Past Events

  • Astronomy seminar: "The Hercules Stream: stars on Trojan orbits visiting the solar vicinity"

    David Rittenhouse Laboratory, A2

    Elena D’Onghia (University of Wisconsin-Madison)

    The origin of the stars with coherent velocities discovered in the solar neighborhood remains uncertain, but their dynamics and evolution are key to understanding the dynamics of the Galactic stellar disk and ultimately the history of the Milky Way. The Gaia satellite is currently mapping the phase-space of a few million stars in the solar neighborhood. About 350,000 stars within 200 pc of the Sun are identified in streams, bundles of stars that move together in the same direction with a velocity that is distinct from neighboring stars.

  • Special Seminar: "This Is Not A Diversity Talk"

    David Rittenhouse Laboratory, A8

    John Asher Johnson, Harvard University

    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.

  • High Energy Theory seminar: "Direct Detection of sub-GeV Dark Matter: A New Frontier"

    David Rittenhouse Laboratory, A8

    Rouven Essig, Stony Brook University

    Dark matter makes up 85% of the matter in our Universe, but we have yet to learn its identity.  While most experimental searches focus on Weakly Interacting Massive Particles (WIMPs) with masses above the proton (about 1 GeV/c^2), it is important to also consider other motivated dark-matter candidates.  Indeed, over the last decade, the theoretical landscape of possible dark-matter candidates has expanded significantly to consider masses from 10^-22 eV/c^2 up to the Planck mass, and even higher in the case of composite dark matter.  At the same time, many novel dark-ma

  • Condensed Matter seminar: "Fracton phase of matter: Lattice models, gauge theories and realizations"

    David Rittenhouse Laboratory, A4

    Yizhi You, Princeton University

    Fracton phase of matter shares many features of topological order, including long-range entangled ground states and non-trivial braiding statistics. At the same time, fracton phase contains subextensive ground-state degeneracy and the restricted mobility of quasiparticle which exclude itself from the TQFT paradigm. In this talk, I start from several solvable lattice models as candidates for Fracton order. Further, I will present a theoretical framework on higher rank Chern-Simons theory in 3D as the low energy effective theory for Fracton phase.

  • Dissertation Defense: "Measurement of Electroweak Production of Same-Sign W Boson Pairs with ATLAS

    DRL, Room 2C2

    William DiClemente

  • Eli Burstein Lecture in Materials Science: "Designing Superconductivity: Using nanostructures to manipulate interactions in a complex system"

    Glandt Forum (3rd Floor), Singh Center for Nanotechnology, 3205 Walnut Street

    Nadya Mason, University of Illinois at Urbana-Champaign

    One of the most fundamental scientific questions is how the macroscopic properties of matter emerge from complex interactions of microscopic constituents. In this talk, I will discuss a “bottom-up” approach to studying collective effects in matter via coupled nanostructures. In particular, I will show how large arrays of superconducting islands fabricated on normal metal films can act as model, tunable superconducting systems. By changing the size and configuration of the islands, we can tune the parameters relevant to superconductivity, such as disorder and dissipation.

  • Department Colloquium: Progress Toward a Solution of the “Supernova Problem”

    David Rittenhouse Laboratory, A8

    Anthony Mezzacappa, University of Tennessee

    The death of massive stars in core collapse supernova explosions are directly or indirectly responsible for the lion’s share of the elements in the periodic table, give birth to neutron stars and stellar mass black holes, and play a major role in the chemical and thermal evolution of their host galaxies. They are a quintessential modern physics application in which kinetic theory, weak- and strong-interaction physics, and relativity come together, microscopic and macroscopic physics joined hand-in-hand in surprising ways.

  • Dissertation Defense: "Development of Kinetic Inductance Detectors for Far-Infrared Astrophysics"

    DRL, Room 4C6

    Alyssa Barlis

  • Dissertation Defense: "Electron Identification, Electronics Upgrades, and Electroweak Supersymmetry at ATLAS"

    DRL, 4N12

    Joey Reichert

  • Experimental Particle Physics Seminar: "Jinping Neutrino Experiment"

    David Rittenhouse Laboratory, 4N12

    Shaomin Chen, Tsinghua University