seminars:topsem
Differences
This shows you the differences between two versions of the page.
|
seminars:topsem [2025/09/17 16:51] lruffoni |
seminars:topsem [2025/12/21 06:25] (current) lruffoni |
||
|---|---|---|---|
| Line 9: | Line 9: | ||
| <select id="setit" style="color: #0000FF" size="1" name="test"> | <select id="setit" style="color: #0000FF" size="1" name="test"> | ||
| <option value="">Previous seminars</option> | <option value="">Previous seminars</option> | ||
| + | <option value="http://www2.math.binghamton.edu/p/seminars/topsem/topsem_fall2025">Fall 2025</option> | ||
| <option value="http://www2.math.binghamton.edu/p/seminars/topsem/topsem_spring2025">Spring 2025</option> | <option value="http://www2.math.binghamton.edu/p/seminars/topsem/topsem_spring2025">Spring 2025</option> | ||
| <option value="http://www2.math.binghamton.edu/p/seminars/topsem/topsem_fall2024">Fall 2024</option> | <option value="http://www2.math.binghamton.edu/p/seminars/topsem/topsem_fall2024">Fall 2024</option> | ||
| Line 36: | Line 37: | ||
| </html> | </html> | ||
| - | ====== Fall 2025 ====== | + | ====== Spring 2026 ====== |
| - | * **August 28th** \\ Speaker: ** Cary Malkiewich (Binghamton) ** \\ Title: ** Higher scissors congruence | + | * **January 22nd** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | ** <WRAP box>// Abstract: // Scissors congruence is the study of polytopes, up to the relation of cutting into finitely many pieces and rearranging the pieces. In the 2010s, Zakharevich defined a "higher" version of scissors congruence, where we don't just ask whether two polytopes are scissors congruent, but also how many scissors congruences there are from one polytope to another. | + | |
| - | Zakharevich's definition is a form of algebraic K-theory, which is famously difficult to compute, but I describe some recent work that makes these calculations possible, at least for low-dimensional geometries. This allows us to compute the homology of the group of cut-and-paste operations in new cases, including the group of interval exchange transformations, and a new proof of Szymik and Wahl's theorem that Thompson's group V is acyclic. | + | * **January 29h** \\ Speaker: ** Juliet Aygun (Cornell) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | Much of this talk is based on joint work with Anna-Marie Bohmann, Teena Gerhardt, Mona Merling, and Inna Zakharevich, and also with Alexander Kupers, Ezekiel Lemann, Jeremy Miller, and Robin Sroka. \\ </WRAP> | + | * **February 5th** \\ Speaker: ** Barry Minemyer (Commonwealth University - Bloomsburg) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | * **September 4th** \\ Speaker: ** Liz Tatum (Rochester) ** \\ Title: ** Some applications of equivariant Brown-Gitler spectra ** <WRAP box>// Abstract: // In the 1980s, Mahowald and Kane used integral Brown-Gitler | + | * **February 12th** \\ Speaker: ** Sanjana Agarwal (Indiana University, Bloomington) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | spectra to construct splittings of the cooperations algebras for ko, | + | |
| - | connective real k-theory, and ku, connective complex k-theory. These | + | * **February 19th** \\ Speaker: ** Satya Howladar (University of Florida) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | splittings helped make it feasible to do computations using the ko- and | + | |
| - | ku-based Adams spectral sequences. | + | |
| - | These spectral sequences have proven to be powerful tools for better understanding the structure of the stable homotopy groups of the sphere, with a variety of interesting applications. For example, Mahowald used them to verify the Telescope Conjecture at height one, and Gonzalez later used them to classify stunted lens spaces. | + | * **February 26th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | In this talk, I will discuss progress towards developing analogues of these tools in the C_2 equivariant setting. In particular, Guchuan Li, Sarah Petersen, and I have constructed models for C_2-equivariant analogues of the integral Brown-Gitler spectra, and used them to construct an analogue of the ku-splitting. \\ </WRAP> | + | |
| - | * **September 18th** \\ Speaker: **Lorenzo Ruffoni (Binghamton) ** \\ Title: **A Pontryagin sphere at infinity in real hyperbolic space ** <WRAP box>// Abstract: // Given a discrete group of isometries of hyperbolic space, we can look at its limit set, i.e., the set of accumulation points of its orbits on the sphere at infinity. This is a compact metric space embedded in the sphere at infinity, and it often displays interesting geometric and topological features that can reveal algebraic information about the group itself. | + | * **March 5th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | In this talk, first we will discuss the general theory and present classical examples of limit sets, including some simple fractals (Cantor set, Sierpinski carpet). Then, we will present the construction of groups whose limit set is a Pontryagin sphere. These groups are obtained as reflection groups, and the construction is based on the existence of certain right-angled hyperbolic polyhedra. This is joint work with S. Douba, G.-S. Lee, and L. Marquis. \\ </WRAP> | + | |
| + | * **March 12th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
| + | |||
| + | * **March 19th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
| - | * **September 25th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | * **March 26th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> |
| - | * **October 2nd** \\ No seminar \\ | + | * **April 2nd** <WRAP box>// // (Spring break - no seminar) \\ </WRAP> |
| - | + | ||
| - | * **October 9th** \\ Speaker: ** Liam Keenan (Brown University) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **October 16th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **October 23th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **October 30th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **November 6th** \\ Speaker: ** Genevieve Walsh (Tufts University) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **November 13th** \\ Speaker: ** Maximilien Peroux (Michigan State University) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **November 20th** \\ Speaker: ** David Chan (Michigan State University) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | * **November 27th** \\ No seminar \\ | + | |
| - | + | ||
| - | * **December 4th** \\ Speaker: **Hongbin Sun (Rutgers) ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | + | |
| - | + | ||
| - | + | ||
| + | * **April 9th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
| + | * **April 16th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
| + | * **April 23th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
| + | * **April 30th** \\ Speaker: ** ** \\ Title: ** ** <WRAP box>// Abstract: // \\ </WRAP> | ||
seminars/topsem.1758142296.txt · Last modified: 2025/09/17 16:51 by lruffoni