Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

35,069 Full-Text Articles 55,820 Authors 9,876,093 Downloads 294 Institutions

All Articles in Physics

Faceted Search

35,069 full-text articles. Page 7 of 1062.

Exploring Non-Orientable Topology: Deriving The Poincaré Conjecture And Possibility Of Experimental Vindication With Liquid Crystal, Victor Christianto, Florentin Smarandache 2023 University of New Mexico

Exploring Non-Orientable Topology: Deriving The Poincaré Conjecture And Possibility Of Experimental Vindication With Liquid Crystal, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

This review investigates the potential of non-orientable topology as a fundamental framework for understanding the Poincaré conjecture and its implications across various scientific disciplines. Integrating insights from Dokuchaev (2020), Rapoport, Christianto, Chandra, Smarandache (under review), and other pioneering works, this article explores the theoretical foundations linking non-orientable spaces to resolving the Poincaré conjecture and its broader implications in theoretical physics, geology, cosmology, and biology.


Patterned Heating Induced Propulsion, Saajid A. Aman 2023 Western University

Patterned Heating Induced Propulsion, Saajid A. Aman

Electronic Thesis and Dissertation Repository

This study explores propulsion effects generated by patterned heating acting on smooth and corrugated surfaces. The model problem assumes that the upper plate moves freely, and the lower plate is stationary, equipped with grooves, and exposed to spatially distributed heating. Our findings identify two distinct propulsion effects: thermal streaming and thermal drift. Thermal streaming occurs when given sufficient heating intensity with net flow in the left or right direction characterized by a pitchfork bifurcation. The efficiency of this technique can be controlled using the wavelength of heating. Thermal drift represents a pattern interaction effect. Its strength depends on the relative …


Analytic Distribution Of The Optimal Cross-Correlation Statistic For Stochastic Gravitational-Wave-Background Searches Using Pulsar Timing Arrays, ‪Jeffrey S. Hazboun, Patrick M. Meyers, Joseph D. Romano, Xavier Siemens, Anne M. Archibald 2023 The University of Texas Rio Grande Valley

Analytic Distribution Of The Optimal Cross-Correlation Statistic For Stochastic Gravitational-Wave-Background Searches Using Pulsar Timing Arrays, ‪Jeffrey S. Hazboun, Patrick M. Meyers, Joseph D. Romano, Xavier Siemens, Anne M. Archibald

Physics and Astronomy Faculty Publications and Presentations

We show via both analytical calculation and numerical simulation that the optimal cross-correlation statistic (OS) for stochastic gravitational-wave-background (GWB) searches using data from pulsar timing arrays follows a generalized chi-squared (GX2) distribution—i.e., a linear combination of chi-squared distributions with coefficients given by the eigenvalues of the quadratic form defining the statistic. This observation is particularly important for calculating the frequentist statistical significance of a possible GWB detection, which depends on the exact form of the distribution of the OS signal-to-noise ratio ρˆ ≡ Aˆ 2 gw=σ0 in the absence of GW-induced cross correlations (i.e., the null distribution). Previous discussions of …


Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-de la Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán 2023 Universidad de Guanajuato

Acoustically Levitated Whispering-Gallery Mode Microlasers, H. M. Reynoso-De La Cruz, E. D. Hernández-Campos, E. Ortiz-Ricardo, A. Martínez-Borquez, I. Rosas-Román, V. Contreras, G. Ramos-Ortiz, B. Mendoza-Santoyo, Cecilia Zurita-Lopez, R. Castro-Beltrán

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Acoustic levitation has become a crucial technique for contactless manipulation in several fields, particularly in biological applications. However, its application in the photonics field remains largely unexplored. In this study, we implement an affordable and innovative phased-array levitator that enables stable trapping in the air of micrometer dye-doped droplets, thereby enabling the creation of microlasers. For the first time, this paper presents a detailed performance of the levitated microlaser cavity, supported by theoretical analysis concerning the hybrid technology based on the combination of whispering-gallery modes and acoustic fields. The pressure field distribution inside the acoustic cavity is numerically solved and …


Dynamics And Scaling Of Particle Streaks In High-Reynolds-Number Turbulent Boundary Layers, Tim Berk, Filippo Coletti 2023 Utah State University

Dynamics And Scaling Of Particle Streaks In High-Reynolds-Number Turbulent Boundary Layers, Tim Berk, Filippo Coletti

Mechanical and Aerospace Engineering Faculty Publications

Inertial particles in wall-bounded turbulence are known to form streaks, but experimental evidence and predictive understanding of this phenomenon is lacking, especially in regimes relevant to atmospheric flows. We carry out wind tunnel measurements to investigate this process, characterizing the transport of microscopic particles suspended in turbulent boundary layers. The friction Reynolds number Re𝜏 = O(104) allows for significant scale separation and the emergence of large-scale motions, while the range of viscous Stokes number St+ = 18–870 is relevant to the transport of dust and fine sand in the atmospheric surface layer. We …


Enhanced Luminescence Efficiency In Eu-Doped Gan Superlattice Structures Revealed By Terahertz Emission Spectroscopy, Fumikazu Murakami, Atsushi Takeo, Brandon Mitchell, Volkmar Dierolf, Yasufumi Fujiwara, Masayoshi Tonouchi 2023 Osaka University

Enhanced Luminescence Efficiency In Eu-Doped Gan Superlattice Structures Revealed By Terahertz Emission Spectroscopy, Fumikazu Murakami, Atsushi Takeo, Brandon Mitchell, Volkmar Dierolf, Yasufumi Fujiwara, Masayoshi Tonouchi

Physics & Engineering Faculty Publications

Eu-doped Gallium nitride (GaN) is a promising candidate for GaN-based red light-emitting diodes, which are needed for future micro-display technologies. Introducing a superlattice structure comprised of alternating undoped and Eu-doped GaN layers has been observed to lead to an order-of-magnitude increase in output power; however, the underlying mechanism remains unknown. Here, we explore the optical and electrical properties of these superlattice structures utilizing terahertz emission spectroscopy. We find that ~0.1% Eu doping reduces the bandgap of GaN by ~40 meV and increases the index of refraction by ~20%, which would result in potential barriers and carrier confinement within a superlattice …


Search For Evidence Of Baryogenesis And Dark Matter In B+→Ψd+P Decays At Babar, J. P. Lees, V. Poireau, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. McKenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kravchenko, Milind Purohit, Et. Al. 2023 University of South Carolina

Search For Evidence Of Baryogenesis And Dark Matter In B+→Ψd+P Decays At Babar, J. P. Lees, V. Poireau, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kravchenko, Milind Purohit, Et. Al.

Faculty Publications

A new dark sector antibaryon, denoted ψD, could be produced in decays of B mesons. This Letter presents a search for B+ψD+p (and the charge conjugate) decays in e+e annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398 fb−1 are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10−7–10−5 are obtained at 90% confidence level for masses of 1.0<D< 4.3 GeV/c2. The result is also reinterpreted to provide …


When To Hold And When To Fold: Studies On The Topology Of Origami And Linkages, Mary Elizabeth Lee 2023 University of Massachusetts Amherst

When To Hold And When To Fold: Studies On The Topology Of Origami And Linkages, Mary Elizabeth Lee

Doctoral Dissertations

Linkages and mechanisms are pervasive in physics and engineering as models for a
variety of structures and systems, from jamming to biomechanics. With the increase
in physical realizations of discrete shape-changing materials, such as metamaterials,
programmable materials, and self-actuating structures, an increased understanding
of mechanisms and how they can be designed is crucial. At a basic level, linkages
or mechanisms can be understood to be rigid bars connected at pivots around which
they can rotate freely. We will have a particular focus on origami-like materials, an
extension to linkages with the added constraint of faces. Self-actuated versions typ-
ically start …


Assessing The Robustness Of Sound Horizon-Free Determinations Of The Hubble Constant, Tristan L. Smith, V. Poulin, T. Simon 2023 Swarthmore College

Assessing The Robustness Of Sound Horizon-Free Determinations Of The Hubble Constant, Tristan L. Smith, V. Poulin, T. Simon

Physics & Astronomy Faculty Works

The Hubble tension can be addressed by modifying the sound horizon (rs) before recombination, triggering interest in early universe estimates of the Hubble constant, H0, independent of rs. Constraints on H0 from an rs-free analysis of the full shape BOSS galaxy power spectra within Λ CDM were recently reported and used to comment on the viability of physics beyond Λ CDM. Here we demonstrate that rs-free analyses with current data depend on both the model and the priors placed on the cosmological parameters, such that Λ CDM analyses …


Detailed Characterization Of A Khz-Rate Laser-Driven Fusion At A Thin Liquid Sheet With A Neutron Detection Suite, Benjamin M. Knight, Connor Gautam, Colton R. Stoner, Bryan V. Egner, Joseph R. Smith, Christopher M. Orban, Juan J. Manfredi, Kyle Frische, Michael L. Dexter, Enam A. Chowdury, Anil K. Patniak 2023 Air Force Institute of Technology

Detailed Characterization Of A Khz-Rate Laser-Driven Fusion At A Thin Liquid Sheet With A Neutron Detection Suite, Benjamin M. Knight, Connor Gautam, Colton R. Stoner, Bryan V. Egner, Joseph R. Smith, Christopher M. Orban, Juan J. Manfredi, Kyle Frische, Michael L. Dexter, Enam A. Chowdury, Anil K. Patniak

Faculty Publications

We present detailed characterization of laser driven fusion and neutron production (∼105/second) employing 8 mJ, 40fs laser pulses on a thin (< 1 µm) D2O liquid sheet employing a measurement suite. At relativistic intensity (∼5×1018W/cm2) and high repetition-rate (1 kHz), the system produces consistent D-D fusion, allowing for consistent neutron generation. Evidence of D-D fusion neutron production is verified b y a measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a 3He proportional counter, and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows …


Perovskite Cspbbr3 Solar Cells With Novel Hole-Transporting Layer Of Metal Complexes, Liqiu Zheng, Evynn S. Jackson, Ny'kesha S. Warren, Robert Owor, Zhongrui Li 2023 Albany state university

Perovskite Cspbbr3 Solar Cells With Novel Hole-Transporting Layer Of Metal Complexes, Liqiu Zheng, Evynn S. Jackson, Ny'kesha S. Warren, Robert Owor, Zhongrui Li

Georgia Journal of Science

For the first time, the novel application of Schiff-base copper complexes in all-inorganic perovskite CsBrBr3 solar cells has been explored and turns out they could be utilized as effective hole-transporting materials. Schiff-base copper complexes with halogen ligands (R=Cl and Br) are synthesized with an ease approach at a low cost, both of which exhibit decent power conversion efficiency of 4.55% and 5.71%, respectively, when being constructed into solar devices as hole transport layers. Thanks to high thermal/chemical stability of those Schiff-base metal complexes, the strengthened stability was achieved which is comparable to that of carbon-based CsBrBr3 solar cells. …


Search For Exotic Higgs Boson Decay To Multiple B-Quarks With The Atlas Detector At Lhc Using Machine Learning Methods, Yuan-Tang Chou 2023 University of Massachusetts Amherst

Search For Exotic Higgs Boson Decay To Multiple B-Quarks With The Atlas Detector At Lhc Using Machine Learning Methods, Yuan-Tang Chou

Doctoral Dissertations

The discovery of the Higgs boson has opened up new possibilities for investigating physics beyond the Standard Model (SM). New particles may interact with the SM through the Higgs boson, and deviations from SM predictions can indicate the presence of new physics. This dissertation focuses on the search for exotic Higgs decay, $H\rightarrow aa \rightarrow (b\bbar)(b\bbar)$ where a is a new scalar boson and focuses on the case where the Higgs boson is produced in association with a Z boson. The data were collected by the ATLAS detector at the Large Hadron Collider at center-of-mass energy $\sqrt{s} =~13~\TeV$ from 2015 …


Experiments With Monopoles, Rings And Knots In Spinor Bose-Einstein Condensates, Alina A. Blinova 2023 University of Massachusetts Amherst

Experiments With Monopoles, Rings And Knots In Spinor Bose-Einstein Condensates, Alina A. Blinova

Doctoral Dissertations

Topological excitations are ubiquitous in nature, their charge being a naturally-quantized, conserved quantity that can exhibit particle-like behavior. Spinor Bose-Einstein condensates (BECs) are an exceptionally versatile system for the study and exploration of topological excitations. Between the spin-1 and spin-2 87Rb condensates there are seven possible broken-symmetry magnetic phases, with each one hosting unique opportunities for topological defects. We have created and observed several novel topological excitations in a spinor 87Rb BEC. In this dissertation I present and discuss three principal experimental findings: (1) The discovery of an Alice ring, or a half-quantum vortex ring, emerging from a …


Tev-Scale Lepton Number Violation: 0Νββ Decay, The Origin Of Matter, And Energy Frontier Probes, Sebastian Urrutia Quiroga 2023 University of Massachusetts Amherst

Tev-Scale Lepton Number Violation: 0Νββ Decay, The Origin Of Matter, And Energy Frontier Probes, Sebastian Urrutia Quiroga

Doctoral Dissertations

Lepton number violation (LNV) offers promising theoretical pathways to several unresolved problems in particle and nuclear physics and unveils a diverse range of phenomenology across different energy scales. TeV-scale LNV is especially relevant for both its experimental accessibility and its broad-ranging impact, making it a key area of interest for both theoretical and experimental physicists. In this thesis, we explore three distinct scenarios within the LNV research landscape. Our first analysis concerns the implications of TeV-scale LNV effects in thermal leptogenesis and its complementary sensitivity in neutrinoless double beta (0νββ) decay and collider experiments. We employed a simplified model to …


Thermal Conductivity And Mechanical Properties Of Interlayer-Bonded Graphene Bilayers, Afnan Mostafa 2023 University of Massachusetts Amherst

Thermal Conductivity And Mechanical Properties Of Interlayer-Bonded Graphene Bilayers, Afnan Mostafa

Masters Theses

Graphene, an allotrope of carbon, has demonstrated exceptional mechanical, thermal, electronic, and optical properties. Complementary to such innate properties, structural modification through chemical functionalization or defect engineering can significantly enhance the properties and functionality of graphene and its derivatives. Hence, understanding structure-property relationships in graphene-based metamaterials has garnered much attention in recent years. In this thesis, we present molecular dynamics studies aimed at elucidating structure-property relationships that govern the thermomechanical response of interlayer-bonded graphene bilayers.

First, we present a systematic and thorough analysis of thermal transport in interlayer-bonded twisted bilayer graphene (IB-TBG). We find that the introduction of interlayer C-C …


The Fate Of The Crossbridge After Phosphate Rebinding: Implications For Fatigue, Christopher P. Marang 2023 University of Massachusetts Amherst

The Fate Of The Crossbridge After Phosphate Rebinding: Implications For Fatigue, Christopher P. Marang

Doctoral Dissertations

In response to repeated intense contractile activity, a muscle’s ability to generate force decreases due to the created state of muscular fatigue. This compromised force production state is dependent on changes within the microenvironment of muscle thought to alter the function of the force generating, contractile protein myosin. For example, phosphate (Pi), elevated during fatigue, has been suggested to alter how myosin generates force. However, the effects of Pi are not straightforward, as muscle fiber data suggest that Pi's interaction with myosin may be force-dependent. In particular, Pi has no effect on maximal shortening …


Measurement Of Additional Radiation In The Initial-State-Radiation Processes E+E- →Μ+Μ- Y And E+E- → ℼ+ℼ- Y At Babar, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. McKenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kozyrev, Milind Purohit, Et. Al. 2023 University of South Carolina

Measurement Of Additional Radiation In The Initial-State-Radiation Processes E+E- →Μ+Μ- Y And E+E- → ℼ+ℼ- Y At Babar, J. P. Lees, V. Poireau, V. Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, E. A. Kozyrev, Milind Purohit, Et. Al.

Faculty Publications

A dedicated measurement of additional radiation in e+e → µ+µγ and e+eπ+πγ initial-state-radiation events is presented using the full BABAR data sample. For the first time results are presented at next-to- and next-to-next-to-leading order, with one and two additional photons, respectively, for radiation from the initial and final states. Comparison with predictions from PHOKHARA and AFKQED Monte Carlo generators is performed, revealing discrepancies in the one-photon rates and angular distributions for the former. This disagreement has a negligible effect on the BABAR measurement of …


Employing A Fractional Basis Set To Solve Nonlinear Multidimensional Fractional Differential Equations, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis 2023 The University of Texas Rio Grande Valley

Employing A Fractional Basis Set To Solve Nonlinear Multidimensional Fractional Differential Equations, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis

Physics and Astronomy Faculty Publications and Presentations

Fractional-order partial differential equations have gained significant attention due to their wide range of applications in various fields. This paper employed a novel technique for solving nonlinear multidimensional fractional differential equations by means of a modified version of the Bernstein polynomials called the Bhatti-fractional polynomials basis set. The method involved approximating the desired solution and treated the resulting equation as a matrix equation. All fractional derivatives are considered in the Caputo sense. The resulting operational matrix was inverted, and the desired solution was obtained. The effectiveness of the method was demonstrated by solving two specific types of nonlinear multidimensional fractional …


Influence Of Thickness And Capping Materials On The Static And Dynamic Properties Of Ferrimagnetic Thin Films, Noha Alzahrani 2023 University of South Florida

Influence Of Thickness And Capping Materials On The Static And Dynamic Properties Of Ferrimagnetic Thin Films, Noha Alzahrani

USF Tampa Graduate Theses and Dissertations

Spintronics traditionally relied on ferromagnetic materials for their strong spin properties but facedissues like large stray magnetic fields. To address these challenges, researchers turned to antiferromagnetic materials with fast spin dynamics, due to their zero net magnetic moment but the lack of a net spin moment complicated operation. In this context, ferrimagnetic materials have emerged as promising alternatives. They combine ferromagnetic and antiferromagnetic traits and feature different magnetic ions in their sublattices. This dissertation explores how film thickness and capping materials affect the properties of ferrimagnetic thin films. Rare-earth transition metal ferrimagnetic amorphous alloys have garnered attention in the realm …


Weak Measurements And Quantum-To-Classical Transitions In Free Electron–Photon Interactions, Yiming Pan, Eliahu Cohen, Ebrahim Karimi, Avraham Gover, Norbert Schönenberger, Tomáš Chlouba, Kangpeng Wang, Saar Nehemia, Peter Hommelhoff, Ido Kaminer, Yakir Aharonov 2023 ShanghaiTech University

Weak Measurements And Quantum-To-Classical Transitions In Free Electron–Photon Interactions, Yiming Pan, Eliahu Cohen, Ebrahim Karimi, Avraham Gover, Norbert Schönenberger, Tomáš Chlouba, Kangpeng Wang, Saar Nehemia, Peter Hommelhoff, Ido Kaminer, Yakir Aharonov

Mathematics, Physics, and Computer Science Faculty Articles and Research

How does the quantum-to-classical transition of measurement occur? This question is vital for both foundations and applications of quantum mechanics. Here, we develop a new measurement-based framework for characterizing the classical and quantum free electron–photon interactions and then experimentally test it. We first analyze the transition from projective to weak measurement in generic light–matter interactions and show that any classical electron-laserbeam interaction can be represented as an outcome of weak measurement. In particular, the appearance of classical point-particle acceleration is an example of an amplified weak value resulting from weak measurement. A universal factor, exp(-Γ2/2) , quantifies the …


Digital Commons powered by bepress