Trevor Arnold
Introduction to characteristic p methods in complex geometry
We attempt to sketch a general philosophy for reducing
questions about complex varieties to varieties over finite fields. This
method first involves finding a ``model'' for the complex situation over
some finitely-generated Z-algebra A. Characteristic p results can then
be applied to the fibers over the closed points of A. The second step is
then to show that properties of these fibers are inherited by the
generic fiber, thereby proving something about the original setup.