  We elaborate on the existing notion that quantum mechanics is an emergent
phenomenon, by presenting a thermodynamical theory that is dual to quantum
mechanics. This dual theory is that of classical irreversible thermodynamics.
The linear regime of irreversibility considered here corresponds to the
semiclassical approximation in quantum mechanics. An important issue we address
is how the irreversibility of time evolution in thermodynamics is mapped onto
the quantum-mechanical side of the correspondence.
