Browsing by FAS Department "Physics"
Now showing items 41-60 of 2246
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Anomalies on orbifolds
(Elsevier BV, 2001)We discuss the form of the chiral anomaly on an S 1/Z2 orbifold with chiral boundary conditions. We find that the 4-divergence of the higher-dimensional current evaluated at a given point in the extra dimension is proportional ... -
Anomalous Expansion of Attractively Interacting Fermionic Atoms in an Optical Lattice
(American Association for the Advancement of Science, 2010)Strong correlations can dramatically modify the thermodynamics of a quantum many-particle system. Especially intriguing behaviour can appear when the system adiabatically enters a strongly correlated regime, for the interplay ... -
Another odd thing about unparticle physics
(Elsevier BV, 2007)The peculiar propagator of scale invariant unparticles has phases that produce unusual patterns of interference with standard model processes. We illustrate some of these effects in e +e − → µ +µ −. -
Anti-Brownian Traps for Studies on Single Molecules
(Elsevier BV, 2010)Until recently, Brownian motion was seen as an immutable feature of small particles in room-temperature liquids. Molecules, viruses, organelles, and small cells jiggle incessantly due to countless collisions with thermally ... -
Anti-Reflection Coating for Nitrogen-Vacancy Optical Measurements in Diamond
(American Institute of Physics (AIP), 2012)We realize anti-reflection (AR) coatings for optical excitation and fluorescence measurements of nitrogen-vacancy (NV) color centers in bulk diamond by depositing quarter-wavelength thick silica layers on the diamondsurface. ... -
Antiferromagnetic noise correlations in optical lattices
(American Physical Society (APS), 2009)We analyze how noise correlations probed by time-of-flight experiments reveal antiferromagnetic (AF) correlations of fermionic atoms in two-dimensional and three-dimensional optical lattices. Combining analytical and quantum ... -
Antiferromagnetism in Metals: From the Cuprate Superconductors to the Heavy Fermion Materials
(IOP Publishing, 2012)The critical theory of the onset of antiferromagnetism in metals, with concomitant Fermi surface reconstruction, has recently been shown to be strongly coupled in two spatial dimensions. The onset of unconventional ... -
Antiretroviral dynamics determines HIV evolution and predicts therapy outcome
(Nature Publishing Group, 2012)Despite the high inhibition of viral replication achieved by current anti-HIV drugs, many patients fail treatment, often with emergence of drug-resistant virus. Clinical observations show that the relationship between ... -
Anyonic Interferometry and Protected Memories in Atomic Spin Lattices
(Nature Publishing Group, 2008)Strongly correlated quantum systems can exhibit exotic behavior called topological order which is characterized by non-local correlations that depend on the system topology. Such systems can exhibit remarkable phenomena ... -
Aperiodic Stepwise Growth Model for the Velocity and Orientation Dependence of Solute Trapping
(Materials Research Society, 1987)An atomistic model for the dependence on interface orientation and velocity v of the solute partition coefficient <i>k</i> during rapid solidification is developed in detail. Starting with a simple stepwise growth model, ... -
Apparatus and Methods for a New Measurement of the Electron and Positron Magnetic Moments
(2018-01-05)This thesis presents contributions to two precision measurement experiments: electron and positron $g/2$, and ATRAP antihydrogen spectroscopy. The magnetic moment of the electron in Bohr magnetons, $g/2$, is the most ... -
Applications of Many Body Dynamics of Solid State Systems to Quantum Metrology and Computation
(2013-03-18)This thesis describes aspects of dynamics of solid state systems which are relevant to quantum metrology and computation. It may be divided into three research directions (parts). For the first part, a new method to enhance ... -
Arsenic atom location on passivated silicon (111) surfaces
(American Physical Society (APS), 1987)The position of As atoms on a clean Si(111) surface has been determined with x-ray standing waves in ultrahigh vacuum. The As atoms occupy exclusively the top half of the silicon (111) double plane and lie at 0.17 Å above ... -
Aspects of Symmetry in Asymptotically Flat Spacetimes
(2018-05-11)We explore the nature and implications of a variety of asymptotic symmetry groups associated to gauge theory and quantum gravity in asymptotically flat spacetimes. We re-express Weinberg's soft graviton theorem as a Ward ... -
Aspects of Symmetry in de Sitter Space
(2014-06-06)We study various aspects of symmetry in four-dimensional de Sitter space (dS$_4$). -
An astro-comb calibrated solar telescope to search for the radial velocity signature of Venus
(2016)We recently demonstrated sub-m/s sensitivity in measuring the radial velocity (RV) between the Earth and Sun using a simple solar telescope feeding the HARPS-N spectrograph at the Italian National Telescope, which is ... -
Asymmetric Mutualism in Two- and Three-Dimensional Range Expansions
(American Physical Society, 2014)Genetic drift at the frontiers of two-dimensional range expansions of microorganisms can frustrate local cooperation between different genetic variants, demixing the population into distinct sectors. In a biological context, ... -
Asymptotic Symmetries and Charges in De Sitter Space
(Institute of Physics Publishing, 2011)The asymptotic symmetry group (ASG) at future null infinity \((I^+)\) of four-dimensional de Sitter spacetimes is defined and shown to be given by the group of three-dimensional diffeomorphisms acting on \(I^+\). Finite ... -
Asymptotic Symmetries in Four-Dimensional Gauge and Gravity Theories
(2017-05-11)Recent developments have uncovered a deep relationship between soft theorems in quantum field theories and asymptotic symmetries. We investigate five explicit examples wherein these connections are studied and verified. ... -
Asymptotic symmetries of Yang-Mills theory
(Springer Science + Business Media, 2014)Asymptotic symmetries at future null infinity (I +) of Minkowski space for electrodynamics with massless charged fields, as well as non-Abelian gauge theories with gauge group G, are considered at the semiclassical level. ...