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Colloquia & Seminars
  • Applied Dynamics Seminar
    Speaker Name: Julian Candia

    Speaker Institution : UMD

    Title : Unbiased Learning from Big Data: Multidimensional Approaches for Data-Driven Biomedical Research
    When: Thu, April 24, 2014 - 12:30pm
    Where: IREAP Large Conference Room (ERF 1207)
  • Refreshments for CNAM Colloquium

    When: Thu, April 24, 2014 - 1:30pm
    Where: Phys Room 1305F
  • Nuclear Physics Seminar
    Title: Electromagnetic form factors of the octet baryons from lattice QCD

    Speaker: Phiala Shanahan, Adelaide

    Abstract: I will present the results of recent lattice simulations of the electromagnetic form factors of the octet baryons from the CSSM/QCDSF/UKQCD collaborations. The focus will be on the analysis of those results using techniques to approach the infinite volume limit and the physical pseudoscalar masses at non-zero momentum transfer. The extrapolated proton and neutron form factors are found to be in excellent agreement with those extracted from experiment. Given the success of these calculations, I will describe how the strange electromagnetic form factors may be estimated from these results under the same assumption of charge symmetry used in experimental determinations of those quantities. Motivated by the necessity of that assumption, I will explore a method for determining the size of charge symmetry breaking effects using the same lattice results discussed previously.
    When: Thu, April 24, 2014 - 1:30pm
    Where: 3150 PSC
  • CNAM Colloquium
    Speaker: Jonathan Denlinger, Advanced Light Source, Lawrence Berkeley
    National Laboratory

    Title: Thermal gap destabilization and the fate of topologically protected surface states in the mixed valent insulator SmB6

    Abstract: The paradigm mixed-valent insulator SmB_6 has experienced recent renewed
    interest coming from the prediction of the existence of topological surface states arising from the inversion of f and d-bands at the X-point, and from transport measurements giving evidence for surface conductivity at low temperatures. The existence of such surface states
    would provide an explanation for a 30 year puzzle as to the origin of “in-gap” states causing a metallic resistivity saturation below 4K. In this work angle-resolved photoemission on cleaved <100> surfaces provides the first experimental view of the X-point conduction band, the T-dependent destabilization of the many-body hybridization gap and the intimately connected fate of the topologically protected X-point surface
    states that reside in the gap [1]. The T-dependent evolution of the bulk states compares very well with bulk transport properties and the qualitative implications of DFT+DMFT calculations.But presently there is no such theory for the surface states.Spatial variations of the surface state properties and the extent of their robustness on inhomogeneous
    cleaved surfaces arising from large charge polarity differences between Sm- and B-terminated regions is also presented [2].

    [1] J.D. Denlinger, et al., /arXiv/:1336.6637;
    [2] J.D. Denlinger, et al. /arXiv/:1336:6636.

    Hosts: J. Paglione & N. Butch
    When: Thu, April 24, 2014 - 2:00pm
    Where: Phys Room 1201
  • Super-Riemann Surfaces, Part 2
    Speaker: Paul Green (UMCP)
    Abstract: We will continue the discussion of super-Riemann surfaces and the super-Virasoro and super-Novikov-Krichever algebras
    When: Thu, April 24, 2014 - 3:00pm
    Where: Physics 4208
  • Materials Science and Engineering Seminar
    Speaker Name: Eckhard Quandt

    Speaker Institution : Institute for Materials Science, Christian-Albrechts-Universität, Kiel, Germany

    Title : Superelastic TiNi Thin Film Medical Implants

    Abstract : Shape memory alloys based on binary equiatomic TiNi exhibits superelastic properties with superelastic strains larger than 8%, tensile strengths up to 1400 MPa, and breaking elongations up to 60%. Additionally, the material is known to reveal an excellent biocompatibility. Both features result in a high attractiveness for its use for medical implants and devices, as, e.g., for example stents. For further miniaturization of medical implant, e.g., for neurostents, thin film technology has gained increasing interest in comparison to traditional bulk fabrication routes.

    This presentation will cover the fabrication of micropatterned freestanding TiNi thin films, will discuss the mechanical and the fatigue properties in comparison to traditional bulk TiNi, will show the new possible functionalities of thin film stents and will present a method to fabricate NiTi thin film leaflets for transcatheter aortic valve replacements.

    Funding by the DFG (German Science Foundation) is gratefully acknowledged.
    When: Fri, April 25, 2014 - 1:00pm
    Where: Room 2110 Chemical & Nuclear Engineering Building
  • JQI Seminar
    Speaker Name: Vanderlei Bagnato

    Speaker Institution: Instituo de Fisica de Sao Carlos - University of S. Paulo

    Abstract: In this seminar we shall describe the observation of superfluid turbulence
    in an atomic trapped sample of Rb. Description of excitation, final side
    effect, and hydrodynamic properties will be presented. Simulations that
    justify the experimental observations will be presented. In a second part
    of the seminar, the possibility to describe the thermodynamics of a trapped
    superfluid using global ( in instead of local) variables will be discussed.
    Measurement of heat capacity, compressibility and the evidences of
    complementarities between pressure and volume will be discussed.

    Host: Luis Orozco
    When: Mon, April 28, 2014 - 11:00am
    Where: CSS 2400
  • Nuclear Physics Seminar
    Speaker: Shailesh Chandrasekharan, Duke

    Title: Sign Problems, Fermion Bags and a New Origin for Fermion Mass.

    Abstract: We discuss a new approach to solve fermion sign problems called
    the fermion bag approach. The idea is to collect fermion degrees
    of freedom within certain space-time regions (called fermion bags)
    and sum only over fermion world lines within this region. The summation
    over these world lines then gives the Boltzmann weight of the fermion
    bag. There are many interesting models where the fermion bag weights
    turn out to be positive. Sign problems in many of these models could
    not be solved earlier with traditional methods.

    In addition to solving new sign problems, the fermion bag approach also
    provides insight into the physics of fermion mass generation. For example,
    it seems possible that massless fermions can become massive not only
    through the formation of a fermion bilinear condensate as usual, but also
    through a new mechanism where the fermion condensate remains zero.
    We provide numerical evidence for the latter scenario in a three dimensional
    lattice four-fermion model.
    When: Mon, April 28, 2014 - 1:30pm
    Where: PSC 3150
  • EPT Seminar
    Joint Particle theory-experiment Maryland-Hopkins Seminar

    Seminar will be preceded by lunch at 12:30 pm. The talk is from 2:00 to 3:00 pm. Times are tentative.

    Title: Exotic Higgs Sectors

    Speaker: David Curtin, Stonybrook

    Abstract: I review the LHC road map for using the higgs discovery as a possible gateway to discovering BSM physics. There is a clear opportunity for discovery that has so far been under-utilized, which is the study of exotic higgs decays. We have recently published a large survey document to help guide a systematic experimental effort searching for these signatures. I discuss the extensive theory motivation for such a program, as well as discovery reach in many different channels. There are many searches that are particularly motivated using early LHC run 1 data.
    When: Mon, April 28, 2014 - 2:00pm
    Where: Bloomberg Hall, John's Hopkins University
  • Space and Cosmic Ray Physics Seminar
    Speaker Name: Greg Sullivan

    Speaker Institution : University of Maryland, Physics

    Title: Recent Results on the Observation of High Energy Astrophysical Neutrinos from IceCube

    Abstract: I present the latest results on the observation of high energy astrophysical neutrinos using the IceCube neutrino telescope deployed at the Antarctic South Pole Station. The IceCube detector instruments one cubic kilometer of deep ice and was finished with construction in December 2010, with operation of the completed detector starting in May 2011. Since that time IceCube has made the world's first observation of a diffuse flux of high energy neutrinos of non-terrestrial origin. This first evidence was published in the Journal Science in Fall 2013. Since that ground breaking initial result we have added data in both new analysis channels and the original analysis that further support our original evidence. IceCube has also made significant scientific contributions to the astrophysical theory of neutrino production in gamma-ray bursts (GRB). While GRB were a favored candidate for the yet unknown source of the highest energy cosmic rays, in 2012 IceCube published a result in the journal Nature that essentially ruled ruled out gamma-ray bursts as the sole source of these cosmic rays. I also present the current status of the evolving theory and data in the search for high energy neutrino emission from GRB. Finally, I will describe current thinking and potential next stage experimental programs to further our capability for performing high energy neutrino astrophysics and astronomy now that we have observed a non-zero flux astrophysical flux of neutrinos.
    Notes: Tea and Cookies 4:15-4:30 pm
    When: Mon, April 28, 2014 - 4:30pm
    Where: CSS 2400
  • Biophysics - No Seminar Held Today

    When: Sun, April 27, 2014 - 8:00pm
  • Informal Statistical Physics seminar
    Speaker Name: Professor Jan Sengers

    Speaker Institution : University of Maryland, College Park

    Title : Thermal Fluctuations in Nonequilibrium Thermodynamics: A Continuing Saga
    When: Tue, April 29, 2014 - 1:15pm
    Where: Room 1116, IPST Building, Bldg 85
  • Physics Colloquium
    Speaker name: Debra Fischer

    Speaker Institution: Yale University

    Title: The Search For 100 Earths

    Abstract: The search for planets orbiting nearby stars has been one of the greatest success stories of the past decade, with hundreds of discoveries being made using Doppler, transit, microlensing, and direct imaging techniques and thousands of candidates detected with NASA’s Kepler mission. Exoplanet detections have launched a subfield of astronomy that includes host star characterizations, measurements of planet radii and density, studies of atmospheres, interior structure, formation theory, and orbital evolution.
    The search for exoplanets is motivated by the question of whether life exists elsewhere. This drives our interest in the detection of planets that are similar to our own world: rocky planets with the potential for liquid surface water and plate tectonics; worlds that might harbor life that we can recognize. Importantly, we will need to discover not just a few, but hundreds of these worlds to eventually gain a statistical understanding of whether life is rare, common, or ubiquitous and ground-based telescopes offer an ideal platform for carrying out decade-long surveys. It is critical for follow-up studies (imaging, atmospheric studies) that these planets orbit nearby stars. In this talk, I will discuss how we plan to take what we've learned and push on to the next frontier: our plans for a next generation spectrograph, EXPRES, to carry out a search 100 Earths with the Discovery Channel Telescope.
    When: Tue, April 29, 2014 - 4:00pm
    Where: PHYS 1412
  • Nuclear Physics Seminar
    Title: TBA

    Speaker: Kostas Orginos, College of William & Mary

    Abstract: TBA
    When: Wed, April 30, 2014 - 11:30am
    Where: PSC 3150
  • Gravity Theory Seminar
    Speaker: Luc Blanchet, IAP

    Title: Recent developments on post-Newtonian computations of compact binary inspiral

    Abstract: The forthcoming detection and analysis of gravitational waves
    generated by compact binary systems (neutron stars and black holes) relies
    on the availability of gravitational wave templates ---
    i.e. the basic predictions from general relativity (weighted by the power
    density of noise in a given detector). In this talk we shall recall how a
    combination of analytical post-Newtonian approximations and numerical
    methods permits to build accurate and reliable templates for compact
    binary coalescence, that are used in the data analysis of the current
    network of detectors. We shall then discuss two more recent topics. First,
    the comparison of post-Newtonian predictions with those based on black
    hole perturbation theory and notably the self-force approach. Related to
    that is the recent use of the so-called first law of point particle
    dynamics that we shall explain. Second, the
    inclusion of high order spin-orbit effects both in the dynamics
    (i.e. the equations of motion) and the gravitational wave field, which
    dictates the orbital phase evolution, of black hole binaries,
    including the effects of spin and orbital precession.
    When: Wed, April 30, 2014 - 1:30pm
    Where: PSC 3150
  • Board of Visitors Seminar
    College of Computer, Mathematical, and Natural Sciences
    Board of Visitors Seminar
    Physics of Medical Devices
    by Dr. Robert E. Fischell

    *Limited Space available
    When: Wed, April 30, 2014 - 4:00pm
    Where: PSC 2136
  • Refreshments for CNAM Colloquium

    When: Thu, May 1, 2014 - 1:30pm
    Where: Phys room 1305F
  • CNAM Colloquium
    Speaker: Chris Mariane, Columbia University

    Title & Abstract TBD

    Host: Nick Butch
    When: Thu, May 1, 2014 - 2:00pm
    Where: Phys Room 1201
  • Adinkras, Part 1
    Speaker: Jim Gates (UMCP)
    Abstract: An introduction to adinkras, which are a graphical representation of supersymmetry representations with 1-dimensional spacetime.
    When: Thu, May 1, 2014 - 3:00pm
    Where: Physics 4208
  • MCFP Colloquium
    Title: Inflationary Gravitational Waves: Recent Advances and Next Steps

    Speaker: Marc Kamionkowski, Johns Hopkins

    Abstract: The recent detection of the cosmic microwave background signature of inflationary gravitational waves is, if/when confirmed, simply stunning. I will discuss how the measurement is done, the recent detection, and its interpretation. I will then review next steps to be taken with future CMB experiments and with galaxy surveys.
    When: Fri, May 2, 2014 - 1:30pm
    Where: CSS 2400

Department of Physics

University of Maryland
College Park, MD 20742-4111
Phone: 301.405.3401
Fax: 301.314.9525