Spontaneous reversal of irreversible processes in a many-body Hamiltonian
evolution

KTH/Nordita/SU seminar in Theoretical Physics [before December 2013]

Wednesday 05 March 2008
from 11:00
to 12:00 at
FA31
(
FA31
)

Speaker :

Francesco Calogero ( FC, Physics Department, University of Rome "La Sapienza")

Abstract :

An autonomous Hamiltonian model will be presented and discussed. It is
a modified version of the most-general translation-invariant N-body problem (N
is arbitrary, as well as the dimensions of the ambient space). It features an
arbitrary real parameter T and possesses the following two properties, whose
coexistence is clearly remarkable. First: all the solutions of this model are
completely periodic (i. e., periodic in all degrees of freedom: positions
and velocities of the N particles), with the (arbitrarily assigned) period T.
Second: the generic solution of this model (starting from generic initial data)
has a behavior that essentially coincides with that of the original (standard)
many-body problem (with arbitrary interparticle forces), for times much smaller
than T. Hence over such (finite but arbitrarily large) times the dynamics
implied by our model generally entails the standard statistical dynamics and
thermodynamics, entailing the thermodynamic irreversibility of physical
processes; yet its exact evolution is competely periodic...This is joint work
with François Leyvraz.