Let M be a matroid on [n] and E be the graded algebra generated over a field k generated by the elements 1, e 1 , . . . , e n . Let (M) be the ideal of E generated by the squares e 2 1 , . . . , e 2 n , elements of the form e i e j + a i j e j e i and 'boundaries of circuits', i.e., elements of the
Orlik–Solomon Type Algebras
✍ Scribed by David Forge; Michel Las Vergnas
- Publisher
- Elsevier Science
- Year
- 2001
- Tongue
- English
- Weight
- 92 KB
- Volume
- 22
- Category
- Article
- ISSN
- 0195-6698
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✦ Synopsis
We introduce χ-algebras, and show that a χ-algebra has the NBC basis property. We also show that a certain ideal used in the construction has the so-called BC basis property. The Orlik-Solomon algebra of a matroid, the Orlik-Terao algebra of a set of vectors, and the Cordovil algebra of an oriented matroid are χ-algebras. We define a new χ -algebra from a set of vectors, close to the Orlik-Terao, Orlik-Terao, and Cordovil algebras, but nevertheless different. Our proof provides a unified short and elementary proof of the NBC basis property for these algebras.
📜 SIMILAR VOLUMES
The Orlik-Solomon algebra A(G) of a matroid G is the free exterior algebra on the points, modulo the ideal generated by the circuit boundaries. On one hand, this algebra is a homotopy invariant of the complement of any complex hyperplane arrangement realizing G. On the other hand, some features of t
Let M = M(E) be a matroid on a linear ordered set E. The Orlik-Solomon Z-algebra OS(M) of M is the free exterior Z-algebra on E, modulo the ideal generated by the circuit boundaries. The Z-module OS(M) has a canonical basis called 'no broken circuit basis' and denoted nbc. Let e X = e i , e i ∈ X ⊂
The Orlik-Solomon algebra A of a matroid is isomorphic to the quotient of an exterior algebra E by a defining ideal I. We find an explicit presentation of the annihilator ideal of I or, equivalently, the E-module dual to A. As an application of that we provide a necessary, combinatorial condition fo
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