Calendar

< 2024 >
January 28 - February 03
  • 28
    January 28, 2024

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    January 28, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

  • 29
    January 29, 2024

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    January 29, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

  • 30
    January 30, 2024

    CMSA General Relativity Seminar: A quasi-local mass in general relativity

    11:00 AM-12:00 PM
    January 30, 2024
    20 Garden Street, Cambridge, MA 02138
    In this talk, we define a new gauge-independent quasi-local mass and energy with respect to the Minkowski spacetime. In contrast to other quasi-local masses, this new quasi-local mass/energy has a quasi-local proof of positivity. This positivity property is for spacelike surfaces with any topology. Moreover, we show that it has desired asymptotic behaviors at null and spatial infinity of asymptotically flat spacetimes. Rigidity is also established in that vanishing energy implies that the 2-surface arises from an embedding into Minkowski space, and conversely, the mass vanishes for any such surface. This is joint work with M. Khuri and S.T. Yau.

    Zoom: https://harvard.zoom.us/j/7855806609

    Password: cmsa

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    January 30, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

    Mathematical Picture Language Seminar: Inverse theorems and approximate structure

    4:30 PM-5:30 PM
    January 30, 2024

    We call a function f linear if f(x+y) = f(x) + f(y) holds for all x,y. It is natural to call f “99% linear” if instead, this identity holds for most pairs (x,y); say, 99% of
    pairs. Similarly, we could say f is “1% linear” if this identity holds 1% of the time. A natural question is then: what can we say about the structure of “99% linear” or “1% linear” functions? Are they always just perturbations of true 100% linear functions, or are there other examples?

    Given almost any algebraic definition, you can similarly ask about its approximate variants, and if you can prove a strong positive statement, it tends to have applications. In particular, I will discuss how 1% linear functions relate to the Polynomial Freiman-Ruzsa conjecture, and how 1% polynomial functions relate to the Inverse Theorem for the Gowers norms.

    Zoom QR Code & Link:
    https://harvard.zoom.us/j/779283357?pwd=MitXVm1pYUlJVzZqT3lwV2pCT1ZUQT09
    Passcode: 657361
    https://mathpicture.fas.harvard.edu/seminar

  • 31
    January 31, 2024

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    January 31, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

    Dynamics, Geometry and Moduli Spaces Seminar: Stretch maps, after Thurston

    4:00 PM-5:00 PM
    January 31, 2024

    See webpage for more details: https://people.math.harvard.edu/~ctm/sem/

     

    Richard P. Stanley Seminar in Combinatorics: The doubly asymmetric simple exclusion process

    4:15 PM-5:15 PM
    January 31, 2024

    The multispecies ASEP (mASEP) is a Markov chain in which particles of different species hop on a one-dimensional lattice. The doubly ASEP (DASEP) is like the mASEP, but it additionally allows spontaneous change of species. We will introduce two new Markov chains that the DASEP lumps to, which give relations between sums of steady state probabilities. We also give explicit formulas for the stationary distribution of a particular infinite family.

    ===============================

    For more info, see https://math.mit.edu/combin/

  • 01
    February 1, 2024

    CMSA Algebraic Geometry in String Theory Seminar: Algebraic billiards and dynamical degrees

    10:30 AM-11:30 AM
    February 1, 2024
    20 Garden Street, Cambridge, MA 02138

    Billiards is one of the most-studied dynamical systems, modeling the behavior of a point particle bouncing around some space. If the space is a plane region bounded by an algebraic curve, then we may use techniques from algebraic geometry to study its billiards map. We explain how to view billiards as a complex algebraic correspondence, and we prove upper and lower bounds on the dynamical degree, the growth rate of the degrees of the iterates, in terms of the degree of the boundary curve. These degree growth rates are studied in mathematical physics, broadly speaking, as a way to identify integrable (exactly solvable) physical models. In our setting, this theory gives us an upper bound on the entropy, or chaos, of billiards in curves.

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    February 1, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

    Thursday Seminar: Ravenel's Telescope Conjecture: Ambidexterity and chromatic cyclotomic extensions

    3:30 PM-5:30 PM
    February 1, 2024
    1 Oxford Street, Cambridge, MA 02138 USA

    This semester we will go through the work of Burklund, Hahn, Levy and Schlank on the construction of counterexamples to the telescope conjecture.

  • 02
    February 2, 2024

    CMSA Member Seminar: On complete Calabi-Yau metrics and Monge-Ampere equations

    12:00 PM-1:00 PM
    February 2, 2024-February 2, 2024

    Calabi-Yau metrics are central objects in K\”ahler geometry and also string theory. The existence of Calabi-Yau metrics on compact manifolds was answered by Yau in his solution of the Calabi conjecture, but the situation in the non-compact setting is much more delicate, and many questions related to the existence and uniqueness of non-compact Calabi-Yau metrics remain unanswered. I will give an introduction to this subject and discuss some ongoing joint work with T. Collins and S.-T. Yau, on a new relationship between complete Calabi-Yau metrics and a new Monge-Ampere equation.

    Friday, Feb. 2nd at 12pm, with lunch, lounge at CMSA (20 Garden Street). Also by Zoom: https://harvard.zoom.us/j/92410768363

  • 03
    February 3, 2024
    No events