It has been several attempts to generalize the ordinary commutative algebraic geometry to the noncom
It has been several attempts to generalize the ordinary commutative algebraic geometry to the noncommutative situation. The main problem in the direct generalization, is the lack of localization of noncommutative $k$-algebras, $k$ algebraically closed. This can only be done for Ore sets, and does not give a satisfactory solution to the problem.
In the study of flat deformations of $A$-modules when $A$ is a commutative, finitely generated $k$-algebra, one realizes that for each maximal ideal $\frak m$, putting $V=A/\frak m$, the deformation functor $\operatorname{Def}_V$ has a (unique up to nonunique isomorphism) prorepresenting hull (local formal moduli) $\hat{H}(V)$ isomorphic to the completed local ring, that is $\hat{H}(V)\cong\hat{A}_{\frak m}.$
In the general situation with $A$ not necessarily commutative, the deformation theory can be directly generalized to right (or left) $A$-modules, and we can replace the local complete rings with the hulls of the simple modules. In fact, for a finite dimensional $k$-algebra with family of simple right modules $V=\{V_i\}_{i=1}^n,$ we have the generalized Burnside theorem: $$A\cong(\hat{H}(V_i,V_j)\otimes\operatorname{Hom}_k(V_i,V_j))$$ the right hand side considered as a matrix algebra.
I will start by giving a short introduction to the deformation theory, and give an indication on how to compute the formal local moduli. Then I will clarify the abstract above. If there is any time left, an easy example will be given.
Date and Venue
Start Date
Venue
sala 0.03
Speaker
Arvid Siqveland
(Buskerud University College)
(Buskerud University College)
Area
Geometry and Topology