Workshop on Homotopy Theory

July 7 - 11, 2025, The Fields Institute

Location: Fields Institute, Room 230

Description

This workshop will accelerate development of new directions in chromatic and unstable homotopy theory and in the homotopy theory of polyhedral products. Key will be the exploration of areas of interaction: unstable homotopy theory and polyhedral products have substantial existing intersection while recent developments in chromatic homotopy theory suggest exciting new intersections with unstable homotopy theory and polyhedral products.

Schedule

Monday, July 7th, 2025
09:15 to 09:20	Program Welcome Deirdre Haskell, McMaster University and The Fields Institute
09:20 to 09:30	No Title Specified Paul Selick, University of Toronto
09:30 to 10:20	"Just foolin' around," or, The unifying power of graded rings Haynes Miller, Massachusetts Institute of Technology
10:20 to 10:40	Coffee Break
10:40 to 11:30	Equivariant homological stability Eva Belmont, Case Western Reserve University
11:40 to 12:30	Planar loops and the homology of Temperley-Lieb algebras Guy Boyde, Universiteit Utrecht
12:30 to 14:30	Lunch
14:35 to 14:40	Brayton Gray (Afternoon Chair)
14:40 to 15:30	Enriched model categories and the Dold-Kan correspondence Martin Frankland, University of Regina
15:30 to 16:00	Coffee Break
16:00 to 16:30	Quasi-flag manifolds and moment graphs Yun Liu, Indiana University Bloomington
16:30 to 17:00	Loop spaces of polyhedral products associated with polyhedral join products. Briony Eldridge, University of Southampton

Tuesday, July 8th, 2025
09:25 to 09:30	Santiago Lopez de Medrano (Morning Chair)
09:30 to 10:20	Loops, Braids, Rats, and the Kervaire invariant (A tribute to Fred) Ralph Cohen, Stanford University
10:20 to 10:40	Coffee Break
10:40 to 11:30	Isovariant homotopy theory Inbar Klang, Vrije Universiteit Amsterdam
11:40 to 12:30	A turn in Fred’s work Anthony Bahri, Rider University, Martin Bendersky, Hunter College of CUNY
12:30 to 14:30	Lunch
14:25 to 14:30	John McCleary (Afternoon Chair)
14:30 to 14:40	Remembering Fred Helen and Sarah Whalen-Cohen
14:40 to 15:30	Emphasizing structure in the study of 3D incompressible fluid motion Dennis Sullivan, Stony Brook University
15:30 to 16:00	Coffee Break
16:00 to 16:30	Steenrod operations for 4-dimensional toric orbifolds Larry So, (Pusan)
16:30 to 17:00	Chromatic fixed point theory: what we know and what we don't. Nicholas Kuhn, University of Virginia
18:30	Buffet dinner in honour of Fred Cohen

Wednesday, July 9th, 2025
09:25 to 09:30	John Harper (Morning Chair)
09:30 to 10:20	Unstable homotopy by machine Dan Isaksen, Wayne State University
10:20 to 10:40	Coffee Break
10:40 to 11:30	Smooth manifolds in $G_{n,2}$ and $G_{n,2}/T^n$ defined by the canonical $T^n$-action Svjetlana Terzic, University of Montenegro
11:40 to 12:30	Scissors congruence K-theory of manifolds and cobordism categories Mona Merling, University of Pennsylvania
12:30 to 14:30	Lunch

Thursday, July 10th, 2025
09:25 to 09:30	Andy Baker (Afternoon Chair)
09:30 to 10:20	On Swindling a Swindler Inna Zakharevich, Cornell University
10:20 to 10:40	Coffee Break
10:40 to 11:30	An overview of unstable homotopy decompositions Ruizhi Huang, Chinese Academy of Sciences
11:40 to 12:30	The Szczarba map and the cubical cobar construction Matthias Franz, Western University
12:30 to 14:30	Lunch
14:25 to 14:30	Nick Kuhn (Morning Chair)
14:30 to 14:40	Remembering Fred Andy Baker (University of Glasgow)
14:40 to 15:30	Using universes to describe Eilenberg-Mac Lane spaces, Euler classes and cup products Dan Christensen, Western University
15:30 to 16:00	Coffee Break
16:00 to 16:30	Bridging between überhomology and double homology Luigi Caputi, University of Bologna
16:30 to 17:00	Anick's conjecture for polyhedral products Lewis Stanton, University of Southampton

Friday, July 11th, 2025
09:25 to 09:30	Don Stanley (Morning Chair)
09:30 to 10:20	On the Rosenfeld projective planes John Jones, Warwick Mathematics Institute
10:20 to 10:40	Coffee Break
10:40 to 11:30	A motivic approach to efficient generation of projective modules Morgan Opie, University of California, Los Angeles
11:40 to 12:30	A Duoidal Approach to Homological Algebra Dai Tamaki, Shinshu University
12:30 to 14:30	Lunch
14:25 to 14:30	Tony Bahri (Afternoon Chair)
14:30 to 14:40	Remembering Fred Kee Yuen Lam, University of British Columbia
14:40 to 15:30	Topology and Combinatorics Uncovering Structures of Vietoris-Rips Complexes Jelena Grbić, University of Southampton
15:30 to 16:00	Coffee Break
16:00 to 16:50	Permutohedral complex and the complements of diagonal subspace arrangements Taras Panov, Moscow State University

Registered Participants

Name	Affiliation
Anshid Aboobacker	Birla Institute of Technology and Science
Abderrahim Adrabi
Leonard Afeke	University of Toronto
Marcelo Aguilar	UNIVERSIDAD NACIONAL AUTONOMA DE MEXICO
Tala Alaa Eddine	Beirut Arab University
Mariam Al-Hawaj	Trinity College Dublin
David Allen	City University of New York
Omar Alvarado	Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV)
Steven Amelotte	Carleton University
Sarah Anderson	Purdue University
Samia Ashraf	GCWUS Pakistan
Danyal Azaz	University of Toronto
Hadi Azizi	University of Toronto
Anthony Bahri	Rider University
Andrew Baker	University of Glasgow
Luis Alejandro Barbosa Torres	Pontificia Universidad Javeriana
Samik Basu	Indian Statistical Institute, Kolkata
Eva Belmont	Case Western Reserve University
Martin Bendersky	Hunter College of CUNY
Sandipan Bhattacherjee	BIRLA INSTITUTE OF TECHNOLOGY MESRA, RANCHI
Terrence Bisson	Canisius College
Michael Borinsky	Perimeter Institute
Guy Boyde	Universiteit Utrecht
Dylan Burke	University of Toronto
Gianmarco Caldini	University of Trento
Eddy Campbell	Queen's University
Luigi Caputi	University of Bologna
Tobin Carlton Van Buizen	Australia National University
Sean Carroll	Northeastern University
Juan Felipe Celis Rojas	Mathematical Institute - University of Oxford
Himanshu Chaudhary	Albert-Ludwigs-Universitaet Freiburg
Sergio Chaves	Cornell University
Herng Yi Cheng	University of Toronto
Georgii Chernykh	NRU Higher School of Economics
Dan Christensen	Western University
Ralph Cohen	Stanford University
Don Davis	Lehigh University
Soumya Dey	Krea University
Amartya Dubey	NATIONAL INSTITUTE OF SCIENCE EDUCATION AND RESEARCH (NISER),BHUBANESWAR
Briony Eldridge	University of Southampton
Salvatore Elia	University of Southampton
Helen Epelbaum	University of Toronto
Ruslan Erdnigor	University of Toronto
Michael Farber	Queen Mary University of London
Rui Feng	York University
Seher Fişekci	Ankara Science University
Chi-Kwong Fok	Xi'an Jiaotong-Liverpool University
Martin Frankland	University of Regina
Matthias Franz	Western University
William Gao	University of Toronto
Brice Gardner	Australian National University
Dominik Gdesz	University of Wroclaw
Surojit Ghosh	Indian Institute of Technology Roorkee
Sacha Goldman	University of Toronto
Tao Gong	Western University
jesus gonzalez	Cinvestav
Vladimir Gorchakov	Western University
Shashen Gounden	University of Regina
Shuchita Goyal	Birla Institute of Technology and Science
Brayton Gray	University of Illinois at Chicago
Jelena Grbić	University of Southampton
Ian Hambleton	McMaster University
John Harper	University of Rochester
Kamyar Hazaveh	University of Toronto
Joseph Hlavinka	University of California Berkeley
Satyanath Howladar	University of Florida
Ruizhi Huang	Chinese Academy of Sciences
Hana Huber	CUNY Graduate Center
Jiahao Hu	Yau Mathematical Science Center, Tsinghua University
Yang Hu	New Mexico State University
Dan Isaksen	Wayne State University
Elena Isasi Theus	University of Chicago
Leo Jiang	University of Toronto
Yoyo Jiang	Johns Hopkins University
John Jones	Warwick Mathematics Institute
Sadok Kallel	American Univeristy of Sharjah
Krishnendu Kar	Louisiana State University
Andrzej Karolak	University of Wrocław
Jaspreet Kaur	Maharaja Ranjit Singh Punjab Technical University, India
Abdul Khan
Inbar Klang	Vrije Universiteit Amsterdam
Robin Koytcheff	University of Louisiana at Lafayette
Manuel Krannich	Karlsruhe Institute of Technology
Nursultan Kuanyshov	SDU University
Nicholas Kuhn	University of Virginia
Indrajeet Kumar	Indian Institute of Science Education and Research, Thiruvananthapuram
Alex LaJeunesse	University of Colorado Boulder
José J. La Luz	Universidad de Puerto Rico
Kee Yuen Lam	University of British Columbia
Ha Le Minh	Vietnam National University, Hanoi
Porfirio Leandro León Álvarez	Instituto de Matematicas UNAM
José Luis León Medina	Centro de Investigación en Matemáticas.(CIMAT)
Shane Liu	Toronto Metropolitan University
Yun Liu	Indiana University Bloomington
Wenwen Li	St. Mary's College of Maryland
Ying Li	University of Wisconsin–Madison
Yingxin Li	Beijing Normal University
Santiago López de Medrano	Instituto de Matematicas UNAM
Cynthia Ma
Mukhammadrizo Madjidov	University of Toronto
Josue Maldonado	Universidad de Guadalajara
sahin mandal	IIT Bombay
Fedor Manin	University of Toronto
Zhouhang Mao	Universiteit van Amsterdam
Clover May	NTNU Norwegian University of Science and Technology
John McCleary	Vassar College
Amaranta Membrillo Solis	Queen Mary University of London
Mona Merling	University of Pennsylvania
Aleksandar Milivojevic	University of Waterloo
Haynes Miller	Massachusetts Institute of Technology
Qicheng Mi	University of Toronto
EL MOKHTAR MOKKEDEM	Sorbonne University
Marwa Mosallam
Ramana Murugesan	University of Toronto
Taeuk Nam
Barry Ngo	University of Ottawa
Urban Ogrinec	Faculty of Mathematics and Physics, University of Ljubljana
Stephanie Oh	University of Colorado Boulder
Morgan Opie	University of California, Los Angeles
Nadir Ouagnar	University of Bonn
Tamis Panagiotakis	University of Toronto
Lirui Pang	University of Toronto
Taras Panov	Moscow State University
Gargi Patil	Louisiana State University
Elia Portnoy	Massachusetts Institute of Technology
Bo Rao	University Paris 13
Safarul Rasheed	INDIAN INSTITUTE OF SCIENCE EDUCATION AND RESEARCH KOLKATA
Jay Reiter	University of Washington
Samuel Restoy	University of Oklahoma
Jorge Robinson Arrieta	University of Arkansas
Alice Rolf	University of Toronto
Pratik Roy	Northeastern University
Vasilii Rozhdestvenskii	Steklov Mathematical Institute of Russian Academy of Sciences
Hajime Saeki	University of Toronto
Alejandro Saiz Millán	Universidad de Málaga (UMA)
Deepanshi Saraf	Indian Institute of Science Education and Research
Hisham Sati	New York University
Matthew Scalamandre	University of Toronto
Paul Selick	University of Toronto
Alisa Senses	University of St Andrews
Kumar Sannidhya Shukla	Western University
Gunjeet Singh	Wayne State University
Kamil Śmietaniak	Adam Mickiewicz university in Poznan
Tse Leung So	University of Southampton
Mentor Stafa	The Hershey Company
Don Stanley	University of Regina
Lewis Stanton	University of Southampton
Kimball Strong	Cornell University
Dennis Sullivan	Stony Brook University
Yuxuan Sun	University of Toronto
Tan Su	New York University
Dai Tamaki	Shinshu University
Jacob Taylor	University of Toronto
Svjetlana Terzic	University of Montenegro
Stephen Theriault	University of Southampton
Daniel Tolosa	Arizona State University
Vahid Soleimany	vahid soleimani
Ivan Vasilev	Saint-Petersburg State University
Pravin Kumar Vellaisamy	IISER Mohali
Fedor Vylegzhanin	NRU Higher School of Economics
Elon Wang	University of Toronto
YUYANG WANG	University of Toronto
Alex Waugh	University of Washington
Jerry Wei	University of California Berkeley
David White	Denison University
W Stephen Wilson	Johns Hopkins University
Tsz Hin Wong	University of Toronto
Enxin Wu	Shantou University
Miguel Xicotencatl	Centro de Investigacion y de Estudios Avanzados del IPN
Shuhang Xue	University of Minnesota - Twin Cities
Xiaomeng Xu	Beijing Institute of Mathematical Sciences and Applications
Ergun Yalcin	Bilkent University
So Yamagata	Fukuoka University
Juxin Yang	Beijing Institute of Mathematical Sciences and Applications
Shiyu Yan	Leiden University
Sin Hang Jason Yeung	University of Toronto
Ze Yuan	National University of Singapore
Inna Zakharevich	Cornell University
Indira Zeinikesheva	University of Pittsburgh
Mingyang Zhou	Tufts University

Organizing Committee

Anthony Bahri - Rider University

Ruth Charney - Brandeis University

Ran Levi - University of Aberdeen

Paul Selick - University of Toronto

Stephen Theriault - University of Southampton

Jie Wu - Beijing Institute of Mathematical Sciences and Applications

Scheduled as part of

Focus Program on Algebraic Topology In memory of Fred Cohen

The Fields Institute for
Research in Mathematical Sciences