Auslander-Yoneda algebras and derived equivalences. Changchang Xi ( ~) ccxi/
|
|
- Cora Flynn
- 6 years ago
- Views:
Transcription
1 International Conference on Operads and Universal Algebra, Tianjin, China, July 5-9, Auslander- and derived Changchang Xi ( ~) xicc@bnu.edu.cn ccxi/
2 Abstract In this talk, we shall present a method of constructing derived between. In particular, we show that, for a self-injective algebra A and an A-module X, there is a derived equivalence between the of A X and A Ω(X) for any admissible subset Φ of N 0, where Ω is the Heller loop operator of A. This is a joint with Hu and Koenig.
3 Schedule of the talk Auslander- and corollaries
4 Definition of admissible sets N Φ = {0,1,2,3, }, the set of all natural numbers. N Definition Φ is called admissible if (1) 0 Φ and (2) for p,q,r Φ with p + q + r Φ, we have p + q Φ q + r Φ. Remark. Definition can be done for monoids.
5 Examples of admissible sets Examples: {0,i,j}, {0,1,3,6,9}, {0,1,3,5,7,,2n + 1}, Φ subset contains 0, = Φ m := {x m x Φ} adm. for m 3, {0,1,2,4} is NOT admissible.
6 Notations and definitions A: f. dim. algebra over a field k, A-mod: category of all f.g. left A-modules, X,Y A-mod Ext i A (X,Y): the i-th cohomology of X and Y. Definition algebra of a module X: M Ext A(X) := ExtA(X,X), i i=0 Multiplication: Concatenation of long exact sequences. This is an N-graded algebra.
7 Definition of Φ-AY Φ N, define E Φ A L (X) := ExtA i (X,X), i Φ Multiplication: x ExtA i (X,X), y Extj A (X,X), { xy if i + j Φ x y = 0 otherwise.
8 General model: Φ: subset of a monoid G, A = L A i : G-graded k-algebra, that is, i G A(Φ):= L A g, g Φ A i : k-space, A g A h A gh,g,h G, Multipl.: a g A g, a h A h, { a g a h if gh Φ, a g a h = 0 otherwise.
9 Definition of Φ-AY- Question: Is EA Φ (X) associative with 1? No, for arbitrary Φ. Yes, if Φ is admissible.
10 Definition of Φ-AY- Definition X A-mod, Φ: adm. subset of N, EA Φ (X) defined above is called Φ-AY-algebra of X. Examples: Φ = {0}, Endomorphism. Φ = N, ; Hochschild cohomology. Φ = 2N, Even. Φ = {0,i}, Trivial extension of End(X) by Ext i A (X,X).
11 Remark Warning: In general, EA Φ (X) is neither subalgebra nor quotient algebra of the algebra ExtA (X)! Φ = {0,1,3,9}, A = k[x]/(x 2 ), X = k
12 Category of complexes of A-modules A: f. dim. algebra. Complex X = (X i,d i ) i Z : a sequence in A-mod X 1 d 1 X 0 d 0 X 1 d 1 d i d i+1 = 0 for all i. Morphism f = (f i ) i Z : X Y : X 1 dx 1 X 0 d 0 X 1 f 1 f 0 f 1 Y 1 dy 1 Y 0 Each square commutes. d 0 Y Y 1
13 C(A): category of complexes with morphisms of complexes. f : X Y is quasi-iso. if f i induces isomorphism: H i (X ) H i (Y ) for all i, where H i (X ) := Ker(d i )/Im(d i 1 ), the i-th cohomology of X, f is null-homotopic if s i : X i Y i 1 such that, for all i, f i = d i Xs i+1 + s i d i 1.
14 Homotopy category Homotopy category K (A): Objects = objects of C(A), Morphism set: Hom K (A) (X,Y ) := Hom C(A)(X,Y ) {f g, } where, for f,g : X Y, we write f g if f g is null-homotopic.
15 category category D(A) of A: Localization of K (A) at all quasi-isomorphisms. That is, Objects of D(A) = Objects of K (A), but adding additional morphisms such that every quasi-iso. is invertible. D(A) is triangulated category.
16 X is bounded: almost all X i = 0. C b (A): category of bounded cpxs, K b (A): homotopy category of bounded cpxs, D b (A): derived category of bounded cpxs.
17 Definition A, B: f. dim. A and B is called derived equivalent if D b (A) and D b (B) are equivalent as triangulated categories. We write: A der B
18 1960 : Verdier + Grothendieck. After: Heller, Happel, Rickard, Keller,, Many branches: Algebraic geometry, representation theory, mathematical physics, Invariants: number of simple modules, Hochschild co- and homology, cyclic Hochshild co- and homology, finiteness of global dimension,
19 X,Y A-mod, Ext i A (X,Y) Hom D b (A)(X,Y[i]) Hom D b (A)(X[ i],y) where [1] is the shift functor of complexes. A-mod is embedded in D b (A) fully and faithfully.
20 The notion of almost (D, Φ)-split sequences. Φ: subset of N D: additive full subcat. of A-mod M: A-module add(m): additive subcat. gen. by M in A-mod
21 Almost (D, Φ)-split sequences Definition An exact sequence 0 X f M g Y 0 in A-mod is called almost (D, Φ)-split if (1) M D, (2) for any object D in D and i Φ, the induced maps Hom D b (A)(f,D [i]) and Hom D b (A)(D [ i],g) are surjective.
22 Almost (D, Φ)-split sequences M,D D, i Φ D [ i] g f 0 g X M Y 0 f D [i]
23 Example: P: projective-injective A-module, = any exact sequence 0 X P Y 0 is almost (add(p), Φ)-split sequence.
24 Theorem Φ: adm. set, M: A-module, 0 X M 1 Y 0: alm. (add(m),φ)-split seq. s.t. Ext i A (M,X) = 0 = Exti A (Y,M) for 0 i Φ = E Φ A der (X M) E Φ A (M Y).
25 Idea of the proof: Λ := E Φ A (X M), Γ := EΦ A (M Y) Construct a tilting complex over Λ, Prove the endomorphism algebra of the tilting complex is iso. to Γ.
26 Corollary. Φ: arbitrary adm. subset of N, A: Quasi-Frobenius algebra, X: A-module, = E Φ A (A X) der E Φ A (A Ωi A (X)).
27 Further comments The main result can be formulated for a triangulated category. In this case, Φ can be taken as an adm. subset of Z, The shift functor is replaced by an auto-equivalence functor, Exact sequence is generalized to triangle, Φ-AY algebra E Φ (X) is replaced by its quotient algebra.
28 Thank you!
Changchang Xi ( ~)
Noncommutative Algebraic Geometry: Shanghai Workshop 2011, Shanghai, China, September 12-16, 2011 Happel s Theorem for Infinitely Generated Tilting Modules Changchang Xi ( ~) Beijing, China Email: xicc@bnu.edu.cn
More informationStable equivalence functors and syzygy functors
Stable equivalence functors and syzygy functors Yosuke OHNUKI 29 November, 2002 Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588, Japan E-mail: ohnuki@cc.tuat.ac.jp
More informationOn root categories of finite-dimensional algebras
On root categories of finite-dimensional algebras Changjian Department of Mathematics, Sichuan University Chengdu August 2012, Bielefeld Ringel-Hall algebra for finitary abelian catgories Ringel-Hall Lie
More informationInfinite dimensional tilting modules, homological subcategories and recollements. Changchang Xi ( ~) Capital Normal University Beijing, China
The 15. International Conference on Representations of Algebras, Bielefeld, August 13-17, 2012 Infinite dimensional tilting, homological and recollements Changchang Xi ( ~) Capital Normal University Beijing,
More informationLie Algebra Cohomology
Lie Algebra Cohomology Carsten Liese 1 Chain Complexes Definition 1.1. A chain complex (C, d) of R-modules is a family {C n } n Z of R-modules, together with R-modul maps d n : C n C n 1 such that d d
More informationAlgebraic Geometry Spring 2009
MIT OpenCourseWare http://ocw.mit.edu 18.726 Algebraic Geometry Spring 2009 For information about citing these materials or our Terms of Use, visit: http://ocw.mit.edu/terms. 18.726: Algebraic Geometry
More informationMatrix factorisations
28.08.2013 Outline Main Theorem (Eisenbud) Let R = S/(f ) be a hypersurface. Then MCM(R) MF S (f ) Survey of the talk: 1 Define hypersurfaces. Explain, why they fit in our setting. 2 Define. Prove, that
More informationMatilde Marcolli and Goncalo Tabuada. Noncommutative numerical motives and the Tannakian formalism
Noncommutative numerical motives and the Tannakian formalism 2011 Motives and Noncommutative motives Motives (pure): smooth projective algebraic varieties X cohomology theories H dr, H Betti, H etale,...
More informationUNIVERSAL DERIVED EQUIVALENCES OF POSETS
UNIVERSAL DERIVED EQUIVALENCES OF POSETS SEFI LADKANI Abstract. By using only combinatorial data on two posets X and Y, we construct a set of so-called formulas. A formula produces simultaneously, for
More informationDERIVED EQUIVALENCES AND GORENSTEIN PROJECTIVE DIMENSION
DERIVED EQUIVALENCES AND GORENSTEIN PROJECTIVE DIMENSION HIROTAKA KOGA Abstract. In this note, we introduce the notion of complexes of finite Gorenstein projective dimension and show that a derived equivalence
More informationALGEBRAIC STRATIFICATIONS OF DERIVED MODULE CATEGORIES AND DERIVED SIMPLE ALGEBRAS
ALGEBRAIC STRATIFICATIONS OF DERIVED MODULE CATEGORIES AND DERIVED SIMPLE ALGEBRAS DONG YANG Abstract. In this note I will survey on some recent progress in the study of recollements of derived module
More informationAn introduction to derived and triangulated categories. Jon Woolf
An introduction to derived and triangulated categories Jon Woolf PSSL, Glasgow, 6 7th May 2006 Abelian categories and complexes Derived categories and functors arise because 1. we want to work with complexes
More informationBernhard Keller. University Paris 7 and Jussieu Mathematics Institute. On differential graded categories. Bernhard Keller
graded graded University Paris 7 and Jussieu Mathematics Institute graded Philosophy graded Question: What is a non commutative (=NC) scheme? Grothendieck, Manin,... : NC scheme = abelian category classical
More informationRECOLLEMENTS GENERATED BY IDEMPOTENTS AND APPLICATION TO SINGULARITY CATEGORIES
RECOLLEMENTS GENERATED BY IDEMPOTENTS AND APPLICATION TO SINGULARITY CATEGORIES DONG YANG Abstract. In this note I report on an ongoing work joint with Martin Kalck, which generalises and improves a construction
More informationNoncommutative invariant theory and Auslander s Theorem
Noncommutative invariant theory and Auslander s Theorem Miami University Algebra Seminar Robert Won Wake Forest University Joint with Jason Gaddis, Ellen Kirkman, and Frank Moore arxiv:1707.02822 November
More informationSTABLE MODULE THEORY WITH KERNELS
Math. J. Okayama Univ. 43(21), 31 41 STABLE MODULE THEORY WITH KERNELS Kiriko KATO 1. Introduction Auslander and Bridger introduced the notion of projective stabilization mod R of a category of finite
More informationDerived categories, perverse sheaves and intermediate extension functor
Derived categories, perverse sheaves and intermediate extension functor Riccardo Grandi July 26, 2013 Contents 1 Derived categories 1 2 The category of sheaves 5 3 t-structures 7 4 Perverse sheaves 8 1
More informationCATEGORY THEORY. Cats have been around for 70 years. Eilenberg + Mac Lane =. Cats are about building bridges between different parts of maths.
CATEGORY THEORY PROFESSOR PETER JOHNSTONE Cats have been around for 70 years. Eilenberg + Mac Lane =. Cats are about building bridges between different parts of maths. Definition 1.1. A category C consists
More informationGood tilting modules and recollements of derived module categories, II.
Good tilting modules and recollements of derived module categories, II. Hongxing Chen and Changchang Xi Abstract Homological tilting modules of finite projective dimension are investigated. They generalize
More informationSTABILITY OF FROBENIUS ALGEBRAS WITH POSITIVE GALOIS COVERINGS 1. Kunio Yamagata 2
STABILITY OF FROBENIUS ALGEBRAS WITH POSITIVE GALOIS COVERINGS 1 Kunio Yamagata 2 Abstract. A finite dimensional self-injective algebra will be determined when it is stably equivalent to a positive self-injective
More informationA TALE OF TWO FUNCTORS. Marc Culler. 1. Hom and Tensor
A TALE OF TWO FUNCTORS Marc Culler 1. Hom and Tensor It was the best of times, it was the worst of times, it was the age of covariance, it was the age of contravariance, it was the epoch of homology, it
More informationProperties of Triangular Matrix and Gorenstein Differential Graded Algebras
Properties of Triangular Matrix and Gorenstein Differential Graded Algebras Daniel Maycock Thesis submitted for the degree of Doctor of Philosophy chool of Mathematics & tatistics Newcastle University
More informationAFFINE PUSHFORWARD AND SMOOTH PULLBACK FOR PERVERSE SHEAVES
AFFINE PUSHFORWARD AND SMOOTH PULLBACK FOR PERVERSE SHEAVES YEHAO ZHOU Conventions In this lecture note, a variety means a separated algebraic variety over complex numbers, and sheaves are C-linear. 1.
More informationNoncommutative motives and their applications
MSRI 2013 The classical theory of pure motives (Grothendieck) V k category of smooth projective varieties over a field k; morphisms of varieties (Pure) Motives over k: linearization and idempotent completion
More informationHomological Methods in Commutative Algebra
Homological Methods in Commutative Algebra Olivier Haution Ludwig-Maximilians-Universität München Sommersemester 2017 1 Contents Chapter 1. Associated primes 3 1. Support of a module 3 2. Associated primes
More informationarxiv: v1 [math.kt] 27 Jan 2015
INTRODUCTION TO DERIVED CATEGORIES AMNON YEKUTIELI arxiv:1501.06731v1 [math.kt] 27 Jan 2015 Abstract. Derived categories were invented by Grothendieck and Verdier around 1960, not very long after the old
More informationA note on standard equivalences
Bull. London Math. Soc. 48 (2016) 797 801 C 2016 London Mathematical Society doi:10.1112/blms/bdw038 A note on standard equivalences Xiao-Wu Chen Abstract We prove that any derived equivalence between
More informationRepresentations of quivers
Representations of quivers Gwyn Bellamy October 13, 215 1 Quivers Let k be a field. Recall that a k-algebra is a k-vector space A with a bilinear map A A A making A into a unital, associative ring. Notice
More informationCombinatorial aspects of derived equivalence
Combinatorial aspects of derived equivalence Sefi Ladkani University of Bonn http://guests.mpim-bonn.mpg.de/sefil/ 1 What is the connection between... 2 The finite dimensional algebras arising from these
More information1. Algebraic vector bundles. Affine Varieties
0. Brief overview Cycles and bundles are intrinsic invariants of algebraic varieties Close connections going back to Grothendieck Work with quasi-projective varieties over a field k Affine Varieties 1.
More informationMATH 101B: ALGEBRA II PART A: HOMOLOGICAL ALGEBRA
MATH 101B: ALGEBRA II PART A: HOMOLOGICAL ALGEBRA These are notes for our first unit on the algebraic side of homological algebra. While this is the last topic (Chap XX) in the book, it makes sense to
More informationEtale cohomology of fields by Johan M. Commelin, December 5, 2013
Etale cohomology of fields by Johan M. Commelin, December 5, 2013 Etale cohomology The canonical topology on a Grothendieck topos Let E be a Grothendieck topos. The canonical topology T on E is given in
More informationarxiv: v1 [math.kt] 18 Dec 2009
EXCISION IN HOCHSCHILD AND CYCLIC HOMOLOGY WITHOUT CONTINUOUS LINEAR SECTIONS arxiv:0912.3729v1 [math.kt] 18 Dec 2009 RALF MEYER Abstract. We prove that continuous Hochschild and cyclic homology satisfy
More informationREPRESENTATION THEORY WEEK 9
REPRESENTATION THEORY WEEK 9 1. Jordan-Hölder theorem and indecomposable modules Let M be a module satisfying ascending and descending chain conditions (ACC and DCC). In other words every increasing sequence
More informationMutation classes of quivers with constant number of arrows and derived equivalences
Mutation classes of quivers with constant number of arrows and derived equivalences Sefi Ladkani University of Bonn http://www.math.uni-bonn.de/people/sefil/ 1 Motivation The BGP reflection is an operation
More informationDerivations and differentials
Derivations and differentials Johan Commelin April 24, 2012 In the following text all rings are commutative with 1, unless otherwise specified. 1 Modules of derivations Let A be a ring, α : A B an A algebra,
More informationSTEENROD OPERATIONS IN ALGEBRAIC GEOMETRY
STEENROD OPERATIONS IN ALGEBRAIC GEOMETRY ALEXANDER MERKURJEV 1. Introduction Let p be a prime integer. For a pair of topological spaces A X we write H i (X, A; Z/pZ) for the i-th singular cohomology group
More informationOn the Hochschild Cohomology and Homology of Endomorphism Algebras of Exceptional Sequences over Hereditary Algebras
Journal of Mathematical Research & Exposition Feb., 2008, Vol. 28, No. 1, pp. 49 56 DOI:10.3770/j.issn:1000-341X.2008.01.008 Http://jmre.dlut.edu.cn On the Hochschild Cohomology and Homology of Endomorphism
More informationWIDE SUBCATEGORIES OF d-cluster TILTING SUBCATEGORIES
WIDE SUBCATEGORIES OF d-cluster TILTING SUBCATEGORIES MARTIN HERSCHEND, PETER JØRGENSEN, AND LAERTIS VASO Abstract. A subcategory of an abelian category is wide if it is closed under sums, summands, kernels,
More informationCategories and functors
Lecture 1 Categories and functors Definition 1.1 A category A consists of a collection ob(a) (whose elements are called the objects of A) for each A, B ob(a), a collection A(A, B) (whose elements are called
More informationExtensions of covariantly finite subcategories
Arch. Math. 93 (2009), 29 35 c 2009 Birkhäuser Verlag Basel/Switzerland 0003-889X/09/010029-7 published online June 26, 2009 DOI 10.1007/s00013-009-0013-8 Archiv der Mathematik Extensions of covariantly
More informationMATH 233B, FLATNESS AND SMOOTHNESS.
MATH 233B, FLATNESS AND SMOOTHNESS. The discussion of smooth morphisms is one place were Hartshorne doesn t do a very good job. Here s a summary of this week s material. I ll also insert some (optional)
More informationHochschild and cyclic homology of a family of Auslander algebras
Hochschild and cyclic homology of a family of Auslander algebras Rachel Taillefer Abstract In this paper, we compute the Hochschild and cyclic homologies of the Auslander algebras of the Taft algebras
More informationAlgebraic Models for Homotopy Types III Algebraic Models in p-adic Homotopy Theory
Algebraic Models for Homotopy Types III Algebraic Models in p-adic Homotopy Theory Michael A. Mandell Indiana University Young Topologists Meeting 2013 July 11, 2013 M.A.Mandell (IU) Models in p-adic Homotopy
More informationMatrix factorizations over projective schemes
Jesse Burke (joint with Mark E. Walker) Department of Mathematics University of California, Los Angeles January 11, 2013 Matrix factorizations Let Q be a commutative ring and f an element of Q. Matrix
More informationHochschild Cohomology and Representation-finite Algebras. Ragnar-Olaf Buchweitz and Shiping Liu. Introduction
Hochschild Cohomology and Representation-finite Algebras Ragnar-Olaf Buchweitz and Shiping Liu Dedicated to Idun Reiten to mark her sixtieth birthday Introduction Hochschild cohomology is a subtle invariant
More informationOVERVIEW OF SPECTRA. Contents
OVERVIEW OF SPECTRA Contents 1. Motivation 1 2. Some recollections about Top 3 3. Spanier Whitehead category 4 4. Properties of the Stable Homotopy Category HoSpectra 5 5. Topics 7 1. Motivation There
More informationTilting categories with applications to stratifying systems
Journal of Algebra 302 (2006) 419 449 www.elsevier.com/locate/jalgebra Tilting categories with applications to stratifying systems Octavio Mendoza a,, Corina Sáenz b a Instituto de Matemáticas, UNAM, Circuito
More informationStasheffs A -algebras and Homotopy Gerstenhaber Algebras. Tornike Kadeishvili A. Razmadze Mathematical Institute of Tbilisi State University
1 Stasheffs A -algebras and Homotopy Gerstenhaber Algebras Tornike Kadeishvili A. Razmadze Mathematical Institute of Tbilisi State University 1 Twisting Elements 2 A dg algebra (A, d : A A +1, : A A A
More informationNotes on p-divisible Groups
Notes on p-divisible Groups March 24, 2006 This is a note for the talk in STAGE in MIT. The content is basically following the paper [T]. 1 Preliminaries and Notations Notation 1.1. Let R be a complete
More informationThus we get. ρj. Nρj i = δ D(i),j.
1.51. The distinguished invertible object. Let C be a finite tensor category with classes of simple objects labeled by a set I. Since duals to projective objects are projective, we can define a map D :
More informationGraded Calabi-Yau Algebras actions and PBW deformations
Actions on Graded Calabi-Yau Algebras actions and PBW deformations Q. -S. Wu Joint with L. -Y. Liu and C. Zhu School of Mathematical Sciences, Fudan University International Conference at SJTU, Shanghai
More informationNOTES ON BASIC HOMOLOGICAL ALGEBRA 0 L M N 0
NOTES ON BASIC HOMOLOGICAL ALGEBRA ANDREW BAKER 1. Chain complexes and their homology Let R be a ring and Mod R the category of right R-modules; a very similar discussion can be had for the category of
More informationAn overview of D-modules: holonomic D-modules, b-functions, and V -filtrations
An overview of D-modules: holonomic D-modules, b-functions, and V -filtrations Mircea Mustaţă University of Michigan Mainz July 9, 2018 Mircea Mustaţă () An overview of D-modules Mainz July 9, 2018 1 The
More informationOperads. Spencer Liang. March 10, 2015
Operads Spencer Liang March 10, 2015 1 Introduction The notion of an operad was created in order to have a well-defined mathematical object which encodes the idea of an abstract family of composable n-ary
More informationIwasawa algebras and duality
Iwasawa algebras and duality Romyar Sharifi University of Arizona March 6, 2013 Idea of the main result Goal of Talk (joint with Meng Fai Lim) Provide an analogue of Poitou-Tate duality which 1 takes place
More informationA course on cluster tilted algebras
Ibrahim Assem Département de mathématiques Université de Sherbrooke Sherbrooke, Québec Canada JK R A course on cluster tilted algebras march 06, mar del plata Contents Introduction 5 Tilting in the cluster
More informationQUILLEN MODEL STRUCTURES FOR RELATIVE HOMOLOGICAL ALGEBRA
QUILLEN MODEL STRUCTURES FOR RELATIVE HOMOLOGICAL ALGEBRA J. DANIEL CHRISTENSEN AND MARK HOVEY Abstract. An important example of a model category is the category of unbounded chain complexes of R-modules,
More informationHopfological algebra and categorification at a root of unity: the first steps
arxiv:math/0509083v2 [math.qa] 25 Mar 2006 Hopfological algebra and categorification at a root of unity: the first steps Contents Mikhail Khovanov September 6, 2005 1 Hopfological algebra 1 2 Examples
More informationOne-point extensions and derived equivalence
Journal of Algebra 264 (2003) 1 5 www.elsevier.com/locate/jalgebra One-point extensions and derived equivalence Michael Barot a, and Helmut Lenzing b a Instituto de Matemáticas, UNAM, Mexico 04510 D.F.,
More informationALGEBRAS OF DERIVED DIMENSION ZERO
Communications in Algebra, 36: 1 10, 2008 Copyright Taylor & Francis Group, LLC ISSN: 0092-7872 print/1532-4125 online DOI: 10.1080/00927870701649184 Key Words: algebra. ALGEBRAS OF DERIVED DIMENSION ZERO
More informationOn differential graded categories
On differential graded categories Bernhard Keller Abstract. Differential graded categories enhance our understanding of triangulated categories appearing in algebra and geometry. In this survey, we review
More informationDifferential Graded Algebras and Applications
Differential Graded Algebras and Applications Jenny August, Matt Booth, Juliet Cooke, Tim Weelinck December 2015 Contents 1 Introduction 2 1.1 Differential Graded Objects....................................
More informationTRIANGULATED CATEGORIES, SUMMER SEMESTER 2012
TRIANGULATED CATEGORIES, SUMMER SEMESTER 2012 P. SOSNA Contents 1. Triangulated categories and functors 2 2. A first example: The homotopy category 8 3. Localization and the derived category 12 4. Derived
More informationHungry, Hungry Homology
September 27, 2017 Motiving Problem: Algebra Problem (Preliminary Version) Given two groups A, C, does there exist a group E so that A E and E /A = C? If such an group exists, we call E an extension of
More informationRelative singularity categories and Gorenstein-projective modules
Math. Nachr. 284, No. 2 3, 199 212 (2011) / DOI 10.1002/mana.200810017 Relative singularity categories and Gorenstein-projective modules Xiao-Wu Chen Department of Mathematics, University of Science and
More informationTCC Homological Algebra: Assignment #3 (Solutions)
TCC Homological Algebra: Assignment #3 (Solutions) David Loeffler, d.a.loeffler@warwick.ac.uk 30th November 2016 This is the third of 4 problem sheets. Solutions should be submitted to me (via any appropriate
More informationNONCOMMUTATIVE GRADED GORENSTEIN ISOLATED SINGULARITIES
NONCOMMUTATIVE GRADED GORENSTEIN ISOLATED SINGULARITIES KENTA UEYAMA Abstract. Gorenstein isolated singularities play an essential role in representation theory of Cohen-Macaulay modules. In this article,
More informationMath 210B. The bar resolution
Math 210B. The bar resolution 1. Motivation Let G be a group. In class we saw that the functorial identification of M G with Hom Z[G] (Z, M) for G-modules M (where Z is viewed as a G-module with trivial
More informationA pairing in homology and the category of linear complexes of tilting modules for a quasi-hereditary algebra
A pairing in homology and the category of linear complexes of tilting modules for a quasi-hereditary algebra Volodymyr Mazorchuk and Serge Ovsienko Abstract We show that there exists a natural non-degenerate
More informationA GLIMPSE OF ALGEBRAIC K-THEORY: Eric M. Friedlander
A GLIMPSE OF ALGEBRAIC K-THEORY: Eric M. Friedlander During the first three days of September, 1997, I had the privilege of giving a series of five lectures at the beginning of the School on Algebraic
More informationStable Homotopy Theory A gateway to modern mathematics.
Stable Homotopy Theory A gateway to modern mathematics. Sunil Chebolu Department of Mathematics University of Western Ontario http://www.math.uwo.ca/ schebolu 1 Plan of the talk 1. Introduction to stable
More informationFundamental group. Chapter The loop space Ω(X, x 0 ) and the fundamental group
Chapter 6 Fundamental group 6. The loop space Ω(X, x 0 ) and the fundamental group π (X, x 0 ) Let X be a topological space with a basepoint x 0 X. The space of paths in X emanating from x 0 is the space
More informationDerived Equivalences of Triangular Matrix Rings Arising from Extensions of Tilting Modules
Algebr Represent Theor (2011) 14:57 74 DOI 10.1007/s10468-009-9175-0 Derived Equivalences of Triangular Matrix Rings Arising from Extensions of Tilting Modules Sefi Ladkani Received: 1 September 2008 /
More informationHochschild homology and Grothendieck Duality
Hochschild homology and Grothendieck Duality Leovigildo Alonso Tarrío Universidade de Santiago de Compostela Purdue University July, 1, 2009 Leo Alonso (USC.es) Hochschild theory and Grothendieck Duality
More informationRealizing Families of Landweber Exact Theories
Realizing Families of Landweber Exact Theories Paul Goerss Department of Mathematics Northwestern University Summary The purpose of this talk is to give a precise statement of 1 The Hopkins-Miller Theorem
More informationPeriodicity of selfinjective algebras of polynomial growth
Periodicity of selfinjective algebras of polynomial growth 0 Periodicity of selfinjective algebras of polynomial growth Jerzy Białkowski (Nagoya, November 2013) joint work with Karin Erdmann and Andrzej
More informationHOMEWORK SET 3. Local Class Field Theory - Fall For questions, remarks or mistakes write me at
HOMEWORK SET 3 Local Class Field Theory - Fall 2011 For questions, remarks or mistakes write me at sivieroa@math.leidneuniv.nl. Exercise 3.1. Suppose A is an abelian group which is torsion (every element
More informationA visual introduction to Tilting
A visual introduction to Tilting Jorge Vitória University of Verona http://profs.sci.univr.it/ jvitoria/ Padova, May 21, 2014 Jorge Vitória (University of Verona) A visual introduction to Tilting Padova,
More informationThe Depth Formula for Modules with Reducible Complexity
The Depth Formula for Modules with Reducible Complexity Petter Andreas Bergh David A Jorgensen Technical Report 2010-10 http://wwwutaedu/math/preprint/ THE DEPTH FORMULA FOR MODULES WITH REDUCIBLE COMPLEXITY
More informationAuslander-Reiten theory for simply connected differential graded algebras
Auslander-Reiten theory for simply connected differential graded algebras Dissertation vorgelegt von Karsten Schmidt an der Fakultät für Elektrotechnik, Informatik und Mathematik der Universität Paderborn
More informationPROBLEMS, MATH 214A. Affine and quasi-affine varieties
PROBLEMS, MATH 214A k is an algebraically closed field Basic notions Affine and quasi-affine varieties 1. Let X A 2 be defined by x 2 + y 2 = 1 and x = 1. Find the ideal I(X). 2. Prove that the subset
More informationDedicated to Helmut Lenzing for his 60th birthday
C O L L O Q U I U M M A T H E M A T I C U M VOL. 8 999 NO. FULL EMBEDDINGS OF ALMOST SPLIT SEQUENCES OVER SPLIT-BY-NILPOTENT EXTENSIONS BY IBRAHIM A S S E M (SHERBROOKE, QUE.) AND DAN Z A C H A R I A (SYRACUSE,
More informationDescent on the étale site Wouter Zomervrucht, October 14, 2014
Descent on the étale site Wouter Zomervrucht, October 14, 2014 We treat two eatures o the étale site: descent o morphisms and descent o quasi-coherent sheaves. All will also be true on the larger pp and
More informationRepresentation type, boxes, and Schur algebras
10.03.2015 Notation k algebraically closed field char k = p 0 A finite dimensional k-algebra mod A category of finite dimensional (left) A-modules M mod A [M], the isomorphism class of M ind A = {[M] M
More informationSingularity Categories, Schur Functors and Triangular Matrix Rings
Algebr Represent Theor (29 12:181 191 DOI 1.17/s1468-9-9149-2 Singularity Categories, Schur Functors and Triangular Matrix Rings Xiao-Wu Chen Received: 14 June 27 / Accepted: 12 April 28 / Published online:
More informationKOSZUL DUALITY FOR STRATIFIED ALGEBRAS I. QUASI-HEREDITARY ALGEBRAS
KOSZUL DUALITY FOR STRATIFIED ALGEBRAS I. QUASI-HEREDITARY ALGEBRAS VOLODYMYR MAZORCHUK Abstract. We give a complete picture of the interaction between Koszul and Ringel dualities for quasi-hereditary
More informationBERTRAND GUILLOU. s G q+r
STABLE A 1 -HOMOTOPY THEORY BERTRAND GUILLOU 1. Introduction Recall from the previous talk that we have our category pointed A 1 -homotopy category Ho A 1, (k) over a field k. We will often refer to an
More informationRingel modules and homological subcategories
Ringel modules and homological subcategories Hongxing Chen and Changchang Xi Abstract Given a good n-tilting module T over a ring A, let B be the endomorphism ring of T, it is an open question whether
More informationare additive in each variable. Explicitly, the condition on composition means that given a diagram
1. Abelian categories Most of homological algebra can be carried out in the setting of abelian categories, a class of categories which includes on the one hand all categories of modules and on the other
More informationCATEGORICAL ASPECTS OF ALGEBRAIC GEOMETRY IN MIRROR SYMMETRY ABSTRACTS
CATEGORICAL ASPECTS OF ALGEBRAIC GEOMETRY IN MIRROR SYMMETRY Alexei Bondal (Steklov/RIMS) Derived categories of complex-analytic manifolds Alexender Kuznetsov (Steklov) Categorical resolutions of singularities
More informationGraded modules over generalized Weyl algebras
Graded modules over generalized Weyl algebras Advancement to Candidacy Robert Won Advised by: Dan Rogalski December 4, 2014 1 / 41 Overview 1 Preliminaries Graded rings and modules Noncommutative things
More informationINFINITE DIMENSIONAL MODULES FOR FROBENIUS KERNELS
INFINITE DIMENSIONAL MODULES FOR FROBENIUS KERNELS JULIA PEVTSOVA Abstract. We prove that the projectivity of an arbitrary (possibly infinite dimensional) module for a Frobenius kernel can be detected
More informationStable model categories are categories of modules
Topology 42 (2003) 103 153 www.elsevier.com/locate/top Stable model categories are categories of modules Stefan Schwede a; ;1, Brooke Shipley b;2 a SFB 478, Geometrische Strukturen in der Mathematik, Westfalische
More informationEXT, TOR AND THE UCT
EXT, TOR AND THE UCT CHRIS KOTTKE Contents 1. Left/right exact functors 1 2. Projective resolutions 2 3. Two useful lemmas 3 4. Ext 6 5. Ext as a covariant derived functor 8 6. Universal Coefficient Theorem
More informationK-theory and derived equivalences (Joint work with D. Dugger) Neeman proved the above result for regular rings.
K-theory and derived equivalences (Joint work with D. Dugger) Main Theorem: If R and S are two derived equivalent rings, then K (R) = K (S). Neeman proved the above result for regular rings. Main Example
More informationHOMOLOGICAL DIMENSIONS AND REGULAR RINGS
HOMOLOGICAL DIMENSIONS AND REGULAR RINGS ALINA IACOB AND SRIKANTH B. IYENGAR Abstract. A question of Avramov and Foxby concerning injective dimension of complexes is settled in the affirmative for the
More informationDerived Canonical Algebras as One-Point Extensions
Contemporary Mathematics Derived Canonical Algebras as One-Point Extensions Michael Barot and Helmut Lenzing Abstract. Canonical algebras have been intensively studied, see for example [12], [3] and [11]
More informationAUSLANDER-REITEN THEORY FOR FINITE DIMENSIONAL ALGEBRAS. Piotr Malicki
AUSLANDER-REITEN THEORY FOR FINITE DIMENSIONAL ALGEBRAS Piotr Malicki CIMPA, Mar del Plata, March 2016 3. Irreducible morphisms and almost split sequences A algebra, L, M, N modules in mod A A homomorphism
More informationarxiv: v1 [math.rt] 12 Jan 2016
THE MCM-APPROXIMATION OF THE TRIVIAL MODULE OVER A CATEGORY ALGEBRA REN WANG arxiv:1601.02737v1 [math.rt] 12 Jan 2016 Abstract. For a finite free EI category, we construct an explicit module over its category
More information