  The existence of small amounts of advanced radiation, or a tilt in the arrow
of time, makes the basic equations of physics mixed-type functional
differential equations. The novel features of such equations point to a
microphysical structure of time. This corresponds to a change of logic at the
microphysical level. We show that the resulting logic is a quantum logic. This
provides a natural and rigorous explanation of quantum interference. This
structured-time interpretation of quantum mechanics is briefly compared with
various other interpretations of q.m.
