Past Events

  • Dissertation Defense:"Bulges and Disks in the Nearby Universe:Applications to Evolution and Formation of Galaxies"

    David Rittenhouse Laboratory, 4E19

    Alan Meert, University of Pennsylvania

  • Astro Seminar: CDM's Most Severe Small-scale Problem: The Ubiquity of Co-orbiting Satellite Galaxy Planes

    David Rittenhouse Laboratory A6

    Marcel Pawlowski (Case Western)

    Comparisons of observed satellite galaxies with CDM
    simulations have revealed numerous 'small-scale' problems. While the
    missing-satellites, the core-cusp and potentially even the
    too-big-to-fail problems might be solved by invoking baryonic
    processes such as feedback not incorporated in the initial
    simulations, the problem I will present lacks a viable solution in
    the CDM framework and became increasingly severe in recent years.
    The satellites of the Milky Way and of the Andromeda galaxy

  • Dissertation Defense:"Encoding of Ultrasonic Communication Signals in Rat Auditory Cortex"

    David Rittenhouse Laboratory, 3W2

    Isaa Carruthers, University of Pennsylvaniac

  • Department Colloquium: Einstein and Quantum Mechanics: It’s Not What You Think

    David Rittenhouse Laboratory A8 Refreshments available in DRL 2nd floor Faculty Lounge @ 3:30pm

    Douglas Stone, Yale

    Einstein is well known for his rejection of quantum mechanics in the form it emerged from the work of Heisenberg, Born and Schrodinger in 1926.  Much less appreciated are the many seminal contributions he made to quantum theory prior to his final scientific verdict: that the theory was at best incomplete.  In this talk I present an overview of Einstein’s many conceptual breakthroughs and place them in historical context.  I argue that Einstein, much more than Planck, introduced the concept of quantization of energy in atomic mechanics.

  • Advances in Biomedical Optics Seminar: "Optogenetic Tools for Controlling Biological Circuits"

    Donner Auditorium, Basement Donner Building- 3400 Spruce St.

    Professor Brian Chow (University of Pennsylvania)

    *Pizza to be served @ 11:45A* 

  • Condensed Matter Seminar: "Spin Fluctuations and Entanglement"

    DRL A4

    Ari Turner, Johns Hopkins University

    I will compare the effects of quantum and thermal fluctuations in a
    spin chain by calculating the probability distribution for spin
    fluctuations in a segment.

    The calculation will use the concept of an "entanglement Hamiltonian."
    The entanglement Hamiltonian can be used to identify topological phases,
    but I will show that it is helpful for long-wavelength correlations
    as well as topological ones.

    The entanglement Hamiltonian is an imaginary system that
    describes the correlations of the ground state.  It cannot be measured

  • MAKE-UP EXAMS

    David Rittenhouse Laboratory A1

    Phys & Ast make up exams are scheduled Wednesday, 1/21, 6:00=8:00, A1
    DRL, bring your i.d. 

  • Department Colloquium: Restoration of Early Sound Recordings using Optical Metrology and Image Analysis

    DRLA8

    Carl Haber, LBL

    Sound was first recorded and reproduced by Thomas Edison in 1877.  Until about 1950, when magnetic tape use became common, most recordings were made on mechanical media such as wax, foil, shellac, lacquer, and plastic.  Some of these older recordings contain material of great historical interest, may be in obsolete formats, and are damaged, decaying, or are now considered too delicate to play.

  • Condensed Matter Seminar: "Universally Slow"

    DRL A4

    Ariel Amir, Harvard University

    Glassy systems are very common in nature, from disordered electronic and magnetic systems to window glasses and crumpled paper. Among their key properties are slow relaxations to equilibrium without a typical timescale, and dependence of relaxation on the system's age. Understanding these phenomena is a long-standing problem in physics. After reviewing some of these physical systems, I will describe our approach to the problem, and show how it leads to a novel class of aging.

  • Department Colloquium: "Topological Boundary Modes from Quantum Electronics to Classical Mechanics"

    A8

    Professor Charles Kane (Univ of Penn)

    Over the past several years, our understanding of topological electronic phases of matter has advanced dramatically.