Welcome to the homepage of the MAXIMALS algebra seminar, at the University of Edinburgh. The seminar represents the interests of all Edinburgh faculty working in algebra and number theory, and is currently being coordinated by Natalia Iyudu. We meet regularly on Tuesdays in the James Clerk Maxwell Building, Room 5323, from 2:053:55pm. The first hour typically consists of an introduction to the proper research talk which takes place 3:053:55pm. Exceptions are noted below.
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Upcoming MAXIMALS events at University of Edinburgh

EDGE/MAXIMALS: Jørgen Rennemo (University of Oslo)  TBC
6th November 2018, 2:00pm to 3:00pm TBA  Show/hide abstract 
EDGE/MAXIMALS: Francesco Sala (IPMU)  TBC
27th November 2018, 2:00pm to 3:00pm TBA  Show/hide abstract 
MAXIMALS: Ian Le (Perimeter Institute)  TBC
4th December 2018, 2:00pm to 3:00pm TBA  Show/hide abstract
Upcoming MAXIMALS events at HeriotWatt
Past MAXIMALS events at University of Edinburgh

MAXIMALS: Uzi Vishne (BarIlan University)  Locally central simple algebras
17th July 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Valerio Toledano Laredo (Northeastern University) Yangians, quantum loop algebras and elliptic quantum groups
19th June 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Joao Faria Martins (University of Leeds) Categorifications of the KZconnection
5th June 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Adrien Brochier (Hamburg University) Towards a quantum RiemannHilbert correspondence
29th May 2018, 3:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Noah Snyder (Indiana University) Exceptional Fusion Categories
29th May 2018, 2:05pm to 2:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Olivier Schiffmann (Université Paris Sud)  Cohomological hall algebra of coherent sheaves on a smooth projective curve
22nd May 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Kayvan Nejabati Zenouz (University of Edinburgh)  HopfGalois Theory and the YangBaxter Equation
15th May 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Stefan Kolb (University of Newcastle)  Braided module categories via quantum symmetric pairs
8th May 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Michael Groechenig (Freie Universität Berlin)  padic integration for the Hitchin system
1st May 2018, 3:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Thomas Nevins (University of Illinois UrbanaChampaign)  Cohomology of quiver varieties and other moduli spaces
1st May 2018, 2:05pm to 2:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Omar Leon Sanchez (University of Manchester)  The DixmierMoeglin equivalence: a differential and a modeltheoretic version.
24th April 2018, 2:05pm to 3:55pm JCMB 1501  Show/hide abstract 
MAXIMALS: Martina Balagovic (Newcastle University)  The affine VW supercategory
17th April 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Jan Grabowski (Lancaster University)  Recovering automorphisms of quantum spaces
27th March 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Jamie Judd (King's College London)  Tropical critical points of the superpotential for the flag variety in type A.
21st March 2018, 2:05pm to 2:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Daniele Valeri (Tsinghua University)  Algebraic structures arising from physics
13th February 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Clark Barwick (University of Edinburgh)  Exodromy
6th February 2018, 2:05pm to 3:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Karin Baur (University of Graz)  Dimers with boundary, associated algebras and module categories
30th January 2018, 3:05pm to 3:55pm JCMB 5323  Show/hide abstract 
Joint UoEHW Maximals seminar: Collin Bleak (St. Andrews)  Generalised PingPong Lemmas, and the group of PL homeomorphisms of the unit interval.
23rd January 2018, 3:05pm to 3:55pm James Clerk Maxwell Building, Edinburgh EH9, UK, room 5323  Show/hide abstract 
Joint UoEHW Maximals seminar: Yuri Bazlov (Manchester)  Hcross products
23rd January 2018, 2:05pm to 2:55pm James Clerk Maxwell Building, Edinburgh EH9, UK, room 5323  Show/hide abstract 
Joint EDGEMAXIMALS: Peter Samuelson (University of Edinburgh)  The Hall algebra of the Fukaya category of a surface
16th January 2018, 3:05pm to 3:55pm JCMB 5323  Show/hide abstract 
Joint EDGEMAXIMALS: Peter Samuelson (University of Edinburgh)  The Hall algebra of an elliptic curve
16th January 2018, 2:05pm to 2:55pm JCMB 5323  Show/hide abstract 
MAXIMALS: Richard Timoney, Associative universal enveloping triples for Jordan triples
12th December 2017, 3:05pm to 3:55pm James Clerk Maxwell Building, Edinburgh EH9, UK, seminar room 5323  Show/hide abstract 
MAXIMALS: Richard Timoney, A brief survey of Jordan triples
12th December 2017, 2:05pm to 2:55pm James Clerk Maxwell Building, Edinburgh EH9, UK, seminar room 5323  Show/hide abstract 
MAXIMALS: Yuri Bahturin, Growth functions and embeddings of algebras
5th December 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Yuri Bahturin, Associative and Lie algebras defined by generators and relations
5th December 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMLS: Jessica Sidman, Barandjoint frameworks: Stresses and Motions
4th December 2017, 3:05pm to 3:55pm James Clerk Maxwell Building, Edinburgh EH9, UK, room 6201  Show/hide abstract 
MAXIMALS: Lewis Topley, The orbit method for Poisson orders
28th November 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Lewis Topley  The orbit method for Poisson orders
28th November 2017, 2:05pm to 2:55pm Seminar room, JCMB 5323  Show/hide abstract 
MAXIMALS: Andrea Santi, talk title  On a class of ternary algebras
21st November 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, Seminar room 5323  Show/hide abstract 
MAXIMALS: Andrea Santi, On a class of ternary algebras
21st November 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, Seminar room 5323  Show/hide abstract 
MAXIMALS: Angus Macintyre, Exponential algebra and its relevance to analysis
14th November 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Angus Macintyre, Exponential algebra and its relevance to analysis
14th November 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, Seminar room 5323  Show/hide abstract 
MAXIMALS: Gabor Elek, Almost commuting matrices
7th November 2017, 3:05pm to 3:55pm Seminar Room, JCMB 5323  Show/hide abstract 
MAXIMALS: Gabor Elek, Almost commuting matrices
7th November 2017, 2:05pm to 2:55pm Seminar Room, JCMB 5323  Show/hide abstract 
MAXIMALS: Stephane Launois  Total positivity and quantum algebras
31st October 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, Seminar Room 5323  Show/hide abstract 
MAXIMALS: Stephane Launois, Total positivity and quantum algebras
31st October 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, Seminar room 5323  Show/hide abstract 
MAXIMALS: Dom Hipwood  Blowing up a noncommutative surface
17th October 2017, 3:05pm to 3:55pm Seminar Room, JCMB 5323  Show/hide abstract 
MAXIMALS: Dom Hipwood  Introduction to noncommutative projective geometry
17th October 2017, 2:05pm to 2:55pm Seminar Room, JCMB 5323  Show/hide abstract 
MAXIMALS: Stanislav Shkarin, Automaton algebras versus finite Groebner basis
10th October 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Stanislav Shkarin, pretalk: Intermediate growth via Groebner basis
10th October 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Kevin Tucker, talk  Bertini Theorems for Fsignature
3rd October 2017, 3:05pm to 3:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Kevin Tucker, pretalk 'An introduction to Finvariants'
3rd October 2017, 2:05pm to 2:55pm JCMB, Edinburgh, United Kingdom, seminar room 5323  Show/hide abstract 
MAXIMALS: Andrea Appel  The isomorphism between classical and quantum sl(n)
26th September 2017, 3:05pm to 3:55pm Seminar room JCMB 5323  Show/hide abstract 
MAXIMALS: Adrea Appel  The Yangian and the Capelli identities for gl(n) and sl(n)
26th September 2017, 2:05pm to 2:55pm Seminar room JCMB 5323  Show/hide abstract 
MAXIMALS: Greg Stevenson  "Noncrossing partitions as lattices of localizations"
19th September 2017, 3:05pm to 3:55pm video conference room 5323, JCMB  Show/hide abstract 
MAXIMALS: Greg Stevenson  "Quivers, their derived categories, and lattices of subcategories"
19th September 2017, 2:05pm to 2:55pm video conference room 5323, JCMB  Show/hide abstract 
Theo JohnsonFreyd (Perimeter Institute)  The Moonshine Anomaly
19th July 2017, 4:00pm to 5:00pm  Show/hide abstract 
MAXIMALS Seminar  Travis Schedler: Poisson (co)homology via Dmodules
23rd May 2017, 2:00pm to 3:00pm Seminar room, JCMB 5323  Show/hide abstract 
GEARS Seminar  Travis Schedler: Poisson traces, Dmodules, and symplectic resolutions II
22nd May 2017, 4:00pm to 5:00pm Seminar room, JCMB 5323  Show/hide abstract 
GEARS Seminar  Travis Schedler: Poisson traces, Dmodules, and symplectic resolutions I
22nd May 2017, 2:30pm to 3:30pm Seminar room JCMB 5323  Show/hide abstract 
David Ssevviiri (University of Makerere): Completely prime modules and 2primal modules
8th May 2017, 3:00pm to 4:00pm 4325B  Show/hide abstract 
MAXIMALS: Brent Pym  "Multiple zeta values in deformation quantization"
18th April 2017, 3:10pm to 4:00pm JCMB 5323 (video conference room)  Show/hide abstract 
MAXIMALS: Brent Pym  "Introduction to Kontsevich's quantization formula"
18th April 2017, 2:10pm to 3:00pm JCMB 5323 (video conference room)  Show/hide abstract 
MAXIMALS: Elena Gal  "A geometric approach to Hall algebra"
4th April 2017, 3:10pm to 4:10pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS: Adam Gal  "Base change and categorification"
4th April 2017, 2:10pm to 3:00pm video conference room 5323, JCMB  Show/hide abstract 
MAXIMALS: Leandro Vendramin  Settheoretical solutions of the YangBaxter equation
28th March 2017, 2:10pm to 3:00pm  Show/hide abstract 
MAXIMALS: Pieter Belmans  Construction of noncommutative surfaces of rank 4
21st March 2017, 3:10pm to 4:00pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS: Pieter Belmans Exceptional collections, mutations and Serre functors
21st March 2017, 2:10pm to 3:00pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS: Bart Van Steirteghem  A characterization of the weight monoids of smooth affine spherical varieties
14th March 2017, 3:10pm to 4:10pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS: Bart Van Steirteghem  Representation theory and combinatorial invariants of algebraic varieties
14th March 2017, 2:10pm to 3:00pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS: Iva Halacheva (Lancaster)  The odd Brauer category and the periplectic Lie superalgebra
14th February 2017, 3:10pm to 4:00pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS (Preseminar):Iva Halacheva (Lancaster)  SchurWeyl duality for gl(n) and beyond
14th February 2017, 2:10pm to 3:00pm video conference room (5323) JCMB  Show/hide abstract 
MAXIMALS  Ben Davison: Hidden properness and KacMoody algebras
7th February 2017, 3:10pm to 4:10pm  Show/hide abstract 
MAXIMALS: Ben Davison  Hunting for BPS algebras
7th February 2017, 2:10pm to 3:10pm  Show/hide abstract 
Joint EMPGMAXIMALS: Bart Vlaar (York)  TBA
1st February 2017, 2:30pm to 3:30pm ICMS New Seminar Room 
MAXIMALS  Simon Crawford. Singularity categories of deformations of Kleinian singularities
31st January 2017, 3:00pm to 4:00pm 5323 JCMB (next to common room)  Show/hide abstract 
Joint UoE&HW MAXIMALS: Ben Martin (Aberdeen)  Complete reducibility and geometric invariant theory
25th January 2017, 3:10pm to 4:00pm ICMS Lecture Theatre  Show/hide abstract 
Joint UoE&HW MAXIMALS: Armando Martino (Southampton)  The Lipschitz Metric on Culler Vogtmann Space and Automorphisms of Free Groups
25th January 2017, 2:10pm to 3:10pm ICMS Lecture Theatre  Show/hide abstract 
MAXIMALS: José FigueroaO'Farrill (Edinburgh) Filtered deformations in Algebra, Geometry and Physics
6th December 2016, 3:10pm to 4:00pm JCMB 6206  Show/hide abstract 
MAXIMALS(preseminar): José FigueroaO'Farrill (Edinburgh) Filtered deformations in Algebra, Geometry and Physics
6th December 2016, 2:10pm to 3:00pm JCMB 6206  Show/hide abstract 
MAXIMALS: Mehdi Aaghabali (Edinburgh)  "Left algebraic division rings".
29th November 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS (preseminar): Mehdi Aaghabali (Edinburgh)  "Commutators contain important information about division rings".
29th November 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Kevin De Laet (Antwerp) Quantum algebras with an action of a finite group
15th November 2016, 4:10pm to 5:00pm JCMB 1601  Show/hide abstract 
MAXIMALS (preseminar): Kevin De Laet (Antwerp) A short introduction to noncommutative projective geometry
15th November 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Dave Benson (Aberdeen)  Module categories for finite groups, finite group schemes, and finite supergroup schemes.
8th November 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS(preseminar): Dave Benson (Aberdeen)  Module categories for finite groups, finite group schemes, and finite supergroup schemes.
8th November 2016, 3:10pm to 4:00pm JCMB 1501 
Joint EMPGMAXIMALS Seminar: Sanjaye Ramgoolam (Queen Mary)  Algebras, Invariants and GaugeString Duality.
25th October 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
Joint EMPGMAXIMALS Seminar(preseminar): Sanjaye Ramgoolam (Queen Mary)  Algebras, Invariants and GaugeString Duality.
25th October 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: David Jordan (University of Edinburgh)  A topological field theory in dimension four
18th October 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS (preseminar): David Jordan (University of Edinburgh)  Elementary representation theory, categorified
18th October 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Gwyn Bellamy (Glasgow) Symplectic resolutions of quiver varieties.
11th October 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS(preseminar): Gwyn Bellamy (Glasgow) Introduction to quiver varieties.
11th October 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Iordan Ganev (Vienna)  The wonderful compactification for quantum groups
4th October 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS(preseminar): Iordan Ganev (Vienna)  An introduction to the wonderful compactification
4th October 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Natalia Iyudu (University of Edinburgh) Sklyanin algebras via Groebner bases
27th September 2016, 4:10pm to 5:00pm JCMB 1501  Show/hide abstract 
MAXIMALS (preseminar): Natalia Iyudu (University of Edinburgh) Sklyanin algebras via Groebner bases
27th September 2016, 3:10pm to 4:00pm JCMB 1501  Show/hide abstract 
MAXIMALS: Alexey Petukhov (Manchester): Primitive ideals of U(sl(infinity))
7th September 2016, 3:00pm to 4:00pm 6206 JCMB  Show/hide abstract 
Sasha Shapiro (UC Berkeley/Toronto)  Cluster structure on quantum groups
19th July 2016, 3:00pm to 5:00pm JCMB 5327  Show/hide abstract 
Noah Snyder (IU Bloomington)  The exceptional knot polynomial
12th July 2016, 3:00pm to 4:00pm JCMB 6311  Show/hide abstract 
Sam Gunningham (UT Austin)  Induction and Restriction patterns in geometric representation theory
7th July 2016, 3:00pm to 5:00pm JCMB 5327  Show/hide abstract 
Andrea Appel (USC)  Quantum Groups, Monodromy, and Generalised Braided Categories
5th July 2016, 3:00pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Tom Braden (University of Massachusetts, Amherst)  Modular representation theory and hypertoric varieties.
28th June 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Noah Arbesfeld (Columbia University)  A geometric Rmatrix for the Hilbert scheme of points on a surface
21st June 2016, 3:00pm to 5:00pm  Show/hide abstract 
Johanna Hennig (Alberta)  Path algebras of quivers and representations of locally finite Lie algebras
15th June 2016, 3:00pm to 4:00pm 4325B  Show/hide abstract 
Gus Schrader (UC Berkeley)  Geometric Rmatrices, Yangians, and reflection equation algebras
15th June 2016, 11:00am to 1:00pm JCMB 5327  Show/hide abstract 
Peter Samuelson (Iowa State > University of Edinburgh) Kauffman bracket skein modules and double affine Hecke algebras
7th June 2016, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Maximals: Ulrich Thiel (Stuttgart) Finitedimensional graded algebras with triangular decomposition
24th May 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
MAXIMALS: Gwendolyn E. Barnes (HeriotWatt)  Nonassociative geometry in representation categories of quasiHopf algebras
17th May 2016, 2:00pm to 3:00pm JCMB 4312  Show/hide abstract 
Maximals: Dmitry Gurevich  Quantum matrix algebras and braided Yangians
26th April 2016, 3:10pm to 5:00pm JCMB 6206  Show/hide abstract 
Maximals: Stephane Gaussent (SaintEtienne)  Hovels and Hecke algebras
22nd March 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Tatiana GatevaIvanova (American University in Bulgaria, Sofia) Settheoretic solutions of the YangBaxter equation and related algebraic objects
15th March 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Sergey Malev (Edinburgh)  The images of noncommutative polynomials evaluated on matrix algebras.
8th March 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Robert Marsh (Leeds)  Twists of Pluecker coordinates as dimer partition functions
1st March 2016, 3:30pm to 4:30pm JCMB 5327  Show/hide abstract 
Maximals: Markus Reineke (Wuppertal)  "Geometry of DonaldsonThomas invariants of quivers"
23rd February 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
MAXIMALS: Sian Fryer (Leeds)  There And Back Again: A Localization's Tale
17th February 2016, 1:10pm to 2:00pm JCMB 6206  Show/hide abstract 
Maximals: Emily Cliff (Oxford)  Factorisation spaces and examples from Hilbert schemes
16th February 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Alberto Facchini (Padova)  KrullSchmidtRemak theorem, directsum decompositions of modules, directproduct decompositions of groups, Ggroups
9th February 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: CANCELLED
2nd February 2016, 3:10pm to 5:00pm JCMB 5327 
Maximals: Brendan Nolan (Kent)  A generalised DixmierMoeglin equivalence for quantum Schubert cells.
26th January 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Jacopo Gandini (Pisa)  On the set of orbits of a spherical subgroup on the flag variety
19th January 2016, 3:10pm to 5:00pm JCMB 5327  Show/hide abstract 
Maximals: Rishi Vyas (BenGurion University)  A noncommutative MatlisGreenleesMay equivalence
7th December 2015, 4:10pm to 5:00pm JCMB 4312  Show/hide abstract 
Maximals: Guido Pezzini (Erlangen)  Spherical subgroups of KacMoody groups
1st December 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Antonio Sartori (Freiburg)  Link invariants of type A and categorification.
24th November 2015, 3:10pm to 5:00pm JCBM 6311  Show/hide abstract 
Maximals: Daniel Tubbenhauer (Bonn)  (Singular) TQFT’S, link homologies and Lie theory
17th November 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Michel Van den Bergh (Hasselt)  Resolutions of determinantal varieties.
16th November 2015, 1:10pm to 2:00pm JCMB 5327  Show/hide abstract 
Maximals: Xin Fang (Cologne)  Linear degenerations of flag varieties
10th November 2015, 3:10pm to 5:00pm JCBM 6311  Show/hide abstract 
Maximals: Michael Ehrig (Bonn)  How to think of the good old Brauer algebra?
3rd November 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Hodge seminar: Sarah Zerbes (UCL)  Euler systems and the conjecture of Birch and SwinnertonDyer
2nd November 2015, 1:10pm to 2:00pm JCMB 5327  Show/hide abstract 
Maximals: Martina Lanini (Edinburgh)  Multiplicity formulae and moment graph modules.
27th October 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Tara Brendle (Glasgow)  Combinatorial models for mapping class groups
20th October 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Deke Zhao (Beijing Normal University at Zhuhai)  HattoriStallings traces
13th October 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Milen Yakimov (LSU)  Cluster structures on open Richardson varieties and their quantizations
6th October 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Wolfgang Soergel (Freiburg)  Graded Representation Theory and Motives
29th September 2015, 3:10pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Claire Amiot (Grenoble)  Derived invariants for surface algebras
17th September 2015, 2:00pm to 3:00pm JCMB 6206  Show/hide abstract 
GEARS: Claire Amiot (Institut Fourier, Grenoble): Cluster categories for algebras of global dimension 2 and clustertilting theory
15th September 2015, 3:00pm to 5:30pm ICMS  Show/hide abstract 
Maximals: Monica Vazirani (UC Davis)  Representations of the affine BMW algebra
14th September 2015, 4:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
ARTIN 45
11th September 2015, 1:00pm to 1:00pm JCMB 6206  Show/hide abstract 
Maximals: Theodore Voronov (Manchester)  Microformal geometry
2nd June 2015, 2:00pm to 3:00pm JCMB 4325B  Show/hide abstract 
Maximals: Charlie Beil (Bristol)  Smooth noncommutative blowups of dimer algebras and isolated nonnoetherian singularities
26th May 2015, 2:00pm to 3:00pm 6206 JCMB  Show/hide abstract 
Alissa Crans (Loyola Marymount University)  Crossed modules of racks
14th May 2015, 2:00pm to 3:00pm JCMB 6311  Show/hide abstract 
Arkady Vaintrob (University of Oregon)  Cohomological field theories related to singularities and matrix factorizations
2nd April 2015, 2:00pm to 3:00pm  Show/hide abstract 
Maximals: Alexey Petukhov (University of Manchester)  Twosided ideals of U(sl(oo))
31st March 2015, 3:00pm to 4:00pm JCMB 4325B  Show/hide abstract 
Maximals: Michael McBreen (IPFL Lausanne)  Mirror Symmetry for Hypertoric Varieties
17th March 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Misha Feigin (Glasgow)  On PBW subalgebras of Cherednik algerbras
10th March 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Maximals: Raf Bocklandt (Amsterdam)
3rd March 2015, 3:00pm to 5:00pm 
Maximals: Christian Korff (Glasgow)  YangBaxter algebras in quantum cohomology
24th February 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Pavel Safronov (Oxford)  Quantization of Hamiltonian reduction
19th February 2015, 3:00pm to 5:00pm JCMB 4325A  Show/hide abstract 
Maximals: Jack Jeffries (University of Utah)  How many invariants are needed to separate orbits?
3rd February 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Maximals: Cesar Lecoutre (Kent)  A Poisson GelfandKirillov problem in positive characteristic
27th January 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Maximals: Robert Laugwitz (Oxford)  Braided Drinfeld and Heisenberg doubles and TQFTs with defects
20th January 2015, 3:00pm to 5:00pm JCMB 4325B  Show/hide abstract 
Maximals: Richard Hepworth (Aberdeen)  A homology theory for graphs
13th January 2015, 3:00pm to 5:00pm JCMB  4325B  Show/hide abstract 
MAXIMALS: Bin Shu (East China Normal)
2nd December 2014, 4:10pm to 6:10pm JCMB 6311  Show/hide abstract 
MAXIMALS: Martin Kalck (Edinburgh): Spherical subcategories and new invariants for triangulated categories
25th November 2014, 3:00pm to 5:00pm JCMB 6311 
MAXIMALS: Rupert Yu (Reims)
18th November 2014, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
MAXIMALS: David Pauksztello (Manchester)
18th November 2014, 3:00pm to 4:00pm JCMB 6311  Show/hide abstract 
MAXIMALS: Arend Bayer (Edinburgh)
11th November 2014, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Karel Casteels (Kent)
4th November 2014, 3:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Christian Lomp and Paula Carvalho
28th October 2014, 3:00pm to 5:00pm JCMB 4319a 
Evgeny Feigin
30th September 2014, 3:00pm to 5:00pm JCMB Lecture Theatre A 
NBSAN meeting
21st July 2014, 1:00pm to 5:30pm Appleton 2.14  Show/hide abstract 
Andre LeRoy (University of Artois)
27th May 2014, 2:30pm to 3:30pm  Show/hide abstract 
Maria Chlouveraki (Versailles)
27th May 2014, 1:00pm to 2:00pm  Show/hide abstract 
Noah Snyder (IU Bloomington)
16th May 2014, 1:00pm to 3:00pm JCMB 6206 
Carl Mautner (MPIM Bonn)
13th May 2014, 3:00pm to 4:00pm JCMB 6311 
Dorette Pronk (Dalhousie)
22nd April 2014, 3:00pm to 5:00pm 
MAXIMALS: Alexey Sevastyanov (Aberdeen)
8th April 2014, 3:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: Elisa Gorla (Basel)
1st April 2014, 3:00pm to 5:00pm  Show/hide abstract 
Claudio Sibilia (ETH Zurich)
25th March 2014, 4:00pm to 5:00pm 
MAXIMALS: Iordan Ganev (UT Austin)
25th March 2014, 3:00pm to 4:00pm 
Hodge seminar: Ben Webster (U Virginia/Paris 6)
18th March 2014, 3:00pm to 5:00pm 
MAXIMALS: Felipe Rincon (Warwick)
4th March 2014, 3:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: Johanna Hennig (UCSD)
25th February 2014, 3:00pm to 5:00pm  Show/hide abstract 
Erez Sheiner (Bar Ilan)
14th February 2014, 12:00pm to 1:00pm  Show/hide abstract 
MAXIMALS: Greg Ginot (Paris 6)
11th February 2014, 3:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: Sian Fryer (Manchester)
4th February 2014, 3:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: Michael Wemyss (Edinburgh)
28th January 2014, 4:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: JeanMarie Bois (Kiel)
21st January 2014, 3:00pm to 5:00pm  Show/hide abstract 
MAXIMALS: David Gepner (Regensburg)
7th January 2014, 3:00pm to 5:00pm  Show/hide abstract 
Ghislain Fourier (Glasgow)
6th December 2013, 4:00pm to 5:00pm 
Anne Thomas (Glasgow)
6th December 2013, 3:00pm to 4:00pm 
Ines Henriques (Sheffield)
26th November 2013, 4:00pm to 5:00pm 
Emily Dufresne (Basel)
26th November 2013, 3:00pm to 4:00pm 
Tom Lenagan (Edinburgh)
19th November 2013, 3:00pm to 5:00pm 
David Jordan (Sheffield)
13th November 2013, 4:00pm to 5:00pm 
David Evans (Cardiff)
28th October 2013, 3:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Chris Dodd (Toronto)
25th October 2013, 4:00pm to 5:00pm JCMB 4312  Show/hide abstract 
Chris Dodd (Toronto)
24th October 2013, 4:00pm to 5:00pm JCMB 4312  Show/hide abstract 
Chris Dodd (Toronto)
23rd October 2013, 4:00pm to 5:00pm JCMB 4312  Show/hide abstract 
Chris Dodd (Toronto)
23rd October 2013, 2:00pm to 3:00pm JCMB 6311  Show/hide abstract 
Nick Gurski (Sheffield)
22nd October 2013, 3:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Joseph Chuang (City University London)
15th October 2013, 3:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Beeri Grenfeld (Bar Ilan)
8th October 2013, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Uzi Vishne (Bar Ilan)
8th October 2013, 3:00pm to 4:00pm JCMB 6311  Show/hide abstract 
Natalia Iyudu (Edinburgh)
1st October 2013, 4:00pm to 5:00pm JCMB 6311 
David Andrew Jordan (Edinburgh)
1st October 2013, 3:00pm to 4:00pm JCMB 6311 
Gwyn Bellamy (Glasgow)
24th September 2013, 3:00pm to 5:00pm JCMB 6311 
Stefan Kolb (Newcastle)
17th September 2013, 3:00pm to 5:00pm JCMB 6311 
Francois Petit (Edinburgh)
9th September 2013, 5:00pm to 6:00pm  Show/hide abstract 
Hendrik Suess (Edinburgh)
9th September 2013, 4:00pm to 5:00pm  Show/hide abstract 
Qendrim Gashi (Pristina, Kosovo)  Maximals
4th September 2013, 3:00pm to 5:00pm TBA  Show/hide abstract 
Vassily Gorbounov (Aberdeen)  joint with Geometry&Topology: Quantum cohomology and quantum groups
19th March 2013, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
MAXIMALS: Julien Bichon (ClermontFerrand): Hochschild homology of Hopf algebras and free YetterDrinfeld modules
12th March 2013, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
MAXIMALS: Alexander Engström (Aalto University, Helsinki, Finland): Powers of ideals
26th February 2013, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
MAXIMALS: Joseph Grant (Leeds): Derived autoequivalences and braid relations
19th February 2013, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
MAXIMALS: Zoe O'Connor (HeriotWatt): multiple Conjugacy Search Problem in Limit Groups
12th February 2013, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
MAXIMALS: Damien Calaque (ETH Zurich): Lie theory of closed embeddings
5th February 2013, 4:00pm to 5:00pm ICMS (15 South College Street)  Show/hide abstract 
MAXIMALS: Charlie Beil
10th December 2012, 4:00pm to 5:00pm 6206 JCMB  Show/hide abstract 
Kobi Kremnitzer (Oxford)
4th December 2012, 4:30pm to 5:30pm ICMS (15 South College Street)  Show/hide abstract 
Uli Kraehmer (Glasgow)
4th December 2012, 3:00pm to 4:00pm ICMS  Show/hide abstract 
ARTIN meeting: Wendy Lowen (Antwerp)
1st December 2012, 12:00pm to 1:00pm JCMB, Lecture Theatre C  Show/hide abstract 
ARTIN meeting: Michele D'Adderio (University Libre de Bruxelles)
1st December 2012, 11:00am to 12:00pm JCMB, Lecture Theatre C  Show/hide abstract 
ARTIN meeting: Oleg Chalykh (Leeds)
1st December 2012, 9:30am to 10:30am JCMB, Lecture Theatre C  Show/hide abstract 
ARTIN meeting: Adrien Brochier (Edinburgh)
30th November 2012, 4:30pm to 5:30pm JCMB, Lecture Theatre B  Show/hide abstract 
ARTIN meeting: Stephane Launois (Kent)
30th November 2012, 3:30pm to 4:30pm JCMB, Lecture Theatre B  Show/hide abstract 
Vladimir Bavula (Sheffield)
20th November 2012, 4:30pm to 5:30pm ICMS (15 South College Street)  Show/hide abstract 
Joe Karmazyn (Edinburgh): Quivers with superpotentials and their deformations
20th November 2012, 3:00pm to 4:00pm ICMS, 15 South College St  Show/hide abstract 
MAXIMALS: Tom Leinster (Edinburgh): The eventual image
13th November 2012, 4:10pm to 5:00pm 6206 JCMB  Show/hide abstract 
MAXIMALS:Martina Balagovic (York)
6th November 2012, 4:30pm to 5:30pm ICMS (15 South College Street)  Show/hide abstract 
MAXIMALS:Spela Spenko (Ljubljana)
23rd October 2012, 4:30pm to 5:30pm ICMS (15 South College Street)  Show/hide abstract 
Maximals: Gwyn Bellamy (Glasgow)
9th October 2012, 4:30pm to 5:30pm ICMS (15 South College Street)  Show/hide abstract 
MAXIMALS: Christian Ballot (Caen): The story of a congruence
25th September 2012, 4:00pm to 5:00pm 5215 JCMB  Show/hide abstract 
Maximals: Osamu Iyama (Nagoya)
19th September 2012, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
Maximals: Stephen Harrap (York)
21st May 2012, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Tom Bridgeland
28th March 2012, 4:10pm to 5:10pm JCMB 5215  Show/hide abstract 
Maximals: Osamu Iyama (Nagoya)
20th March 2012, 4:00pm to 5:00pm JCMB 5215  Show/hide abstract 
Maximals: James Mitchell (St Andrews)
13th March 2012, 4:30pm to 5:30pm ICMS  Show/hide abstract 
Maximals: Christian Korff
13th March 2012, 3:00pm to 4:00pm ICMS  Show/hide abstract 
Maximals: Harry Braden (Edinburgh)
6th March 2012, 4:00pm to 5:00pm James Clerk Maxwell Building 5215  Show/hide abstract 
Maximals: Toby Stafford (Manchester)
28th February 2012, 4:30pm to 5:30pm ICMS, Swanston Room  Show/hide abstract 
Maximals: Colva RoneyDougal (St Andrews)
28th February 2012, 3:30pm to 4:30pm ICMS, Swanston Room  Show/hide abstract 
Maximals: Ali Craw (Glasgow)
21st February 2012, 4:00pm to 5:00pm James Clerk Maxwell Building 6311  Show/hide abstract 
Maximals: Sue Sierra (Edinburgh)
14th February 2012, 4:30pm to 5:30pm ICMS  Show/hide abstract 
Maximals: John Mackay (Oxford)
14th February 2012, 3:00pm to 4:00pm ICMS  Show/hide abstract 
Maximals: JeanBaptiste Gramain (Aberdeen)
31st January 2012, 4:30pm to 5:30pm ICMS  Show/hide abstract 
Maximals: Collin Bleak (St Andrews)
31st January 2012, 3:00pm to 4:00pm ICMS  Show/hide abstract 
Maximals: Chris Smyth (Edinburgh)
24th January 2012, 4:00pm to 5:00pm James Clerk Maxwell Building 5215  Show/hide abstract 
Maximals: Chris Spencer (Edinburgh)
17th January 2012, 4:00pm to 5:00pm James Clerk Maxwell Building 5215  Show/hide abstract 
Maximals: Kiriko Kato (Osaka Furitsu)
29th November 2011, 4:00pm to 5:00pm James Clerk Maxwell Building 6311  Show/hide abstract 
Maximals: Alexander Premet (Manchester)
22nd November 2011, 4:00pm to 5:00pm James Clerk Maxwell Building 6311  Show/hide abstract 
JeanEric Pin, ICMS
21st November 2011, 3:00pm to 4:00pm  Show/hide abstract 
Maximals: Guillaume Pouchin (Edinburgh)
15th November 2011, 4:00pm to 5:00pm Room 6311, James Clerk Maxwell Building, Edinburgh.  Show/hide abstract 
Maximals: Maria Chlouveraki (Edinburgh)
1st November 2011, 4:00pm to 5:00pm James Clerk Maxwell Building 6311  Show/hide abstract 
Maximals: Gwyn Bellamy (Manchester)
25th October 2011, 4:00pm to 5:00pm James Clerk Maxwell Building 5326  Show/hide abstract 
Maximals: Tomoyuki Arakawa (RIMS, Kyoto)
18th October 2011, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Michael Collins (Oxford)
18th October 2011, 2:30pm to 3:30pm JCMB 6311  Show/hide abstract 
Maximals: Liam o'Carroll
11th October 2011, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Tom Lenagan
4th October 2011, 4:00pm to 5:00pm JCMB 6311  Show/hide abstract 
Maximals: Alvaro Nolla de Celis
27th September 2011, 4:00pm to 5:00pm JCMB 5326  Show/hide abstract 
Maximals: Hokuto Uehara (Tokyo Met)
23rd August 2011, 4:00pm to 5:00pm 6311 JCMB  Show/hide abstract 
Maximals: Vikraman Balaji
31st May 2011, 4:10pm to 5:10pm JCMB 4312  Show/hide abstract 
Maximals: Alexander Young
13th May 2011, 3:00pm to 4:00pm JCMB 6206  Show/hide abstract 
MAXIMALs: Jan Grabowski (Oxford)
3rd May 2011, 4:10pm to 5:00pm JCMB 4312  Show/hide abstract 
in room S01 Colin Maclaurin Bldg, HW University Lisa Frenkel will speak on `Regular sets and counting in free groups'
16th March 2011, 4:15pm to 5:15pm room S01 Colin Maclaurin Bldg, HW University Lisa Frenkel will speak on `Regular sets and counting in free groups' 
Maximals: Sue Sierra
8th March 2011, 4:10pm to 5:10pm JCMB 6311  Show/hide abstract 
Maximals: Yann Palu (Leeds)
15th February 2011, 4:10pm to 5:10pm JCMB 6311  Show/hide abstract 
Maximals/Geometry: Sinan Unver (Koc)
10th February 2011, 4:10pm to 5:10pm JCMB 5326  Show/hide abstract 
MAXIMALs: Stefan Kolb (Newcastle)
1st February 2011, 4:10pm to 5:10pm 6311 JCMB  Show/hide abstract 
MAXIMALs: Natalia Iyudu (Bonn)
18th January 2011, 4:10pm to 5:10pm JCMB 5327  Show/hide abstract 
MAXIMALs: Vladimir Bavula (Sheffield)
13th January 2011, 4:10pm to 5:10pm JCMB 6311  Show/hide abstract
Talks in past semesters
Apologies, the calendar for Spring 2015 is temporarily down.
Tuesday 20 January 3pm  Robert Laugwitz (Oxford)  Braided Drinfeld and Heisenberg doubles and TQFTs with defects 
A uniform categorical description for both the Drinfeld center and a Heisenberg analogue called the Hopf center of a monoidal category (relative to a braided monoidal category) is presented using morphism categories of bimodules. From this categorical definition, one obtains a categorical action as well as a definition of braided Drinfeld and Heisenberg doubles via braided reconstruction theory. In examples, this categorical picture can be used to obtain a categorical action of modules over quantum enveloping algebras on modules over quantum Weyl algebras. Moreover, certain braided Drinfeld doubles give such an action on modules over rational Cherednik algebras using embeddings of Bazlov and Berenstein of these algebras into certain braided Heisenberg doubles which can be thought of as versions of the Dunkl embeddings. We argue that the corresponding braided Drinfeld doubles can serve an quantum group analogues in the setting of complex reflection groups. Finally, the categorical description can be extended naturally to give TQFTs with defects using recent work of FuchsSchaumannSchweigert.  
Tuesday 13 January 3pm  Richard Hepworth (Aberdeen)  A homology theory for graphs 
Tom Leinster recently introduced an invariant of graphs called the magnitude. In this talk I will define a homology theory for graphs that categorifies the magnitude, in the sense that the magnitude of a graph can be recovered from its homology by taking the Euler characteristic. (Thus this is categorification in the same sense that Khovanov homology categorifies the Jones polynomial.) Important properties of the magnitude can then be seen as shadows of properties of homology. For example, magnitude satisfies an inclusionexclusion formula that can be recovered from a MayerVietoris theorem in homology. The talk will (hopefully) be accessible for anybody who knows what graphs and chain complexes are, and I will try to illustrate it with lots of pictures and examples. 
Talks from Fall 2014:
Tuesday 2 December 3pm  Bin Shu (East China Normal)  Generic property and conjugacies of Borel subalgebras for restricted Lie algebras 
For a finitedimensional restriicted Lie algebra $g$ over an algebraically closed field of prime characteristic, we introduce the notion "generic property", saying that a restricted Lie algebra satisfies such a property if it admits generic tori introduced in BFS. A Borel subalgebra of $g$ is defined as a maximal solvable subalgebra containing a maximal torus of $g$, which is further called generic if additionally containing a generic torus. In this talk, we first verify that a conjecture of Premet on regular Cartan subalgebras for $g$ is valid when $g$ satisfies the generic property, and show that his conjecture does not hold whenever $g$ does not satisfy the generic property. We finally classify the conjugacy classes of Borel subalgebras of the restricted simple Lie algebras $g=W(n)$ under $Aut(g)$conjugation when $p>3$, and present the representatives of these classes. We also describe the closed connected solvable subgroups of $G$ associated with those representative Borel subalgebras.  
Tuesday 25 November 3pm  Martin Kalck (Edinburgh)  Spherical subcategories and new invariants for triangulated categories 
Motivated by examples arising in algebraic geometry, we study objects of klinear triangulated categories with twodimensional graded endomorphism algebra. Given such an object, we show that there is a unique maximal triangulated subcategory, in which the object is spherical, i.e. a CalabiYau object. In many examples, both from representation theory and geometry these spherical subcategories admit explicit descriptions. Furthermore, the collection of all spherical subcategories ordered by inclusion yields a new invariant for triangulated categories. We derive coarser invariants like height, width and cardinality of this poset. This talk is based on joint work with A. Hochenegger & D. Ploog.  
Tuesday 18 November 3pm  David Pauksztello (University of Manchester)  An introduction to cotstructures and costability conditions 
In this talk we introduce the ideas of cotstructures and costability conditions and compare and contrast with tstructures and stability conditions. We show that the space of costability conditions on a triangulated category forms a complex manifold, and give some examples. Part of this talk is joint work with Peter Jorgensen (NewcastleuponTyne).  
Tuesday 18 November 4pm  Rupert Yu (University of Reims)  Jet schemes of nilpotent orbit closures 
In this talk, we investigate jet schemes of nilpotent orbit closures in semisimple Lie algebras. For the regular nilpotent orbit, its closure is the nilpotent cone, and their jet schemes are always irreducible. This was conjectured by Eisenbud and Frenkel, and was proved as a special case of a result of Mustata in a more general setting. We shall see that for a non regular and non zero nilpotent orbit, the jet schemes of its closure are not irreducible in general, and we may obtain from this information on certain geometric properties of nilpotent orbit closures. This is a joint work in progress with Anne Moreau.  
Tuesday 11 November 4pm  Arend Bayer (Edinburgh)  The space of stability conditions on abelian threefolds (and a few CY 3folds) 
I will explain recent joint work with Emanuele Macri and Paolo Stellari, in which we describe the space of Bridgeland stability conditions on threedimensional abelian varieties, and on (crepant resolutions of) their quotients by finite group actions. As I will explain, a lot of the structure is described by some elementary real algebraic geometry (configurations of points with respect to quadratic forms and components of the space of selfmaps of the real projective line). Understanding this geometry allows us to strengthen and generalize the results by Antony Maciocia and Dulip Piyaratne (who were first to construct stability conditions on abelian varieties of Picard rank one with principal polarization).  
Tuesday 4 November 3pm  Karel Casteels (University of Kent)  Combinatorial Models of Quantum Matrix Algebras 
Some socalled "quantum matrix algebras" that are often defined by generators and relations (e.g, quantum matrices, the quantum special linear group, the quantum grassmannian, quantum symmetric and skewsymmetric matrices) can be embedded into a quantum torus by way of a certain directed graph. We are then able to "see" the generators and relations quite naturally, and, perhaps more importantly, we can use these models to study the prime and primitive spectra. Some of the work to be discussed is based on discussions with Stephane Launois and Tom Lenagan.  
Tuesday 28 October 3pm  Christian Lomp (University of Porto)  Semisimple Hopf algebra actions 
We review Hopf algebra actions on rings with particular emphasis on a question raised by Miriam Cohen in 1985 whether the smash product A # H of a semisimple Hopf algebra H acting on a semiprime algebra A is itself a semiprime ring. This question is open until now. In my talk I give a survey on known results concerning Cohen's question.  
Tuesday 28 October 4pm  Paula Carvalho (University of Porto)  On the injective hulls of simple modules over Noetherian Rings 
The Jacobson's conjecture is an open problem in ring theory and asks whether the intersection of the powers of the Jacobson radical of a twosided Noetherian ring is zero. Jategaonkar answered the conjecture in the affirmative for a Noetherian ring R under an additional assumption (called FBN) which in particular implies that any finitely generated essential extension of a simple left Rmodule is Artinian. The latter condition, denoted by $( \diamond )$, is a sufficient condition for a positive answer to the Jacobson's conjecture. In this talk we will consider some Noetherian algebras and study if or when they satisfy $(\diamond)$. In particular, we will be interested in the case of differential operator rings $R\theta; d$ with $R$ a commutative Noetherian ring and $d$ a derivation.  
Tuesday 30 September 3pm  Evgeny Feigin (National Research University, Russia)  PBW filtration and nonsymmetric Macdonald polynomials 
We discuss the recently conjectured connection between the nonsymmetric Macdonald polynomials and the Poincaré–Birkhoff–Witt filtration on Demazure modules of affine KacMoody Lie algebras. The conjecture has a surprising consequence relating PBW degrees of the extremal vectors in finite dimensional representations of simple Lie algebras with the extremal part of Macdonald polynomials. We also describe the connection with the Kostant qpartition function. The talk is based on joint work with I.Cherednik and I.Makedonskyi. 
Talks take place in the James Clerk Maxwell Building, room 6311.
Not part of MAXIMALS but related:
From 1519 December 2014, there will be a workshop on Homological Interactions between Representation Theory and Singularity Theory at the University of Edinburgh.
Talks 20132014:
WARNING: Any error in the notes of the talks is probably due to the notetaker.
Tuesday May 27th 2:30pm  Andre Leroy, (University of Artois)  Euclidean pairs , quasi Euclidean rings and continuant polynomials 
Starting with problem of decomposition of 2 by 2 singular matrices we will introduce Euclidean pairs and quasi Euclidean rings. We will characterise these rings in different ways and show that unitregular rings are quasiEuclidean. We will present relations with constant polynomials and other families of polynomials defined by linear recurrence relations.  
Tuesday May 27th 1:00pm  Maria Chlouveraki (Versailles)  YokonumaHecke and YokonumaTemperleyLieb algebras 
YokonumaHecke algebras were introduced by Yokonuma in the 60's as generalisations of IwahoriHecke algebras. They have recently attracted the interest of topologists, because they naturally give rise to invariants for framed and classical knots. In this talk we will introduce and study the YokonumaHecke algebras of type A and the YokonumaTemperleyLieb algebras, which are the generalisations of classical TemperleyLieb algebras in this case, mainly from the algebraic point of view.  
Friday May 16th 1:00pm JCMB 6206  Noah Snyder (IU Bloomington)  Local Topological Field Theory and Fusion Categories 
Topological field theories give a close relationship between topology and algebra. Traditionally the main application has been from algebra to topology: using algebraic constructions like quantum groups to produce topological invariants. However, you can also run the applications the other way, using topology to arrange and clarify your knowledge about algebra. The goal of this talk is to explain one such application. More specifically, a fusion category is a category that looks like the category of representations of a finite group: it has a tensor product, duals, is semisimple, and has finitely many simple objects. A somewhat mysterious fact about fusion categories (generalizing a theorem of Radford's about Hopf algebras) is that the quadruple dual functor is canonically isomorphic to the identity functor. I will explain this mystery by showing that it follows directly from the Dirac belt trick. The main technique in this proof is the construction of a local topological field theory attached to any fusion category. Topological field theories are invariants of manifolds which can be computed by cutting along codimension 1 boundaries. Local topological field theories allow cutting along lower codimension boundaries. Since manifolds with corners can be glued together in many different ways, this can be formalized using the language of ncategories. Using Lurie's version of the BaezDolan cobordism hypothesis, we describe local field theories with values in the 3category of tensor categories. This is joint work with Chris Douglas and Chris SchommerPries. I will not assume prior familiarity with fusion categories or ncategories.  
Tuesday, May 13th 3:00pm  Carl Mautner (MPIM Bonn)  Modular Representation Theory and Parity Sheaves 
In the 1920's, Weyl proved a formula for the characters of the irreducible representations of reductive groups (e.g., the general linear group) over the complex numbers. In 1979, George Lusztig announced a conjectural character formula for representations of reductive groups over fields of positive characteristic. I will briefly discuss a history of the problem and explain the role of geometric objects called parity sheaves in recent advances.  
Tuesday, April 22nd 3:00pm  Dorette Pronk (Dalhousie)  Weakly globular double categories  a new model for weak 2categories. 
In this talk I will discuss a new model for weak 2categories. We will first show that there is more than one way to make 2categories weak. Bicategories are obtained from 2categories by relaxing the associativity and unit conditions, and requiring that they only hold up to coherent isomorphisms. But they are strict in the sense that we require them to have a set (or, class) X_0 of objects. To introduce the notion of weakly globular double category, we we will relax this requirement: rather, than requiring that we have a discrete set of objects (we call that the globularity condition), we will require that X_0 be a posetal groupoid (i.e., a set with equivalence relation). This is the weak globularity condition. The arrows in X_0 are distinct from the other arrows in the category, so we have now two classes of arrows, and this leads us to the notion of a double category. Weakly globular double categories are strict double categories that satisfy the weak globularity condition and an additional lifting condition on its double cells. I will discuss these conditions in detail and the show that this is sufficient to model weak 2categories in the sense that there is a biequivalence between the 2category of bicategories, homomorphisms and icons, and the 2category of weakly globular doublce categories, pseudo functors and vertical transformations. This biequivalence factors through the 2category of Tamsamani weak 2categories. If there is enough time I will discuss the construction of a weakly globular double category of fractions and its universal properties.  
Tuesday, Apr 8th 3pm  Alexey Sevastyanov (Aberdeen)  A proof of De ConciniKacProcesi conjecture 
In 1992 De Concini, Kac and Procesi observed that isomorphism classes of irredicible representations of a quantum group at odd primitive root of unity m are parameterized by conjugacy classes in the corresponding algebraic group. They also conjectured that the dimensions of irreducible representations corresponding to a given conjugacy class O are divisible by \(m^{1/2 dim O}\). In this talk I shall prove an improved version of this conjecture and derive some important consequences of it related to qW algebras.  
Tuesday, Apr 1st 3pm  Elisa Gorla (Basel)  Universal Groebner bases for ideals of maximal minors 
In 1993, Bernstein, Sturmfels, and Zelevinsky proved that the maximal minors of a matrix of variables form a universal Groebner basis. We present a very short proof of this result, along with a broad generalization to matrices with multi homogeneous structures. Our main tool is a rigidity statement for radical Borel fixed ideals in multigraded polynomial rings. This is joint work with A. Conca ed E. De Negri (University of Genoa).  
Tuesday, Mar 25th 4pm  Claudio Sibilia (ETH Zürich)  Chen homological connection for G spaces. 
Chen homological connections are flat connections on a trivial bundle that can be build on any topological smooth manifold. The goal of the talk is to explain the relation between the Chen homological connection and the KZ equations in genus 0, and extends this formalism to compute some formal connections in genus 1 that are very close to the KZB connection.  
Tuesday, Mar 25th 3pm  Iordan Ganev (Univ. Texas)  Quantizations of multiplicative hypertoric varieties 
Multiplicative hypertoric varieties are symplectic analogues of toric varieties related to symplectic resolutions, hyperplane arrangements, and geometric representation theory. We construct quantizations, depending on a parameter $q$, of multiplicative hypertoric varieties using an algebra of difference operators on affine space. Furthermore, when $q$ is a root of unity, we show that the quantization acquires a large center and defines a matrix bundle (i.e. Azumaya algebra) over the multiplicative hypertoric variety. This is joint work with David Jordan.  
Tuesday, Mar 18th 3pm  Ben Webster (U Virginia/Paris 6)  Hodge seminar 
Tuesday, Mar 4th 3pm  Felipe Rincon (Warwick)  Positroids and the totally nonnegative Grassmannian 
Positroids are combinatorial objects that can be used to index the different strata in certain wellbehaved decompositions of the Grassmannian and its positive part. In this talk I will present joint work with Federico Ardila and Lauren Williams, in which we study some of the combinatorial properties of positroids. As an application, we prove da Silva's 1987 conjecture that any positively oriented matroid is representable over the field of rational numbers. In particular, this implies that the positive matroid Grassmannian (or positive MacPhersonian) is homeomorphic to a closed ball.  
Wendesday, Feb 26th 1:10pm  Adam Chapman (Belgium) Clifford Algebras of Binary Cubic Forms in Characteristic 3  
his talk is based on a joint work with JungMiao Kuo. The structure of Clifford algebras of binary cubic forms in characteristic different from 3 has been described in full detail by Haile. Kuo has generalized his results for the algebra associated to a ternary cubic curve in characteristic different from 3. Here we shall talk about the analogous results in case of characteristic 3.  
Tuesday, Feb 25th 3pm  Johanna Hennig (UCSD)  Locally finite Lie algebras in positive characteristic 
For finite dimensional Lie algebras, there is the wellknown Ado’s theorem: Every finite dimensional Lie algebra embeds into a finite dimensional associative algebra. Bahturin, Baranov, and Zalesski proved an infinite dimensional version of Ado’s theorem for a simple, locally finite Lie algebra L over a field of characteristic zero: L embeds into a locally finite associative algebra if and only if L is isomorphic to the commutator of skewsymmetric elements of a locally finite, associative algebra with involution. We extend this result to fields of positive characteristic—we provide two structure theorems which reduce to Bahturin, Baranov, Zalesski’s result in characteristic zero and also generalize classical structure theorems for finite dimensional Lie algebras in characteristic p.  
Friday, Feb 14th 3pm  Erez Sheiner (Bar Ilan)  Exploded Layered Tropical Algebra 
ELT algebra is an extension of the maxplus algebra, which is a lesser degeneration of algebraic varieties. Using the layered structure we define roots of polynomials and singularity of matrices, despite the lack of an additive inverse. I will not assume familiarity with tropical geometry.  
Tuesday, Feb 11th 3pm  Greg Ginot (Paris 6)  Factorization algebras and applications to centralizers and Bar construction. 
in the first part of the talk, we will discuss the notion of centralizers of Enalgebras maps which shall can be thought as "higher" generalizations of Hochschild cohomology and we will explain how one can see describe them in terms of factorization algebras. Factorization algebras will be detailled in the second part of the talk. They can be thought of as a "nonabelian" version of cosheaves. We will also give an analogue of the Bar constructions for Factorization algebras.  
Tuesday, Feb 4th 3pm  Sian Fryer (Manchester)  The qDivision Ring and its Fixed Rings 
The qdivision ring (denoted here by D) is one of the easiest examples of noncommutative infinite dimensional division rings to define, but answering even fairly basic questions concerning the structure of its automorphism group or its subdivision rings of finite index is still quite difficult. The second question in particular is of interest due to its connections with Artin's conjectured classification of surfaces in noncommutative algebraic geometry. I will describe the structure of the fixed rings of D for a certain class of finite groups and use this to construct some rather unexpected examples of homomorphisms on D, including a conjugation automorphism which is not inner and a conjugation homomorphism which is not even bijective.  
Tuesday, Jan 28th 4pm  Michael Wemyss (Edinburgh)  Noncommutative deformations and applications 
I will mainly talk on my joint work with Will Donovan (1309.0698) which gives new invariants to any contractible curve using noncommutative deformation theory. I will explain a little about our motivation, and why studying noncommutative deformations is strictly necessary. In the setting of 3fold flops, we obtain many new examples of finite dimensional selfinjective algebras, and I will give some of their properties. If I have time, I will say a bit about how this helps to run the minimal model program in dimension three.  
Tuesday, Jan 21st 3pm  JeanMarie Bois (Kiel)  Weyl groups for restricted lie algebras, and the Chevalley restriction theorem 
Tuesday, Jan 7th 3pm  David Gepner (Regensburg)  Brauer groups of commutative ring spectra 
We define and study Azumaya algebras over a commutative (or E_\infty) ring spectrum R, and study the homotopy groups of the resulting Brauer space (of Azumaya Ralgebras up to Morita equivalence). Our main technical tool is an etalelocal triviality result for Azumaya algebras over connective derived schemes (in the sense of J. Lurie, and inspired by a similar result of B. Toen) and a localtoglobal result for the compact generation of Rlinear \inftycategories with descent. The result is a spectral sequence for the homotopy groups of the Brauer space whose E_2 term consists entirely of ordinary etale cohomology groups, and which is often entirely computable. This is joint work with Ben Antieau.  
December 6th, 3pm @ICMS Joint w/ HeriotWatt  Anne Thomas (Glasgow)  Quasiisometry of rightangled Coxeter groups 
A group G with a finite generating set S can be considered as a metric space by endowing it with the word metric with respect to S. Up to quasiisometry, this metric on G does not depend on S. A major theme in geometric group theory is to classify all finitely generated groups up to quasiisometry. We investigate the quasiisometric classification of rightangled Coxeter groups using divergence of geodesics and topological features of their boundaries at infinity. This is joint work with Pallavi Dani.  
December 6th, 4pm @ICMS Joint w/ HeriotWatt  Ghislain Fourier (Glasgow)  Fusion products and symmetric functions 
Fusion products for current algebras have been introduced fifteen years ago. Roughly speaking, they make use of the natural grading of the polynomial ring to form graded tensor products of simple modules for a simple complex Lie algebra. These fusion products play a crucial role in the study of finitedimensional modules for current or loop algebras, for instance they recover Weyl modules and Demazure modules to name but a few. Although intensively studied, various fundamental questions are not answered yet, for example about defining relations or graded character formulas. The current state of art and as well as the strong connection to conjectures about Schur positivity of symmetric functions (and recent results here) will be presented.  
November 26, 3pm  Emily Dufresne (Basel)  Separating invariants and local cohomology 
The study of separating invariants is a new trend in Invariant Theory and a return to its roots: invariants as a classification tool. For a finite group acting linearly on a vector space, a separating set is simply a set of invariants whose elements separate the orbits of the action. Such a set need not generate the ring of invariants. In this talk, we give lower bounds on the size of separating sets based on the geometry of the action. These results are obtained via the study of the local cohomology with support at an arrangement of linear subspaces naturally arising from the action. (joint with Jack Jeffries)  
November 26, 4pm  Ines Henriques (Sheffield)  Fthresholds and Test ideals for determinantal ideals of maximal minors. 
Test ideals first appeared in the theory of tight closure, and reflect the singularities a ring of positive characteristic. Motivated by multiplier ideals in characteristic zero, N. Hara and K. Yoshida defined (generalized) test ideals as their characteristic p analogue. Whereas multiplier ideals are defined geometrically, using log resolutions, test ideals are defined algebraically using the Frobenius morphism. The test ideals of an ideal I form a nonincreasing, right continuous family, {τ(c . I)}, parametrized by a positive real parameter c. The points of discontinuity in this parametrization, are called Fthresholds of I and form a discrete subset of the rational numbers (BlickleMustaţăSmith, Hara, TakagiTakahashi, SchwedeTakagi, KatzmanLyubeznikZhang). We consider ideals generated by maximal minors of a matrix of indeterminates, in its polynomial ring over a field of positive characteristic. Using an algebraic approach, we identify their Fthresholds and test ideals.  
November 19, 3pm  Tom Lenagan (Edinburgh)  Totally nonnegative matrices 
A real matrix is totally nonnegative if each of its minors is nonnegative, and is totally positive if each minor is greater than zero. We will outline connections between the theory of total nonnegativity and the torus invariant prime spectrum of the algebra of quantum matrices, and will discuss some new and old results about total nonnegativity which may be obtained using methods derived from quantum matrix methods. Most of the material is joint work with Stephane Launois and Ken Goodearl. NOTE: much of the material to be presented has been included in earlier seminars in Edinburgh.  
November 13 (Wednesday!), 4pm  David Alan Jordan (Sheffield)  Connected quantized Weyl algebras 
Connected quantized Weyl algebras are algebras with a PBW basis in which any two generators either qcommute or satisfy a quantum Weyl relation xyqyx=1q. The connectedness condition ensures, in some sense, enough quantum Weyl relations. The talk will begin with some discussion of how the motivating examples arose from work of Fordy and Marsh on periodic quiver mutation and Poisson algebras and then proceed to a classification of the connected quantized Weyl algebras and the determination of their prime ideals.  
October 25 (Friday!), 45pm  Chris Dodd (Toronto)  Cycles of Algebraic Dmodules in positive characteristic 
I will explain some ongoing work on understanding algebraic Dmoldules via their reduction to positive characteristic. I will define the pcycle of an algebraic Dmodule, explain the general results of Bitoun and Van Den Bergh; and then discuss a new construction of a class of algebraic Dmodules with prescribed pcycle.  
October 28 (Monday!), 3pm  David Evans (Cardiff)  The search for the exotic  subfactors and conformal field theory 
Subfactor theory provides a framework for studying modular invariant partition functions in conformal field theory, and candidates for exotic modular tensor categories. I will describe work with Terry Gannon on the search for exotic theories beyond those from symmetries based on loop groups, WessZuminoWitten models and finite groups.  
October 23 23pm, 45pm, 24th 45pm, (WTh!)  Chris Dodd (Toronto)  Quantizations of Conic Symplectic Varieties and Representation theory 
I will describe some recent progress joint with G. Bellamy, K. McGerty, and T. Nevins in understanding modules over algebraic quantizations of certain nice classes of symplectic varieties. In particular, I will explain in a leisurely fashion how quantizations come up in representation theory, how one can use the presence of a torus action to study modules over these quantizations, and the types of results (geometric and representationtheoretic) that come from this way of thinking.  
October 22, 3pm  Nick Gurski (Sheffield)  Categorical operads 
Operads are a convenient tool for encoding certain kinds of algebraic structures, and they are in heavy use in algebraic topology and homological algebra. There are some special features of operads in Cat, the (2)category of categories, as well as a number of features shared with operads in other categories. I will review the basics of the general theory, and then talk about a couple of things special to the case of Cat. In the second hour, I plan to focus on how equivariance plays an important role in this story.  
October 15, 3pm  Joe Chuang (City University London)  Algebra with surfaces 
Frobenius algebras give rise to topological invariants of surfaces. I will review this idea (twodimensional topological ﬁeld theory) and describe joint work with Andrey Lazarev on a similar construction.  
October 8, 3pm  Uzi Vishne (Bar Ilan)  pcentral elements and subspaces in central simple algebras 
The major open question on central simple algebras is the cyclicity problem: are all algebras of prime degree cyclic? Any cyclic algebra of degree p has pcentral elements: noncentral elements whose ppower is central. The cyclicity problem can thus be studied using subspaces of pcentral elements, which will be the main topic of the lecture. We will discuss such subspaces from various points of views: chain lemmas, the symbol length problem, connections with elementary number theory, and a new construction in nonassociative algebra.  
October 8, 4pm  Be'eri Greenfeld (Bar Ilan)  Unions over chains of prime ideals 
In a commutative ring, the union over a chain of prime ideals is prime. This is not true in the general case: there exist counterexamples from many classes, including nil rings, locally finite rings, affine algebras with polynomial growth and rings satisfying a polynomial identity (PI). In the latter case, though, the maximal number of nonprime unions of subchains of a chain of prime ideals is (tightly) bounded by the PIclass ,hence finite; this is far from being true in general. In this talk we discuss several examples with additional properties (e.g. primitivity), positive results and suggestions for further research directions. This is based on joint work with Louis Rowen and Uzi Vishne.  
October 1, 3pm  David Andrew Jordan (Edinburgh)  Quantum differential operators and the torus \( T^2 \) 
Abstract: The algebra \( D_q(G) \) is a \(q \)deformation of the algebra \( D(G) \) of differential operators on a semisimple algebraic group. In this talk, I will explain an intimate relationship between \(D_q(G)\) and the torus \(T^2 \): namely, \( D_q(G) \) carries an action by algebra automorphisms of the torus mapping class group \(SL_2(\mathbb{Z}) \), and also yields representations of the torus braid group extending the wellknown action of the planar braid group on tensor powers of quantum group representations. Finally, the socalled Hamiltonian reduction of \( D_q(G) \) quantizes the moduli space \( Loc_G(T^2) \) of \(G\)local systems on \(T^2\), or equivalently, homomorphisms \(\pi_1(T^2)\to G\),and this observation allows us to generalize the construction of \(D_q(G)\) to quantize \(Loc_G(\Sigma_{g,r})\), for an arbitrary surface with genus g and r punctures. Time permitting, I will outline work in progress with David BenZvi and Adrien Brochier putting all of the above into the context of topological field theories.  
October 1, 4pm  Natalia Iyudu (Edinburgh)  A proof of the Kontsevich conjecture on noncommutative birational transformations 
I will talk about our recent proof (arXiv1305.1965) of the Kontsevich conjecture dated back at 1996, and mentioned at the 2011 Arbeitstagung talk on 'Noncommutative identities' (arXiv1109.2469). This conjecture says that certain transformations given by matrices over free noncommutative algebra with inverses ('free field' due to P.Cohn) are periodic, on the level of orbits of the left/right diagonal action. Namely, let \( (M_{ij})_{1 \leq i,j \leq 3} \) be a matrix, whose entries are independent noncommutative variables. Let us consider three 'birational involutions' $$ I_1: \,\, M \to M^{1} $$ $$I_2: \,\, M_{ij} \to (M_{ij})^{1}, \,\, \forall i,j $$ $$I_3: \,\, M \to M^t$$ Then the composition \(\Phi = I_1 \circ I_2 \circ I_3 \) has order three.  
September 24, 3pm  Gwyn Bellamy (Glasgow)  Generalizing Kashiwara's equivalence to conic quantized symplectic manifolds 
Abstract: Kashiwara's equivalence, saying that the category of Dmodules on a variety X support on a smooth, closed subvariety Y is equivalent to the category of Dmodules on Y, is a key result in the theory of Dmodules. In this talk I will explain how one can generalize Kashiwara's result to modules for deformationquantization algebras on a conic symplectic manifold. As an illustrative application, one can use this result to calculate the additive invariance such as the Ktheory and Hochschild homology of these module categories. This is based on joint work C. Dodd, K. McGerty and T. Nevins.  
September 17, 3pm  Stefan Kolb (Newcastle)  Radial part calculations for affine sl2 
Abstract: In their seminal work in the 1970s Olshanetsky and Perelomov used radial part calculations for symmetric spaces to prove integrability of the CalogeroMoser Hamiltonian for special parameters. In this talk, restricting to affine sl2, we will explore what happens if one extends their argument to KacMoody algebras. I will try to explain how this leads to a blend of the KZBheat equation and Inozemtsev's extension of the elliptic CalogeroMoser Hamiltonian.  
September 9 (Monday!), 5pm  Francois Petit (Edinburgh)  FourierMukai transform in the quantized setting 
Abstract: After reviewing some elements of the theory of Deformation Quantization modules (DQmodules), I will show that a coherent DQkernel induces an equivalence between the derived categories of coherent DQmodules if and only if the graded commutative kernel associated to it induces an equivalence between the derived categories of coherent Omodules.  
September 9 (Monday!), 4pm  Hendrik Suess (Edinburgh)  Equivariant vector bundles on TVarieties 
Abstract: By Klyachko's work there is an equivalence of categories between equivariant vector bundles on toric varieties and families of vector space filtrations. In this talk I will discuss an generalization of this equivalence to bundles on varieties with smaller torus actions. Now, vector space filtrations are replaced by filtrations of vector bundles on some quotient space. This description comes with a nice splitting criterion and allows to prove that vector bundles of low rank on projective space, which are equivariant with respect to special subtori of the maximal acting torus must split.  
September 4th (Wednesday!), 3pm  Qendrim Gashi (Pristina)  Mazur's inequality, its converse and generalizations 
Abstract: We will study the classical version of Mazur's inequality, comparing Newton and Hodge polygons, and a converse thereof (due to Kottwitz and Rapoport). We will then discuss grouptheoretic generalizations of these results and implications for affine DeligneLusztig varieties. We will conclude with some results from root theory and toric geometry. 