We introduce the notion of “local system of ZT -twisted vertex operators” on a Z2-graded vector space M , generalizing the notion of local system of vertex operators [Li]. First, we prove that any local system of ZT -twisted vertex operators on M has a vertex superalgebra structure with an automorphism σ of order T with M as a σ-twisted module. Then we prove that for a vertex (operator) superal...

Recently many researchers have worked on problems connected with various graded algebras associated to an ideal I in a local ring R. Two algebras in particular have received the most attention: the associated graded algebra of Z, gr,( R) = R/Z@ Z/Z’@ ... , and the Rees algebra of Z, defined to be R[Zt]. Brodmann [2] and Goto and Shimoda [9] have studied the local cohomology of R[Zr] for certain...

Graded-CTL is an extension of CTL with graded quantifiers which allow to reason about either at least or all but any number of possible futures. In this paper we show an extension of the NuSMV model-checker implementing symbolic algorithms for graded-CTL model checking. The implementation is based on the CUDD library, for BDDs and ADDs manipulation, and includes also an efficient algorithm for ...

BRST-resolution is studied for the principally graded Wakimoto module of ŝl2 recently found in [9]. The submodule structure is completely determined and irreducible representations can be obtained as the zero-th cohomology group. e-mail:[email protected]

A double-exponential upper bound is obtained for the degree and for the complexity of constructing a standard basis of a D-module. This generalizes a well-known bound for the complexity of a Gröbner basis of a module over the algebra of polynomials. It should be emphasized that the bound obtained cannot be deduced immediately from the commutative case. To get the bound in question, a new techni...

Let G be a simple algebraic group over C with the Weyl group W . For a unipotent element u ∈ G, let Bu be the variety of Borel subgroups of G containing u. Let L be a Levi subgroup of a parabolic subgroup of G with the Weyl subgroup WL of W . Assume that u ∈ L and let B L u be a similar variety as Bu for L. We describe, for a certain choice of u ∈ L and e ≥ 1, the W -module ⊕ n≡k mod e H2n(Bu) ...

Given a strong deformation retract M of an algebra A, there are several apparently distinct ways ([9],[19], [13], [24],[15], [18], [17]) of constructing a coderivation on the tensor coalgebra of M in such a way that the resulting complex is quasi isomorphic to the classical (differential tor) [7] bar construction of A. We show that these methods are equivalent and are determined combinatorially...

Let $G$ be an abelian group with identity $e$. $R$ a $G$-graded commutative ring and $M$ graded $R$-module. In this paper we will obtain some results concerning the generalized 2-absorbing submodules their homogeneous components. Special attention has been paid, when rings are gr-Noetherian, to find extra properties of these submodules.

We show that the category of projective modules over a graded commutative ring admits a triangulation with respect to module suspension if and only if the ring is a finite product of graded fields and exterior algebras on one generator over a graded field (with a unit in the appropriate degree). We also classify the ungraded commutative rings for which the category of projective modules admits ...

We classify localising subcategories of the stable module category of a finite group that are closed under tensor product with simple (or, equivalently all) modules. One application is a proof of the telescope conjecture in this context. Others include new proofs of the tensor product theorem and of the classification of thick subcategories of the finitely generated modules which avoid the use ...