English

Obstructing extensions of the functor Spec to noncommutative rings

Rings and Algebras 2013-03-14 v3 Algebraic Geometry Operator Algebras

Abstract

In this paper we study contravariant functors from the category of rings to the category of sets whose restriction to the full subcategory of commutative rings is isomorphic to the prime spectrum functor Spec. The main result reveals a common characteristic of these functors: every such functor assigns the empty set to M_n(C) for n >= 3. The proof relies, in part, on the Kochen-Specker Theorem of quantum mechanics. The analogous result for noncommutative extensions of the Gelfand spectrum functor for C*-algebras is also proved.

Keywords

Cite

@article{arxiv.1101.2239,
  title  = {Obstructing extensions of the functor Spec to noncommutative rings},
  author = {Manuel L. Reyes},
  journal= {arXiv preprint arXiv:1101.2239},
  year   = {2013}
}

Comments

23 pages. To appear in Israel J. Math. Title was changed; introduction was rewritten; old Section 2 was removed to streamline the exposition; final section was rewritten to omit an error in the earlier proof of Theorem 1.2

R2 v1 2026-06-21T17:10:42.330Z