Journal of Generalized Lie Theory and Applications

Geometry of Noncommutative k-Algebras

Arvid Siqveland

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Let X be a scheme over an algebraically closed field k, and let $x\in\operatorname{Spec} R\subseteq X$ be a closed point corresponding to the maximal ideal $\mathfrak{m}\subseteq R$. Then $\hat{\mathcal{O}}_{X,x}$ is isomorphic to the prorepresenting hull, or local formal moduli, of the deformation functor $\mathrm{Def}_{R/\mathfrak{m}}:\underline{\ell}\rightarrow\mathrm{Sets}$. This suffices to reconstruct $X$ up to etalé coverings. For a noncommutative $k$-algebra $A$ the simple modules are not necessarily of dimension one, and there is a geometry between them. We replace the points in the commutative situation with finite families of points in the noncommutative situation, and replace the geometry of points with the geometry of sets of points given by noncommutative deformation theory. We apply the theory to the noncommutative moduli of three-dimensional endomorphisms.

Article information

J. Gen. Lie Theory Appl., Volume 5 (2011), Article ID G110107, 12 pages.

First available in Project Euclid: 29 September 2011

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Primary: 14A22: Noncommutative algebraic geometry [See also 16S38] 14D22: Fine and coarse moduli spaces 14D23: Stacks and moduli problems 16L30: Noncommutative local and semilocal rings, perfect rings


Siqveland, Arvid. Geometry of Noncommutative k-Algebras. J. Gen. Lie Theory Appl. 5 (2011), Article ID G110107, 12 pages. doi:10.4303/jglta/G110107.

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