The Midwest Topology Seminar in Winter/Spring 2021 will be held in an online format. Three 45-minute talks will be separated by two 30-minute coffee breaks. The breaks will be structured to provide an opportunity for small group conversation in breakout rooms. Participants will be able to move themselves between rooms, and will be able to see who is in other rooms. (Note: Breakout room functionality works imperfectly with a smartphone or tablet. It’s best to use a computer for this.)

The speakers are Kristine Bauer (Calgary), Jeremy Hahn (MIT), and Kate Ponto (Kentucky).

4-hour online mini-course, offered on consecutive Tuesdays and Thursdays at 11:30am Eastern Time.

Speaker: Sander Kupers, University of Toronto Title: An introduction to homological stability

I warmly invite you to attend the following short course:

Title: Noncommutative Hodge-to-de Rham degeneration.

Speaker: Dmitry Kaledin (Steklov Institute).

Abstract: I am going to give an overview of the proof of what is known as "non-commutative Hodge-to-de Rham Degeneration Theorem": for any smooth and proper DG algebra over a field of characteristic 0, the Hochschild-to-cyclic spectral sequence degenerates at first term.

Dates: 7, 14 and 21 of May 2021 (Fridays) at 14:00-15:00 (GMT time).

Link: To appear soon. This event is open to all and will be streamed on Microsoft Teams.

Historical context (written by the organizer): In the eighties, Deligne and Illusie (following earlier work of Faltings), gave a purely algebraic proof of the degeneration of the classical Hodge-to-de Rham spectral sequence. Later, in the 00’s, Kontsevich and Soibelman conjectured that the noncommutative Hodge-to-de Rham spectral sequence (where smooth proper algebraic varieties are replaced by smooth proper dg algebras) should also degenerate. Recently, Kaledin proved Kontsevich-Soibelman’s conjecture. Kaledin’s proof makes use of several different tools from algebra, algebraic geometry, representation theory and algebraic topology. Therefore, I believe this short course to be of interest to a broad mathematical audience.

Organizer: Goncalo Tabuada

You are cordially invited to the 56th annual Cornell Topology Festival, which will be held online (for the first and hopefully only time ever!) this May. The main festival takes place Thursday May 20th – Friday, May 21st, 2021, with pre-festival talks on the 4th, 11th, and 18th, and a special colloquium on the 13th. More information about Zoom links, online social events, and discussion will follow for registered participants. We hope you will join us!

Speakers

Pre-Festival

Steve Trettel, Stanford University, 4 May 1pm; Lvzhou Chen, University of Texas Austin, 11 May 1pm; Sarah Koch, University of Michigan, Special Colloquium, 13 May 4pm; Jeremy Hahn, Massachusetts Institute of Technology, 18 May 1pm

20–21 May

Agnes Beaudry, University of Colorado Boulder; Sebastian Hensel, University of Munich; Kate Ponto, University of Kentucky; Manuel Rivera, Purdue University; Federico Rodriguez Hertz, Pennsylvania State University; Nick Salter, Columbia University; Richard Schwartz, Brown University; Matthew Stover, Temple University.

The 38th Annual Workshop in Geometric Topology will be held online June 15-17, 2021. The featured speaker will be Peter Bubenik of the University of Florida, who will give a series of three one-hour lectures on Topological Data Analysis.

Participants are invited to contribute talks of 20 minutes. Contributed talks need not be directly related to the topic of the principal lectures. Title and abstracts must be submitted by May 15. If there are more volunteers to speak than there are time slots, the organizers will choose talks that provide a balanced collection of topics and respect the historical traditions of the workshop. Earlier responses may be given some preference. Applicants will be notified whether their talk has been accepted by June 1.

Full details, including registration and information about submitting titles and abstracts for contributed talks, can be found at the conference web site at http://faculty.tcu.edu/gfriedman/GTW2021

The Workshops in Geometric Topology are a series of informal annual research conferences that have been held since 1984. In non-pandemic years, the workshops currently rotate among Brigham Young University, Calvin College, Colorado College, Texas Christian University, and the University of Wisconsin at Milwaukee. Each workshop features a series of three lectures by one principal speaker, providing a substantial introduction to an area of current research in geometric topology. Participants are invited to contribute short talks on their own research, and there is ample time set aside each day for informal interactions between participants. Funding for the workshop series is currently provided by a grant from the National Science Foundation (DMS-1764311).

Workshop Organizers: Fredric Ancel, University of Wisconsin-Milwaukee Greg Friedman, Texas Christian University Craig Guilbault, University of Wisconsin-Milwaukee Molly Moran, Colorado College Nathan Sunukjian, Calvin College Eric Swenson, Brigham Young University Frederick Tinsley, Colorado College Gerard Venema, Calvin College

Applied and computational topology, one of the most rapidly growing branches of mathematics, is becoming a key tool in applied sciences. It is making impact not only in mathematics, but on the wide interdisciplinary environment including material and medical sciences, data science, robotics. Building upon successful conferences held in Bedlewo in 2013 and 2017, the next edition of Applied Topology in Bedlewo will take place in 2021. Similarly as before, our aim is to bring together scientists from all over the world working in various fields of applied topology. This time we will focus on:

• random topology,
• topological methods in combinatorics,
• topological data analysis and shape descriptors,
• topological analysis of time-varying data in biology, engineering and finance,
• topological and geometrical descriptors of porous materials.

In this Masterclass, we will learn about the high dimensional cohomology of moduli spaces such as the moduli space of curves, graphs, and lattices. These moduli spaces are classifying spaces of groups such as mapping class groups, automorphism groups of free groups, and arithmetic groups. We will learn about duality groups whose high dimensional cohomology of these moduli spaces is related to the low degree homology groups with twisted coefficients. We will also discuss graph homology and tropical curves.

The masterclass is aimed at advanced graduate students and postdocs with an interest in algebraic topology and geometric group theory. Connections with algebraic geometry and number theory will be mentioned but this is not the primary focus.

Details see conference website.

This Conference has been organised in cooperation with the Society for Industrial and Applied Mathematics (SIAM).

Areas of interest include, but are not limited to: Topology. Kinematics. Algebraic topology of con?guration spaces of robot mechanisms. Topological aspects of path planning and sensor networks. Differential topology and singularity theory of robot mechanism and moduli spaces. Algebraic Geometry. Varieties generated by linkages and constraints. Geometry of stiffness and inertia matrices. Rigid-body motions. Computational approaches to algebraic geometry. Dynamical Systems and Control. Dynamics of robots and mechanisms. Simulation of multi-body systems, e.g. swarm robots. Geometric control of robots. Optimal control and other optimisation problems. Combinatorial and Stochastic Methods. Rigidity of structures. Path planning algorithms. Modular robots. Statistics. Stochastic control. Localisation. Navigation with uncertainty. Statistical learning theory. Cognitive Robotics. Mathematical aspects of Artificial Intelligence, Developmental Robotics and other Neuroscience based approaches.

Invited speakers: Dr Mini Saag – University of Surrey, UK Prof Frank Sottile - Texas A&M University, USA Prof Stefano Stramigioli - University of Twente, The Netherlands

A lattice is a discrete collection of regularly ordered points in space. Lattices are everywhere around us, from the patterned stacked arrangements of fruits and vegetables at the grocery to the regular networks of atoms in crystalline compounds. Today lattices find applications throughout mathematics and the sciences, applications ranging from chemistry to cryptography and Wi-Fi networks.

The focus of this meeting is the connections between lattices and number theory and geometry. Number theory, one of the oldest branches of pure mathematics, is devoted to the study properties of the integers and more sophisticated number systems. Lattices and number theory have many deep connections. For instance using number theory it was recently demonstrated that certain packings of balls in high dimensions are optimally efficient. Lattices also appear naturally when one studies certain spaces that play an important role in number theory; one of the main focuses of this meeting is to investigate computational and theoretical methods to understand such spaces and to expand the frontier of our algorithmic knowledge in working with them.

The cohomology of arithmetic groups is the study of the properties of ``holes'' in geometric spaces that contain information about number theory. The workshop will bring together mathematicians with expertise in number theory, topology, and geometric group theory to tackle these problems and explore recent developments.

We are happy to announce that the Institut Mittag-Leffler will be hosting a research program entitled

"HIGHER ALGEBRAIC STRUCTURES IN ALGEBRA, TOPOLOGY AND GEOMETRY”

from January 10, 2022 to April 29, 2022.

Junior researchers (advanced PhD students or young postdocs) can apply for a fellowship to attend the program, covering all expenses (deadline: December 31, 2020). For all others, the program is by invitation only.

Institut Mittag-Leffler in Danderyd, just north of Stockholm, Sweden, is an international centre for research and postdoctoral training in mathematical sciences. The oldest mathematical research institute in the world, it was founded in 1916 by Professor Gösta Mittag-Leffler and his wife Signe, who donated their magnificent villa, with its first-class library, for the purpose of creating the institute that bears their name.

Program web page: http://www.mittag-leffler.se/langa-program/higher-algebraic-structures-algebra-topology-and-geometry

Junior research fellowships: http://www.mittag-leffler.se/research-programs/junior-fellowship-program

The organizers
Gregory Arone ([email protected])
Tilman Bauer ([email protected])
Alexander Berglund ([email protected])
Søren Galatius ([email protected])
Jesper Grodal ([email protected])
Thomas Kragh ([email protected])