The concept of complex Dirichlet forms epsilon(c) resp. operators L-c in co
mplex weighted L-2-spaces is introduced. Perturbations of classical Dirichl
et forms by forms associated with complex first-order differential operator
s provide examples of complex Dirichlet forms.
Complex Dirichlet operators L-c are unitarily equivalent with (a family of)
Schrodinger operators with electromagnetic potentials.
To epsilon(c) there is associated a pair of real-valued non symmetric Diric
hlet forms on the corresponding real weighted L-2-spaces, which in turn are
associated with (non-symmetric) diffusion processes.
Results by Stannat on non symmetric Dirichlet forms and their perturbations
can be used for discussing the essential self-adjointness of L-c.
New closability criteria for (perturbation of) non symmetric Dirichlet form
s are obtained.