Past Events

  • High Energy Theory: New Frontiers in Particle Cosmology Pt.1

    David Rittenhouse Laboratory, 4N12

    The purpose of this meeting is to bring together experts working at the interface of cosmology, string theory and particle physics for a few days of informal talks and exchanges of ideas. The schedule will allow ample time for impromptu discussions and collaborations.

  • Department Colloquium *Special*: "Solving the Solar Neutrino Problem"

    David Rittenhouse Laboratory, A8

    Joshua Klein (UPenn) Hosted by Gene Beier

    We will discuss the work of the Sudbury Neutrino Observatory, and the Penngroup in particular, that provided the solution to the long-standing Solar Neutrino Problem and which has been recognized this year by the Nobel Prize and the Breakthrough Prize. Some discussion of the implications of thesemeasurements and future directions will also be presented.

  • Astro Seminar: "The Scale-Dependence of Halo Assembly Bias"

    David Rittenhouse Laboratoy, A6

    Tomomi Sunayama (Yale University)

    The clustering of dark matter halos is influenced by halo
    properties besides mass, a phenomenon referred to as halo assembly
    bias. It is because halos of the same mass in different environments
    have different assembly histories and cluster differently. There have
    been several studies showing such environmental effects on the linear
    bias of halos. The halo bias on small scales, however, is
    scale-dependent. I will present the first study of the
    scale-dependence of halo assembly bias using the depth of the

  • High Energy Theory Seminar: "TBA"

    David Rittenhouse Laboratory, 2N36

    Simone Giombi (Princeton)

  • Rittenhouse Lecture:" Expansion of the Universe seen by Hubble"

    David Rittenhouse Laboratory, A8

    Adam Reiss (JHU/STScI) Hosted by Adam Lidz

    The Hubble constant remains one of the most important parameters in the cosmological model, setting the size and age scales of the Universe.  Present uncertainties in the cosmological model including the nature of dark energy, the properties of neutrinos and the scale of departures from flat geometry can be constrained by measurements of the Hubble constant made to higher precision than was possible with the first generations of Hubble Telescope instruments.  Streamlined distances ladders constructed from infrared observations of Cepheids and type Ia supernovae with ruthle

  • Condensed Matter seminar: "Microfluidics of sugar transport in plants"

    Chemistry Building, Room 102

    Kaare H. Jensen, Technical University of Denmark

    Plants can rightly be called masters of microengineering. Their survival and successful reproduction depends on their ability to overcome a series of physical challenges during growth and when transporting matter over great distances. In this talk, we focus on the microfluidic network responsible for energy distribution (the phloem). We combine experiments on living plants and biomimetic microfluidic devices to elucidate the basic physical principles that govern sugar transport in plants.

  • Condensed Matter seminar: "Microfluidics of sugar transport in plants"

    Chemistry Building, room 102

    Kaare Jensen (TU of Denmark)

    Plants can rightly be called masters of microengineering. Their survival and successful reproduction depends on their ability to overcome a series of physical challenges during growth and when transporting matter over great distances. In this talk, we focus on the microfluidic network responsible for energy distribution (the phloem). We combine experiments on living plants and biomimetic microfluidic devices to elucidate the basic physical principles that govern sugar transport in plants.
  • High Energy Theory Seminar: "TBA"

    David Rittenhouse Laboratory, 2N36

    Eric Perlmutter (Princeton)

  • Special Condensed Matter seminar: "Topological gapped and gapless phases protected by nonsymmorphic lattice symmetries"

    DRL A2

    Chen Fang, Massachusetts Institute of Technology

    In the first part of the talk, I will show that a nonsymmorphic glide reflection symmetry can protect a new Z2 topological gapped phase in three-dimensions. Unlike topological insulators, this new phase can be realized in either spinful or spinless (or having full spin rotation symmetry) systems. I will show one realization in photonic crystals in detail. In the second part, I will discuss how nonsymmorphic symmetries can protect topological gapless phases, or topological semimetals.

  • Astro Seminar: "Overview of Planck Data and (Cosmological and Astrophyical) Results "

    DRL A6

    Graca Rocha (JPL)

    In this talk I will give an overview of Planck data and Cosmological and Astrophysical results: Temperature and polarization maps of the Cosmic Microwave Background radiation anisotropies, Power Spectra, Likelihoods and Parameters estimated from both Planck frequency maps and CMB maps. Constraints on scalar spectral index, n_s, optical depth due to reionization, \tau, and the scalar to tensor ratio, r, will be presented along with constraints on Non Gausssianity, NG, of the CMB fluctuations , its isotropy and low-l (large angular scales) anomalies. In addition main astrophysical res