  An encyclopedia article on mathematical aspects of quantum field theory in
curved spacetime. Section titles are: Introduction and preliminaries;
Construction of *-algebra for a real linear scalar field on globally hyperbolic
spacetimes and some general theorems; Particle creation and the limitations of
the particle concept; Theory of the stress-energy tensor; Hawking and Unruh
effects; Non-globally hyperbolic spacetimes and the time-machine question;
Other related topics and some warnings.
