2 citations · 4 across the 25 of their papers we have counts for
26 papers
Skew fields not finitely generated as algebras
K. R. Goodearl, E. S. Letzter
An associative division algebra D is said to be _affine_ over a central subfield k if D is finitely generated as a k-algebra. In 1956 Amitsur famously proved that, when k is uncoun…
On free subsemigroups of associative algebras
Edward S. Letzter
In 1992, following earlier conjectures of Lichtman and Makar-Limanov, Klein conjectured that a noncommutative domain must contain a free, multiplicative, noncyclic subsemigroup. He…
On -commutative power and Laurent series rings at roots of unity
Edward S. Letzter, Linhong Wang, Xingting Wang
We continue the first and second authors' study of -commutative power series rings and Laurent series rings ,…
On graded characterizations of finite dimensionality for algebraic algebras
Edward S. Letzter
We observe that a finitely generated algebraic algebra R (over a field) is finite dimensional if and only if the associated graded ring grR is right noetherian, if and only if grR…
Continuity is an adjoint functor
Edward S. Letzter
For topological spaces and , a (not necessarily continuous) function naturally induces a functor from the category of closed subsets of (with morphis…
Goldie Ranks of Skew Power Series Rings of Automorphic Type
Edward S. Letzter, Linhong Wang
Let A be a semprime, right noetherian ring equipped with an automorphism alpha, and let B := A[[y; alpha]] denote the corresponding skew power series ring (which is also semiprime…