Focaliser sur:
Tous les jours
23 oct. 2023
24 oct. 2023
25 oct. 2023
26 oct. 2023
27 oct. 2023
Indico style
Indico style - inline minutes
Indico style - numbered
Indico style - numbered + minutes
Indico Weeks View
Retour à l'affichage de la conférence
Choisissez le fuseau horaire
Utiliser le fuseau horaire de l'événement/catégorie
Veuillez spécifier un fuseau horaire
Africa/Abidjan
Africa/Accra
Africa/Addis_Ababa
Africa/Algiers
Africa/Asmara
Africa/Bamako
Africa/Bangui
Africa/Banjul
Africa/Bissau
Africa/Blantyre
Africa/Brazzaville
Africa/Bujumbura
Africa/Cairo
Africa/Casablanca
Africa/Ceuta
Africa/Conakry
Africa/Dakar
Africa/Dar_es_Salaam
Africa/Djibouti
Africa/Douala
Africa/El_Aaiun
Africa/Freetown
Africa/Gaborone
Africa/Harare
Africa/Johannesburg
Africa/Juba
Africa/Kampala
Africa/Khartoum
Africa/Kigali
Africa/Kinshasa
Africa/Lagos
Africa/Libreville
Africa/Lome
Africa/Luanda
Africa/Lubumbashi
Africa/Lusaka
Africa/Malabo
Africa/Maputo
Africa/Maseru
Africa/Mbabane
Africa/Mogadishu
Africa/Monrovia
Africa/Nairobi
Africa/Ndjamena
Africa/Niamey
Africa/Nouakchott
Africa/Ouagadougou
Africa/Porto-Novo
Africa/Sao_Tome
Africa/Tripoli
Africa/Tunis
Africa/Windhoek
America/Adak
America/Anchorage
America/Anguilla
America/Antigua
America/Araguaina
America/Argentina/Buenos_Aires
America/Argentina/Catamarca
America/Argentina/Cordoba
America/Argentina/Jujuy
America/Argentina/La_Rioja
America/Argentina/Mendoza
America/Argentina/Rio_Gallegos
America/Argentina/Salta
America/Argentina/San_Juan
America/Argentina/San_Luis
America/Argentina/Tucuman
America/Argentina/Ushuaia
America/Aruba
America/Asuncion
America/Atikokan
America/Bahia
America/Bahia_Banderas
America/Barbados
America/Belem
America/Belize
America/Blanc-Sablon
America/Boa_Vista
America/Bogota
America/Boise
America/Cambridge_Bay
America/Campo_Grande
America/Cancun
America/Caracas
America/Cayenne
America/Cayman
America/Chicago
America/Chihuahua
America/Ciudad_Juarez
America/Costa_Rica
America/Creston
America/Cuiaba
America/Curacao
America/Danmarkshavn
America/Dawson
America/Dawson_Creek
America/Denver
America/Detroit
America/Dominica
America/Edmonton
America/Eirunepe
America/El_Salvador
America/Fort_Nelson
America/Fortaleza
America/Glace_Bay
America/Goose_Bay
America/Grand_Turk
America/Grenada
America/Guadeloupe
America/Guatemala
America/Guayaquil
America/Guyana
America/Halifax
America/Havana
America/Hermosillo
America/Indiana/Indianapolis
America/Indiana/Knox
America/Indiana/Marengo
America/Indiana/Petersburg
America/Indiana/Tell_City
America/Indiana/Vevay
America/Indiana/Vincennes
America/Indiana/Winamac
America/Inuvik
America/Iqaluit
America/Jamaica
America/Juneau
America/Kentucky/Louisville
America/Kentucky/Monticello
America/Kralendijk
America/La_Paz
America/Lima
America/Los_Angeles
America/Lower_Princes
America/Maceio
America/Managua
America/Manaus
America/Marigot
America/Martinique
America/Matamoros
America/Mazatlan
America/Menominee
America/Merida
America/Metlakatla
America/Mexico_City
America/Miquelon
America/Moncton
America/Monterrey
America/Montevideo
America/Montserrat
America/Nassau
America/New_York
America/Nome
America/Noronha
America/North_Dakota/Beulah
America/North_Dakota/Center
America/North_Dakota/New_Salem
America/Nuuk
America/Ojinaga
America/Panama
America/Paramaribo
America/Phoenix
America/Port-au-Prince
America/Port_of_Spain
America/Porto_Velho
America/Puerto_Rico
America/Punta_Arenas
America/Rankin_Inlet
America/Recife
America/Regina
America/Resolute
America/Rio_Branco
America/Santarem
America/Santiago
America/Santo_Domingo
America/Sao_Paulo
America/Scoresbysund
America/Sitka
America/St_Barthelemy
America/St_Johns
America/St_Kitts
America/St_Lucia
America/St_Thomas
America/St_Vincent
America/Swift_Current
America/Tegucigalpa
America/Thule
America/Tijuana
America/Toronto
America/Tortola
America/Vancouver
America/Whitehorse
America/Winnipeg
America/Yakutat
Antarctica/Casey
Antarctica/Davis
Antarctica/DumontDUrville
Antarctica/Macquarie
Antarctica/Mawson
Antarctica/McMurdo
Antarctica/Palmer
Antarctica/Rothera
Antarctica/Syowa
Antarctica/Troll
Antarctica/Vostok
Arctic/Longyearbyen
Asia/Aden
Asia/Almaty
Asia/Amman
Asia/Anadyr
Asia/Aqtau
Asia/Aqtobe
Asia/Ashgabat
Asia/Atyrau
Asia/Baghdad
Asia/Bahrain
Asia/Baku
Asia/Bangkok
Asia/Barnaul
Asia/Beirut
Asia/Bishkek
Asia/Brunei
Asia/Chita
Asia/Choibalsan
Asia/Colombo
Asia/Damascus
Asia/Dhaka
Asia/Dili
Asia/Dubai
Asia/Dushanbe
Asia/Famagusta
Asia/Gaza
Asia/Hebron
Asia/Ho_Chi_Minh
Asia/Hong_Kong
Asia/Hovd
Asia/Irkutsk
Asia/Jakarta
Asia/Jayapura
Asia/Jerusalem
Asia/Kabul
Asia/Kamchatka
Asia/Karachi
Asia/Kathmandu
Asia/Khandyga
Asia/Kolkata
Asia/Krasnoyarsk
Asia/Kuala_Lumpur
Asia/Kuching
Asia/Kuwait
Asia/Macau
Asia/Magadan
Asia/Makassar
Asia/Manila
Asia/Muscat
Asia/Nicosia
Asia/Novokuznetsk
Asia/Novosibirsk
Asia/Omsk
Asia/Oral
Asia/Phnom_Penh
Asia/Pontianak
Asia/Pyongyang
Asia/Qatar
Asia/Qostanay
Asia/Qyzylorda
Asia/Riyadh
Asia/Sakhalin
Asia/Samarkand
Asia/Seoul
Asia/Shanghai
Asia/Singapore
Asia/Srednekolymsk
Asia/Taipei
Asia/Tashkent
Asia/Tbilisi
Asia/Tehran
Asia/Thimphu
Asia/Tokyo
Asia/Tomsk
Asia/Ulaanbaatar
Asia/Urumqi
Asia/Ust-Nera
Asia/Vientiane
Asia/Vladivostok
Asia/Yakutsk
Asia/Yangon
Asia/Yekaterinburg
Asia/Yerevan
Atlantic/Azores
Atlantic/Bermuda
Atlantic/Canary
Atlantic/Cape_Verde
Atlantic/Faroe
Atlantic/Madeira
Atlantic/Reykjavik
Atlantic/South_Georgia
Atlantic/St_Helena
Atlantic/Stanley
Australia/Adelaide
Australia/Brisbane
Australia/Broken_Hill
Australia/Darwin
Australia/Eucla
Australia/Hobart
Australia/Lindeman
Australia/Lord_Howe
Australia/Melbourne
Australia/Perth
Australia/Sydney
Canada/Atlantic
Canada/Central
Canada/Eastern
Canada/Mountain
Canada/Newfoundland
Canada/Pacific
Europe/Amsterdam
Europe/Andorra
Europe/Astrakhan
Europe/Athens
Europe/Belgrade
Europe/Berlin
Europe/Bratislava
Europe/Brussels
Europe/Bucharest
Europe/Budapest
Europe/Busingen
Europe/Chisinau
Europe/Copenhagen
Europe/Dublin
Europe/Gibraltar
Europe/Guernsey
Europe/Helsinki
Europe/Isle_of_Man
Europe/Istanbul
Europe/Jersey
Europe/Kaliningrad
Europe/Kirov
Europe/Kyiv
Europe/Lisbon
Europe/Ljubljana
Europe/London
Europe/Luxembourg
Europe/Madrid
Europe/Malta
Europe/Mariehamn
Europe/Minsk
Europe/Monaco
Europe/Moscow
Europe/Oslo
Europe/Paris
Europe/Podgorica
Europe/Prague
Europe/Riga
Europe/Rome
Europe/Samara
Europe/San_Marino
Europe/Sarajevo
Europe/Saratov
Europe/Simferopol
Europe/Skopje
Europe/Sofia
Europe/Stockholm
Europe/Tallinn
Europe/Tirane
Europe/Ulyanovsk
Europe/Vaduz
Europe/Vatican
Europe/Vienna
Europe/Vilnius
Europe/Volgograd
Europe/Warsaw
Europe/Zagreb
Europe/Zurich
GMT
Indian/Antananarivo
Indian/Chagos
Indian/Christmas
Indian/Cocos
Indian/Comoro
Indian/Kerguelen
Indian/Mahe
Indian/Maldives
Indian/Mauritius
Indian/Mayotte
Indian/Reunion
Pacific/Apia
Pacific/Auckland
Pacific/Bougainville
Pacific/Chatham
Pacific/Chuuk
Pacific/Easter
Pacific/Efate
Pacific/Fakaofo
Pacific/Fiji
Pacific/Funafuti
Pacific/Galapagos
Pacific/Gambier
Pacific/Guadalcanal
Pacific/Guam
Pacific/Honolulu
Pacific/Kanton
Pacific/Kiritimati
Pacific/Kosrae
Pacific/Kwajalein
Pacific/Majuro
Pacific/Marquesas
Pacific/Midway
Pacific/Nauru
Pacific/Niue
Pacific/Norfolk
Pacific/Noumea
Pacific/Pago_Pago
Pacific/Palau
Pacific/Pitcairn
Pacific/Pohnpei
Pacific/Port_Moresby
Pacific/Rarotonga
Pacific/Saipan
Pacific/Tahiti
Pacific/Tarawa
Pacific/Tongatapu
Pacific/Wake
Pacific/Wallis
US/Alaska
US/Arizona
US/Central
US/Eastern
US/Hawaii
US/Mountain
US/Pacific
UTC
Sauver
Europe/Paris
Français
Deutsch (Deutschland)
English (United Kingdom)
English (United States)
Español (España)
Français (France)
Italiano (Italia)
Polski (Polska)
Português (Brasil)
Türkçe (Türkiye)
Čeština (Česko)
Монгол (Монгол)
Українська (Україна)
中文 (中国)
S'authentifier
Geometric and categorical representation theory
de
lundi 23 octobre 2023 (08:00)
à
vendredi 27 octobre 2023 (18:00)
lundi 23 octobre 2023
09:00
The loop space and representations - 1
-
Roman Bezrukavnikov
The loop space and representations - 1
Roman Bezrukavnikov
09:00 - 10:20
I will talk about (relatively) recent ways to apply the affine Grassmannian as an algebro-geometric or topological object to representation theory of the reductive group in positive characteristic or quantum group at a root of unity. Based on works (mostly in progress) with Boixeda Alvarez, McBreen, Yun, Shan, Vasserot and Arinkin.
10:30
Coffee Break
Coffee Break
10:30 - 10:55
11:00
Representations of p-adic groups - 1
-
Jessica Fintzen
Representations of p-adic groups - 1
Jessica Fintzen
11:00 - 12:20
The mini course will provide an introduction to the representation theory of p-adic groups via type theory. The course will include: - basic definitions surrounding representations of p-adic groups - an introduction to Bruhat-Tits theory and Moy-Prasad filtrations - construction of supercuspidal representations: depth-zero representations, (a glimpse of) Yu's construction - Bernstein decomposition - types and non-supercuspidal Bernstein blocks - equivalences between Bernstein blocks, reduction to depth-zero
15:30
Coffee Break
Coffee Break
15:30 - 15:55
16:00
Braid group action on the cohomology of Deligne-Lusztig varieties
-
Cédric Bonnafé
Braid group action on the cohomology of Deligne-Lusztig varieties
Cédric Bonnafé
16:00 - 17:20
If B is the braid group associated with the Weyl group W of a split reductive group G over F_q, and if b is in B, we construct a categorical action of the centralizer C_B(b) on the cohomology of the Deligne-Lusztig variety X(b) associated with b. If b=1, we retrieve the classical algebraic action of the Hecke algebra on the permutation representation of the finite flag variety. As another particular case, we retrieve a geometric action defined by Broué-Michel in 1996. In this talk, we explain the construction of this action, some of its properties (action of the Frobenius, compatibility with Deligne-Lusztig parabolic induction, ...) and we investigate natural questions (for instance, does the image of C_B(b) generate the endomorphism algebra?).
17:30
The integral motivic Satake equivalence
-
Robert Cass
The integral motivic Satake equivalence
Robert Cass
17:30 - 18:50
The geometric Satake equivalence describes the representation theory of the Langlands dual of a split reductive group in terms of sheaves on the affine Grassmannian. Numerous versions of this equivalence are known for different base schemes and cohomology theories, each having their own applications in geometric representation theory. In this talk we discuss a Satake equivalence for integral motivic sheaves which unifies previous versions and refines the rational motivic equivalence of Richarz and Scholbach. This is joint work with Scholbach and van den Hove.
mardi 24 octobre 2023
09:00
Dg trace and center of Hecke categories - 1
-
Matt Hogancamp
Dg trace and center of Hecke categories - 1
Matt Hogancamp
09:00 - 10:20
In this minicourse we will consider the categorification of some quintessential constructions in linear algebra and representation theory, particularly the notion of (co)center of an algebra, and applications to Hecke categories. Talk 1 will introduce a dg version of the usual Drinfeld center and "horizontal trace" of a monoidal category. Talk 2 will discuss dg analogues of highest weight structures, and their application to the dg traces of Hecke categories. Talk 3 will introduce the Curved (or y-ified) Hecke category, its dg trace, and the connection to the Hilbert scheme of points in C^2. These talk are based on joint work (some of it still in progress) with Elias, Gorsky, Makisumi, and Mellit.
10:30
Coffee Break
Coffee Break
10:30 - 10:55
11:00
The loop space and representations - 2
-
Roman Bezrukavnikov
The loop space and representations - 2
Roman Bezrukavnikov
11:00 - 12:20
I will talk about (relatively) recent ways to apply the affine Grassmannian as an algebro-geometric or topological object to representation theory of the reductive group in positive characteristic or quantum group at a root of unity. Based on works (mostly in progress) with Boixeda Alvarez, McBreen, Yun, Shan, Vasserot and Arinkin.
mercredi 25 octobre 2023
09:00
Representations of p-adic groups - 2
-
Jessica Fintzen
Representations of p-adic groups - 2
Jessica Fintzen
09:00 - 10:20
The mini course will provide an introduction to the representation theory of p-adic groups via type theory. The course will include: - basic definitions surrounding representations of p-adic groups - an introduction to Bruhat-Tits theory and Moy-Prasad filtrations - construction of supercuspidal representations: depth-zero representations, (a glimpse of) Yu's construction - Bernstein decomposition - types and non-supercuspidal Bernstein blocks - equivalences between Bernstein blocks, reduction to depth-zero
10:30
Coffee Break
Coffee Break
10:30 - 10:55
11:00
Dg trace and center of Hecke categories - 2
-
Matt Hogancamp
Dg trace and center of Hecke categories - 2
Matt Hogancamp
11:00 - 12:20
In this minicourse we will consider the categorification of some quintessential constructions in linear algebra and representation theory, particularly the notion of (co)center of an algebra, and applications to Hecke categories. Talk 1 will introduce a dg version of the usual Drinfeld center and "horizontal trace" of a monoidal category. Talk 2 will discuss dg analogues of highest weight structures, and their application to the dg traces of Hecke categories. Talk 3 will introduce the Curved (or y-ified) Hecke category, its dg trace, and the connection to the Hilbert scheme of points in C^2. These talk are based on joint work (some of it still in progress) with Elias, Gorsky, Makisumi, and Mellit.
15:30
Coffee Break
Coffee Break
15:30 - 15:55
16:00
A Fourier transform for unipotent representations of p-adic groups
-
Beth Romano
A Fourier transform for unipotent representations of p-adic groups
Beth Romano
16:00 - 17:20
In the representation theory of finite reductive groups, an essential role is played by Lusztig's nonabelian Fourier transform, an involution on the space of unipotent characters of the group. For reductive p-adic groups, the unipotent local Langlands correspondence gives a natural parametrization of irreducible smooth representations with unipotent cuspidal support. However, many questions about the characters of these representations are still open. In joint work with Anne-Marie Aubert and Dan Ciubotaru, we propose a potential lift of Lusztig's Fourier transform to the setting of split p-adic groups and their pure inner twists. Our work generalizes a construction of Moeglin--Waldspurger for orthogonal groups. In my talk, I will introduce some of these ideas via examples.
17:30
Some finiteness properties of Hecke rings of p-adic groups
-
Jean-François Dat
Some finiteness properties of Hecke rings of p-adic groups
Jean-François Dat
17:30 - 18:50
If K is a compact open subgroup of a p-adic group G, the fact that any double K-coset in G is the union of finitely many left K-cosets allows one to define the Hecke ring Z[K\G/K] of the pair (G,K). When K is a hyperspecial subgroup, the C-algebra C[K\G/K] is a f.g. commutative algebra that was described by Satake, and this was the starting point of the Langlands program for automorphic representations. The fact that this description can be made over Z is in turn fundamental for arithmetic applications such as in the Taylor-Wiles method. For general K, C[K\G/K] is no longer commutative, but a famous theorem of Bernsein says that it is finite as a module over its center, which is a f.g. C-algebra. It is conjectured that such a statement should hold over Z. In the talk I will explain why it holds over Z[1/p], and how it somehow unexpectedly follows from the recent work of Fargues and Scholze on the geometrization of the local Langlands correspondence. This is joint work with Helm, Kurinczuk and Moss.
jeudi 26 octobre 2023
09:00
The loop space and representations - 3
-
Roman Bezrukavnikov
The loop space and representations - 3
Roman Bezrukavnikov
09:00 - 10:20
I will talk about (relatively) recent ways to apply the affine Grassmannian as an algebro-geometric or topological object to representation theory of the reductive group in positive characteristic or quantum group at a root of unity. Based on works (mostly in progress) with Boixeda Alvarez, McBreen, Yun, Shan, Vasserot and Arinkin.
10:30
Coffee Break
Coffee Break
10:30 - 10:55
11:00
Representations of p-adic groups - 3
-
Jessica Fintzen
Representations of p-adic groups - 3
Jessica Fintzen
11:00 - 12:20
The mini course will provide an introduction to the representation theory of p-adic groups via type theory. The course will include: - basic definitions surrounding representations of p-adic groups - an introduction to Bruhat-Tits theory and Moy-Prasad filtrations - construction of supercuspidal representations: depth-zero representations, (a glimpse of) Yu's construction - Bernstein decomposition - types and non-supercuspidal Bernstein blocks - equivalences between Bernstein blocks, reduction to depth-zero
15:30
Coffee Break
Coffee Break
15:30 - 15:55
16:00
Arkhipov-Bezrukavnikov for p-adic groups
-
João Lourenço
Arkhipov-Bezrukavnikov for p-adic groups
João Lourenço
16:00 - 17:20
We are going to explain joint work with Johannes Anschütz, Zhiyou Wu, and Jize Yu concerning the Arkhipov--Bezrukavnikov equivalence in mixed characteristic. Kazhdan--Lusztig constructed an isomorphism between the Grothendieck group of equivariant coherent sheaves on the dual Springer variety, and that of equivariant perverse sheaves on the Iwahori flag variety in the function field case. Arkhipov--Bezrukavnikov later lifted this to an isomorphism of the corresponding bounded derived categories, building on Gaitsgory's construction of central sheaves via nearby cycles. Recently, it became possible to carry out the same program for p-adic groups, due to the construction of Witt flag varieties due to Zhu and Bhatt--Scholze, and of the B_dR^+-affine Grassmannian due to Scholze--Weinstein. Relying on previous work with Anschütz, Gleason, and Richarz on p-adic local models, we are able to define a p-adic avatar of Gaitsgory's central functor and also of the Arkhipov-Bezrukavnikov functor. Some of our proofs are new out of necessity due to the constraints of our setup and we will try to highlight the differences. We will also discuss some perfectoid geometry along the way.
17:30
Quantum category O vs affine Hecke category
-
Ivan Loseu
Quantum category O vs affine Hecke category
Ivan Loseu
17:30 - 18:50
I will establish an equivalence between a block of the quantum category O at an odd root of unity and the heart of the "new" t-structure on a suitably singular affine Hecke category
vendredi 27 octobre 2023
08:50
Dg trace and center of Hecke categories - 3
-
Matt Hogancamp
Dg trace and center of Hecke categories - 3
Matt Hogancamp
08:50 - 10:10
In this minicourse we will consider the categorification of some quintessential constructions in linear algebra and representation theory, particularly the notion of (co)center of an algebra, and applications to Hecke categories. Talk 1 will introduce a dg version of the usual Drinfeld center and "horizontal trace" of a monoidal category. Talk 2 will discuss dg analogues of highest weight structures, and their application to the dg traces of Hecke categories. Talk 3 will introduce the Curved (or y-ified) Hecke category, its dg trace, and the connection to the Hilbert scheme of points in C^2. These talk are based on joint work (some of it still in progress) with Elias, Gorsky, Makisumi, and Mellit.
10:20
The anti-spherical Hecke category for Hermitian symmetric pairs
-
Maud De Visscher
The anti-spherical Hecke category for Hermitian symmetric pairs
Maud De Visscher
10:20 - 11:40
In this talk, I will discuss the representation theory of the anti-spherical Hecke categories for Hermitian symmetric pairs (W,P) over a field k of characteristic p. Minimal coset representatives for Hermitian symmetric pairs are fully commutative elements (as defined by Stembridge) and we will see how this property implies a much simplified diagrammatic presentation for the corresponding Hecke categories. I will explain how the representation theory can be reduced to the simply laced cases via explicit graded Morita equivalences. In the simply laced cases, the light leaves basis elements for the Hecke categories can be described in terms of certain generalisations of oriented Temperley-Lieb algebras. It follows from this description that the graded decomposition numbers, that is the p-Kazhdan-Lusztig polynomials for Hermitian symmetric pairs, are all characteristic free. This is based on joint works with C. Bowman, N. Farrell, A. Hazi and E. Norton.