Past Events

  • Experimental Partical Physics Seminar: "First results from the PROSPECT reactor neutrino experiment"

    David Rittenhouse Laboratory, 4N12

    Danielle Norcini, Yale University

    Experiments at nuclear reactors have played a key role in determining the properties of the weakly-interacting neutrinos. Results from recent reactor experiments suggest a disagreement between the observed antineutrino flux and energy spectrum when compared to predictions. Beyond the Standard Model sterile neutrinos and corrections to complex nuclear models have been posed to explain the discrepancy. To address this physics, the PROSPECT experiment precisely measures antineutrino energy spectra at multiple, very short baselines (< 10m) from the High Flux Isotope Reactor.

  • Rittenhouse Lecture: "The Planck Legacy: Inflation and the Origin of Structure in the Universe"

    David Rittenhouse Laboratory, A8

    George P. Efstathiou, University of Cambridge and Kavli Institute for Cosmology

    I will review the latest results on cosmic microwave background (CMB) anisotropies measured by the Planck satellite. These measurements agree extremely well with a spatially flat, cosmological constant dominated cosmology with nearly scale invariant Gaussian fluctuations,  as predicted by  inflationary models of the early Universe.

  • Dissertation Defense: "The Higgs from A_mu to Z_mu: Higgs boson cross section measurements using diphoton and four lepton decays at 13 TeV."

    David Rittenhouse Laboratory, 2N36

    Bijan Haney

  • High Energy Theory Seminar: "Newman-Penrose and BMS Charges Near Null Infinity"

    David Rittenhouse Laboratory, 4N12

    Chris Pope, Texas A&M University

    In 1965 Newman and Penrose (NP) showed that any asymptotically-flat spacetime admits 10 quantities, obtained as certain spherical-harmonic 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"

    David Rittenhouse Laboratory, 2N36

    Brian Swingle, University of Maryland, College Park

    I will discuss the possibility that certain high-energy holographic CFT states correspond to black hole microstates with a geometrical behind-the-horizon region, modelled by a portion of a second asymptotic region terminating at an end-of-the-world (ETW) brane. The ETW boundary geometry takes the form of a closed FRW spacetime, and, in many cases, this behind-the-horizon physics can be probed directly by looking at the time dependence of entanglement entropy for sufficiently large spatial CFT subsystems.

  • Special Seminar: "This Is Not A Diversity Talk" - POSTPONED MAKE UP DATE TBD

    David Rittenhouse Laboratory, A8

    John A. Johnson, The Harvard-Smithsonian Center for Astrophysics

    The American discourse on the various disparities present in society generally, and academia specifically, focuses primarily on observations of the state of a given situation---e.g. a lack of diversity---rather than on the actions that lead to such a state. This approach is just as dissatisfying and ultimately ineffectual as observing that certain stars are "bright," rather than describing any of the physical principles that lead to the observed properties of a star.

  • Condensed Matter Seminar: "Terahertz-frequency light fields driving quantum material electrons, ions, and spins"

    David Rittenhouse Laboratory, A6

    Keith Nelson, Massachusetts Institute of Technology

    Terahertz-frequency light pulses can now be generated routinely with field amplitudes sufficient to drive highly nonlinear responses of materials and molecules.

  • Experimental Particle Physics Seminar: "Short-range correlation studies in nuclei"

    David Rittehouse Laboratory, A8

    Or Hen, MIT

  • Astronomy seminar: "Measurements of Degree-Scale B-mode Polarization with the BICEP/Keck Experiments at South Pole"

    David Rittehouse Laboratory, A6

    Benjamin Racine, Harvard-Smithsonian Center for Astrophysics

    The BICEP and Keck experiments, located at the South Pole, are currently observing the polarized microwave sky at the degree scale using refractive telescopes. They are searching for a signature of primordial gravitational waves in the so-called B modes of the cosmic microwave background (CMB), parametrized with the tensor-to-scalar ratio r. In this talk I will introduce our latest analysis which includes BICEP2 and Keck array data up to the end of 2015.

  • Condensed Matter Seminar: "Adhering, wrapping, and bursting of fluid membranes: understanding effects of membrane-binding particles and polymers"

    David Rittenhouse Laboratory, A6

    Anthony (Tony) Dinsmore, University of Massachusetts, Amherst

    Proteins and membranes form remarkably complex structures that are key to intracellular compartmentalization, cargo transport, and cell morphology. Despite this wealth of examples in living systems, we still lack design principles for controlling membrane morphology in synthetic systems. With experiments and simulations, we show that even the simple case of spherical nanoparticles binding to lipid-bilayer membrane vesicles results in a remarkably rich set of morphologies that can be reliably controlled via the particle binding energy.