Calendar

< 2021 >
August 29 - September 04
  • 29
    August 29, 2021
    No events
  • 30
    August 30, 2021
    No events
  • 31
    August 31, 2021
    No events
  • 01
    September 1, 2021

    CMSA Quantum Matter in Mathematics and Physics Seminar: Naturalness and muon anomalous magnetic moment

    10:10 AM-11:40 AM
    September 1, 2021
    We study a model for explaining the apparent deviation of the muon anomalous magnetic moment, (g-2), from the Standard Model expectation. There are no new scalars and hence no new hierarchy puzzles beyond those associated with the Standard model Higgs; the only new particles that are relevant for (g-2) are vector-like singlet and doublet leptons. Interestingly, this simple model provides a calculable example violating the Wilsonian notion of naturalness: despite the absence of any symmetries prohibiting its generation, the coefficient of the naively leading dimension-six operator for (g−2) vanishes at one-loop. While effective field theorists interpret this either as a surprising UV cancellation of power divergences, or as a delicate cancellation between matching UV and calculable IR corrections to (g−2) from parametrically separated scales, there is a simple explanation in the full theory: the loop integrand is a total derivative of a function vanishing in both the deep UV and IR. The leading contribution to (g−2) arises from dimension-eight operators, and thus the required masses of new fermions are lower than naively expected, with a sizable portion of parameter space already covered by direct searches at the LHC. All of the viable parameter can be probed by the LHC and planned future colliders.

    https://harvard.zoom.us/j/977347126

  • 02
    September 2, 2021

    CMSA Quantum Matter in Mathematics and Physics Seminar: Exotic quantum matter: From lattice gauge theory to hyperbolic lattices

    10:30 AM-12:00 PM
    September 2, 2021

    This talk, in two parts, will discuss two (unrelated) instances of exotic quantum matter. In the first part, I will discuss quantum critical points describing possible transitions out of the Dirac spin liquid, towards either symmetry-breaking phases or topologically ordered spin liquids. I will also comment on the role of instanton zero modes for symmetry breaking in parton gauge theories. In the second part, I will propose an extension of Bloch band theory to hyperbolic lattices, such as those recently realized in circuit QED experiments, based on ideas from algebraic geometry and Riemann surface theory.

    https://harvard.zoom.us/j/977347126

  • 03
    September 3, 2021
    No events
  • 04
    September 4, 2021
    No events