Past Events

High Energy Theory seminar
February 18, 2019  2:00 pm  4:00 pm
David Rittenhouse Laboratory, 2N36
Lara Anderson, Virgina Tech

High Energy Theory seminar: "Holographic Entropy Cone with Time Dependence"
February 4, 2019  2:00 pm  4:00 pm
David Rittenhouse Laboratory, 2N36
Bartek Czech, Tsinghua University
In the AdS/CFT correspondence, if a CFT state is dual to a semiclassical spacetime, its entanglement entropies (minimal surface areas) must obey certain inequalities. The bestknown examples are the strong subadditivity of entanglement entropy (SSA) and the monogamy of mutual information (MMI). Together, such inequalities define the socalled holographic entropy cone.

High Energy Theory seminar: "Shift Symmetries in (A)dS"
January 28, 2019  2:00 pm  4:00 pm
David Rittenhouse Laboratory, 2N36
Kurt Hinterbichler, Case Western Reserve University
I will discuss the generalizations of shift symmetries, galileon symmetries, and extended galileon symmetries to (A)dS space and to higher spin. Unlike flat space, these symmetries are present only for particles with particular masses, and are related to partially massless symmetries. For the case of scalars, I will discuss nonlinear extensions of the symmetries and invariant interactions. This leads to a unique ghostfree theory in (A)dS space that is an (A)dS extension of the special Galileon.

High Energy Theory seminar: "Axion couplings and implications for cosmology and astrophysics"
December 10, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 2N36
JiJi Fan, Brown University
Many cosmological models rely on large couplings of axions (pseudoscalar fields) to gauge fields. Examples include theories of magnetogenesis, inflation on a steep potential, chiral gravitational waves, and chromonatural inflation.

High Energy Theory Seminar: "SYK, harmonic analysis, and multipoint conformal blocks"
December 3, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 2N36
Vladimir Rosenhaus, IAS, Princeton University

High Energy Theory Seminar: "Gaugefield inflation and the origin of the matterantimatter asymmetry"
November 26, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 2N36
Peter Adshead, University of Illinois, Urbana Champaign
In this talk, I describe a new class of inflationary scenarios which utilize gauge fields to generate inflationary dynamics in the early universe. Beyond simply providing yet another model for inflation, these scenarios furnish unique observational imprints which distinguish them from standard scalarfield scenarios.

High Energy Theory Seminar: "NewmanPenrose and BMS Charges Near Null Infinity"
November 13, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 4N12
Chris Pope, Texas A&M University
In 1965 Newman and Penrose (NP) showed that any asymptoticallyflat spacetime admits 10 quantities, obtained as certain sphericalharmonic projections of a particular component of the Weyl tensor, which are exactly conserved on future null infinity. In the same era, the BMS group of symmetries of asymptotically flat spacetimes was being extensively studied, primarily motivated by the goal of better understanding gravitational waves.

High Energy Theory Seminar: "Black Hole Microstate Cosmology"
November 12, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 2N36
Brian Swingle, University of Maryland, College Park
I will discuss the possibility that certain highenergy holographic CFT states correspond to black hole microstates with a geometrical behindthehorizon region, modelled by a portion of a second asymptotic region terminating at an endoftheworld (ETW) brane. The ETW boundary geometry takes the form of a closed FRW spacetime, and, in many cases, this behindthehorizon physics can be probed directly by looking at the time dependence of entanglement entropy for sufficiently large spatial CFT subsystems.

High Energy Theory Seminar: "Pulling the Holographic Boundary into the Bulk"
October 1, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 2N36
Yasunori Nomura, University of California Berkeley

Special High Energy Theory Seminar: "Primordial black holes as dark matter"
September 28, 2018  2:00 pm  3:00 pm
David Rittenhouse Laboratory, 4N12
Alex Kusenko, UCLA
I will discuss new and rather generic scenarios for production of black holes in the early universe. In some mass range, such black holes can account for all dark matter. Primordial black holes can also contribute to synthesis of heavy elements by disrupting neutron stars.