Synchronicity: An Analysis Of Einstein's Halfway Rule, 2024 Wayne State University

#### Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova

*Rushton Journal of Undergraduate Humanities Research*

For the modern world to function, Global Positioning System satellites must synchronize to clocks on Earth. This paper examines a concept that underlies GPS systems, namely Albert Einstein’s halfway rule—the idea that a line of simultaneity exists between two events in different systems. This essay discusses how Einstein used conventionalist methods to establish ½ as a constant value for *σ* to take advantage of the property of symmetry.

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part I: Theoretical Underpinning, 2023 University of New Mexico

#### 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 …

Godel, Escherian Staircase And Possibility Of Quantum Wormhole With Liquid Crystalline Phase Of Iced-Water - Part Ii: Experiment Description, 2023 University of New Mexico

#### 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 …

Tests Of General Relativity Through Searches For Lorentz And Cpt Symmetry Breaking, 2023 Embry-Riddle Aeronautical University

#### Tests Of General Relativity Through Searches For Lorentz And Cpt Symmetry Breaking, Kellie Ault

*Doctoral Dissertations and Master's Theses*

An effective field theory framework, the Standard Model Extension (SME), provides an agnostic, systematic test of General Relativity (GR) and its founding spacetime symmetries, Lorentz and CPT symmetry. Violating these symmetries may provide clues toward unifying the physics of the General Relativity and the Standard Model of particle physics. Part of this work involves the merge of theory, data analysis and experiments with gravitational wave (GW) signals from LIGO/Virgo/KAGRA (LVK) detectors. A modified dispersion relation derived from the SME of GWs is implemented into the LIGO Scientific Collaboration Algorithm Library Suite (LALSuite), where a joint Bayesian inference of the source …

Cosmic Diffuse Neutrino And Gamma-Ray Backgrounds In The Mev Regime, 2023 Clemson University

#### Cosmic Diffuse Neutrino And Gamma-Ray Backgrounds In The Mev Regime, Ilukpitiye Samalka Anandagoda

*All Dissertations*

Cosmic Multi-Messenger backgrounds include relic diffuse components created in the early Universe and contributions from individual sources. In this dissertation, I present the work done in Anandagoda (2019); Anandagoda et al. (2020, 2023) where type Ia (SNe Ia) and core-collapse supernovae (CCSNe) contributions to the diffuse neutrino and gamma-ray backgrounds in the MeV regime are studied. These backgrounds are referred to as DSNB and DSGB respectively. Based on this work, the diffuse SN Ia background is ~10^{6} times lower (for electron antineutrinos) than the CCSN background making it negligible. The predicted DSNB electron antineutrino flux at earth in the …

Simulating The Eccentricity Evolution Of Accreting Equal-Mass Binaries: Numerical Sensitivity To The Computational Domain Size And Grid Resolution, 2023 Clemson University

#### Simulating The Eccentricity Evolution Of Accreting Equal-Mass Binaries: Numerical Sensitivity To The Computational Domain Size And Grid Resolution, Zhongtian Hu

*All Theses*

With high resolution hydrodynamics simulations, we show that the optimal values of domain radius and grid resolution for the software *Sailfish* when simulating time-based eccentricity evolution of equal mass, non-circular accreting binaries in a circumbinary disk to be $r_{\rm out} \leq 15a$ and $\delta x / a \le 0.01 $. These values provide a useful guideline for optimizing the performance of simulation runs while maintaining scientific accuracy. Each artificial parameter is probed with 15 runs of 2000 orbits each.

Development And Testing Of A New Method For Velocity-Selecting White Dwarfs From Gaia By Galactic Population, 2023 Embry-Riddle Aeronautical University

#### Development And Testing Of A New Method For Velocity-Selecting White Dwarfs From Gaia By Galactic Population, Joseph Hammill

*Doctoral Dissertations and Master's Theses*

The detailed processes by which spiral galaxies form remains an open question in modern cosmology. Observations of the current configuration of spiral galaxies including the Milky Way reveal thin and thick disk and halo populations which must all be accounted for in formation theories and likely have distinct ages. Using the Milky Way as an example to probe this question, we are studying the formation history of these structures.

This work details our approach to age-dating the galaxy, velocity-selecting targets from a sample of white dwarfs from the Gaia DR3 catalog that have also been age-analysed using BASE-9. BASE-9 uses …

Cosmological Vector Fields And Constraining The Neutrino Masses, 2023 Dartmouth College

#### Cosmological Vector Fields And Constraining The Neutrino Masses, Avery J. Tishue

*Dartmouth College Ph.D Dissertations*

In this thesis I explore two main topics: the role and consequences of cosmological vector fields, and new ideas for constraining fundamental physics with state-of-the-art experiments. These topics are disparate in content and technique but unified in their attempt to leverage novel approaches to better understand longstanding questions in cosmology. These questions, such as ``What is causing the universe to accelerate today?'' and ``What are the neutrino masses?'', underpin the modern cosmological paradigm. They play a key role in our understanding of cosmic history, the formation of structure, and the fate of our universe. Answers to or hints about these …

Mapping Galactic Acceleration With Pulsar Timing, 2023 University of Connecticut

#### 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 …

Constraining H0 Via Extragalactic Parallax, 2023 University of Richmond

#### Constraining H0 Via Extragalactic Parallax, Nicholas Ferree

*Honors Theses*

We examine the prospects for measurement of the Hubble parameter 𝐻_{0 }via observation of the secular parallax of other galaxies due to our own motion relative to the cosmic microwave background rest frame. Peculiar velocities make distance measurements to individual galaxies highly uncertain, but a survey sampling many galaxies can still yield a precise 𝐻_{0} measurement. We use both a Fisher information formalism and simulations to forecast errors in 𝐻_{0} from such surveys, marginalizing over the unknown peculiar velocities. The optimum survey observes ∼ 102 galaxies within a redshift 𝐻_{0}max = 0.06. The required errors …

Characterization Of Extended Uncertainty Principle Black Holes, 2023 Loyola Marymount University

#### Characterization Of Extended Uncertainty Principle Black Holes, Juan Uribe, Jonas Mureika

*Honors Thesis*

Black Holes are special objects as they are at the intersection of Quantum Mechanics and General Relativity. A central tenant of quantum mechanics is the Uncertainty Principle that dictates we cannot know with complete certainty position and momentum at the same time. The Extended Uncertainty Principle introduces a position-related uncertainty correction L_* to account for General Relativity. In a previous paper, a black hole metric associated with the Extended Uncertainty Principle was derived, by modifying the metric function of a Schwarzschild black hole. This metric introduces near-horizon structures that should produce observable effects, such as love numbers, gravitational wave echoes, …

New Physics In The Age Of Precision Cosmology, 2023 Dartmouth College

#### New Physics In The Age Of Precision Cosmology, Vivian I. Sabla

*Dartmouth College Ph.D Dissertations*

The Lambda-cold dark matter (LCDM) model has become the standard model of cosmology because of its ability to reproduce a vast array of cosmological observations, from the earliest moments of our Universe, to the current period of accelerated expansion, which it does with great accuracy. However, the success of this model only distracts from its inherent flaws and ambiguities. LCDM is purely phenomenological, providing no physical explanation for the nature of dark matter, responsible for the formation and evolution of large-scale structure, and giving an inconclusive explanation for dark energy, which drives the current period of accelerated expansion.

Furthermore, cracks …

Stellar Atmosphere Models For Select Veritas Stellar Intensity Interferometry Targets, 2023 Embry-Riddle Aeronautical University

#### Stellar Atmosphere Models For Select Veritas Stellar Intensity Interferometry Targets, Jackson Ladd Sackrider, Jason P. Aufdenberg, Katelyn Sonnen

*Beyond: Undergraduate Research Journal*

Since 2020 the Very Energetic Radiation Imaging Telescope Array System (VERITAS) has observed 48 stellar targets using the technique of Stellar Intensity Interferometry (SII). Angular diameter measurements by VERITAS SII (VSII) in a waveband near 400 nm complement existing angular diameter measurements in the near-infrared. VSII observations will test fundamental predictions of stellar atmosphere models and should be more sensitive to limb darkening and gravity darkening effects than measurements in the near-IR, however, the magnitude of this difference has not been systematically explored in the literature. In order to investigate the synthetic interferometric (as well as spectroscopic) appearance of stars …

Eccentric Pairs: Analytic Gravitational Waves From Binary Black Holes In Elliptic Orbits, 2023 Marshall University

#### 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 …

Properties Of Slicing Conditions For Charged Black Holes, 2023 Bowdoin College

#### Properties Of Slicing Conditions For Charged Black Holes, Sean E. Li

*Honors Projects*

We consider an earlier analysis by Baumgarte and de Oliveira (2022) of static Bona-Massó slices of stationary, nonrotating, uncharged black holes, represented by Schwarzschild spacetimes, and generalize that approach to Reissner-Nordström (RN) spacetimes, representing stationary, nonrotating black holes that carry a nonzero charge. This charge is parametrized by the charge-to-mass ratio *λ* ≡ *Q*/*M*, where *M *is the black-hole mass and the charge *Q *may represent electrical charge or act as a placeholder for extensions of general relativity. We use a height-function approach to construct time-independent, spherically symmetric slices that satisfy a so-called Bona-Massó slicing condition. We …

Evolution Of Density And Velocity Perturbations In A Slowly Contracting Universe, 2023 University of Central Florida

#### Evolution Of Density And Velocity Perturbations In A Slowly Contracting Universe, Olivia R. Bitcon

*Honors Undergraduate Theses*

One focus of research in cosmology regards the growth of structure in the universe: how we end up with stars, galaxies, galaxy clusters, and large scale structure in a universe that appears homogeneous and isotropic on large scales. Using cosmological perturbation theory, we investigate the evolution of density and velocity perturbations corresponding to a universe that is slowly contracting (Ijjas and Steinhardt), testing with and comparing different values for the equation-of-state parameter. This allows for the comparison of the growth of large scale structure in scenarios including a matter-dominated expanding universe, a dark energy-dominated expanding universe, and now, an ekpyrotic …

Applications Of Digital Filters In Radio Astronomy, 2023 West Virginia University

#### Applications Of Digital Filters In Radio Astronomy, Joseph William Kania

*Graduate Theses, Dissertations, and Problem Reports*

The radio sky spans tens of orders of magnitude in length, density, and time.

In this thesis, using novel filtering techniques and two different telescopes,

we investigate two tracers of cosmic structure: Baryon Acoustic Oscillations

(BAOs) and Fast Radio Bursts (FRBs). BAOs formed as the universe cooled

after the Big Bang. BAOs provide a fiducial length scale of the universe

throughout cosmic time and thus can be used to understand how the universe

is evolving. FRBs are very bright, short timescale, bursts of as-yet unknown

origin which occur uniformly on the sky at a rate of a few thousand per …

Forecasting And Optimizing Sensitivity To Low-Frequency Gravitational Waves, 2023 West Virginia University

#### Forecasting And Optimizing Sensitivity To Low-Frequency Gravitational Waves, Andrew Ryan Kaiser

*Graduate Theses, Dissertations, and Problem Reports*

Pulsars are among the most exotic objects in our Universe. These rapidly

spinning, high magnetic field neutron stars can be used for a wide range of

scientific studies: from the makeup of their own extremely dense and poorly

understood interior to using their extremely regular signals to detect gravita-

tional waves (GWs). Pulsar timing continues to expand to broader communi-

ties, with larger and more sensitive radio telescopes planned and partnerships

between pulsar timing arrays (PTAs) that span the entire globe. A realm of

new physics with the detection of a background hum of gravitational waves

from black holes merging …

Black Holes, Disk Structures, And Cosmological Implications In E-Dimensional Space, 2022 Chapman University

#### 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.

Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies, 2022 University of Maine

#### Weak Gravitational Lensing Analysis In Two Superclusters Of Galaxies, Sarah B. Rice

*Electronic Theses and Dissertations*

Observations of the Universe on very large scales have shown it to be filled with galaxy clusters and superclusters connected by walls and filaments of galaxies, with vast areas mostly devoid of luminous matter separating them. It is widely accepted that the amount of luminous matter does not provide the mass needed to hold galaxies and galaxy clusters together, and the nature of the missing "dark matter" is one of the most prominent astrophysical mysteries today. Since dark matter interacts with luminous matter gravitationally, it stands to reason that dark matter might organize itself in a similar manner to luminous …