Past Events

  • Condensed Matter Seminar: "Soft matter physics in the gut"

    David Rittenhouse Laboratory, A4

    Sujit S. Datta (Princeton University)

    The gut governs digestion and nutrient absorption, is a promising target for drug delivery, and teems with micro-organisms that can have remarkably strong effects on host health. Despite its importance, however, little is known about how the structure and function of the gut are influenced by many of the soft materials that transit through it regularly.

  • **CANCELLED** Astro Seminar: (TBA)

    David Rittenhouse Laboratory, A4


  • High Energy Theory Seminar: "Naturally Stabilizing the Weak Scale without Partners"

    David Rittenhouse Laboratory, 2N36

    Devin Walker (Dartmouth College)

    We generalize and adapt Veltman's condition to create a framework which naturally addresses the little hierarchy problem.  The resulting class of models is economical and ensures a minimum amount of fine-tuning for the bare Standard Model Higgs mass.  To demonstrate this framework, we provide a model with an extended Higgs sector and a top Yukawa coupling that is no longer unity.  The latter alleviates the largest radiative corrections to the Higgs mass.  The former features significant dimension-full coupl

  • Condensed Matter Seminar: "Mechanical Cell Biology of Microbes"

    David Rittenhouse Laboratory, A4

    Enrique Rojas (Stanford University)

    Research in microbial physiology has traditionally focused on understanding biochemical pathways and, more recently, on elucidating the surprisingly complex structure of microbial cytoplasm.  On the other hand, the whether mechanical forces also play a role in controlling sub-cellular processes in microbes has been overlooked. I will highlight several novel paradigms by which microbes use mechanical (and electrical) factors as signals to control cell growth, division, and survival, and highlight how the remarkable mechanical properties of the cells are critical for these p

  • **CANCELLED** Astro Seminar: "The Twisted Universe: The Cosmic Quest to Reveal Which End is Up"

    David Rittenhouse Laboratory, A4

    Brian Keating (UCSD)

    The cosmic microwave background (CMB) has spectacularly advanced our understanding of the origin, composition, and evolution of our universe. Yet there is still much to glean from this, the oldest light in the universe. Powerful telescopes are plying the skies in a quest to discover new physics. This talk concentrates on measurements by cutting-edge CMB telescopes which offer a glimpse into an exhilarating, and largely unexplored branch of astrophysics: the search for unique signatures in the polarization of the CMB.

  • Department Colloquium: "Results from the Dark Energy Survey"

    David Rittenhouse Laboratory, A8

    Gary Bernstein (University of Pennsylvania)

    The Dark Energy Survey (DES) is a collaboration between UPenn and 15 other institutions in 7 countries to construct and operate a new 500 megapixel CCD camera on the venerable 4-meter Blanco telescope in Chile. Its five-year mission: to survey 1/8 of the night sky in search of clues to the cause of the accelerating expansion of the Universe.


    David Rittenhouse Laboratory, Room A8

    Procotor will be on site


  • Condensed Matter Seminar: "Topological protection of photons"

    David Rittenhouse Laboratory, A4

    Mikael Rechtsman (Penn State University)

    Topological insulators are solid-state materials whose transport properties are immune to defects and disorder due to underlying topological order.  Perhaps the first such phenomenon was the quantum Hall effect, wherein the Hall conductivity is quantized and hence extremely robust.  In this talk, I will present the experimental observation of the topological protection of the transport of photons (rather than electrons in the solid state) in complex dielectric structures.  I will then present the obser

  • HET & HEE Joint Seminar: (TBA)

    Center for Particle Cosmology

    Josh Ruderman (NYU)

  • Rittenhouse Lecture: "GW170817: Hearing and Seeing a Binary Neutron Star Merger"

    David Rittenhouse Laboratory, A8

    Daniel Holz (Enrico Fermi Institute and Kavli Institute for Cosmology, U of Chicago) hosted by Bhuvnesh Jain

    With the discovery of GW170817 in gravitational waves, and the discovery of an associated short gamma-ray burst, and the discovery of an associated optical afterglow, we have finally entered the era of gravitational-wave multi-messenger astronomy. We will discuss LIGO/Virgo's detection of this binary coalescence, and explore some of the scientific implications, including confirmation of the kilonova model and implications for the origin of gold and platinum in the universe, tests of general relativity, and the first standard siren measurement of the Hubble constant.