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Fluctuations In A Cosmology With A Spacelike Singularity And Their Gauge Theory Dual Description, Robert H. Brandenberger, Elisa G.M. Ferreira, Ian A. Morrison, Yi-Fu Cai, Sumit R. Das, Yi Wang 2016 McGill University

Fluctuations In A Cosmology With A Spacelike Singularity And Their Gauge Theory Dual Description, Robert H. Brandenberger, Elisa G.M. Ferreira, Ian A. Morrison, Yi-Fu Cai, Sumit R. Das, Yi Wang

Ian Morrison

We consider a time-dependent deformation of anti–de Sitter (AdS) space-time which contains a spacelike “singularity”—a spacelike region of high curvature. Making use of the AdS/CFT correspondence we can map the bulk dynamics onto the boundary. The boundary theory has a time dependent coupling constant which becomes small at times when the bulk space-time is highly curved. We investigate the propagation of small fluctuations of a test scalar field from early times before the bulk singularity to late times after the singularity. Under the assumption that the AdS/CFT correspondence extends to deformed AdS space-times, we can map ...


Rainich Conditions In (2+1)-Dimensional Gravity, Dionisios Krongos, Charles G. Torre 2016 Selected Works

Rainich Conditions In (2+1)-Dimensional Gravity, Dionisios Krongos, Charles G. Torre

Charles G. Torre

In (3 + 1) spacetime dimensions the Rainich conditions are a set of equations expressed solely in terms of the metric tensor which are equivalent to the Einstein-Maxwell equations for non-null electromagnetic fields. Here we provide the analogous conditions for (2 + 1)-dimensional gravity coupled to electromagnetism. Both the non-null and null cases are treated. The construction of these conditions is based upon reducing the problem to that of gravity coupled to a scalar field, which we have treated elsewhere. These conditions can be easily extended to other theories of (2 + 1)-dimensional gravity. For example, we apply the geometrization conditions ...


Fluctuations In A Cosmology With A Spacelike Singularity And Their Gauge Theory Dual Description, Robert H. Brandenberger, Elisa G.M. Ferreira, Ian A. Morrison, Yi-Fu Cai, Sumit R. Das, Yi Wang 2016 McGill University

Fluctuations In A Cosmology With A Spacelike Singularity And Their Gauge Theory Dual Description, Robert H. Brandenberger, Elisa G.M. Ferreira, Ian A. Morrison, Yi-Fu Cai, Sumit R. Das, Yi Wang

Physics

We consider a time-dependent deformation of anti–de Sitter (AdS) space-time which contains a spacelike “singularity”—a spacelike region of high curvature. Making use of the AdS/CFT correspondence we can map the bulk dynamics onto the boundary. The boundary theory has a time dependent coupling constant which becomes small at times when the bulk space-time is highly curved. We investigate the propagation of small fluctuations of a test scalar field from early times before the bulk singularity to late times after the singularity. Under the assumption that the AdS/CFT correspondence extends to deformed AdS space-times, we can map ...


Measurement And Modeling Of Cosmic Ray Exposure For Supercdms Dark Matter Detectors., Kameron McCall, John Orrell, Jared Yamaoka 2016 University of Houston - Main

Measurement And Modeling Of Cosmic Ray Exposure For Supercdms Dark Matter Detectors., Kameron Mccall, John Orrell, Jared Yamaoka

STAR (STEM Teacher and Researcher) Presentations

Dark matter is an unknown type of matter that composes roughly 27% of the observable universe and, as cosmological structure models suggest, the earth should be passing through a “dark halo” of this unknown matter present in the Milky Way galaxy. As we pass through this halo, the Super Cryogenic Dark Matter Search (SuperCDMS) experiment aims to directly detect dark -matter particles. Though many dark matter particle candidates exist, SuperCDMS focuses on the detection of particles called WIMPS (weakly interacting massive particles) as predicted by super-symmetric theories beyond the standard model. Due to the high-sensitivity of the germanium detectors employed ...


Some 2-Categorical Aspects In Physics, Arthur Parzygnat 2016 The Graduate Center, City University of New York

Some 2-Categorical Aspects In Physics, Arthur Parzygnat

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

2-categories provide a useful transition point between ordinary category theory and infinity-category theory where one can perform concrete computations for applications in physics and at the same time provide rigorous formalism for mathematical structures appearing in physics. We survey three such broad instances. First, we describe two-dimensional algebra as a means of constructing non-abelian parallel transport along surfaces which can be used to describe strings charged under non-abelian gauge groups in string theory. Second, we formalize the notion of convex and cone categories, provide a preliminary categorical definition of entropy, and exhibit several examples. Thirdly, we provide a universal description ...


Imaging Population Transfer In Atoms With Ultrafast Electron Pulses, Hua-Chieh Shao, Anthony F. Starace 2016 Purdue University

Imaging Population Transfer In Atoms With Ultrafast Electron Pulses, Hua-Chieh Shao, Anthony F. Starace

Anthony F. Starace Publications

We propose the use of ultrafast electron diffraction (UED) to image a controllable, laser-driven coherent electron population transfer in lithium atoms with currently available femtosecond electron pulses. Our simulations demonstrate the ability of ultrafast electrons to image such an electronic population transfer, thus validating UED as a direct means of investigating electron dynamics. Provided the incident electron pulses have sufficient temporal resolution, the diffraction images are shown to resolve also the relative phases of the target electronic wave functions.


Introduction To Classical Field Theory, Charles G. Torre 2016 Department of Physics, Utah State University

Introduction To Classical Field Theory, Charles G. Torre

All Complete Monographs

This is an introduction to classical field theory. Topics treated include: Klein-Gordon field, electromagnetic field, scalar electrodynamics, Dirac field, Yang-Mills field, gravitational field, Noether theorems relating symmetries and conservation laws, spontaneous symmetry breaking, Lagrangian and Hamiltonian formalisms.


A Study Of The Radiative Pion Capture Process As A Background To The Search For Muon To Electron Conversion With The Mu2e Experiment., Jacob Colston 2016 University of Louisville

A Study Of The Radiative Pion Capture Process As A Background To The Search For Muon To Electron Conversion With The Mu2e Experiment., Jacob Colston

Electronic Theses and Dissertations

This thesis will introduce radiative pion capture (RPC), a process which can produce a fake signal in a search for the coherent conversion of a muon to an electron in the presence of a nucleus. There will be a brief introduction to standard model (SM) physics, as well as some more in-depth discussion of the relevant high energy physics at the Mu2e experiment. We will discuss charged lepton flavor violation (CLFV), as well as Supersymmetry, which predicts CLFV at higher intensities than the SM prediction. A description of the RPC process follows, including the external and internal conversions in pion ...


Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses, Jean Marcel Ngoko Djiokap, Alexei V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace 2016 University of Nebraska-Lincoln

Multistart Spiral Electron Vortices In Ionization By Circularly Polarized Uv Pulses, Jean Marcel Ngoko Djiokap, Alexei V. Meremianin, N. L. Manakov, S. X. Hu, L. B. Madsen, Anthony F. Starace

Anthony F. Starace Publications

Multistart spiral vortex patterns are predicted for the electron momentum distributions in the polarization plane following ionization of the helium atom by two time-delayed circularly polarized ultrashort laser pulses. For two ultraviolet (UV) pulses having the same frequency (such that two photons are required for ionization), single-color two-photon interferometry with corotating or counter-rotating time-delayed pulses is found to lead respectively to zero-start or four-start spiral vortex patterns in the ionized electron momentum distributions in the polarization plane. In contrast, two-color one-photon plus two-photon interferometry with time-delayed corotating or counter-rotating UV pulses is found to lead respectively to one ...


New Classical Solutions In Supergravity, Zhibai Zhang 2016 Graduate Center, City University of New York

New Classical Solutions In Supergravity, Zhibai Zhang

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

In this Ph.D. thesis we construct three classes of new solutions to supergravity theories in various dimensions and study their properties. The first class is reduction ansatz of 10D and 11D supergravity on Ricci-flat and noncompact manifolds. These reductions are from a scaling limit of the famous spherical reductions, and can be solely supported by warp factors. The second class contains a large number of String/M theory solutions that have Lifshitz or Schrodinger scaling symmetry, obtained from marginally deforming the geometry of internal dimensions of previous solutions. We propose that these new solutions are dual to marginal deformations ...


Black Holes And Finite-Temperature Field Theory In Ads/Cft, Jackson Cross Olsen 2016 College of William and Mary

Black Holes And Finite-Temperature Field Theory In Ads/Cft, Jackson Cross Olsen

College of William & Mary Undergraduate Honors Theses

The Anti-de Sitter space/Conformal Field Theory (AdS/CFT) correspondence has motivated holographic models of physical phenomena at both zero and finite temperature. Zero-temperature results rely on one form of the correspondence, in which classical field theory calculations in a (usually modified) Anti-de Sitter space are said to be dual to calculations made for some quantum field theory at zero temperature. Finite-temperature calculations work similarly, except that the Anti-de Sitter space is taken to have a black hole horizon, and the correspondence is stated differently. In this work, we ask whether these two correspondences are in fact two distinct statements ...


Toward A Precision Measurement Of The Theta_13 Mixing Angle With The Double Chooz Detectors, Ben Thomas Rybolt 2016 University of Tennessee - Knoxville

Toward A Precision Measurement Of The Theta_13 Mixing Angle With The Double Chooz Detectors, Ben Thomas Rybolt

Doctoral Dissertations

Neutrinos are the most numerous and least understood particle in the universe. In the last few decades numerous experiments have been devoted to discovering their properties. The Double Chooz experiment was designed to make a precise measurement of θ13 [theta 13], the neutrino mixing parameter which describes flavor oscillations governing short baselines. To accomplish this measurement, two identical neutrino detectors have been deployed at a near and far baseline outside two commercial nuclear reactors. The neutrino flux and spectrum at the near and far detector sites will determine the disappearance of anti-neutrinos created inside the reactors.

I have contributed ...


Using Precise Measurements Of Muon G-2 To Constrain New Physics, Evan M. Heintz 2016 Otterbein University

Using Precise Measurements Of Muon G-2 To Constrain New Physics, Evan M. Heintz

Honors Thesis Projects

We study the contributions to the anomalous magnetic moment of the muon from theories beyond the Standard Model, specifically supersymmetry. Results found at Brookhaven National Laboratory in 2001 during the E821 experiment indicate that current theories may not fully account for all of the interactions between the muon and fundamental gauge bosons. We re-derive Dirac's famous result of g=2. We then reproduce the one loop contributions from electroweak theory to the anomalous magnetic moment of the muon. We then use these calculations as a template for theories that go beyond the Standard Model. We show illustrative results for ...


Sensitivity Determination In The Chips Neutrino Detector, Eve Adde Chase 2016 College of William and Mary

Sensitivity Determination In The Chips Neutrino Detector, Eve Adde Chase

College of William & Mary Undergraduate Honors Theses

Through neutrino detection, we strive to provide constraints on various neutrino properties such as $\delta_{CP}$ and mass hierarchy. Neutrinos are difficult to detect and require large neutrino detectors with appropriate conditions to determine $\delta_{CP}$. While several neutrino experiments strive to constrain $\delta_{CP}$, additional detectors are necessary to further constrain these parameters. We present a computational model to determine detector sensitivity towards measuring unknown oscillation properties. This model focused on the CHIPS neutrino detector, a low-cost experiment designed to test detector technologies while providing to the wealth of information on neutrino properties. Sensitivity constraints are presented for $\Delta ...


Cebaf Upgrade Bunch Length Measurements, Mahmoud Mohamad Ali Ahmad 2016 Old Dominion University

Cebaf Upgrade Bunch Length Measurements, Mahmoud Mohamad Ali Ahmad

Physics Theses & Dissertations

Many accelerators use short electron bunches and measuring the bunch length is important for efficient operations. CEBAF needs a suitable bunch length because bunches that are too long will result in beam interruption to the halls due to excessive energy spread and beam loss. In this work, bunch length is measured by invasive and non-invasive techniques at different beam energies. Two new measurement techniques have been commissioned; a harmonic cavity showed good results compared to expectations from simulation, and a real time interferometer is commissioned and first checkouts were performed. Three other techniques were used for measurements and comparison purposes ...


Universal Scaling Properties After Quantum Quenches, Damian Andres Galante 2016 The University of Western Ontario

Universal Scaling Properties After Quantum Quenches, Damian Andres Galante

Electronic Thesis and Dissertation Repository

In this Thesis, the problem of a quantum quench in quantum field theories is analyzed. This involves studying the real time evolution of observables in a theory that undergoes a change in one of its couplings. These quenches are then characterized by two parameters: $\delta \lambda$, the magnitude of the quench and most importantly, $\delta t$, the quench duration. In contrast to previous studies of abrupt quenches in the condensed matter theory community, we will be interested in smooth quenches with a finite $\delta t$.

Motivated by existing results in holographic theories, we studied the problem of a fast smooth ...


Atomic Photoionization Experiment By Harmonic-Generation Spectroscopy, M. V. Frolov, T. S. Sarantseva, N. L. Manakov, K. D. Fulfer, B. P. Wilson, J. Troß, X. Ren, Erwin D. Poliakoff, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace, C. A. Trallero-Herrero 2016 Voronezh State University, Russia

Atomic Photoionization Experiment By Harmonic-Generation Spectroscopy, M. V. Frolov, T. S. Sarantseva, N. L. Manakov, K. D. Fulfer, B. P. Wilson, J. Troß, X. Ren, Erwin D. Poliakoff, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace, C. A. Trallero-Herrero

Anthony F. Starace Publications

Measurements of the high-order-harmonic generation yield of the argon (Ar) atom driven by a strong elliptically polarized laser field are shown to completely determine the field-free differential photoionization cross section of Ar, i.e., the energy dependence of both the angle-integrated photoionization cross section and the angular distribution asymmetry parameter.


Control Of Threshold Enhancements In Harmonic Generation By Atoms In A Two-Color Laser Field With Orthogonal Polarizations, M. V. Frolov, N. L. Manakov, T. S. Sarantseva, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace 2016 Voronezh State University, Russia

Control Of Threshold Enhancements In Harmonic Generation By Atoms In A Two-Color Laser Field With Orthogonal Polarizations, M. V. Frolov, N. L. Manakov, T. S. Sarantseva, A. A. Silaev, N. V. Vvedenskii, Anthony F. Starace

Anthony F. Starace Publications

Threshold phenomena (or channel-closing effects) are analyzed in high-order harmonic generation (HHG) by atoms in a two-color laser field with orthogonal linearly polarized components of a fundamental field and its second harmonic. We show that the threshold behavior of HHG rates for the case of a weak second harmonic component is sensitive to the parity of a closing multiphoton ionization channel and the spatial symmetry of the initial bound state of the target atom, while for the case of comparable intensities of both components, suppression of threshold phenomena is observed as the relative phase between the components of a two-color ...


The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre 2016 Utah State University

The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre

Downloads

This is the entire DifferentialGeometry package, a zip file (DifferentialGeometry.zip) containing (1) a Maple Library file, DifferentialGeometryUSU.mla, (2) a Maple help file DifferentialGeometry.help. This is the latest version of the DifferentialGeometry software; it supersedes what is released with Maple. It has been tested on Maple versions 17, 18, 2015.

Installation instructions


Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert McNees, Robert Mann 2016 Loyola University Chicago

Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert Mcnees, Robert Mann

Robert A McNees IV

A variational formulation is given for a theory of gravity coupled to a massive vector in four dimensions, with Asymptotically Lifshitz boundary conditions on the fields. For theories with critical exponent z=2 we obtain a well-defined variational principle by explicitly constructing two actions with local boundary counterterms. As part of our analysis we obtain solutions of these theories on a neighborhood of spatial infinity, study the asymptotic symmetries, and consider different definitions of the boundary stress tensor and associated charges. A constraint on the boundary data for the fields figures prominently in one of our formulations, and in that ...


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