Bulletin of the American Physical Society
84th Annual Meeting of the APS Southeastern Section
Volume 62, Number 13
Thursday–Saturday, November 16–18, 2017; Milledgeville, Georgia
Session C3: Astrophysics and Gravitation |
Hide Abstracts |
Chair: Arash Bodaghee, Georgia College Room: MSU Building Donohoo Lounge |
Thursday, November 16, 2017 1:30PM - 1:42PM |
C3.00001: The X-ray population of the Milky Way as seen by NuSTAR Arash Bodaghee Launched in 2012, the Nuclear Spectroscopic Telescope Array (NuSTAR: Harrison et al. 2013) is NASA's newest space telescope devoted to observations in the X-rays (3-79 keV). The NuSTAR telescope consists of dual CCD detectors set 10-m away from an optics bench of incidence-grazing mirrors. Its unprecedented spatial and spectral resolution between 10 and 79 keV makes it a finely tuned instrument for performing surveys of the galactic plane where accreting neutron stars and black holes are plentiful. In this talk, I will present the most detailed maps of the Milky Way's central regions that have ever been produced in this energy range where we have uncovered around 100 accretion-powered X-ray sources. Detailed studies of the central supermassive black hole Sgr A* and the galactic X-ray population will be discussed, with insights into the accretion physics around a typical pulsating neutron star. [Preview Abstract] |
Thursday, November 16, 2017 1:42PM - 1:54PM |
C3.00002: An Amplified Standard Model Antonio Colella The Standard Model (SM) is the gold standard but must be amplified to include the graviton, dark matter, dark energy, and supersymmety. Four independent theories were amplified without sacrificing their integrities including: superstring, particle creation, Higgs forces, and spontaneous symmetry breaking. Amplifications of superstring theory included: 129 fundamental matter/force particles resided in Planck cubes as closed superstrings; and any object in our universe was defined by a volume of contiguous Planck cubes (It from Qubit concept). Amplifications of particle creation included: An intimate relationship existed between particle creation time and the particle's temperature (e.g., W$^{\mathrm{-}}$ at 10$^{\mathrm{-12}}$ s and 10$^{\mathrm{15\thinspace }}$K); matter creation began after inflation; by end of matter creation time, only 22 permanent matter/force particles remained. Amplifications of Higgs forces included: Extremely high temperatures caused spontaneous symmetry breaking, not Higgs forces; matter particles and their associated Higgs forces were one and inseparable; and spontaneous symmetry breaking was bidirectional (e.g. beta decay equation). These amplifications were summarized in an Amplified SM figure. [Preview Abstract] |
Thursday, November 16, 2017 1:54PM - 2:06PM |
C3.00003: Stellar Black Hole Example of the It from Qubit (IfQ) Concept Antonio Colella Stellar black hole (BH) example of IfQ consisted of volume of contiguous Planck cube information chunks. Four independent theories selectively amplified without sacrificing their integrities: superstring, Higgs forces, stellar BHs, and arrow of time. Superstring amplifications: 129 fundamental matter/force particles resided in Planck cubes as closed superstrings; any object in universe defined by a volume of contiguous Planck cubes; and super force superstring doughnut physical singularity existed at Planck cube's center at t $=$ 0. Higgs forces amplifications: extremely high early universe temperatures caused spontaneous symmetry breaking, not Higgs forces; matter particles and their associated Higgs forces were one and inseparable; spontaneous symmetry breaking was bidirectional (e.g. beta decay equation); and by end of matter creation time, only 22 permanent matter/force particles remained. Stellar BHs amplifications: stellar BHs were both quark star (matter) and associated BH (energy). Arrow of time amplifications: in a subset volume of precursor universe, entropy decreased without negating 2$^{\mathrm{nd}}$ Law of Thermodynamics. These amplifications summarized in two BH figures. [Preview Abstract] |
Thursday, November 16, 2017 2:06PM - 2:18PM |
C3.00004: Dark Matter-Baryonic Matter Radial Acceleration Relationship Edward Green Pandres has developed a theory which extends the geometrical structure of a real four-dimensional space-time via a field of orthonormal tetrads with an enlarged covariance group. This new group, called the conservation group, contains the group of diffeomorphisms as a proper subgroup. Using the curvature vector, $C_\mu$, we find a free-field Lagrangian density $C^\mu C_\mu \sqrt{-g}\,$. Spherically symmetric solutions for both the free field and the field with sources have been derived. The field equations require nonzero stress-energy tensors in regions where no source is present and thus may bring in dark matter and dark energy in a natural way. A simple model for a galaxy is given which satisfies our field equations. This model includes flat rotation curves. We compare our results with recently reported results of McGaugh, Lelli and Schombert which exhibit a new law between the observed radial acceleration and the baryonic radial acceleration. We find a slightly different model which relates these accelerations. In conjunction with our model, the McGaugh, Lelli and Schombert relation imply a new critical baryonic acceleration. This critical baryonic acceleration may be used to predict the radial velocity curve value by using the radius of the bulge. [Preview Abstract] |
Thursday, November 16, 2017 2:18PM - 2:30PM |
C3.00005: New Source and Test Masses and their Metrology for G Experiments Kofi Assumin-Gyimah Despite a long history of measurements, there are serious inconsistencies in our knowledge of the universal gravitational constant, $G$. The scatter in the measured values could be an indication of the incompleteness of general relativity, the current accepted description of gravity, or due to underestimated biases in the metrology of small forces. The metrology of test and source masses, typically made of high density metals, is of prime importance. There are however, some inherent limitations in the previous evaluations of systematic uncertainties associated with them. We propose to address these by developing high density transparent materials such as $PbWO_{4}$, for use in the next generation of experiments. This is motivated by the fact that density variation in glass and single crystals are significantly smaller than in metals and can be measured nondestructively. Consequently, we will develop a laser interferometer for the measurement of the internal density gradients of these masses. All components of the interferometer have been purchased and assembled in the Medium Energy Physics Lab at MSU. We will show some preliminary results from a 2x2x12 cm$^3$ $PbWO_{4}$ sample. [Preview Abstract] |
(Author Not Attending)
|
C3.00006: The Viability of Phantom Dark Energy as a Classical and Quantum Field in 1st-Order FLRW Space Kevin Ludwick In the standard cosmological framework of the 0th-order FLRW metric and the use of perfect fluids in the stress-energy tensor, dark energy with an equation-of-state parameter $w < -1$ (known as phantom dark energy) implies negative kinetic energy and vacuum instability when modeled as a scalar field. However, the accepted values for present-day $w$ from Planck and WMAP9 include a significant range of values less than $-1$. We consider a more accurate description of the universe through the 1st-order perturbing of the isotropic and homogeneous FLRW metric and the components of the stress-energy tensor and investigate whether a field with an apparent $w<-1$ may still have positive kinetic energy. Treating dark energy as a classical scalar field in this metric, we find that it is not as obvious as one might think that phantom dark energy has negative kinetic energy categorically. Analogously, we find that field models of quintessence dark energy ($w>-1$) do not necessarily have positive kinetic energy categorically. We then investigate the same question treating dark energy as a quantum field in 1st-order FLRW space-time and examining the expectation value of the stress-energy tensor for $w<-1$ using adiabatic expansion. [Preview Abstract] |
Thursday, November 16, 2017 2:42PM - 2:54PM |
C3.00007: Enhancing seismometer performance at low frequencies through tilt-decoupling Mohammad Afrough, Camillo Cocchieri, Niamke Buchanan, Katherine Dooley Although LIGO has detected four gravitational waves so far, people are still conducting research to improve the sensitivity of the detectors in different aspects. In the low-frequency band, one of the main sources of noise is seismic vibration. Lowering the noise level in this band helps us to follow the coalescence of compact binary systems earlier in their transformation and increase the signal-to-noise ratio. It also allows us to detect the merger of more massive objects. Hence, an isolation system is required to reduce the seismic noise. As a part of an active isolation system, inertial sensors play an important role in monitoring the seismic vibration and provide input for the isolation system. However, these sensors have a weakness. They cannot distinguish between translational motion and tilt motion and at low frequencies (less than 1 Hz), the signal is dominated by tilt motion. We designed and built a suspended seismometer to attenuate the transmitted tilt to the seismometer. We applied a tilt and translational motion to the system and measured the transfer function of the suspended seismometer. We also investigated the effect of air current and temperature gradients on the suspended seismometer by designing a thermal enclosure [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2025 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700