Multiplicative invariant theory, as a research area in its own right
within the wider spectrum of invariant theory, is of relatively recent
vintage. The present text offers a coherent account of the basic results
achieved thus far..
Multiplicative invariant theory is intimately tied to integral
representations of finite groups. Therefore, the field has a
predominantly discrete, algebraic flavor. Geometry, specifically the
theory of algebraic groups, enters through Weyl groups and their root
lattices as well as via character lattices of algebraic tori.
Throughout the text, numerous explicit examples of multiplicative
invariant algebras and fields are presented, including the complete list
of all multiplicative invariant algebras for lattices of rank 2.
The book is intended for graduate and postgraduate students as well as
researchers in integral representation theory, commutative algebra and,
mostly, invariant theory.