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All Articles in Cosmology, Relativity, and Gravity

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Dark Matter Production Beyond The Thermal Wimp Paradigm: An Exploration Of Early Matter Domination Scenarios, Jacek Ksawery Osinski 2019 University of New Mexico

Dark Matter Production Beyond The Thermal Wimp Paradigm: An Exploration Of Early Matter Domination Scenarios, Jacek Ksawery Osinski

Physics & Astronomy ETDs

In the standard thermal history of the Universe, the energy density is dominated by radiation throughout the postinflationary era, until matter-radiation equality after big bang nucleosynthesis (BBN). However, we currently do not have any observational probes of the pre-BBN period, and radiation domination (RD) is therefore an assumption. Generic early Universe models predict the presence of additional components in the postinflationary Universe which can lead to periods of nonstandard evolution before the onset of BBN. A prominent example of such a period is a phase of early matter domination (EMD) in which the Universe undergoes matter-dominated expansion for a time, …


New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd 2019 University of New Mexico

New Foundation In The Sciences: Physics Without Sweeping Infinities Under The Rug, Florentin Smarandache, Victor Christianto, Robert Neil Boyd

Branch Mathematics and Statistics Faculty and Staff Publications

It is widely known among the Frontiers of physics, that “sweeping under the rug” practice has been quite the norm rather than exception. In other words, the leading paradigms have strong tendency to be hailed as the only game in town. For example, renormalization group theory was hailed as cure in order to solve infinity problem in QED theory. For instance, a quote from Richard Feynman goes as follows: “What the three Nobel Prize winners did, in the words of Feynman, was "to get rid of the infinities in the calculations. The infinities are still there, but now they can …


Morphological Signatures Induced By Dust Back Reactions In Discs With An Embedded Planet, Chao-Chin Yang, Zhaohuan Zhu 2019 University of Nevada, Las Vegas

Morphological Signatures Induced By Dust Back Reactions In Discs With An Embedded Planet, Chao-Chin Yang, Zhaohuan Zhu

Physics & Astronomy Faculty Research

Recent observations have revealed a gallery of substructures in the dust component of nearby protoplanetary discs, including rings, gaps, spiral arms, and lopsided concentrations. One interpretation of these substructures is the existence of embedded planets. Not until recently, however, most of the modelling effort to interpret these observations ignored the dust back reaction to the gas. In this work, we conduct local-shearing-sheet simulations for an isothermal, inviscid, non-self-gravitating, razor-thin dusty disc with a planet on a fixed circular orbit. We systematically examine the parameter space spanned by planet mass (0.1Mth ≤ Mp ≤ 1Mth, where Mth is the thermal mass), …


Graded Quivers, Generalized Dimer Models And Toric Geometry, Sebastián Franco, Azeem Hasan 2019 CUNY Graduate Center

Graded Quivers, Generalized Dimer Models And Toric Geometry, Sebastián Franco, Azeem Hasan

Publications and Research

The open string sector of the topological B-model on CY (m+2)-folds is described by m-graded quivers with superpotentials. This correspondence extends to general m the well known connection between CY (m+2)-folds and gauge theories on the world-volume of D(5-2m)-branes for m = 0, ..., 3. We introduce m-dimers, which fully encode the m-graded quivers and their superpotentials, in the case in which the CY (m+2)-folds are toric. Generalizing the well known m = 1,2 cases, m-dimers significantly simplify the connection between geometry and m-graded quivers. A key …


Nonideal Mhd Simulation Of Hl Tau Disk: Formation Of Rings, Xiao Hu, Zhaohuan Zhu, Satoshi Okuzumi, Xue-Ning Bai, Lile Wang, Kengo Tomida, James M. Stone 2019 University of Nevada, Las Vegas

Nonideal Mhd Simulation Of Hl Tau Disk: Formation Of Rings, Xiao Hu, Zhaohuan Zhu, Satoshi Okuzumi, Xue-Ning Bai, Lile Wang, Kengo Tomida, James M. Stone

Physics & Astronomy Faculty Research

Recent high-resolution observations unveil ring structures in circumstellar disks. The origin of these rings has been widely investigated under various theoretical scenarios. In this work we perform global 3D nonideal MHD simulations including effects from both ohmic resistivity and ambipolar diffusion (AD) to model the HL Tau disk. The nonideal MHD diffusion profiles are calculated based on the global dust evolution calculation including sintering effects. Disk ionization structure changes dramatically across the snow line due to the change of dust size distribution close to the snow line of major volatiles. We find that accretion is mainly driven by disk wind. …


P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales 2019 Andrews University

P-13 Astronomy From Ripples In Spacetime, Tiffany Summerscales

Celebration of Research and Creative Scholarship

The LIGO and Virgo detectors have made a total of 11 confirmed measurements of gravitational waves, the faint ripples in the fabric of spacetime predicted by Einstein’s theory of general relativity. Ten of these gravitational wave events were caused by the inspiral, collision, and merging of a pair of black holes and the remaining event by a pair of neutron stars. These measurements have helped us learn about the objects that produced the gravitational waves. Regular candidate detections are now shared in real time with both astronomers and the public.


Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda 2019 University of Louisville

Galaxy And Mass Assembly: A Comparison Between Galaxy-Galaxy Lens Searches In Kids/Gama, Shawn Knabel, Benne Holwerda

Posters-at-the-Capitol

Strong gravitational lenses are cases where a distant background galaxy is located directly behind a massive foreground galaxy, whose gravity causes the light from the background galaxy to bend around the foreground galaxy. In addition to being visually stunning, these rare events are useful laboratories for furthering our understanding of gravity and cosmology and to determine properties, such as the mass and dark matter content, of the lensing galaxies themselves. The trouble is finding enough of these strong gravitational lenses for further study. The immensity of the catalogs being collected by state-of-the-art telescopes requires equally innovative methods for interpreting that …


Diagnosing 0.1–10 Au Scale Morphology Of The Fu Ori Disk Using Alma And Vlti/Gravity, Hauyu Baobab Liu, Antoine Merand, Joel D. Green, Sebastian Perez, Antonio S. Hales, Yao-Lun Yang, Michael M. Dunham, Yasuhiro Hasegawa, Thomas Henning, Roberto Galvin-Madrid, Agnes Kospal, Michihiro Takami, Eduardo I. Vorobyov, Zhaohuan Zhu 2019 Academia Sinica Institute of Astronomy and Astrophysics

Diagnosing 0.1–10 Au Scale Morphology Of The Fu Ori Disk Using Alma And Vlti/Gravity, Hauyu Baobab Liu, Antoine Merand, Joel D. Green, Sebastian Perez, Antonio S. Hales, Yao-Lun Yang, Michael M. Dunham, Yasuhiro Hasegawa, Thomas Henning, Roberto Galvin-Madrid, Agnes Kospal, Michihiro Takami, Eduardo I. Vorobyov, Zhaohuan Zhu

Physics & Astronomy Faculty Research

We report new Atacama Large Millimeter/submillimeter Array Band 3 (86–100 GHz; ~80 mas angular resolution) and Band 4 (146–160 GHz; ~50 mas angular resolution) observations of the dust continuum emission toward the archetypal and ongoing accretion burst young stellar object FU Ori, which simultaneously covered its companion, FU Ori S. In addition, we present near-infrared (2–2.45 μm) observations of FU Ori taken with the General Relativity Analysis via VLT InTerferometrY (GRAVITY; ~1 mas angular resolution) instrument on the Very Large Telescope Interferometer (VLTI). We find that the emission in both FU Ori and FU Ori S at (sub)millimeter and near-infrared …


A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga 2019 Centro de Astrobiologia

A Global View Of The Inner Accretion And Ejection Flow Around Super Massive Black Holes, Margherita Giustini, Daniel Proga

Physics & Astronomy Faculty Research

Context. Understanding the physics and geometry of accretion and ejection around super massive black holes (SMBHs) is important to understand the evolution of active galactic nuclei (AGN) and therefore of the large scale structures of the Universe. Aims. We aim at providing a simple, coherent, and global view of the sub-parsec accretion and ejection flow in AGN with varying Eddington ratio, ṁ, and black hole mass, MBH. Methods. We made use of theoretical insights, results of numerical simulations, as well as UV and X-ray observations to review the inner regions of AGN by including different accretion and ejection modes, with …


Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, L. Staveley-Smith, T. Westmeier, M. Whiting, S. -H. Oh, B. Koribalski, J. Wang, O. I. Wong, G. Bekiaris, L. Cortese, A. Elagali, D. Kleiner, K. Lee-Waddell, Juan P. Madrid, A. Popping, J. Rhee, T. N. Reynolds, J. D. Collier, C. J. Phillips, M. A. Voronkov, O. Mueller, H. Jerjen 2019 University of Western Australia

Wallaby Early Science − V. Askap Hi Imaging Of The Lyon Group Of Galaxies 351, B. Q. For, L. Staveley-Smith, T. Westmeier, M. Whiting, S. -H. Oh, B. Koribalski, J. Wang, O. I. Wong, G. Bekiaris, L. Cortese, A. Elagali, D. Kleiner, K. Lee-Waddell, Juan P. Madrid, A. Popping, J. Rhee, T. N. Reynolds, J. D. Collier, C. J. Phillips, M. A. Voronkov, O. Mueller, H. Jerjen

Physics and Astronomy Faculty Publications and Presentations

We present an HI study of the galaxy group LGG 351 usingWidefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY) early science data observed with the Australian Square Kilometre Array Pathfinder (ASKAP). LGG 351 resides behind the M 83 group at a velocity range (cz) of ∼3500–4800 km s−1 within the rich Hydra-Centaurus overdensity region. We detect 40 sources with the discovery of a tidally interacting galaxy pair and two new HI sources that are not presented in previous optical catalogues. 23 out of 40 sources have new redshifts derived from the new HI data. This study is the largest WALLABY …


Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters 2019 University of Nevada, Las Vegas

Photoionization Calculations Of The Radiation Force Due To Spectral Lines In Agns, Randall C. Dannen, Daniel Proga, Timothy R. Kallman, Tim Waters

Physics & Astronomy Faculty Research

One of the main mechanisms that could drive mass outflows in active galactic nuclei (AGNs) is radiation pressure due to spectral lines. Although straightforward to understand, the actual magnitude of the radiation force is challenging to compute because the force depends on the physical conditions in the gas, as well as the strength, spectral energy distribution (SED), and geometry of the radiation field. We present results from our photoionization and radiation transfer calculations of the force multiplier, M(ξ, t), using the same radiation field to compute the gas photoionization and thermal balance. We assume low gas density (n = 104 …


On Newtonian Dynamics With A Variable Earth Mass: Geodetic Evidence And Its Implications On Pioneer Spacecraft Anomaly And Lageos Satellite, Victor Christianto, Florentin Smarandache 2019 University of New Mexico

On Newtonian Dynamics With A Variable Earth Mass: Geodetic Evidence And Its Implications On Pioneer Spacecraft Anomaly And Lageos Satellite, Victor Christianto, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Around 3 decades ago, Jayant Narlikar & Halton Arp argued on possible variable mass hypothesis cosmology (VMH). In the meantime, the Earth expansion problem has attracted great interest, and recent study gives geodetic evidence that the Earth has been expanding, at least over the recent several decades. Therefore, in the present article discusses some interesting effects related to varying G, but here we argue that instead of varying G we can think of varying mass (M). Among other things we discuss receding planets from the Sun, calculation of Pioneer spacecraft anomaly as proposed by B.G. Sidharth, and also possible slight …


Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo 2019 Humboldt State University

Preparing A Database Of Extremely High Velocity Outflows In Quasars, Griffin Kowash, Carla P. Quintero, Sean S. Haas, Paola Rodriguez Hidalgo

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Viewing Angle Constraints On S190425z And S190426c And The Joint Gravitational-Wave/Gamma-Ray Detection Fractions For Binary Neutron Star Mergers, Hao-Ran Song, Shun-Ke Ai, Min-Hao Wang, Nan Xing, He Gao, Bing Zhang 2019 Beijing Normal University

Viewing Angle Constraints On S190425z And S190426c And The Joint Gravitational-Wave/Gamma-Ray Detection Fractions For Binary Neutron Star Mergers, Hao-Ran Song, Shun-Ke Ai, Min-Hao Wang, Nan Xing, He Gao, Bing Zhang

Physics & Astronomy Faculty Research

The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo scientific collaboration (LVC) detected two binary neutron star (BNS) merger candidates, S190425z and S190426c. The Fermi-Gamma-ray Burst Monitor (GBM) observed 55.6% (for S190425z) and 100% (for S190426c) of the probability regions of both events at the respective merger times, but no gamma-ray burst (GRB) was detected in either case. The derived luminosity upper limits suggest that a short GRB similar to GRB 170817A would not be detectable for both cases due to their distances, which are larger than that of GW170817. Assuming that the jet profile obtained from GW170817/GRB 170817A is quasi-universal …


The Ages Of The Thin Disk, Thick Disk, And The Halo From Nearby White Dwarfs, Mukremin Kilic, Ted von Hippel, Jeffrey A. Munn, Hugh C. Harris, James W. Liebert, et al. 2019 University of Oklahoma

The Ages Of The Thin Disk, Thick Disk, And The Halo From Nearby White Dwarfs, Mukremin Kilic, Ted Von Hippel, Jeffrey A. Munn, Hugh C. Harris, James W. Liebert, Et Al.

Ted von Hippel

We present a detailed analysis of the white dwarf luminosity functions derived from the local 40 pc sample and the deep proper motion catalog of Munn et al. (2014, 2017). Many of the previous studies ignored the contribution of thick disk white dwarfs to the Galactic disk luminosity function, which results in an erronous age measurement. We demonstrate that the ratio of thick/thin disk white dwarfs is roughly 20% in the local sample. Simultaneously fitting for both disk components, we derive ages of 6.8-7.0 Gyr for the thin disk and 8.7 ± 0.1 Gyr for the thick disk from the …


Stellar Populations And The White Dwarf Mass Function: Connections To Supernova Ia Luminosities, Ted von Hippel, G. D. Bothum, R. A. Schommer 2019 University of Wisconsin

Stellar Populations And The White Dwarf Mass Function: Connections To Supernova Ia Luminosities, Ted Von Hippel, G. D. Bothum, R. A. Schommer

Ted von Hippel

We discuss the luminosity function of SNe Ia under the assumption that recent evidence for dispersion in this standard candle is related to variations in the white dwarf mass function (WDMF) in the host galaxies. We develop a simple parameterization of the WDMF as a function of age of a stellar population and apply this to galaxies of different morphological types. We show that this simplified model is consistent with the observed WDMF of Bergeron et al. (1992) for the solar neighborhood. Our simple models predict that WDMF variations can produce a range of more than 1.8 mag in MB(SN …


Magnetospherically-Trapped Dust And A Possible Model For The Unusual Transits At Wd1145+017, J. Farihi, Ted von Hippel, J. E. Pringle 2019 University College London

Magnetospherically-Trapped Dust And A Possible Model For The Unusual Transits At Wd1145+017, J. Farihi, Ted Von Hippel, J. E. Pringle

Ted von Hippel

The rapidly evolving dust and gas extinction observed towardsWD1145+017 has opened a real-time window onto the mechanisms for destruction-accretion of planetary bodies onto white dwarf stars, and has served to underline the importance of considering the dynamics of dust particles around such objects. Here it is argued that the interaction between (charged) dust grains and the stellar magnetic field is an important ingredient in understanding the physical distribution of infrared emitting particles in the vicinity of such white dwarfs. These ideas are used to suggest a possible model for WD 1145+017 in which the unusual transit shapes are caused by …


Galactic Open Clusters, Ted von Hippel 2019 University of Texas

Galactic Open Clusters, Ted Von Hippel

Ted von Hippel

The study of open clusters has a classic feel to it since the subject predates anyone alive today. Despite the age of this topic, I show via an ADS search that its relevance and importance in astronomy has grown faster in the last few decades than astronomy in general. This is surely due to both technical reasons and the interconnection of the field of stellar evolution to many branches of astronomy. In this review, I outline what we know today about open clusters and what they have taught us about a range of topics from stellar evolution to Galactic structure …


One-Note-Samba Approach To Cosmology, Florentin Smarandache, Victor Christianto 2019 University of New Mexico

One-Note-Samba Approach To Cosmology, Florentin Smarandache, Victor Christianto

Branch Mathematics and Statistics Faculty and Staff Publications

Inspired by One Note Samba, a standard jazz repertoire, we present an outline of Bose-Einstein Condensate Cosmology. Although this approach seems awkward and a bit off the wall at first glance, it is not impossible to connect altogether BEC, Scalar Field Cosmology and Feshbach Resonance with Ermakov-Pinney equation. We also briefly discuss possible link with our previous paper which describes Newtonian Universe with Vortex in terms of Ermakov equation.


The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement, Michael S. Fusco 2019 University of Arkansas, Fayetteville

The Disk Structure Of Late Type Galaxies: Determining The Black Hole Mass Function Of Low Surface Brightness Galaxies Through Logarithmic Spiral Arm Pitch Angle Measurement, Michael S. Fusco

Graduate Theses and Dissertations

This dissertation pertains to the geometric structure of late type (spiral) galaxies, specifically on the relation between the logarithmic spiral pitch angle of the galactic spiral arms with other properties of the galaxy, such as central Supermassive Black Hole (SMBH) mass. Our work continues a study of the Black Hole Mass Function (BHMF) in local galaxies by recording the pitch angles of spiral galaxies with lower surface brightness than were previously included. We also conduct a case study on the structure of an interestingly shaped galaxy, UGC 4599. Previous studies on the topic of spiral arm pitch angles have measured …


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