On tilting modules for algebraic groups.
Using quantum sections of filtered rings and the associated Rees rings one can lift the scheme structure on Proj of the associated graded ring to the Proj of the Rees ring. The algebras of interest here are positively filtered rings having a non-commutative regular quadratic algebra for the associated graded ring; these are the so-called gauge algebras obtaining their name from special examples appearing in E. Witten's gauge theories. The paper surveys basic definitions and properties but concentrates...
A ring is called a right -ring if its socle, , is projective. Nicholson and Watters have shown that if is a right -ring, then so are the polynomial ring and power series ring . In this paper, it is proved that, under suitable conditions, if has a (flat) projective socle, then so does the skew inverse power series ring and the skew polynomial ring , where is an associative ring equipped with an automorphism and an -derivation . Our results extend and unify many existing results....