We show that the quotients of the continuous cluster category Cπ and the rational subcategory X modulo the additive subcategory generated by any cluster are abelian categories and we show that they are isomorphic to categories of infinite and finite length modules, respectively, over the endomorphism ring of the cluster. These theorems extend the theorems of Caldero-ChapotonSchiffler and Buan-M...

The paper gives a new proof that the model categories of stable modules for the rings Z=p and Z=pŒ��=.�/ are not Quillen equivalent. The proof uses homotopy endomorphism ring spectra. Our considerations lead to an example of two differential graded algebras which are derived equivalent but whose associated model categories of modules are not Quillen equivalent. As a bonus, we also obtain derive...

K: a global function field of characteristicp # 0 E a fixed algebraic closure of K 00: a distinguished place of K A: the ring of functions in K regular away from cx> F,: a finite field which is an A-algebra VI the A-characteristic of F, (this means that the prime ideal pt, of v is the kernel of the structure morphism A + F4) 4 : a Drinfeld A-module over F, of rank d 7~: The Frobenius endomorphi...

We determine the isogeny classes of abelian surfaces over Fq whose group of Fq-rational points has order divisible by q . We also solve the same problem for Jacobians of genus-2 curves. In a recent paper [4], Ravnshøj proved: if C is a genus-2 curve over a prime field Fp, and if one assumes that the endomorphism ring of the Jacobian J of C is the ring of integers in a primitive quartic CM-field...

This survey article is based on a joint work with Ehud Hrushovski on some Bezout difference rings ([19]). We study in a model-theoretic point of view certain classes of difference rings, namely rings with a distinguished endomorphism and more particularly rings of sequences over a field with a shift. First we will recall some results on difference fields. A difference field is a difference ring...

In this paper, the endomorphisms, the half-strong endomorphisms, the locally strong endomorphisms, the quasi-strong endomorphisms, the strong endomorphisms and the automorphisms of a join of cycle n C and a vertex y are investigated. Some enumerative problems concerning these graphs are solved. In particular, the endomorphism spectrums and the endomorphism types of these graphs are given. It ha...

We determine the isogeny classes of abelian surfaces over Fq whose group of Fq-rational points has order divisible by q. We also solve the same problem for Jacobians of genus-2 curves. In a recent paper [1], Ravnshøj proved: if C is a genus-2 curve over a prime field Fp, and if one assumes that the endomorphism ring of the Jacobian J of C is the ring of integers in a primitive quartic CM-field,...

Let M be a right module over a ring R. In this manuscript, we shall study on a special case of F-inverse split modules where F is a fully invariant submodule of M introduced in [12]. We say M is Z 2(M)-inverse split provided f^(-1)(Z2(M)) is a direct summand of M for each endomorphism f of M. We prove that M is Z2(M)-inverse split if and only if M is a direct...

In an abelian category, a commutative quadrangle is called bicartesian if its diagonal sequence is short exact, i.e. if it is a pullback and a pushout. A commutative quadrangle is bicartesian if and only if we get induced isomophisms on the horizontal kernels and on the horizontal cokernels. In a triangulated category in the sense of Verdier [3, Def. 1-1], a commutative quadrangle is called hom...

Abstract We describe the universal target of annular Khovanov–Rozansky link homology functors as homotopy category a free symmetric monoidal linear generated by one object and endomorphism. This categorifies ring functions admits categorical analogues plethystic transformations, which we use to characterize invariants Coxeter braids. Further, prove existence group actions on cabled tangles intr...