Past Events

  • Experimental Particle Physics Seminar: "Anomaly of Dancing Reactor Antineutrinos"

    David Rittenhouse Laboratory, 3C8

    Soo-Bong Kim, Seoul National University

    The Reactor Experiment for Neutrino Oscillation(RENO) started data-taking from August, 2011 and has observed the disappearance of reactor electron antineutrinos to measure the smallest neutrino mixing angle theta13. The experiment has analyzed roughly 2200 days of data to make an accurate measurement of the oscillation amplitude and frequency based on energy and baseline dependent disappearance of reactor antineutrinos.

  • Condensed Matter Seminar: "Learning force fields from stochastic trajectories"

    David Rittenhouse Laboratory, A6

    Pierre Ronceray, Princeton University

    From nanometer-scale proteins to micron-scale colloidal particles, particles in biological and soft matter systems undergo Brownian dynamics: their deterministic motion due to the forces competes with the random diffusion due to thermal noise. In the absence of forces, all trajectories look alike: the key information characterizing the system's dynamics thus lies in its force field. However, reconstructing the force field by inspecting microscopy observations of the system's trajectory is a hard problem, for two reasons.

  • Astronomy seminar: "Two instruments to start the new decade: HERA for 21cm cosmology and SPARCS to Monitor M-Dwarf flares affecting exoplanets"

    David Rittenhouse Laboratory, A6

    Daniel Jacobs, Arizona State University

    Two new kinds of instruments are coming of age at the end of this decade: low frequency radio telescopes and cubesats, both being used to probe questions of our cosmic origin and the nature of exoplanets. The redshifted 21 cm hydrogen line is a unique probe of the early universe. A recent putative detection by EDGES, of a larger than expected signal, raises more questions. The Hydrogen Epoch of Reionization Array (HERA) is designed to answer these questions by providing high significance detection of fluctuations in the redshift range 6 to 20.

  • High Energy Theory Seminar: "Entanglement in gauge theories and gravity"

    David Rittenhouse Laboratory, 2N36

    Jennifer Lin, IAS, Princeton University

    In this talk I'll explain why an analogy between entanglement entropy in an emergent gauge theory and in AdS/CFT suggests that the entropy of a black hole may be related to a natural measure on the gauge group in the bulk. I will then provide an explicit example of this in Jackiw-Teitelboim gravity.

  • High Energy Theory Seminar: "Complementarity from Identity"

    David Rittenhouse Laboratory, 2N36

    Sergei Dubovsky, New York University

  • Department Colloquium: “A New Era of Science at Jefferson Lab”

    David Rittenhouse Laboratory, A8

    Robert McKeown, Deputy Director for Science, JLAB

    The continuous electron beam accelerator facility at Jefferson Lab, built with advanced superconducting radiofrequency (SRF) technology, provides opportunities to discover fundamental new aspects of the structure of visible matter – protons, neutrons and other states, and of the strong interaction, described by the gauge theory Quantum Chromodynamics.  The recent upgrade of the facility brings new opportunities, not only in the study of hadronic matter, but also in searches for new physics, such as a suite of experiments to search for massive “dark photons”.  This presentation
  • High Energy Theory Seminar: "Analytic IR-resummation for the BAO peak"

    David Rittenhouse Laboratory, 2N36

    Matthew Lewandowsky, Institut de Physique Théorique (IPhT)

    We develop an analytic method for implementing the IR-resummation of 1404.5954, which allows one to correctly and consistently describe the imprint of baryon acoustic oscillations (BAO) on statistical observables in large-scale structure. We show that the final IR-resummed correlation function can be computed analytically without relying on numerical integration, thus allowing for an efficient and accurate use of these predictions on real data in cosmological parameter fitting.

  • High Energy Theory Seminar: "Interfaces and Topological Entanglement in Abelian Chern-Simons Theory"

    David Rittenhouse Laboratory, 4N12

    Jackson Fliss, University of Illinois, Urbana Champaign

    Starting from the condensed matter context, we consider the ground state entanglement across (possibly distinct) topological phases separated by a gapped interface.  I will explain how addressing this from the effective gauge theory illuminates some generic features of entanglement entropy in systems with gauge invariance.  In particular, we will explicitly implement the "extended Hilbert space" prescription directly in the continuum as well as highlight the unique role of the Ishibashi state in Chern-Simons entanglement.  Time permitting, I will discuss exten

  • Condensed Matter Seminar: "Soft Matter Physics of the Evolution of Multi-Cellularity"

    David Rittenhouse Laboratory, A6

    Peter Yunker, Georgia Institute of Technology

    The evolution of multicellularity set the stage for an incredible increase in the diversity and complexity of life on Earth. The increase in biological complexity associated with multi-cellularity required parallel innovation in the mechanical properties of multi-cellular bodies. Though a cursory review of any multi-cellular organism provides an appreciation of this intertwining of biological and mechanical complexity, little is known about how such mechanical properties may have evolved.

  • Astronomy seminar: "Cosmological Seed Magnetic Field from Inflation"

    David Rittenhouse Laboratory, A6

    Bharat Ratra, Kansas State University

    A cosmological magnetic field of nG strength on Mpc length scales could be the seed magnetic field needed to explain observed few microG large-scale galactic magnetic fields. I first briefly review the observational and theoretical motivations for such a seed field, two galactic magnetic field amplification models, and some non-inflationary seed field generation scenarios. I then discuss an inflation magnetic field generation model. I conclude by mentioning possible extensions of this model as well as potentially observable consequences.