We ask when a finite set of t-structures in a triangulated category can be ‘averaged’ into one t-structure or, equivalently, when the extension closure of a finite set of aisles is again an aisle. There is a straightforward, positive answer for a finite set of compactly generated t-structures in a big triangulated category. For piecewise tame hereditary categories, we give a criterion for when ...

Let V be a vertex operator algebra and g an automorphism of order T . We construct a sequence of associative algebras Ag,n(V ) with n ∈ 1 T Z nonnegative such that Ag,n(V ) is a quotient of Ag,n+1/T (V ) and a pair of functors between the category of Ag,n(V )-modules which are not Ag,n−1/T (V )-modules and the category of admissible V -modules. These functors exhibit a bijection between the sim...

in this work, we describe an adjunction between the comma category of set-based monads under the v -powerset monad and the category of associative lax extensions of set-based monads to the category of v -relations. in the process, we give a general construction of the kleisli extension of a monad to the category of v-relations.

It is shown that the derived dimension of any representation-finite Artin algebra is at most one. Mathematics Subject Classification 2000: 16G10, 18E30, 18E10. Let T be a triangulated category, and I and J two full subcategories of T . Denote by 〈I〉 the smallest full subcategory of T containing I and closed under shifts, finite direct sums and direct summands. Denote by I∗J the full subcategory...

eight accessions of thyme medicinal plant, belonging to iranian endemic thymus daënensis, t. eriocalyx, t. migricus and an unknown thymus spp species, were tested for karyotypic analysis, using squash technique and 2% (w/v) aceto-orcein staining method. chromosomal parameters examined were: short arm (s), long arm (l), total length of chromosome (tl), arm ratio (ar), r-value, total chromosome v...

In the work of Hoshino, Kato and Miyachi, [8], the authors look at t-structures induced by a compact object, C, of a triangulated category, T , which is rigid in the sense of Iyama and Yoshino, [9]. Hoshino, Kato and Miyachi show that such an object yields a non-degenerate t-structure on T whose heart is equivalent to Mod(End(C)). Rigid objects in a triangulated category can the thought of as b...