Now showing items 41954-41973 of 56883

    • Quantum Times: Physics, Philosophy, and Time in the Postwar United States 

      Crystal, Lisa (2013-09-18)
      The concept of time in physics underwent significant changes in the decades following World War II. This dissertation considers several ways in which American physicists grappled with these changes, analyzing the extent ...
    • Quantum Transport of Strongly Interacting Photons in a One-Dimensional Nonlinear Waveguide 

      Hafezi, Mohammad; Chang, Darrick E.; Gritsev, Vladimir; Demler, Eugene A.; Lukin, Mikhail D. (American Physical Review, 2012)
      We present a theoretical technique for solving the quantum transport problem of a few photons through a one-dimensional, strongly nonlinear waveguide. We specifically consider the situation where the evolution of the optical ...
    • Quantum Versus Classical Learnability 

      Servedio, Rocco A.; Gortler, Steven (Institute of Electrical and Electronics Engineers (IEEE), 2001)
      Motivated by work on quantum black-box query complexity, we consider quantum versions of two well-studied models of learning Boolean functions: Angluin's (1988) model of exact learning from membership queries and Valiant's ...
    • Quantum-Coherence-Enhanced Surface Plasmon Amplification by Stimulated Emission of Radiation 

      Dorfman, Konstantin E.; Jha, Pankaj K.; Voronine, Dmitri V.; Genevet, Patrice; Capasso, Federico; Scully, Marlan O. (American Physical Society, 2013)
      We investigate surface plasmon amplification in a silver nanoparticle coupled to an externally driven three-level gain medium and show that quantum coherence significantly enhances the generation of surface plasmons. Surface ...
    • Quantum-Critical Relativistic Magnetotransport in Graphene 

      Müller, Markus; Fritz, Lars; Sachdev, Subir (American Physical Society, 2008)
      We study the thermal and electric transport of a fluid of interacting Dirac fermions using a Boltzmann approach. We include Coulomb interactions, a dilute density of charged impurities and the presence of a magnetic field ...
    • Quantum-Dot-Based Resonant Exchange Qubit 

      Medford, J; Beil, J.; Taylor, J. M.; Rashba, Emmanuel; Lu, H.; Gossard, A. C.; Marcus, C. M. (American Physical Society (APS), 2013)
      We introduce a solid-state qubit in which exchange interactions among confined electrons provide both the static longitudinal field and the oscillatory transverse field, allowing rapid and full qubit control via rf ...
    • Quantum-fluctuation-induced time-of-flight correlations of an interacting trapped Bose gas 

      Lovas, Izabella; Dóra, Balázs; Demler, Eugene; Zaránd, Gergely (American Physical Society, 2017)
    • Quantum-mechanical Study of ro-vibrational Transitions in H2 Induced by He Atoms 

      Balakrishnan, N.; Forrey, R. C.; Dalgarno, A. (American Astronomical Society, 1999)
      We describe quantum-mechanical scattering calculations of re-vibrational transitions in H-2 induced by collisions with He. We use a close-coupled description of the dynamics which includes full re-vibrational coupling and ...
    • A Quantum-Quantum Metropolis Algorithm 

      Yung, Man-Hong; Aspuru-Guzik, Alan (National Academy of Sciences, 2012)
      The classical Metropolis sampling method is a cornerstone of many statistical modeling applications that range from physics, chemistry, and biology to economics. This method is particularly suitable for sampling the thermal ...
    • Quantum‐Mechanical Study of Rotational and Vibrational Transitions in CO Induced by H Atoms 

      Balakrishnan, N.; Yan, M.; Dalgarno, A. (American Astronomical Society, 2002)
      We report rate coefficients for rotational and vibrational transitions in CO induced by H atoms using quantum-mechanical scattering calculations and the H-CO interaction potential of Keller et al. We use the infinite-order ...
    • Quarantine on the Line 

      Bonhomme, Edna (2021-07)
    • Quark and Gluon Jet Substructure 

      Gallicchio, Jason; Schwartz, Matthew D (Springer Science + Business Media, 2013)
      Distinguishing quark-initiated jets from gluon-initiated jets has the potential to significantly improve the reach of many beyond-the-standard model searches at the Large Hadron Collider and to provide additional tests of ...
    • Quark and Gluon Tagging at the LHC 

      Gallicchio, Jason; Schwartz, Matthew D (American Physical Society, 2011)
      Being able to distinguish light-quark jets from gluon jets on an event-by-event basis could significantly enhance the reach for many new physics searches at the Large Hadron Collider. Through an exhaustive search of existing ...
    • Quasar energy distributions. I - Soft X-ray spectra of quasars 

      Wilkes, Belinda Jane; Elvis, Martin S. (IOP Publishing, 1987)
      As the initial stage of a study of quasar energy distributions (QEDs), Einstein IPC spectra of 24 quasars are presented. These are combined with previously reported IPC spectra to form a sample of 33 quasars with well-determined ...
    • Quasar X-ray spectra revisited 

      Shastri, P.; Wilkes, Belinda Jane; Elvis, Martin S.; McDowell, Jonathan Christopher (IOP Publishing, 1993)
      A sample of 45 quasars observed by the IPC on the Einstein satellite is used to re-examine the relationship between the soft (0.2-3.5 keV) X-ray energy index and radio-loudness. We find that, (1) the tendency for radio-loud ...
    • Quasar X-Ray Spectra Revisited: Erratum 

      Shastri, P.; Wilkes, Belinda Jane; Elvis, Martin S.; McDowell, Jonathan Christopher (IOP Publishing, 1994)
      In the paper "Quasar X-Ray Spectra Revisited " by P. Shastri, B. J. Wilkes, M. Elvis, and J. McDowell (ApJ, 410,29 [1993]), there is an error in the flux density levels in Figures 4a and 4b. As a result of an error during ...
    • Quasars Are Not Light Bulbs: Testing Models of Quasar Lifetimes with the Observed Eddington Ratio Distribution 

      Hopkins, Philip F.; Hernquist, Lars (American Astronomical Society, 2009)
      We use the observed distribution of Eddington ratios as a function of supermassive black hole (BH) mass to constrain models of quasar/active galactic nucleus (AGN) lifetimes and light curves. Given the observed (well ...
    • Quasi-Experimental Evaluations of Pediatric Health Care: Clinical Practice Guidelines and Insurance Coverage 

      Chua, Kao-Ping (2015-05-12)
      The underlying theme of this dissertation is the effects of clinical and federal policy on health, utilization, and expenditures among children and young adults. In Chapter 1, I evaluate the clinical and economic benefits ...
    • Quasi-Experimental Health Policy Research: Evaluation of Universal Health Insurance and Methods for Comparative Effectiveness Research 

      Garabedian, Laura Faden (2013-10-08)
      This dissertation consists of two empirical papers and one methods paper. The first two papers use quasi-experimental methods to evaluate the impact of universal health insurance reform in Massachusetts (MA) and Thailand ...
    • Quasi-experiments to establish causal effects of HIV care and treatment and to improve the cascade of care 

      Bor, Jacob; Geldsetzer, Pascal; Venkataramani, Atheendar; Bärnighausen, Till (Lippincott Williams & Wilkins, 2015)
      Purpose of review Randomized, population-representative trials of clinical interventions are rare. Quasi-experiments have been used successfully to generate causal evidence on the cascade of HIV care in a broad range of ...