Physics Events

  • Tuesday, September 19, 2017
    Pheno & Vino Seminar
    “Perspectives on Astrophysical Searches for Dark Matter”

    Location: Jadwin Hall, Room 303
    Time: 4:30 PM
    Speaker(s): Stefano Profumo, University of California, Santa Cruz

    Description: I will describe a few recent results and new directions in searching for the nature of dark matter as a particle with astronomical observations and with cosmic ray measurements.

  • Friday, September 22, 2017
    High Energy Theory Seminar
    “Correlation Functions in N=4 SYM From Integrability”

    Location: Bloomberg Lecture Hall
    Time: 1:45 PM
    Speaker(s): Shota Komatsu, Member, School of Natural Sciences, IAS

    Description: I will give an overview of the integrability-based approach to study correlation functions in planar N=4 SYM. The basic strategy is to "divide and conquer": We decompose the correlators of single-trace operators into fundamental objects called hexagon form factors, and compute each hexagon form factor by using integrability. I will firstdiscuss how the method works in three-point functions and then generalize it to higher-point functions. Time permitting, I will explain more recent developments and possible future directions.

  • Monday, September 25, 2017
    High Energy Theory Seminar
    “Conformal Field Theories and Three Point Functions”

    Location: Jadwin Hall, 4th Floor, PCTS Seminar Room
    Time: 2:30 PM
    Speaker(s): Subham Dutta Chowdhury, Indian Institute of Science

    Description: Conformal invariance allows additional unique parity-odd tensor-structures for three-point functions involving the stress tensor, T, and a conserved U(1) current, j, in 2+1 dimensional conformal field theories that violate parity, apart from the usual parity even structures. Following the conformal collider physics setup of Hofman and Maldacena, we put constraints on the parity violating as well as parity preserving parameters of a general CFT in d=3. We find that large N Chern-Simons theories coupled to a fundamental fermion/boson saturate the bounds that we have derived. An application of the conformal collider bounds is observed in the form of sum rules which puts constraints on spectral densities of any CFT at finite temperature. We derive spectral sum rules in the shear channel for conformal field theories at finite temperature in general d≥3 dimensions. We show that the sum rule can be written in terms the parity even Hofman-Maldacena variables t2, t4 which determine the three point function of the stress tensor. We then use collider constraints and obtain bounds on the sum rule which are valid in any CFT.

  • Tuesday, September 26, 2017
    Pheno & Vino Seminar
    “TBA”

    Location: Jadwin Hall, Room 303
    Time: 4:00 PM
    Speaker(s): David Mckeen, University of Pittsburgh

  • Thursday, September 28, 2017
    Hamilton Colloquium Series
    “Higher-spin Gravity and Conformal Field Theory”

    Location: Jadwin Hall, Room A-10
    Time: 4:00 PM
    Speaker(s): Simone Giombi, Princeton University
    Note: Host: Igor Klebanov -- Tea at 3:30 pm, Loung Area outside of Jadwin Hall A-10

    Description: Higher-spin gravity is a generalization of Einstein's general relativity, which involves towers of interacting massless fields of arbitrarily high spin. It has an infinite dimensional higher-spin gauge symmetry, and can be consistently constructed in the presence of a non-zero cosmological constant. I will give an overview of higher-spin gravity theories, with a focus on their role in the context of the AdS/CFT correspondence, a remarkable "holographic" duality between quantum gravity in anti-de Sitter (AdS) space and conformal field theory (CFT) in one less dimension. Higher-spin theories provide dual gravitational descriptions of some classic field theoretical models, such as the Wilson-Fisher fixed point of the O(N) vector model, and the Gross-Neveu model. Generalizations of the higher-spin AdS/CFT correspondence, which involve the Chern-Simons gauge theory, have suggested new boson-fermion dualities in two spatial dimensions. 
    http://phy.princeton.edu/events/donald-r-hamilton-colloquium-series

  • Friday, September 29, 2017
    High Energy Theory Seminar
    “An Upper Bound on Transport”

    Location: Jadwin Hall, 4th Floor, PCTS Seminar Room
    Time: 1:45 PM
    Speaker(s): Raghu Mahajan, Princeton University

    Description: The linear growth of operators in local quantum systems leads to an effective lightcone even if the system is non-relativistic. We show that consistency of diffusive transport with this lightcone places an upper bound on the diffusivity: Dv2τeq. The operator growth velocity v defines the lightcone and τeq is the local equilibration timescale, beyond which the dynamics of conserved densities is diffusive. We verify that the bound is obeyed in various weakly and strongly interacting theories. In holographic models this bound establishes a relation between the hydrodynamic and leading non-hydrodynamic quasinormal modes of planar black holes. Our bound relates transport data --- including the electrical resistivity and the shear viscosity --- to the local equilibration time, even in the absence of a quasiparticle description. In this way, the bound sheds light on the observed T-linear resistivity of many unconventional metals, the shear viscosity of the quark-gluon plasma and the spin transport of unitary fermions.

  • Monday, October 2, 2017
    High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): Grant Remmen, Caltech

  • Tuesday, October 3, 2017
    Pheno & Vino Seminar
    “TBA”

    Location: Jadwin Hall, Room 303
    Time: 4:00 PM
    Speaker(s): Robert Lasenby, Perimeter Institute

  • Thursday, October 5, 2017
    Special High Energy Theory Seminar
    “Contraints on Particle Physics and Inflation from Quantum Gravity Conjectures”

    Location: Bloomberg Lecture Hall
    Time: 1:45 PM
    Speaker(s): Irene Valenzuela, Max-Planck-Institut für Physik

    Description: Consistency with quantum gravity can have significant consequences on low energy physics. For instance, using the Weak Gravity Conjecture, it has been recently argued by Ooguri and Vafa that non supersymmetric stable AdS vacua are incompatible with quantum gravity. However, it is known that AdS vacua can appear from compactifying the Standard Model to 2 or 3 dimensions. By requiring the absence of these vacua we can put constraints on the SM and BSM spectra, obtaining a lower bound for the cosmological constant in terms of the neutrino masses. This can also be translated into an upper bound for the EW scale around the TeV range, bringing a new perspective into the issue of the EW hierarchy. Another example of a quantum gravity constraint refers to the size of the moduli space, constraining the scalar field range which is available before the effective theory breaks down due to the appearance of infinitely many exponentially light states. I will explain how this behaviour is also generic for axions in flux string compactifications once we take into account backreaction effects. This disfavours transplanckian excursions in string embeddings of the axion monodromy proposal used for Inflation or Cosmological Relaxation.

  • Thursday, October 5, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Eve Ostriker, Princeton University

  • Monday, October 9, 2017
    High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): Thomas Hartman, Cornell University

  • Tuesday, October 10, 2017
    Special High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 1:45 PM
    Speaker(s): Piljin Yi, Korean Institute for Advanced Study

  • Tuesday, October 10, 2017
    Pheno & Vino Seminar
    “Probing Axions with Neutron Star Inspirals and other Stellar Processes”

    Location: Jadwin Hall, Room 303
    Time: 4:00 PM
    Speaker(s): Anson Hook, Stanford University

    Description: In certain models of a QCD axion, finite density corrections to the axion potential can result in the axion being sourced by large dense objects.

    There are a variety of ways to test this phenomenon, but perhaps the most surprising effect is that the axion can mediate forces between neutron stars that can be as strong as gravity.  These forces can be attractive or repulsive and their presence can be detected by Advanced LIGO observations of neutron star inspirals.  By a numerical coincidence, axion forces between neutron stars with gravitational strength naturally have an associated length scale of tens of kilometers or longer, similar to that of a neutron star. Future observations of neutron star mergers in Advanced LIGO can probe many orders of magnitude of axion parameter space. Because the axion is only sourced by large dense objects, the axion force evades fifth force constraints. We also outline several other ways to probe this phenomenon using electromagnetic signals associated with compact objects.

  • Thursday, October 12, 2017
    Hamilton Colloquium Series
    “Protein Phase Transitions in and out of Cells”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Ned Wingreen, Princeton University

    Description: Biologists have recently come to appreciate that eukaryotic cells are home to a multiplicity of non-membrane bound compartments, many of which form and dissolve as needed for the cell to function. These dynamical “liquid droplets” enable many central cellular functions – from ribosome assembly, to RNA regulation and storage, to signaling and metabolism. While it is clear that these compartments represent a type of separated phase, what controls their formation, how specific biological components are included or excluded, and how these structures influence physiological and biochemical processes remain largely mysterious. I will discuss recent experiments on phase separated droplets both in vitro and in vivo, and will present theoretical results that highlight a novel “magic number” effect relevant to the formation and control of two-component phase separated liquid droplets.

  • Tuesday, October 17, 2017
    Pheno & Vino Seminar
    “Gamma-ray Constraints on Decaying Dark Matter and Implications for IceCube”

    Location: Jadwin Hall, Room 303
    Time: 4:00 PM
    Speaker(s): Nick Rodd, MIT

    Description: Utilising the Fermi measurement of the gamma-ray spectrum toward the inner Galaxy, I will explain how to derive some of the strongest constraints on dark matter lifetimes in the mass range from hundreds of MeV to above an EeV. The limits derived disfavour a decaying DM interpretation of the astrophysical neutrino flux observed by IceCube, and I will review why that possibility has received some attention in the literature recently.

  • Thursday, October 19, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Jason Petta, Princeton University

  • Thursday, October 26, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 2:00 PM
    Speaker(s): Juan Maldacena, Institute for Advanced Study

  • Monday, October 30, 2017
    High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): Kyle Cranmer, New York University

  • Tuesday, October 31, 2017
    PCTS Program
    “20 Years Later: The Many Faces of AdS/CFT”

    Location: Jadwin Hall, PCTS Room 407
    Time: 8:00 AM

    Description: Much of our current understanding of quantum gravity and of strongly coupled gauge theory comes from the AdS/CFT correspondence. This workshop celebrates the 20th anniversary of AdS/CFT. We will take stock of the past 20 years of progress in understanding the holographic dictionary, applications of the correspondence, implications for quantum gravity and strongly coupled field theories, as well as using lessons from AdS/CFT to understand holographic quantum gravity in a more general context.
    FREE,butREQUIREDREGISTRATIONisavailableonlineathttp://pcts.princeton.edu/pcts

  • Thursday, November 9, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): B. Andrei Bernevig, Princeton University

  • Monday, November 13, 2017
    High Energy Theory Seminar
    “Quantum Closed Superstring Field Theory and the Weil-Petersson Symplectic Geometry”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): Roji Pius, Perimeter Institute

    Description: String field theory is the refined definition of string theory, formulated in the language of quantum field theory. Unlike the conventional Polyakov  approach, it provides a well defined prescription for computing the scattering amplitudes in string theory, even when there is mass renormalization and quantum corrections to the background. Since, string field theory is based on an action, it also has the potential to open the door towards the nonperturbative regime of string theory. Unfortunately,  the biggest problem of closed string field theory is that simple tools for performing calculations are not readily available. In this talk, I shall a discuss a  calculable realization of closed superstring field theory, formulated by exploring the significant progress in the Weil-Petersson geometry of the moduli space of Riemann surfaces in recent years.

  • Tuesday, November 14, 2017
    Pheno & Vino Seminar
    “TBA”

    Location: Jadwin Hall, Room 303
    Time: 4:00 PM
    Speaker(s): Kaitlyn Schutz, University of California, Berkeley

  • Monday, November 27, 2017
    High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): TBA, TBA

  • Thursday, November 30, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Gilles Tarjus, Laboratory of Theoretical Physics of Condensed Matter of the Pierre et Marie Curie University

  • Tuesday, December 5, 2017
    Quantum Information and Black Holes

    Location: Wolfensohn Hall
    Time: 7:00 AM
    https://www.sns.ias.edu/quantum-information-workshop-2017

  • Wednesday, December 6, 2017
    Quantum Information and Black Holes

    Location: Wolfensohn Hall
    Time: 7:00 AM
    https://www.sns.ias.edu/quantum-information-workshop-2017

  • Thursday, December 7, 2017
    Hamilton Colloquium Series
    “TBA”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Tilman Pfau, Universität Stuttgart

  • Monday, December 11, 2017
    High Energy Theory Seminar
    “TBA”

    Location: Bloomberg Lecture Hall
    Time: 2:30 PM
    Speaker(s): Kurt Hinterbichler, Case Western Reserve University

    Description:
     

  • Thursday, December 14, 2017
    Hamilton Colloquium Series
    “Exploring Embryonic Patterning with Colonies of Human Embryonic Stem Cells”

    Location: Jadwin Hall, Room A10
    Time: 4:00 PM
    Speaker(s): Eric Siggia, Rockefeller University

    Description: Embryology at the beginning of the 21st century finds itself in a situation similar to neurobiology; the behavior of the component pieces is understood in some detail, but how they self-assemble to become life is still very hazy. There are hundreds of  molecules that enable cell communication and genetics defines their function by classifying aberrant embryos at a suitable intermediate stage of development, which is difficult for mammals and impossible for humans. Embryonic stem cells can be expanded indefinitely and in the context of the embryo give rise to all cells in the body. The colloquium will describe synthetic systems that coax these stem cells to recapitulate aspects of gastrulation, which is the process by which the embryo transforms from a sphere to a cylinder, builds its anterior-posterior and dorsal-ventral axes, and segregates cells into ectoderm (skin and neurons), mesoderm (muscle bones and blood), and endoderm (gut, lungs, pancreas, etc.) lineages.

  • Thursday, December 14, 2017
    Raymond and Beverly Sackler Lecture in Astrophysics
    “TBA”

    Location: McDonnell A02
    Time: 8:00 PM
    Speaker(s): Victoria Kaspi, McGill University