(Forward and backward
generators) Let
be a Markov process in
and
are the associated propagators. We define the backward and forward
"generators"
and
as follows:
1.
,
(Backward Kolmogorov generator)
.
2.
,
(Forward Kolmogorov generator) .
A function
is included in the domain
of
if the limit 1 exists.
A measure
is included in the domain
of
if the limit 2 exists.
Proposition
(Kolmogorov equations in general setting).
Let
be a Markov process in
and
is the associated transition function. For any
,
and
we have