ALGEBRA AND GEOMETRY SEMINAR
Department of Mathematics, Uppsala University
Usually: Tuesday's 15.15-17.00 in 64119

2018

Coming seminars:


2018-12-18 Helena Jonsson (Uppsala)
2018-12-04 Rowena Paget (Kent)
2018-12-04 Rolf Farnsteiner (Kiel)
2018-12-04 Petter Andreas Bergh (Trondheim)

2018-11-27 Chrysostomos Psaroudakis (Thessaloniki)
2018-11-20 Lorenzo Guerrieri (Catania) Asymptotic invariants of ideals with Noetherian symbolic Rees algebra and applications to cover ideals

Let I be an ideal in a polynomial ring R. For m ≥ 1, let I^m denote its m-th ordinary power and I^(m)
denote its m-th symbolic power. A well studied problem, having application both in ring theory and in
algebraic geometry, is to determine whether these two powers coincide and to find elements in I^(m) but
not in I^m, when they exist. The m-th symbolic defect, sdefect(I,m), of I is defined to be the minimal
number of generators of the R-module I^(m)/ I^m.
In this work, assuming that the symbolic Rees algebra of I is Noetherian, we prove that sdefect(I,m) is
an asymptotically quasipolynomial function in m. Then, after giving a decomposition of the symbolic
powers of I in terms of smaller symbolic powers, we compute the Waldschimdt constant of I in the
monomial case, and we also compute explicit formulas for the symbolic defect of cover ideals of some
graphs.

joint work with B. Drabkin (U. Nebraska-Lincoln).


2018-11-06 Oleksandra Gasanova (Uppsala) On the Ratliff-Rush closure of monomial ideals


Let R be a commutative Noetherian ring and I a regular ideal in it. Then I^{k+1}:I^k, k>=0,
is a chain of ideals whose union is called the Ratliff-Rush closure of I, Rat(I). Rat(I) is the unique
largest ideal with the same high powers as I, and furthermore, if I is an m-primary ideal in a local
ring (R,m), then Rat(I) is the unique largest ideal that has the same Hilbert polynomial as I. Some
other nice properties of Rat(I) are known as well. One problem computing Rat(I) is the fact that one
does not know whether the chain has stabilized: one can have arbitrarily many equalities, followed by
further ascending. In my talk I will focus on a certain class of monomial ideals in polynomial rings
and will present an algorithm for computing Rat(I) for these ideals.


2018-10-23 Rafael Mrden (Zagreb) BGG complexes in singular infinitesimal character via Penrose Transform

Bernstein, Gelfand and Gelfand showed how to resolve a finite-dimensional module of a
semisimple Lie algebra, by direct sums of Verma modules (induced from the Borel subalgebra). This
construction was later generalized by Lepowsky to arbitrary parabolic subalgebras, and the result became
known as BGG resolution. Duals of these resolutions also appeared in the geometric form, in the work of
Čap, Slovak and Souček. In the talk I will describe a construction of analogues of BGG resolutions in
singular infinitesimal character, in the holomorphic geometric setting. Here the resolved modules are
infinite-dimensional. I will work over the Hermitian space in type C, and also give an example for a
non-Hermitian space. The main tool is the Penrose transform.










Previous seminars:


2018-10-16 Ruari Walker (Paris) Affine Hecke algebras and generalisations of quiver Hecke algebras for type B
2018-10-02 Walter Mazorchuk (Uppsala) Gelfand-Zeitlin modules and divided difference operators
2018-09-18 Julian Kuelshammer (Uppsala) Differential biquivers and the tame-wild dichotomy theorem
2018-09-04 Wushi Goldring (Stockholm) Propagating algebraicity of automorphic representations via Langlands functoriality
2018-06-12 Andrea Pasquali (Uppsala) Jacobian algebras and their skew group algebras
2018-06-05 Petter Restadh (Uppsala) The selfinjective Nakayama algebras and their complexity
2018-05-22 Daniel Ahlsen (Uppsala) Krull-Schmidt-Remak and Jordan-Hölder in abelian categories
2018-05-08 Jonathan Nilsson (Orebro) Representation theory for Lie algebras of vector fields
2018-04-17 Markus Thuresson (Uppsala) Drinfeld center
2018-03-27 Vanessa Miemietz (Norwich) Analogues of centralizer subalgebras for fiat 2-categories
2018-03-21 Michael Ehrig (Sydney) Lie superalgebras via Schur-Weyl duality and categorification
2018-03-21 Julian Kuelshammer (Stuttgart) Exceptional collections and ring extensions
2018-03-21 David Ploog (Berlin) Worm diagrams and full exceptional sequences of modules
2018-03-21 Elisa Postinghel (Loughborough) Newton-Okounkov bodies in algebraic geometry
2018-03-13 Marco D'Anna (Catania) Numerical duplication and its associated graded ring
2018-02-20 Michael Ehrig (Sydney) Relative cellular algebras
2018-02-13 Nancy Abdallah (Linkoeping) Combinatorial invariance of KLV polynomials for fixed point free involutions
2018-02-13 Steffen Oppermann (Trondheim) Change of rings and singularity categories
2018-01-30 Olof Bergvall (Uppsala) Moduli of genus three curves with symplectic level two structure


2017

2017-12-12 Melanija Mitrovic (Nis/Västerås) Constructive semigroups with apartness - a new approach to semigroup theory
2017-11-07 Emre Sertoz (Leipzig) Enumerative geometry of double spin curves
2017-10-24 Chih-Whi Chen (Uppsala) Affine periplectic Brauer algebras
2017-10-10 Xiaoting Zhang (Uppsala) Pyramids, strict monoidal actions and 2-representations
2017-09-26 Victoria Gould (York) Purity of S-acts and coherency for monoids
2017-09-26 Mark Lawson (Edinburgh) Basic Boolean inverse monoids
2017-09-26 Stuart Margolis (Bar Ilan) Boolean Representations of Simplicial Complexes and Lattice Representations: Beyond Matroids
2017-09-19 Yu Liu (Uppsala) n-cluster tilting subcategories and localizations on extriangulated categories
2017-09-05 Andrea Pasquali (Uppsala) Self-injective quivers with potential from Postnikov diagrams
2017-08-22 Kevin Coulembier (Sydney) Representation theory of periplectic Lie and Brauer algebra
2017-06-08 Seidon Alsaody (Lyon) Schemes, sheaves, torsors and octonions: an application of Grothendieck's philosophy
2017-05-30 Elin Persson Westin (Uppsala) Tilting modules over n-cluster tilting subcategories
2017-05-16 Helena Jonsson (Uppsala) Bimodules over dual numbers
2017-04-20 Peter Jorgensen (Newcastle) Thick subcategories of d-abelian categories
2017-04-04 Simone Giovannini (Padova/Uppsala) n-representation infinite algebras from McKay quivers of metacyclic groups
2017-03-21 Lisa Nicklasson (Stockholm) The Lefschetz properties of monomial algebras of positive characteristic
2017-03-07 Love Forsberg (Uppsala) Multisemigroup of ideals arising from a cyclic quiver
2017-02-21 Xiaoting Zhang (Uppsala) Characterisation of k-split bimodules and its applications
2017-01-31 Hiroyuki Nakaoka (Kagoshima) Mutation via Hovey twin cotorsion pairs and model structures in extriangulated categories


2016

2016-12-13 Jonas Hedman (Uppsala) 2-Categories and Yoneda Lemma
2016-11-29 Hankyung Ko (Bonn) Cohomology of quantum groups at roots of unity
2016-11-15 Andrea Pasquali (Uppsala) Tensor products of n-complete algebras
2016-10-25 Elin Westin (Uppsala) Generalisation of the Brenner-Butler tilting theorem
2016-10-11 Jan-Erik Roos (Stockholm) On commutative Koszul and non-Koszul algebras
2016-09-27 Martin Herschend (Uppsala) Thick subcategories of n-cluster tilting subcategories
2016-09-13 Vanessa Miemietz (Norwich) Categorification and p-adic GL_n
2016-06-09 Gustav Hammarhjelm (Uppsala) On division algebras of dimension 2^n admitting C_2^n as a subgroup of their automorphism group
2016-06-07 Max Morin (Uppsala)  n-representation finite algebras and cluster roots
2016-05-17 Qimh Xantcha (Stockholm)  Polynomial functors on pointed categories
2016-04-19 Andreas Holmstrom (Ålesund) Tannakian symbols (or How to explain motives to high-school students)
2016-03-08 Elin Gawell (Stockholm) Centers of partly (anti-) commutative quiver algebras
2016-02-23 Yu Liu (Uppsala) Hearts of cotorsion pairs on exact categories
2016-02-02 Victoria Gould (York) Maximal subgroups of free idempotent generated semigroups
2016-01-19 Marco Mackaay (Algarve) Categorified quantum groups, representations and intertwiners

2015

2015-12-15 Vladimir Tkatjev (Linköping) Hsiang algebras
2015-12-08 Tobias Kildetoft (Uppsala) Decomposition of certain tensor products and character formulas for representations of algebraic groups
2015-11-24 Terry Gannon (Alberta/Karlstad) Mathieu Moonshine
2015-11-10 Naihong Hu (Shanghai) Loewy Filtration and Quantum de Rham Cohomology
2015-10-20 Ketil Tveiten  (Uppsala) Mutation of various things related to mirror symmetry for del Pezzo surfaces
2015-10-06 Markus Schmidmeier (Boca Raton) A Swiss Cheese type Theorem for linear operators with two invariant subspaces
2015-09-22 Aaron Chan (Uppsala) Curves on Riemann surfaces and complexes of Brauer graph algebras
2015-09-01 Fatma Al-Kharousi (Muscat) Studies in semigroups of contraction mappings of a finite chain
2015-08-18 Kevin Coulembier (Ghent) Ringel duality for parabolic category O
2015-06-02 Laertis Vaso (Uppsala) n-cluster tilting modules over quotients of path algebras of type A
2015-05-12 Benjamin Steinberg (New York) The representation theory of the full transformation monoids
2015-05-05 Peter Russell (Montreal) Actions of finite and multplicative groups on affine spaces
2015-04-28 Volodymyr Mazorchuk (Uppsala) Representations of generalized symmetric groups
2015-04-21 Vladimir Tkatjev (Linköping) Non-associative algebras of minimal cubic cones
2015-04-14 Peter Joergensen (Newcastle) Generalised friezes and a modified Caldero-Chapoton map depending on a rigid object
2015-03-24 Osamu Iyama (Nagoya) Higher preprojective algebrars and Cohen-Macaulay representations
2015-03-17 Noriyuki Abe (Hokkaido/Paris) Loewy series of parabolically induced G_1-modules
2015-03-03 Petter Andreas Bergh (Trondheim) n-angulated caegories
2015-02-17 Hanno Becker (Bonn) Models for singularity categories and applications to knot homology
2015-02-03 Juergen Fuchs (Karlstad)  Defects and symmetries in three-dimensional topological field theories

2014

2014-12-09 Olga Bershteyn (Copenhagen) Quantum groups and noncommutative analysis on quantum Hermitian symmetric spaces
2014-11-25 Martin Herschend (Uppsala) 2-representation finite algebras and tilting for one dimensional hypersurfaces
2014-11-04 Alessandro Oneto (Stockholm) Power ideals: from Fröberg conjecture to fat points
2014-10-21 Aaron Chan (Uppsala) Tilting theory of Brauer graph algebras
2014-09-30 Lilit Martirosyan (San Diego) The representation theory of the exceptional Lie superalgebras F(4) and G(3).
2014-09-16 Walter Mazorchuk (Uppsala) Dual projection functors in type A
2014-09-02 Isac Heden (Basel) The group of Cremona transformations generated by linear maps and the standard involution
2014-05-27 Alexander Stolin  (Göteborg) Classification of quantum groups and Lie bialgebra structures on sl(n,F): Relations with Brauer group
2014-05-13 Ornella Greco  (Stockholm) Syzygies of the Veronese modules
2014-04-29 Djalal Mirmohades (Uppsala) Simplicial structure on complexes
2014-04-08 Vanessa Miemietz (Norwich) Morita theory for finitary 2-categories
2014-03-25 Love Forsberg (Uppsala) Effective representation of truncated path semigroups
2014-03-11 Benjamin Nill (Stockholm) Combinatorial challenges of toric Fano varieties
2014-02-18 Olivier Mathieu (Lyon) Is it possible to classify all Z^N-graded Lie algebras?
2014-02-04 Jonathan Nilsson (Uppsala) The zoo of Lie algebra modules

2013

2013-12-10 Kevin Coulembier (Uppsala) Bott-Borel-Weil theory for Lie superalgebras
2013-11-26
Erik Darpö (Västerås) Self-injective n-representation-finite algebras
2013-11-12
Alexander Berglund (Stockholm) Koszul duality in algebraic topology
2013-10-15
Kevin Coulembier (Uppsala) Bott-Borel-Weil theory for Lie algebras
2013-10-01
Ivan Martino (Stockholm) The Ekedahl invariants for finite group
2013-09-17
Martin Herschend (Uppsala) Higher dimensional Auslander-Reiten theory
2013-09-06
Lucy Moser-Jauslin (Dijon) Some rational exotic affine threefolds and their automorphism groups
2013-09-03
Marco Mackaay (Algarve) The sl(N) web categories and categorified skew Howe duality
2013-06-04
Brendan Frisk Dubsky (Uppsala) Classification of simple complex weight modules with finite-dimensional weight spaces over the Schrödinger algebra
2013-05-21
David Rydh (Stockholm) Criteria for algebraicity and coherence
2013-05-07
Isac Heden (Uppsala) Algebraic G_a-actions on complex affine threefolds
2013-04-16
Martin Blomgren (Uppsala) Categorical homotopy theory and fibrations
2013-03-26
Axel Hultman (Linköping) Ubiquity of Schubert varieties defined by inclusions
2013-03-05
Vanessa Miemietz (Norwich) Affine Cellularity of Khovanov-Lauda-Rouquier algebras in type A
2013-02-26
Anne-Laure Thiel (Uppsala) Categorification of extended Hecke algebra and quantum Schur algebra of affine type A
2013-02-12 Ganna Kudryavtseva (Ljubljana) Quantales, inverse semigroups and etale groupoids
2013-02-05 Qimh Xantcha (Uppsala) On extensions of polynomial functors
2013-01-22 Linh Cao Huy (Uppsala) Castelnuovo-Mumford regularity of Tor-modules

2012

2012-12-04 Matthias Schramm (Uppsala) Gelfand model for the Brauer algebra in the semisimple case
2012-11-27 Joanna Meinel (Bonn/Uppsala) Primitive Ideals of Generalized Weyl Algebras
2012-11-13 Hjalmar Rosengren (Göteborg) Three-coloured chessboards
2012-10-30 Brendan Frisk Dubsky (Uppsala) Classification of the two-dimensional real commutative division algebras via the method of double sign decomposition
2012-10-23 Victor Ufnarovski (Lund) Combinatoric in words and its applications
2012-09-18 Seidon Alsaody  (Uppsala) Induced group actions and finite dimensional real division algebras
2012-09-11 Henning Haahr-Andersen (Århus) Quantum groups with partially divided powers
2012-06-05 Anna-Louise Grensing (Bielefeld) Monoids of projection functors
2012-05-31 Love Forsberg (Uppsala) Effective representations of Hecke-Kiselman monoids of type A
2012-05-22 Emilie Wiesner (Ithaca) Whittaker modules for Lie superalgebras
2012-05-08 Kaiming Zhao (Wilfrid Laurier University, Waterloo) Irreducible representations of the Virasoro algebra
2012-03-27 Martin Bridson (Oxford/Mittag-Leffler Institute) Rigidity and automorphisms of surfaces and free groups
2012-03-22 Erik Darpö (Nagoya) The Loewy length of a tensor product of modules of a dihedral 2-group
2012-02-28 Peter Kroppholler (Glasgow) Generic open subsets of spheres and applications to the Bieri-Neumann-Strebel invariant
2012-02-21 Guillaume Tomasini (Strasbourg) Dual pair correspondence for weight modules
2012-02-07 Ganna Kudryavtsevsa (Ljubljana) On Stone duality and its non-commutative generalizations

2011

2011-11-22 Carel Faber (Stockholm)  Modular forms and the cohomology of moduli spaces
2011-11-15
Vasyl Ostrovskyy (Kyiv) On Hilbert representations of partially ordered sets
2011-11-01
Luis Enrique Ramirez (Sao Paulo/Uppsala) Combinatorics of sl(3)-modules
2011-10-11
Ramon Horvath (Uppsala) On A_{\infty} algebras
2011-09-27
Aslak Buan (Trondheim) From triangulated categories to module categories via localisation
2011-05-31
Robin Kastberg (Uppsala) On induced modules over the full transformation monoid
2011-05-24
Jaroslaw Wisniewski (Warsaw) Differentials of Cox rings: Jaczewski's theorem revisited
2011-05-17
Benjamin Steinberg (Ottawa)  The representation theory of finite monoids
2011-04-12 
Wojciech Chacholski (Stockholm) Symmetries and deformations of finite simple groups
2011-04-05 Frank Sottile
(College Station) Orbitopes
2011-03-29 Qimh Xantcha (Stockholm) Polynomial functors
2011-03-08
Sarah Witherspoon (College Station) Support varieties and representation type
2011-02-15 Isac Hedén (Uppsala) Russell's hypersurface from a geometric point of view
2011-01-13 Karin Nilsson (Uppsala) Generation of the classical groups SO(4) and SO(8) by means of unit quaternions and unit octonions

2010

2010-12-14 Veronica Crispin Quinonez (Uppsala) The Ratliff-Rush operation on an ideal
2010-11-23
Paul Martin (Leeds) Decomposition numbers for Brauer algebras
2010-11-09
Karin Baur (Zuerich) A frieze pattern determinant
2010-10-26
Martin Herschend (Nagoya) 2-representation-finite algebras
2010-10-05
Qimh Xantcha (Stockholm) Polynomial maps
2010-09-21
Catharina Stroppel (Bonn) 3j-symbols and categorification
2010-09-07
Joseph Chuang (London) A dual approach to representations of symmetric groups
2010-08-31
Vanessa Miemietz (Norwich) The extension algebra of GL_2
2010-06-01
Seidon Alsaody (Uppsala) Generalisations of the algebraic theory of connective segmentation
2010-06-01 Rune Suhr (Uppsala) Triality
2010-05-18 
Djalal Mirmohades (Uppsala) N-complexes
2010-05-04
Semyon Konstein (Moscow) An example of simple Lie superalgebra with several invariant (nondegenerate symmetric) bilinear forms
2010-04-06
Maria Gorelik (Rehovot) On an analogue of Macdonald identities
2010-03-23 
Boris Shapiro (Stockholm) On algebras counting spanning forests and trees

2009

2009-12-15 Sandra Di Rocco (Stockholm) Toric polarized fibrations and Cayley polytopes
2009-11-03
Karl-Heinz Fieseler (Uppsala) The cylinder over Russel's hypersurface
2009-10-27
Erik Darpö (Oxford University) Four-dimensional power-commutative real division algebras
2009-10-20 Björn Selander (Uppsala) On Giraud's non-abelian cohomology
2009-10-06 Catharina Stroppel (Bonn) Generalised Khovanov algebras
2009-09-29 Punita Batra (Allahabad) A Problem related to Derivations of a Laurent Polynomial ring and Modules over pre-exp-polynomial Lie algebras
2009-09-15 Volodymyr Mazorchuk (Uppsala) Describing supports of weight modules
2009-06-02 Love Forsberg (Uppsala) Four-dimensional absolute valued algebras
2009-05-26 Vyacheslav Furtorny (Sao Paulo) Structure of induced modules for Affine Kac-Moody algebras
2009-05-12 Ernst Dieterich (Uppsala) Real division algebras, restricted quiver representations, and Euclidean configurations
2009-04-07 Ekaterina Orekhova (Uppsala) Simple weight q(2)-modules
2009-03-31 Erik Darpö (Uppsala) The transformation algebra of a division algebra
2009-03-17 Johan Alm (Uppsala University) Infinitesimal extensions of Hirzebruch surfaces
2009-03-13 Martin Herschend (Nagoya) Solution to the Clebsch-Gordan problem for string algebras
2009-03-03 Daniel Larsson (Uppsala ) Moduli of Lie algebras as Deligne-Mumford stacks
2009-02-17 Isac Heden (Uppsala) Russell's hypersurface from a geometric point of view
2009-02-03 Wojciech Chacholski (Stockholm) Cellularity of groups

2008

2008-11-11 Rowena Paget (Canterbury) Brauer algebras and Schur-Weyl dualities
2008-10-28 Johan Kåhrström (Uppsala) Kostant's problem and parabolic subgroups
2008-10-14 Vanessa Miemietz (Oxford) Schur algebras for GL_2
2008-09-30 Erik Darpö (Uppsala) On the representation ring of the polynomial algebra over a perfect field
2008-09-16 Karl-Heinz Fieseler (Uppsala) Tensor product of Hodge-Riemann modules
2008-09-02 Volodymyr Mazorchuk (Uppsala) Gelfand models
2008-05-27 Daniel Skog (Uppsala) Isometrier i Poincarés halvplansmodell
2008-05-26 Antoine Durdek (Uppsala) Simple weight sl(2)-modules and their tensor products
2008-05-20 Valentina Chapovalova (Uppsala) Decomposition of Certain S_n-modules into Specht Modules
2008-03-18 Johan Kåhrström (Uppsala) A New Approach to Kostant's Problem

2007

2007-18-12 Martin Herschend (Uppsala) On the representation rings of quivers of exceptional Dynkin type
2007-11-20 Sergiy Ovsienko (Kyiv) On the notion of a noncommutative order
2007-11-06 Oeyvind Soelberg (Trondheim)  Koszul theory for finite dimensional algebras
2007-10-23 Erik Darpö (Uppsala) Classification of pairs of rotations in finite-dimensional 
2007-10-09 Daniel Larsson (Uppsala) Moduli and deformations of Lie algebras
2007-09-25 Amy Glen (Montréal) Episturmian words: extremal properties and quasiperiodicity
2007-09-11 Johan Kåhrström (Uppsala) Tensoring with infinite-dimensional modules in O_0
2007-08-23 Ahmad Haghany (Isfahan) Endomorphism rings of semiprojective modules
2007-06-05 Anna Torstensson (Stockholm) Conjugacy classes in finite groups
2007-05-15 Alex Martsinkovsky (Boston)  Tails and Stable Homotopy Theory of Modules
2007-04-24 Gustaf Jonzon (Uppsala) The universal covering of the twice punctured plane
2007-04-17 Isac Heden (Uppsala) A C^3-like threefold which is not C^3
2007-03-20 Daniel Mondoc (Stockholm) Structurable algebras and Kantor triple systems
2007-03-13 Serge Ovisneko (Kyiv) Some finiteness statements for representations of gl_n
2007-02-27 Elizabeth Weldekidan (Uppsala) Perfect Codes and a construction of Golay Codes
2007-02-06 Björn Selander (Uppsala) Galois action on three-point G-covers of the Riemann sphere and classification of branched covers in characteristic p

2006

2006-12-12 Johan Kåhrström (Uppsala) On a nice hypergeometic identity
2006-11-07 Volodymyr Mazorchuk (Uppsala)  The idea of categorification for representation theory
2006-10-24 Ganna Kudryavtseva (Kyiv) Enlarging  a category by partial morphisms
2006-09-19 Catharina Stroppel (Glasgow)  Dynkin diagrams appear not only in Lie theory!
2006-05-16 Viacheslav Rabanovych (Kyiv) On sums of idempotent matrices and related questions
2006-05-09 Martin Herschend (Uppsala) Tensor Products on Quiver Representations
2006-04-25 Erik Darpö (Uppsala) Vector product algebras over general ground fields
2006-03-28 Jonas Hartwig (Göteborg) Ambiskew polynomial rings with Hopf structure
2006-03-14 Victor Maltcev (Kyiv) Representations of variants of semigroups

2005

2005-12-20 Karin Erdmann (Oxford)  Tilting modules for GL(3) over characteristic 2
2005-11-29 Anders Frisk (Uppsala) The category O for the queer Lie superalgebra q(n)
2005-11-15 Ganna Kudryavtseva (Kyiv) L- and R-cross-sections in the Brauer semigroup
2005-11-01 Karl-Heinz Fieseler (Uppsala) Rings of invariants and rings of regular functions
2005-10-11 Volodymyr Mazorchuk (Uppsala)  The category of linear complexes
2005-09-27 Martin Herschend (Uppsala) In which dimensions does a division algebra over a given ground field exist?
2005-09-13 Björn Selander (Uppsala) Kummer and Artin-Schreier theory formulated in terms of etale cohomology, with some applications to covers of curves
2005-08-23 Serge Ovsienko (Kyiv) Matrix Jordan algebras and their representations
2005-06-14 Catharina Stroppel (Glasgow) From Serre's functor to Serre functors in representation theory
2005-06-07 Mark Haiman (Berkeley) A combinatorial formula for Macdonald polynomials
2005-06-02 Jose Antonio Cuenca Mira (Malaga) On composition and absolute valued algebras
2005-05-17 Volodymyr Nekrashevych (Bremen) Iterated monodromy groups
2005-05-03 Magnus Hellgren (Uppsala) Invariant theory of Z_p over fields of characteristic p
2005-04-26 Johan Kåhrström (Uppsala) A brief introduction to buildings
2005-04-19 Anders Frisk (Uppsala) Finitistic dimension of standardly stratified algebras
2005-04-15 Francois Bergeron (Montreal) Invariants of reflection groups, and coinvariant spaces
2005-04-05 Martin Herschend (Uppsala) Coverings and the Clebsch-Gordan problem for quiver representations
2005-03-22 Jonas Hartwig (Göteborg) Weight modules over twisted generalized Weyl algebras
2005-03-15 Pavlo Kolomiiets (Kyiv) On some generalization of Schubert varieties
2005-03-08 Volodymyr Mazorchuk (Uppsala) Quasi-hereditary and properly stratified algebras
2005-03-01 Erik Darpö (Uppsala) Vector products and real division algebras
2005-02-22 Galyna Tsyaputa (Kyiv) Transformation semigroups under sandwich multiplication
2005-02-15 Ernst Dieterich (Uppsala) A survey on real division algebras
2005-02-08 Karl-Heinz Fieseler (Uppsala) Kombinatorisk Snitthomologi för polytop
2005-02-01 Serge Ovsienko  (Kyiv) Galois algebras

2004

2004-12-09 Yuriy Drozd  (Kyiv) Derived categories of modules and coherent sheaves
2004-11-29 Daniel Simson  (Torun) Artin's problem on skew field extensions and hereditary artinian rings with two connected AR-components
2004-01-18 Andreas Juhl  (Uppsala) Verma modules and conformally invariant differential operators
2004-06-01 Serge Ovsienko  (Kyiv) Commutative subalgebras of non-commutative algebras
2004-05-27 Orlando Villamayor  (Madrid) An introduction to constructive resolution of singularities
2004-05-25 Henning Haahr Andersen  (Ã…rhus) Cohomology of line bundles
2004-04-27 William Crawley-Boevey  (Leeds) Multiplicative preprojective algebras and the Deligne-Simpson problem
2004-03-15 Claus Michael Ringel  (Bielefeld) Subgroups of finite abelian groups
2004-01-30 Catharina Stroppel  (Ã…rhus) Tangles, Temperley-Lieb and projective functors

2003

2003-12-17 Birge Huisgen-Zimmermann  (Santa Barbara) Moduli spaces for finite dimensional representations
2003-12-10 Aidan Schofield  (Bristol) Noncommutative moduli spaces
2003-11-11 Vitaliy Sushchanskyy  (Kyiv/Gliwice) Groups acting on rooted trees
2003-10-24 Idun Reiten  (Trondheim) Modules of infinite length over finite dimensional algebras
2003-10-22 Anders Frisk  (Uppsala) Properly stratified algebras and tilting modules
2003-10-02 Gottfried Barthel  (Konstanz) Pythagorean Quadrisection of Squares and Rational Points on Certain Elliptic Curves
2003-09-12 Anton Cox  (London) Tilting tensor products and symmetric groups
2003-05-22 Serge Ovsienko  (Kyiv) Quasi-hereditary algebras, coalgebras over a category and A_\infty-categories
2003-05-15 Steffen Koenig (Leicester) Polynomial functors in prime degree
2003-05-08 Erik Darpö (Uppsala) Classification of the real flexible division algebras
2003-05-07 Alex Martsinkovsky  (Boston) A new approach to noncommutative Serre duality
2003-05-06 Martin Herschend (Uppsala) Solution of the Clebsch-Gordan problem for Kronecker representations
2003-03-14 Oleksandr Khomenko (Freiburg) Groebner basis of ideals in algebras with PBW basis and its applications
2003-02-28 Catharina Stroppel (Leicester) Categorifications of Hecke Algebra Quotients

2002

2002-12-17 Jean-Paul Brasselet (Marseille) Characteristic Classes of singular Varieties
2002-12-13 Marcos Soriano (Bielefeld)  Producing "Big" Ext-Groups for Weyl Modules over GL
2002-12-06 Lars Lindberg (Uppsala) Dissident maps and real division algebras
2002-11-29 Lyudmyla Turowska (Göteborg) Decomposition of scalar matrix into a sum of idempotents
2002-10-01 Alison Parker (Oxford) On the Weyl filtration dimension of the induced modules for a linear algebraic group
2002-09-12 Reidun Twarock (London) New algebraic and group theoretical structures related to quasicrystals 
2002-08-13 Yuriy Samoilenko (Kyiv) Algebras generated by projections, their representations and applications 
2002-05-08 Anna Kudryavtseva  (Kyiv) Nilpotent transformation semigroups and their groups of automorphisms 
2002-05-03 Alex Martsinkovsky (Boston) Noncommutative Sheaf Cohomology over Koszul Quiver Algebras 
2002-04-18 Steffen König (Leicester) Repeating patterns in decomposition matrices of general linear groups 
2002-02-19 Olexandr Khomenko (Freiburg) Some applications of Gelfand-Zetlin Modules 
2002-02-13  Shoetsu Ogata (Erlangen) Frobenius splitting on toric varieties 
2002-02-12  Shoetsu Ogata (Erlangen) On generator of ideals defining toric varieties

2001

2001-12-12 Jan Stevens (Göteborg) Semistable K3-surfaces and icosahedral symmetry 
2001-12-07 Marcos Soriano (Ã…rhus) The structure of generic Iwahori-Hecke algebras 
2001-11-26 Lyudmyla Turowska (Göteborg) Wild problems in the theory of *-representations of *-algebras  
2001-11-02 Björn Dundas (Trondheim) Recent trends and results in algebraic K-theory: a survey
2001-10-12 Volodymyr Mazorchuk (Uppsala) Certain functors, associated with localizations of U(g)
2001-08-31 Ludger Kaup (Konstanz) Homology of Lower-dimensional Toric Varieties. 
2001-03-09 Florian Berchtold (Konstanz) Morphisms between toric varieties

2000

2000-08-30 Ludger Kaup (Konstanz) Simplicial fans and cohomology
2000-05-23 Per Salberger (Chalmers) Aritmetik för toriska varieteter


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