Past Events

  • Condensed Matter Seminar: "Magnetism in Amorphous Alloys"

    David Rittenhouse Laboratory, A4

    Frances Hellman (University of California at Berkeley)

    Most condensed matter textbooks start by introducing crystal symmetries and the periodic lattice as foundational to the field.  Yet, it has long been known that the amorphous structure supports ferromagnetism, superconductivity, and a host of other condensed matter properties.  Superconductivity theory was famously expanded from the original Bloch wave pairing to be described as pairing of electrons with time-reversed wavefunctions to enable explanation of superconductivity in amorphous systems where electrons in the normal state have a mean free path of approximately an

  • Astro Seminar: "Fundamental Physics from the Non-linear Universe"

    David Rittenhouse Laboratory, A4

    Marcel Schmittfull (IAS)

    The cosmology community is running a large program of galaxy surveys over the next 10 years. Our goal is to map out the properties of dark energy as a function of time, measure the sum of neutrino masses, and study the origin of the Universe with unprecedented precision. A key limitation for these efforts is how to extract cosmological information from small scales that are affected by nonlinear dynamics.

  • High Energy Theory Seminar: "A Toy Model of Axion Gauge Field Inflation"

    David Rittenhouse Laboratory, 2N36

    Robert Caldwell (Dartmouth College)

    We present a toy model of an axion gauge field inflation scenario that yields viable density and gravitational wave spectra. The scenario consists of an axionic inflaton in a steep potential that is effectively flattened by a coupling to a collection of non-Abelian gauge fields. The model predicts a blue-tilted gravitational wave spectrum that is dominated by one circular polarization, resulting in unique observational targets for cosmic microwave background (CMB) and gravitational wave experiments.

  • *Special Condensed Matter Seminar*: "Self-organization and Self-assembly in Bio-molecular Systems"

    David Rittenhouse Laboratory, A2

    Prof. Erwin Frey (University of Munich)

    Active matter is a fascinating new field in soft matter physics aiming to understand how interacting active particles self-organize into an intriguing set of patterns and collective non-equilibrium states. Superficially, flocks of animals, self-propelled microorganisms or cytoskeletal systems appear to display similar phenomenologies, hinting towards universal organizing principles.

  • Dissertation Defense: "Singlet Oxygen Dosimetry for Pleural Photodynamic Therapy"

    LRSM, Reading Room

    Michele Kim (U of Penn)

  • Physics Department Colloquium: "Cal-Bridge and CAMPARE/CHAMP: Engaging Underrepresented Students in Physics and Astronomy"

    David Rittenhouse Laboratory - A8

    Alex Rudolph (Cal Poly Pomona) hosted by: James Aguirre

    The level of participation by underrepresented minority (URM) and female students in physics and astronomy PhD programs is shamefully low (2-4% for URM v. 30% in the general population; 20% for women v. 50% in the general population). I will begin by discussing research into why these participation rates are so low for these groups, highlighting role the physics and general GRE tests play in suppressing diversity in our field, while providing little to no benefit in helping predict long-term success.

  • Dissertation Defense: "Rate and State Friction Laws for Interfacial Chemical Bond-induced Friction at the Nanoscale"

    David Rittenhouse Laboratory, 3W2

    Kaiwen (Kevin) Tian (U of Penn)

  • HET & HEE Joint Seminar: "Digging Deeper for New Physics in the LHC Data"

    Center for Particle Cosmology

    David Shih (Rutgers University)

  • PHYSICS & ASTRONOMY CAREER SEMINAR: 10 Essential Steps to Successful Job Hunting for Physics PhD Students

    David Rittenhouse Laboratory, 3W2

    Dr. Joseph Barber, Senior Associate Director (Penn Career Services)

    Whether you are applying for faculty positions or for jobs in the broad range of other industries/fields that value a STEM PhD, there is plenty you can and should be doing throughout your PhD to position yourself for success. Attend this session to get advice about what to do in your limited professional and career development time to understand yourself and your career goals, explore your career options, and to develop an effective job searching strategy.  

  • Condensed Matter Seminar: "The Case for an Exciton Metal in Bilayer Graphene"

    David Rittenhouse Laboratory, A4

    Michael Zaletel (Princeton University)

    Graphene based heterostructures have emerged as a pristine platform for exploring the interplay of symmetry, topology and non-Abelian excitations in the quantum Hall regime. I will begin with a theoretical review of the quantum Hall effect in bilayer graphene before discussing results in collaboration with the Young Lab at UCSB. Using in-situ control of the density and electro-magnetic fields, they find a rich phase diagram which features a plateau at half-filling of a Landau level with a gap several times larger than previously observed.