On Noether's and Weyl's bound in positive characteristic
In this note we generalize several well known results concerning
invariants of finite groups from characteristic zero to positive
characteristic not dividing the group order. The first is Schmid's
relative version of Noether's theorem. That theorem compares the
degrees of generators of a group with those of a subgroup. Then we
prove a suitable positive characteristic version of Weyl's theorem on
vector invariants: polarization works in small degrees. Using that we
show that the regular representation has the "most general" ring of
invariants, thereby generalizing theorems of Schmid and Smith.
Appeared in: Invariant Theory in All Characteristics.
E. Campbell, D. Wehlau, eds., CRM Proceedings & Lecture Notes
35 (2004) AMS: Providence, RI, 16 pages
Available files:
Back to index
Last updated: July 15, 2004