The Riemann Curvature Tensor, Its Invariants, And Their Use In The Classification Of Spacetimes,
2015
Utah State University
The Riemann Curvature Tensor, Its Invariants, And Their Use In The Classification Of Spacetimes, Jesse Hicks
Presentations and Publications
The equivalence problem in general relativity is to determine whether two solutions of the Einstein field equations are isometric. Petrov has given a classification of metrics according to their isometry algebras. This talk discusses the use of the Petrov classification scheme, together with the use of scalar curvature invariants, to address the equivalence problem. These are the slides for a presentation at the Mathematics Association of America Spring 2015 conference at Brigham Young University.
Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields,
2015
Utah State University
Geometrization Conditions For Perfect Fluids, Scalar Fields, And Electromagnetic Fields, Charles G. Torre, Dionisios Krongos
Presentations and Publications
Rainich-type conditions giving a spacetime “geometrization” of matter fields in general relativity are reviewed and extended. Three types of matter are considered: perfect fluids, scalar fields, and elec- tromagnetic fields. Necessary and sufficient conditions on a spacetime metric for it to be part of a perfect fluid solution of the Einstein equa- tions are given. Formulas for constructing the fluid from the metric are obtained. All fluid results hold for any spacetime dimension. Ge- ometric conditions on a metric which are necessary and sufficient for it to define a solution of the Einstein-scalar field equations and for- mulas for constructing …
What Do We Know About Lorentz Symmetry?,
2015
Embry-Riddle Aeronautical University
What Do We Know About Lorentz Symmetry?, Q. G. Bailey
Publications
Precision tests of Lorentz symmetry have become increasingly of interest to the broader gravitational and high-energy physics communities. In this talk, recent work on violations of local Lorentz invariance in gravity is discussed, including recent analysis constraining Lorentz violation in a variety of gravitational tests. The arena of short-range tests of gravity is highlighted, demonstrating that such tests are sensitive to a broad class of unexplored signals that depend on sidereal time and the geometry of the experiment.
Short-Range Gravity And Lorentz Violation,
2015
Embry-Riddle Aeronautical University
Short-Range Gravity And Lorentz Violation, Quentin G. Bailey, V. Alan Kostelecký, Rui Xu
Publications
Comparatively few searches have been performed for violations of local Lorentz invariance in the pure-gravity sector. We show that tests of short-range gravity are sensitive to a broad class of unconstrained and novel signals that depend on the experimental geometry and on sidereal time.
Evidence Of Attenuation Of Vhe Blazar Spectra By Extragalactic Background Light,
2015
California Polytechnic State University - San Luis Obispo
Evidence Of Attenuation Of Vhe Blazar Spectra By Extragalactic Background Light, Cameron Allen
Physics
The spectrum of two blazar objects, 1ES 1959+650 and 1ES 2344+514, are analyzed for evidence of interactions with the Extragalactic Background Light (EBL), using combined data from the Very Energetic Radiation Imaging Telescope Array System and the Fermi Gamma-ray Space Telescope, By analyzing the distinct curvature across the combined spectrum, we infer that the very-high energy (VHE) gamma-rays must be attenuated by interactions with the EBL. We also find that the measured 1ES 1959+650 spectrum is sensitive to the intrinsic blazar model, with a preference for a power-law with an exponential cutoff (EPWL). The measured curvature is a combination of …
Unmatter Plasma, Relativistic Oblique-Length Contraction Factor, Neutrosophic Diagram And Neutrosophic Degree Of Paradoxicity: Articles And Notes,
2015
University of New Mexico
Unmatter Plasma, Relativistic Oblique-Length Contraction Factor, Neutrosophic Diagram And Neutrosophic Degree Of Paradoxicity: Articles And Notes, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
This book has four parts. In the first part, we collected five recent papers, published before in Progress in Physics, but reviewed. In the first paper, we approach a novel form of plasma, Unmatter Plasma. The electron-positron beam plasma was generated in the laboratory in the beginning of 2015. This experimental fact shows that unmatter, a new form of matter that is formed by matter and antimatter bind together (mathematically predicted a decade ago) really exists. That is the electron-positron plasma experiment of 2015 is the experimentum crucis verifying the mathematically predicted unmatter. In the second paper, we generalize the …
Quantum Tests Of The Einstein Equivalence Principle With The Ste-Quest Space Mission,
2015
University of South Carolina
Quantum Tests Of The Einstein Equivalence Principle With The Ste-Quest Space Mission, Brett Altschul, Quentin G. Bailey, Luc Blanchet, Kai Bongs, Philippe Bouyer, Luigi Cacciapuoti, Et Al.
Publications
We present in detail the scientific objectives in fundamental physics of the Space–Time Explorer and QUantum Equivalence Space Test (STE–QUEST) space mission. STE–QUEST was pre-selected by the European Space Agency together with four other missions for the cosmic vision M3 launch opportunity planned around 2024. It carries out tests of different aspects of the Einstein Equivalence Principle using atomic clocks, matter wave interferometry and long distance time/frequency links, providing fascinating science at the interface between quantum mechanics and gravitation that cannot be achieved, at that level of precision, in ground experiments. We especially emphasize the specific strong interest of performing …
Rainich-Type Conditions For Perfect Fluid Spacetimes,
2014
Utah State University
Rainich-Type Conditions For Perfect Fluid Spacetimes, Dionisios Krongos, Charles G. Torre
Research Vignettes
In this worksheet we describe and illustrate a relatively simple set of new Rainich-type conditions on an n-dimensional spacetime which are necessary and sufficient for it to define a perfect fluid solution of the Einstein field equations. Procedures are provided which implement these Rainich-type conditions and which reconstruct the perfect fluid from the metric. These results provide an example of the idea of geometrization of matter fields in general relativity, which is a purely geometrical characterization of matter fields via the Einstein field equations.
Detection Of Gravitational Wave Signals From Ns-Ns Inspirals In Presence Of Non-Stationary Noise,
2014
University of Texas at Brownsville
Detection Of Gravitational Wave Signals From Ns-Ns Inspirals In Presence Of Non-Stationary Noise, Wenhui Wang
Theses and Dissertations - UTB/UTPA
Gravitational Wave (GW) detection is an important and inspiring project. Once detected, it will open a new window to understand the universe. The laser interferometer GW detectors, specially LIGO, is the most sensitive detectors at the moment, which can detect GW signal as weak as 10−21. Chirp signal generated by neutron star binaries is a well modeled waveform. One goal of LIGO is to study chirp signal detection. In this field, matched filtering is a widely used method. But since LIGO noise is non-stationary, which will weaken the efficiency of general matched filtering. In this work, a modified matched filtering …
Pulsar J0453+1559, The 10th Double Neutron Star System In The Universe,
2014
University of Texas at Brownsville
Pulsar J0453+1559, The 10th Double Neutron Star System In The Universe, Jose Guadalupe Martinez
Theses and Dissertations - UTB/UTPA
Pulsars are neutron stars that spin rapidly, are highly magnetized, and they emit beams of electromagnetic radiation like a lighthouse out in space. These beams of radiation are only observed when the beams face towards Earth and can be measured by a radio telescope. Pulsar studies have an abundance of scientific implementations in solid state physics, general relativity, galactic astronomy, astronomy, planetary physics and have even opened windows in cosmology. This thesis reports the results of a study of pulsar (PSR) J0453+1559, a new binary pulsar discovered in the Arecibo All-Sky 327 MegaHertz Drift Pulsar Survey. The recorded observations of …
Can We Use The Nasa Gamma-Ray Burst Satellites, Fermi And Swift, To Aid The Search For The First Gravitational Wave Detection?,
2014
University of Alabama in Huntsville
Can We Use The Nasa Gamma-Ray Burst Satellites, Fermi And Swift, To Aid The Search For The First Gravitational Wave Detection?, E Burns
Von Braun Symposium Student Posters
No abstract provided.
Instability And Particle Acceleration In Relativistic Jets,
2014
University of Alabama in Huntsville
Instability And Particle Acceleration In Relativistic Jets, Qiana Hunt, Kyle Rettke
Von Braun Symposium Student Posters
No abstract provided.
Constraints On Very High Energy Emission From Grb 130427a,
2014
Department of Physical Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland
Constraints On Very High Energy Emission From Grb 130427a, P. T. Reynolds, Et Al
Physical Sciences Publications
Prompt emission from the very fluent and nearby (z = 0.34) gamma-ray burst GRB 130427A was detected by several orbiting telescopes and by ground-based, wide-field-of-view optical transient monitors. Apart from the intensity and proximity of this GRB, it is exceptional due to the extremely long-lived high-energy (100 MeV to 100 GeV) gamma-ray emission, which was detected by the Large Area Telescope on the Fermi Gamma-Ray Space Telescope for ~70 ks after the initial burst. The persistent, hard-spectrum, high-energy emission suggests that the highest-energy gamma rays may have been produced via synchrotron self-Compton processes though there is also evidence that …
Revised Age For Cm Draconis And Wd 1633+ 572-Toward A Resolution Of Model-Observation Radius Discrepancies,
2014
Uppsala University
Revised Age For Cm Draconis And Wd 1633+ 572-Toward A Resolution Of Model-Observation Radius Discrepancies, Gregory A. Feiden, Brian Chaboyer
Dartmouth Scholarship
We report an age revision for the low-mass detached eclipsing binary CM Draconis and its common proper motion companion, WD 1633+572. An age of 8.5 +/- 3.5 Gyr is found by combining an age estimate for the lifetime of WD 1633+572 and an estimate from galactic space motions. The revised age is greater than a factor of two older than previous estimates. Our results provide consistency between the white dwarf age and the system's galactic kinematics, which reveal the system is a highly probable mem
Dark Energy Scaling From Dark Matter To Acceleration,
2014
Dartmouth College
Dark Energy Scaling From Dark Matter To Acceleration, Jannis Bielefeld, Robert R. Caldwell, Eric Linder
Dartmouth Scholarship
The dark sector of the Universe need not be completely separable into distinct dark matter and dark energy components. We consider a model of early dark energy in which the dark energy mimics a dark matter component in both evolution and perturbations at early times. Barotropic aether dark energy scales as a fixed fraction, possibly greater than one, of the dark matter density and has vanishing sound speed at early times before undergoing a transition. This gives signatures not only in cosmic expansion but in sound speed and inhomogeneities, and in number of effective neutrino species. Model parameters describe the …
Measuring Noble Gases In Coma Samples From Comet Wild 2,
2014
Minnesota State University, Mankato
Measuring Noble Gases In Coma Samples From Comet Wild 2, Jacob Simones
Journal of Undergraduate Research at Minnesota State University, Mankato
Since comets originated during the formation of the solar system, the processes of solar system formation can be better understood through compositional analysis of cometary material. A low density, silicon-based substance called aerogel was used by NASA’s Stardust spacecraft to collect coma samples from comet Wild 2. Aerogel not from the spacecraft (“non-flight”) was investigated to determine the possibility of measuring noble gases in Stardust samples. Gas evolved from heated, non-flight aerogel was measured initially using a residual gas analyzer, then a high-sensitivity massspectrometer. Levels of helium and neon isotopes observed from both instruments were sufficiently low that noble gases …
Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches,
2014
Purdue University
Characterizing New Calibration Sources In Liquid Xenon Dark Matter Searches, Evan P. Bray, Rafael Lang, Sean Macmullin
The Summer Undergraduate Research Fellowship (SURF) Symposium
In order to use the XENON1T liquid xenon detector as a means for detecting dark matter, the response to nuclear and electronic recoils must be well calibrated. Electronic-recoil calibration of XENON1T will be done by using the noble gas radon-220 that emanates from a custom thorium-228 source to observe the electron recoils that its daughter elements induce in liquid xenon. A silicon PIN diode was constructed to ensure that the Th228 source does not contaminate the system with the long-lived isotopes Th228 (T1/2 of 1.9 y) or Radium-224 (T1/2 of 3.6 d). The PIN diode was fixed in a custom …
Search For Higgs Shifts In White Dwarfs,
2014
University of Padua
Search For Higgs Shifts In White Dwarfs, Roberto Onofrio, Gary A. Wegner
Dartmouth Scholarship
We report on a search for differential shifts between electronic and vibronic transitions in carbon-rich white dwarfs BPM 27606 and Procyon B. The absence of differential shifts within the spectral resolution and taking into account systematic effects such as space motion and pressure shifts allows us to set the first upper bound of astrophysical origin on the coupling between the Higgs field and the Kreschmann curvature invariant. Our analysis provides the basis for a more general methodology to derive bounds to the coupling of long-range scalar fields to curvature invariants in an astrophysical setting complementary to the ones available from …
Laser Frequency Stabilization For Lisa,
2014
California Polytechnic State University - San Luis Obispo
Laser Frequency Stabilization For Lisa, Andrew B. Parker, Andrew J. Sutton, Glenn De Vine
STAR Program Research Presentations
This research focuses on laser ranging developments for LISA (Laser Interferometer Space Antenna), a planned NASA-ESA gravitational wave detector in space. LISA will utilize precision laser interferometry to track the changes in separation between three satellites orbiting 5 million kilometers apart. Specifically, our goal is to investigate options for laser frequency stabilization. Previous research has shown that an optical cavity system can meet LISA's stability requirements, but these units are large and heavy, adding cost to the implementation. A heterodyne Mach-Zehnder interferometer could be integrated onto LISA’s existing optical bench, greatly reducing the weight, provided the interferometer meets the stability …
Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory,
2014
California State University - Long Beach
Environmental Testing Of Lasers For Jpl's Cold Atom Laboratory, Carey L. Baxter
STAR Program Research Presentations
NASA’s Cold Atom Lab (CAL) is a multi-user facility designed to study ultra-cold quantum gases in the microgravity environment of the International Space Station (ISS). One of the main goals of CAL is to explore the unknown territory of extremely low temperatures—possibly as low as the picokelvin range!—where new and fascinating quantum phenomena can be observed. At such temperatures matter stops behaving as particles and instead becomes macroscopic matter waves. CAL will be remotely controlled to perform a multitude of experiments and is scheduled to launch in 2016. In order to anticipate problems that might occur during and post-launch, including …
