalism is studied and the symmetry of the Lyapunov spectrum established for the resulting systems. The formalism is applied to the Gausssian isokinetic dynamics of interacting particles with hard core collisions and other systems.