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Articles 1 - 30 of 415
Full-Text Articles in Cosmology, Relativity, and Gravity
Neutrino’S Non-Zero Electric Potential As An Origin Of Gravitation, Domain Structure And Expansion Of The Universe., Polievkt Perov
Neutrino’S Non-Zero Electric Potential As An Origin Of Gravitation, Domain Structure And Expansion Of The Universe., Polievkt Perov
College of Arts & Sciences Faculty Works
The axial electric potentials of neutrinos as neutral composite structures, while being very small at large distances, do not vanish, and the same can be said about the neutrino “asymmetric dipoles” (paired neutrinos of not the same kind). Depending on the orientation of the “asymmetric dipole”, its far-field electric potential in some direction can be positive or negative, interacting with other “dipoles” at that large distance attractively or repulsively depending on their mutual orientation. The mutual orientation of the dipoles locally (inside a galaxy) might be such that they are aligned and experience the attractive force toward the local center …
Conventions, Definitions, Identities, And Other Useful Formulae, Robert A. Mcnees Iv
Conventions, Definitions, Identities, And Other Useful Formulae, Robert A. Mcnees Iv
Physics: Faculty Publications and Other Works
As the name suggests, these notes contain a summary of important conventions, definitions, identities, and various formulas that I often refer to. They may prove useful for researchers working in General Relativity, Supergravity, String Theory, Cosmology, and related areas.
Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache
Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, Victor Christianto, T. Daniel Chandra, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
The present article was partly inspired by G. Pollack’s book, and also Dadoloff, Saxena & Jensen (2010). As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1, No. 2, 2022), for example, things and Beings can travel between Universes, intentionally or unintentionally [4]. In this short remark, we revisit and offer short remark to Neil Boyd’s ideas and trying to connect them with geometry of musical chords as presented by D. Tymoczko and others, then to Escherian staircase and then to Jacob’s ladder which seems to pointto possibility to interpret Jacob’s vision …
Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, Victor Christianto, T. Daniel Chandra, Florentin Smarandache
Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, Victor Christianto, T. Daniel Chandra, Florentin Smarandache
Branch Mathematics and Statistics Faculty and Staff Publications
As a senior physicist colleague and our friend, Robert N. Boyd, wrote in a journal (JCFA, Vol. 1,. 2, 2022), Our universe is but one page in a large book [4]. For example, things and Beings can travel between Universes, intentionally or unintentionally. In this short remark, we revisit and offer short remark to Neil’s ideas and trying to connect them with geometrization of musical chords as presented by D. Tymoczko and others, then to Escher staircase and then to Jacob’s ladder which seems to point to possibility to interpret Jacob’s vision as described in the ancient book of Genesis …
Mapping Galactic Acceleration With Pulsar Timing, Abigail Moran
Mapping Galactic Acceleration With Pulsar Timing, Abigail Moran
University Scholar Projects
We have conducted a cross match of objects in Gaia Early Data Release 3 and millisecond pulsars (MSPs) in the International Pulsar Timing Array’s Data Release 2 (IPTA DR2) to identify binary systems. Gaia has parallax measurements for these optical companions, which we combine with pulsar timing based parallax measurements to calculate new combined MSP distances. Through this crossmatch with IPTA DR2 we improved five distance measurements and found the first parallax measurement for one MSP.
Using this Gaia crossmatch method now with a well-timed subset of the Australia Telescope National Facility’s database, we found three new pulsar distances. We …
Eccentric Pairs: Analytic Gravitational Waves From Binary Black Holes In Elliptic Orbits, Dillon Buskirk, Maria Babiuc-Hamilton
Eccentric Pairs: Analytic Gravitational Waves From Binary Black Holes In Elliptic Orbits, Dillon Buskirk, Maria Babiuc-Hamilton
Physics Faculty Research
Gravitational waves (GW) from eccentric binaries have intricate signals encoding important features about the location, creation and evolution of the sources. Eccentricity shortens the merger time, making the emitted GW statistically predominant in the observed data once detectors will reach the required sensitivity. We present a novel implementation of fully analytical GW templates from eccentric binary black hole (BBH) mergers within the Wolfram Mathematica software. We increase the accuracy by identifying and minimizing the possible source of errors. We start with an overview of the physics involved in eccentric mergers, then assemble the strain for the inspiral by employing up …
Black Holes, Disk Structures, And Cosmological Implications In E-Dimensional Space, Subhash Kak, Menas C. Kafatos
Black Holes, Disk Structures, And Cosmological Implications In E-Dimensional Space, Subhash Kak, Menas C. Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
We examine a modern view of the universe that builds on achieved successes of quantum mechanics, general relativity, and information theory, bringing them together in integrated approach that is founded on the realization that space itself is e-dimensional. The global and local implications of noninteger dimensionality are examined, and how it may have increased from the value of zero to its current value is investigated. We find surprising aspects that tie to structures in the universe, black holes, and the role of observations.
Fermion-Induced Electroweak Symmetry Non-Restoration Via Temperature-Dependent Masses, Yu Hang Ng
Fermion-Induced Electroweak Symmetry Non-Restoration Via Temperature-Dependent Masses, Yu Hang Ng
Department of Physics and Astronomy: Dissertations, Theses, and Student Research
Standard Model (SM) and many extensions of SM predict that the electroweak (EW) symmetry was restored in the early universe when the temperature was around 160 GeV. However, recent studies showed that the interactions between some new scalars and SU(2)_L Higgs doublet(s) can cause the EW symmetry to remain broken at temperatures well above the EW scale in certain renormalizable extensions of SM. In this study, we found that new fermions from renormalizable models can also induce this EW symmetry non-restoration effect, provided that they have the appropriate temperature-dependent masses. These masses can arise naturally from the interactions between the …
Challenging Predictions Of Inflationary Models With Cmb Data, Richik Bhattacharya, Atanu Debnath, Esha Sajjanhar, Shravani Sardeshpande, Pablo Tenorio Hernández, José Ricardo Torres Heredia
Challenging Predictions Of Inflationary Models With Cmb Data, Richik Bhattacharya, Atanu Debnath, Esha Sajjanhar, Shravani Sardeshpande, Pablo Tenorio Hernández, José Ricardo Torres Heredia
2022 REYES Proceedings
Cosmic inflation offers the best known explanations for many of the observed features of the Universe, such as its flatness. An imprint of the qualities of this mechanism is left in the cosmic microwave background (CMB), which can be instrumental to confirm inflation. Unfortunately, there is a plethora of inflationary models, which are a priori in the same footing. It is conceivable that contrasting the predictions of the various models with the measured values of the parameters of CMB data and other cosmological observables shall allow one to single out the successful theory of inflation. In this work we provide …
Utilizing Post-Newtonian Expansion To Determine Parameters Of Compact Binary Black Hole Mergers, Jarrod E. Rudis
Utilizing Post-Newtonian Expansion To Determine Parameters Of Compact Binary Black Hole Mergers, Jarrod E. Rudis
Honors College
The process of determining parameters of black hole mergers requires complicated formulae like the Einstein Field Equations (EFEs) that can only be solved numerically with the help of supercomputers. This paper sought to explore an alternative method to prediction of parameters through the use of 1st order Post-Newtonian Expansion (PNE), which is a way of approximating solutions to the EFEs. Two binary- black hole mergers, GW170814 and GW170809 were analyzed with the use of 1st order PNE to obtain the chirp mass and radiated energy parameters. These parameters were then compared with the parameters obtained using numerical solutions to the …
Spin-Orbit Gravitational Locking - An Effective Potential Approach, Christopher Clouse, Andrea Ferroglia, Miguel C. N. Fiolhais
Spin-Orbit Gravitational Locking - An Effective Potential Approach, Christopher Clouse, Andrea Ferroglia, Miguel C. N. Fiolhais
Publications and Research
The objective of this paper is to study the tidally locked 3:2 spin–orbit resonance of Mercury around the Sun. In order to achieve this goal, the effective potential energy that determines the spinning motion of an ellipsoidal planet around its axis is considered. By studying the rotational potential energy of an ellipsoidal planet orbiting a spherical star on an elliptic orbit with fixed eccentricity and semi-major axis, it is shown that the system presents an infinite number of metastable equilibrium configurations. These states correspond to local minima of the rotational potential energy averaged over an orbit, where the ratio between …
The World As We Know It: Maps And Atlases From Special Collections, Archives And Special Collections, Luke Meagher
The World As We Know It: Maps And Atlases From Special Collections, Archives And Special Collections, Luke Meagher
Library Exhibits
Selections of maps and atlases from Sandor Teszler Library’s Special Collections are presented in this exhibit to show how, over time, cartographers have represented the world as we know it.
Venus Mountain Waves In The Upper Atmosphere Simulated By A Time-Invariant Linear Full-Wave Spectral Model, Michael P. Hickey, Richard L. Walterscheid, Thomas Navarro, Gerald Schubert
Venus Mountain Waves In The Upper Atmosphere Simulated By A Time-Invariant Linear Full-Wave Spectral Model, Michael P. Hickey, Richard L. Walterscheid, Thomas Navarro, Gerald Schubert
Publications
A 2-D spectral full-wave model is described that simulates the generation and propagation of mountain waves over idealized topography in Venus' atmosphere. Modeled temperature perturbations are compared with the Akatsuki observations. Lower atmosphere eddy diffusivity and stability play a major role in the upward propagation of gravity waves from their mountain sources. Two local times (LT) are considered. For LT = 11 h the waves are blocked by a critical level near 100 km altitude, while for LT = 16 h the waves propagate into the thermosphere. As a result of the small scale height in the Venus thermosphere, for …
The Meaning Of Dark, Light And Shadows: Inferences In Art, Materiality And Cultural Practices, Frank Prendergast
The Meaning Of Dark, Light And Shadows: Inferences In Art, Materiality And Cultural Practices, Frank Prendergast
Book/Book Chapter
Our visual awareness relies on light acting on the eye to perceive materiality and colour. Medieval thought wrestled to articulate and comprehend its nature. The notebooks of Leonardo Da Vinci, for example, included his descriptions to define light and make comparisons so as to differentiate between light and shadow. His focus was on the illumination of surfaces from the perspective of a painter, seeing shadows as ‘the diminution of light by the intervention of an opaque body’ and ‘the counterpart of luminous rays’. In his mind, a shadow ‘stood between light and darkness’, with darkness being ‘the absence of light’. …
Trapped Surfaces, Topology Of Black Holes, And The Positive Mass Theorem, Lan-Hsuan Huang, Dan A. Lee
Trapped Surfaces, Topology Of Black Holes, And The Positive Mass Theorem, Lan-Hsuan Huang, Dan A. Lee
Publications and Research
No abstract provided.
A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Charles G. Torre
A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Charles G. Torre
Research Vignettes
No abstract provided.
The Differentialgeometry Package, Ian M. Anderson, Charles G. Torre
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, (3) a Maple Library file, DGApplicatons.mla. This is the latest version of the DifferentialGeometry software; it supersedes what is released with Maple.
A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Ian M. Anderson, Charles G. Torre
A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Ian M. Anderson, Charles G. Torre
Publications
We find a new homogeneous solution to the Einstein-Maxwell equations with a cos- mological term. The spacetime manifold is R × S3. The spacetime metric admits a simply transitive isometry group G = R × SU(2) and is Petrov type I. The spacetime is geodesically complete and globally hyperbolic. The electromagnetic field is non- null and non-inheriting: it is only invariant with respect to the SU(2) subgroup and is time-dependent in a stationary reference frame.
What's New In Differentialgeometry Release Dg2022, Ian M. Anderson, Charles G. Torre
What's New In Differentialgeometry Release Dg2022, Ian M. Anderson, Charles G. Torre
Tutorials on... in 1 hour or less
This Maple worksheet demonstrates the salient new features and functionalities of the 2022 release of the DifferentialGeometry software package.
Perturbative Unitarity And Nec Violation In Genesis Cosmology, Yong Cai, Ji Xu, Shuai Zhao, Siyi Zhou
Perturbative Unitarity And Nec Violation In Genesis Cosmology, Yong Cai, Ji Xu, Shuai Zhao, Siyi Zhou
Physics Faculty Publications
Explorations of the violation of null energy condition (NEC) in cosmology could enrich our understanding of the very early universe and the related gravity theories. Although a fully stable NEC violation can be realized in the “beyond Horndeski” theory, it remains an open question whether a violation of the NEC is allowed by some fundamental properties of UV-complete theories or the consistency requirements of effective field theory (EFT). We investigate the tree-level perturbative unitarity for stable NEC violations in the contexts of both Galileon and “beyond Horndeski” genesis cosmology, in which the universe is asymptotically Minkowskian in the past. We …
𝒯, 𝒫-Odd Effects In The Luoh⁺ Cation, Daniel E. Maison, Leonid V. Skripnikov, Gleb Penyazkov, Matt Grau, Alexander N. Petrov
𝒯, 𝒫-Odd Effects In The Luoh⁺ Cation, Daniel E. Maison, Leonid V. Skripnikov, Gleb Penyazkov, Matt Grau, Alexander N. Petrov
Physics Faculty Publications
The LuOH+ cation is a promising system to search for manifestations of time reversal and spatial parity violation effects. Such effects in LuOH+ induced by the electron electric dipole moment eEDM and the scalar-pseudoscalar interaction of the nucleus with electrons, characterized by ks constant, in LuOH+ are studied. The enhancement factors, polarization in the external electric field, hyperfine interaction, and rovibrational structure are calculated. The study is required for the experiment preparation and extraction of the eEDM and ks values from experimental data.
Superluminal Propagation On A Moving Braneworld, Brian Greene, Daniel Kabat, Janna Levin, Arjun S. Menon
Superluminal Propagation On A Moving Braneworld, Brian Greene, Daniel Kabat, Janna Levin, Arjun S. Menon
Publications and Research
We consider a braneworld scenario in the simplest setting, M4 × S1, with a four-dimensional (4D) Minkowski metric induced on the brane, and establish the possibility of superluminal propagation. If the brane is at rest, the 4D Lorentz symmetry of the brane is exact, but if the brane is in motion, it is broken globally by the compactification. By measuring bulk fields, an observer on the brane sees a slice through a higher-dimensional field profile, which carries an imprint of the extra dimensions even when the brane is at rest. If the brane is in motion, we …
Newgrange Skyscape In Stellarium, Frank Prendergast
Newgrange Skyscape In Stellarium, Frank Prendergast
Articles
Newgrange Skyscape in Stellarium is a new customised landscape planetarium model giving the user the unique ability to interrogate the dynamic sky above the Boyne Valley on any date of interest during the hours of daylight or darkness. Archaeological, astronomical and topographical points of interest are labelled in the model and visible even during the hours of darkness. These are summarily described in a short gazetteer appended at the end of the instruction document to encourage further exploration of the wonderful heritage found in the Boyne Valley and beyond.
Watch on Youtube: https://www.youtube.com/watch?app=desktop&v=aGPsVGBXkY4
Watch on Vimeo: https://vimeo.com/493351576
Impact Of Weak Gravitational Force In Sri Lanka, Periyandy Thunendran
Impact Of Weak Gravitational Force In Sri Lanka, Periyandy Thunendran
English Language Institute
Gravity studies explain about the sub surface features and shape of the earth, and show gravitational force is weak in the Sri Lanka region, which has positive and negative impacts. This poster argues further studies on gravity are needed to revise the global gravitational model of the region.
Population Properties Of Compact Objects From The Second Ligo-Virgo Gravitational-Wave Transient Catalog, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, A. Adams, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, Tiffany Z. Summerscales
Population Properties Of Compact Objects From The Second Ligo-Virgo Gravitational-Wave Transient Catalog, R. Abbott, T. D. Abbott, S. Abraham, F. Acernese, K. Ackley, A. Adams, C. Adams, R. X. Adhikari, V. B. Adya, C. Affeldt, M. Agathos, K. Agatsuma, N. Aggarwal, O. D. D. Aguiar, L. Aiello, A. Ain, P. Ajith, G. Allen, A. Allocca, Tiffany Z. Summerscales
Faculty Publications
We report on the population of 47 compact binary mergers detected with a false-alarm rate of (BBH) population not discernible until now. First, the primary mass spectrum contains structure beyond a power law with a sharp high-mass cutoff; it is more consistent with a broken power law with a break at 39.7-+9.120.3 M? or a power law with a Gaussian feature peaking at 33.1-+5.64.0 M? (90% credible interval). While the primary mass distribution must extend to ~65 M? or beyond, only 2.9-+1.73.5% of systems have primary masses greater than 45 M?. Second, we find that a fraction of BBH systems …
Experimental Constraint On Axionlike Particles Over Seven Orders Of Magnitude In Mass, Tanya S. Roussy, Daniel A. Palken, William B. Cairncross, Benjamin M. Brubaker, Daniel N. Gresh, Matt Grau, Kevin C. Cossel, Kia Boon Ng, Yuval Shagam, Yan Zhou, Victor V. Flambaum, Konrad W. Lehnert, Jun Ye, Eric A. Cornell
Experimental Constraint On Axionlike Particles Over Seven Orders Of Magnitude In Mass, Tanya S. Roussy, Daniel A. Palken, William B. Cairncross, Benjamin M. Brubaker, Daniel N. Gresh, Matt Grau, Kevin C. Cossel, Kia Boon Ng, Yuval Shagam, Yan Zhou, Victor V. Flambaum, Konrad W. Lehnert, Jun Ye, Eric A. Cornell
Physics & Astronomy Faculty Research
We use our recent electric dipole moment (EDM) measurement data to constrain the possibility that the HfF+ EDM oscillates in time due to interactions with candidate dark matter axionlike particles (ALPs). We employ a Bayesian analysis method which accounts for both the look-elsewhere effect and the uncertainties associated with stochastic density fluctuations in the ALP field. We find no evidence of an oscillating EDM over a range spanning from 27 nHz to 400 mHz, and we use this result to constrain the ALP-gluon coupling over the mass range 10-22-10-15 eV. This is the first laboratory constraint on the ALP-gluon coupling …
Concentrated Lunar Resources: Imminent Implications For Governance And Justice, Martin Elvis, Alanna Krolikowski, Tony Milligan
Concentrated Lunar Resources: Imminent Implications For Governance And Justice, Martin Elvis, Alanna Krolikowski, Tony Milligan
History and Political Science Faculty Research & Creative Works
Numerous missions planned for the next decade are likely to target a handful of small sites of interest on the Moon's surface, creating risks of crowding and interference at these locations. The Moon presents finite and scarce areas with rare topography or concentrations of resources of special value. Locations of interest to science, notably for astronomy, include the Peaks of Eternal Light, the coldest of the cold traps and smooth areas on the far side. Regions richest in physical resources could also be uniquely suited to settlement and commerce. Such sites of interest are both few and small. Typically, there …
The Causal Topology Of Neutral 4-Manifolds With Null Boundary, Nikos Georgiou, Brendan Guilfoyle
The Causal Topology Of Neutral 4-Manifolds With Null Boundary, Nikos Georgiou, Brendan Guilfoyle
Publications
This paper considers aspects of 4-manifold topology from the point of view of the null cone of a neutral metric, a point of view we call neutral causal topology. In particular, we construct and investigate neutral 4-manifolds with null boundaries that arise from canonical 3- and 4-dimensional settings. A null hypersurface is foliated by its normal and, in the neutral case, inherits a pair of totally null planes at each point. This paper focuses on these plane bundles in a number of classical settings The first construction is the conformal compactification of flat neutral 4- space into the 4-ball. The …
Tidal Locking And The Gravitational Fold Catastrophe, Andrea Ferroglia, Miguel C. N. Fiolhais
Tidal Locking And The Gravitational Fold Catastrophe, Andrea Ferroglia, Miguel C. N. Fiolhais
Publications and Research
The purpose of this work is to study the phenomenon of tidal locking in a pedagogical framework by analyzing the effective gravitational potential of a two-body system with two spinning objects. It is shown that the effective potential of such a system is an example of a fold catastrophe. In fact, the existence of a local minimum and saddle point, corresponding to tidally locked circular orbits, is regulated by a single dimensionless control parameter that depends on the properties of the two bodies and on the total angular momentum of the system. The method described in this work results in …
Mars 2020: A Step Closer To The Red Planet, Kevin Ng, Matthew Khargie, Omadevi Singh, Sashi Singh, Nazrul I. Khandaker, Rajendra Persaud
Mars 2020: A Step Closer To The Red Planet, Kevin Ng, Matthew Khargie, Omadevi Singh, Sashi Singh, Nazrul I. Khandaker, Rajendra Persaud
Publications and Research
This research paper primarily focuses on the NASA Mars 2020 mission, but will also revisit and discuss past rover missions. As the Mars 2020 mission is ongoing, some information will be updated accordingly. For decades, humans have dreamed of the colonization of Mars for many reasons, such as some similarities shared by Earth and Mars or the close proximity to our planet. In fact, dozens of films, books, and articles have been written, especially in the past 2 decades, about the possibility. As technology advances, we develop newer equipment to hopefully make this possibility into a reality. Of course, placing …