Open Access. Powered by Scholars. Published by Universities.®
Cosmology, Relativity, and Gravity Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Stars, Interstellar Medium and the Galaxy (10)
- Physics (8)
- External Galaxies (4)
- Social and Behavioral Sciences (4)
- Business (3)
-
- Communication (3)
- Communication Technology and New Media (3)
- Computer Sciences (3)
- E-Commerce (3)
- Graphics and Human Computer Interfaces (3)
- Management Information Systems (3)
- Other Astrophysics and Astronomy (3)
- Other Computer Sciences (3)
- Science and Technology Studies (3)
- Strategic Management Policy (3)
- Technology and Innovation (3)
- Elementary Particles and Fields and String Theory (2)
- Instrumentation (2)
- Applied Mathematics (1)
- Arts and Humanities (1)
- Christianity (1)
- Condensed Matter Physics (1)
- Education (1)
- Ethics in Religion (1)
- Fluid Dynamics (1)
- Geometry and Topology (1)
- Higher Education (1)
- Institution
-
- Wayne State University (6)
- SelectedWorks (5)
- Dartmouth College (2)
- Embry-Riddle Aeronautical University (2)
- Selected Works (2)
-
- University of Arkansas, Fayetteville (2)
- University of Richmond (2)
- Bard College (1)
- Chapman University (1)
- Loyola University Chicago (1)
- Marshall University (1)
- Munster Technological University (1)
- Olivet Nazarene University (1)
- The University of San Francisco (1)
- University of Massachusetts Amherst (1)
- University of Nevada, Las Vegas (1)
- Western University (1)
- Keyword
-
- Accretion (7)
- Individual (5)
- Accretion disks (4)
- Binaries (4)
- Cosmology (4)
-
- Neutron (4)
- Stars (4)
- X-rays (4)
- Accretion discs (3)
- Astrophysics (3)
- Pulsars (3)
- Black Holes (2)
- Black hole physics (2)
- Computational Physics (2)
- Cosmology observations (2)
- Galaxies (2)
- Gauge-gravity correspondence (2)
- General relativity (2)
- Holography and condensed matter physics (AdS/CMT) (2)
- Information Warfare (2)
- Theory of Abstraction (2)
- 1.3 PHYSICAL SCIENCES (1)
- Abutment (1)
- Active (1)
- Active galaxies (1)
- Approximations (1)
- Aql X-1 (1)
- Arab Spring (1)
- Astronomy (1)
- Atomic Physics (1)
- Publication
-
- Physics and Astronomy Faculty Research Publications (6)
- Manoj Maharaj (3)
- Dartmouth Scholarship (2)
- Physics Faculty Publications (2)
- Publications (2)
-
- Subhajit Kumar Ganguly (2)
- Daniela Calzetti (1)
- Electronic Thesis and Dissertation Repository (1)
- Eric Addison (1)
- Faculty Scholarship – Geology (1)
- Festival of Communities: UG Symposium (Posters) (1)
- Journal of the Arkansas Academy of Science (1)
- Mathematics, Physics, and Computer Science Faculty Articles and Research (1)
- Physical Sciences Publications (1)
- Physics Faculty Research (1)
- Physics and Astronomy (1)
- Physics: Faculty Publications and Other Works (1)
- Robert A McNees IV (1)
- Senior Projects Spring 2011 (1)
- University Libraries Faculty Publications and Presentations (1)
- Publication Type
Articles 1 - 30 of 31
Full-Text Articles in Cosmology, Relativity, and Gravity
Correlation Of Inflation-Produced Magnetic Fields With Scalar Fluctuations, Robert R. Caldwell, Leonardo Motta, Marc Kamionkowski
Correlation Of Inflation-Produced Magnetic Fields With Scalar Fluctuations, Robert R. Caldwell, Leonardo Motta, Marc Kamionkowski
Dartmouth Scholarship
If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field—e.g. the inflaton, curvaton, or Ricci scalar—then these magnetic fields may be correlated with primordial density perturbations, opening a new window to the study of non-Gaussianity in cosmology. In order to illustrate, we couple electromagnetism to an auxiliary scalar field in a de Sitter background. We calculate the power spectra for scalar-field perturbations and magnetic fields, showing how a scale-free magnetic-field spectrum with rms amplitude of ∼nG at Mpc …
The Hubble Space Telescope * Cluster Supernova Survey. Ii. The Type Ia Supernova Rate In High-Redshift Galaxy Clusters, K Barbary, G Aldering, R Amanullah, M Brodwin, N Connolly, Ks Dawson, M Doi, P Eisenhardt, L Faccioli, V Fadeyev, Hk Fakhouri, As Fruchter, D G. Gilbank, Md Gladders, G Goldhaber, A Goobar, T Hattori, E Hsiao, Xiaosheng Huang, Y Ihara, K Kashikawa, B Koester, K Konishi, M Kowalski, C Lidman, L Lubin, J Meyers, T Morokuma, T Oda, N Panagia, S Perlmutter, M Postman, P Ripoche, P Rosati, D Rubin, Dj Schlegel, Al Spadafora, Sa Stanford, M Strovink, N Suzuki, N Takanashi, K Tokita, N Yasuda
The Hubble Space Telescope * Cluster Supernova Survey. Ii. The Type Ia Supernova Rate In High-Redshift Galaxy Clusters, K Barbary, G Aldering, R Amanullah, M Brodwin, N Connolly, Ks Dawson, M Doi, P Eisenhardt, L Faccioli, V Fadeyev, Hk Fakhouri, As Fruchter, D G. Gilbank, Md Gladders, G Goldhaber, A Goobar, T Hattori, E Hsiao, Xiaosheng Huang, Y Ihara, K Kashikawa, B Koester, K Konishi, M Kowalski, C Lidman, L Lubin, J Meyers, T Morokuma, T Oda, N Panagia, S Perlmutter, M Postman, P Ripoche, P Rosati, D Rubin, Dj Schlegel, Al Spadafora, Sa Stanford, M Strovink, N Suzuki, N Takanashi, K Tokita, N Yasuda
Physics and Astronomy
We report a measurement of the Type Ia supernova (SN Ia) rate in galaxy clusters at 0.9 < z < 1.46 from the Hubble Space Telescope Cluster Supernova Survey. This is the first cluster SN Ia rate measurement with detected z > 0.9 SNe. Finding 8 ± 1 cluster SNe Ia, we determine an SN Ia rate of 0.50+0.23 –0.19 (stat) +0.10 –0.09 (sys) h 2 70 SNuB (SNuB ≡ 10–12 SNe L –1 ☉, B yr–1). In units of stellar mass, this translates to 0.36+0.16 –0.13 (stat) +0.07 –0.06 (sys) h 2 70 SNuM (SNuM ≡ 10–12 SNe M –1 ☉ yr–1). This represents a …
Application Of Asymptotic Expansions For Maximum Likelihood Estimators' Errors To Gravitational Waves From Inspiraling Binary Systems: The Network Case, Salvatore Vitale, Michele Zanolin
Application Of Asymptotic Expansions For Maximum Likelihood Estimators' Errors To Gravitational Waves From Inspiraling Binary Systems: The Network Case, Salvatore Vitale, Michele Zanolin
Publications
This paper describes the most accurate analytical frequentist assessment to date of the uncertainties in the estimation of physical parameters from gravitational waves generated by nonspinning binary systems and Earth-based networks of laser interferometers. The paper quantifies how the accuracy in estimating the intrinsic parameters mostly depends on the network signal to noise ratio (SNR), but the resolution in the direction of arrival also strongly depends on the network geometry. We compare results for 6 different existing and possible global networks and two different choices of the parameter space. We show how the fraction of the sky where the one …
Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert A. Mcnees Iv, Robert Mann
Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert A. Mcnees Iv, Robert Mann
Physics: Faculty Publications and Other Works
A variational formulation is given for a theory of gravity coupled to a massive vector in four dimensions, with Asymptotically Lifshitz boundary conditions on the fields. For theories with critical exponent z=2 we obtain a well-defined variational principle by explicitly constructing two actions with local boundary counterterms. As part of our analysis we obtain solutions of these theories on a neighborhood of spatial infinity, study the asymptotic symmetries, and consider different definitions of the boundary stress tensor and associated charges. A constraint on the boundary data for the fields figures prominently in one of our formulations, and in that case …
Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert Mcnees, Robert Mann
Holographic Renormalization Of Asymptotically Lifshitz Spacetimes, Robert Mcnees, Robert Mann
Robert A McNees IV
A variational formulation is given for a theory of gravity coupled to a massive vector in four dimensions, with Asymptotically Lifshitz boundary conditions on the fields. For theories with critical exponent z = 2 we obtain a well-defined variational principle by explicitly constructing two actions with local boundary counterterms. As part of our analysis we obtain solutions of these theories on a neighborhood of spatial infinity, study the asymptotic symmetries, and consider different definitions of the boundary stress tensor and associated charges. A constraint on the boundary data for the fields figures prominently in one of our formulations, and in …
Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, Et Al
Veritas Observations Of The Unusual Extragalactic Transient Swift J164449.3+573451, P. T. Reynolds, Et Al
Physical Sciences Publications
We report on very high energy (>100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories. A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 × 10–12 erg cm–2 s–1 (99% confidence level). We also present time-resolved upper limits and use a …
The Variable Quiescent X-Ray Emission Of The Neutron Star Transient Xte J1701-462, Joel K. Fridriksson, Jeroen Homan, Rudy Wijnands, Edward M. Cackett, Diego Altamirano, Nathalie Degenaar, Edward F. Brown, Mariano Méndez, Tomaso M. Belloni
The Variable Quiescent X-Ray Emission Of The Neutron Star Transient Xte J1701-462, Joel K. Fridriksson, Jeroen Homan, Rudy Wijnands, Edward M. Cackett, Diego Altamirano, Nathalie Degenaar, Edward F. Brown, Mariano Méndez, Tomaso M. Belloni
Physics and Astronomy Faculty Research Publications
We present the results of continued monitoring of the quiescent neutron star low-mass X-ray binary XTE J1701-462 with Chandra and Swift. A new Chandra observation from 2010 October extends our tracking of the neutron star surface temperature from ≃ 800 days to ≃ 1160 days since the end of an exceptionally luminous 19 month outburst. This observation indicates that the neutron star crust may still be slowly cooling toward thermal equilibrium with the core; another observation further into quiescence is needed to verify this. The shape of the overall cooling curve is consistent with that of a broken power law, …
Quiescent X-Ray Variability From The Neutron Star Transient Aql X-1, E. M. Cackett, J. K. Fridriksson, J. Homan, J. M. Miller, R. Wijnands
Quiescent X-Ray Variability From The Neutron Star Transient Aql X-1, E. M. Cackett, J. K. Fridriksson, J. Homan, J. M. Miller, R. Wijnands
Physics and Astronomy Faculty Research Publications
A number of studies have revealed variability from neutron star low-mass X-ray binaries during quiescence. Such variability is not well characterized, or understood, but may be a common property that has been missed due to lack of multiple observations. One such source where variability has been observed is Aql X-1. Here, we analyse 14 Chandra and XMM-Newton observations of Aql X-1 in quiescence, covering a period of approximately 2 yr. There is clear variability between the epochs, with the most striking feature being a flare-like increase in the flux by a factor of 5. Spectral fitting is inconclusive as to …
High Gravitational Waveform Accuracy At Null Infinity, Maria Babiuc-Hamilton
High Gravitational Waveform Accuracy At Null Infinity, Maria Babiuc-Hamilton
Physics Faculty Research
The aim of Cauchy-characteristic extraction is to provide a standardized waveform extraction tool for the numerical relativity community. The new extraction tool contains major improvements and corrections to previous versions and displays convergence. The error introduced by CCE satisfies the time domain criteria required for advanced LIGO data analysis. The importance of accurate waveforms to the gravitational wave astronomy has created an urgency for tools like CCE. The source code has been released to the public and is available as part of the Einstein Toolkit. We welcome applications to a variety of generic Cauchy codes implementing Einstein Equations of General …
Interpretation Of The Arcade 2 Absolute Sky Brightness Measurement, M. Seiffert, D. J. Fixsen, A. Kogut, S. M. Levin, M. Limon, P. M. Lubin, P. Mirel, Jack Singal, T. Villela, E. Wollack, C. A. Wuensche
Interpretation Of The Arcade 2 Absolute Sky Brightness Measurement, M. Seiffert, D. J. Fixsen, A. Kogut, S. M. Levin, M. Limon, P. M. Lubin, P. Mirel, Jack Singal, T. Villela, E. Wollack, C. A. Wuensche
Physics Faculty Publications
We use absolutely calibrated data between 3 and 90 GHz from the 2006 balloon flight of the ARCADE 2 instrument, along with previous measurements at other frequencies, to constrain models of extragalactic emission. Such emission is a combination of the cosmic microwave background (CMB) monopole, Galactic foreground emission, the integrated contribution of radio emission from external galaxies, any spectral distortions present in the CMB, and any other extragalactic source. After removal of estimates of foreground emission from our own Galaxy, and an estimated contribution of external galaxies, we present fits to a combination of the flat-spectrum CMB and potential spectral …
Generation Of Coherent Structures After Cosmic Inflation, Marcelo Gleiser, Noah Graham, Nikitas Stamatopoulos
Generation Of Coherent Structures After Cosmic Inflation, Marcelo Gleiser, Noah Graham, Nikitas Stamatopoulos
Dartmouth Scholarship
We investigate the nonlinear dynamics of hybrid inflation models, which are characterized by two real scalar fields interacting quadratically. We start by solving numerically the coupled Klein-Gordon equations in static Minkowski spacetime, searching for possible coherent structures. We find long-lived, localized configurations, which we identify as a new kind of oscillon. We demonstrate that these two-field oscillons allow for “excited” states with much longer lifetimes than those found in previous studies of single-field oscillons. We then solve the coupled field equations in an expanding Friedmann-Robertson-Walker spacetime, finding that as the field responsible for inflating the Universe rolls down to oscillate …
An Analytical And Numerical Treatment Of Inclined Elliptical Orbits About A Kerr Black Hole, Peter G. Komorowski
An Analytical And Numerical Treatment Of Inclined Elliptical Orbits About A Kerr Black Hole, Peter G. Komorowski
Electronic Thesis and Dissertation Repository
Since its publication in 1915, Einstein's theory of general relativity has yielded significant results; they include: analytical solutions to the Einstein field equations; improved analysis of orbital dynamics; and the prediction of gravitational wave (GW) radiation. Gravitation is the weakest of the fundamental interactions; and theoretical models of GW generation and propagation show that its detection poses a significant technical challenge. Unlike the study of electromagnetic radiation, experiments within the laboratory are virtually impossible; so astronomical sources of GW, such as binary black hole systems, offer an alternative. But GW detection remains difficult. The matched filtering techniques used to discriminate …
Oral Presentation: The Universe In A Box, Jason Jaacks
Oral Presentation: The Universe In A Box, Jason Jaacks
Festival of Communities: UG Symposium (Posters)
When and how galaxies formed throughout the history of the Universe is one of the most fundamental questions of astronomy and astrophysics. As technology improves, astronomers are able to push the frontier of galaxy observation to a period when the Universe was less than 1 billion years old. This is when the first galaxies are beginning to form. However, beyond the limits of observational technology lies data fundamental to our complete understanding of these processes. Using state-of-the-art cosmological hydrodynamic computer codes combined with access to the nation’s largest and fastest supercomputers, we are able to simulate the formation and evolution …
Efficient Decomposition Of Cosmic Microwave Background Polarization Maps Into Pure E, Pure B, And Ambiguous Components., Emory F. Bunn
Efficient Decomposition Of Cosmic Microwave Background Polarization Maps Into Pure E, Pure B, And Ambiguous Components., Emory F. Bunn
Physics Faculty Publications
Separation of the B component of a cosmic microwave background (CMB) polarization map from the much larger E component is an essential step in CMB polarimetry. For a map with incomplete sky coverage, this separation is necessarily hampered by the presence of ambiguous modes which could be either E or B modes. I present an efficient pixel-space algorithm for removing the ambiguous modes and separating the map into pure E and B components. The method, which works for arbitrary geometries, does not involve generating a complete basis of such modes and scales the cube of the number of pixels on …
Further X-Ray Observations Of Exo 0748-676 In Quiescence: Evidence For A Cooling Neutron Star Crust, N. Degenaar, M. T. Wolff, P. S. Ray, K. S. Wood, J. Homan, W. H. G. Lewin, P. G. Jonker, E. M. Cackett, J. M. Miller, E. F. Brown, R. Wijnands
Further X-Ray Observations Of Exo 0748-676 In Quiescence: Evidence For A Cooling Neutron Star Crust, N. Degenaar, M. T. Wolff, P. S. Ray, K. S. Wood, J. Homan, W. H. G. Lewin, P. G. Jonker, E. M. Cackett, J. M. Miller, E. F. Brown, R. Wijnands
Physics and Astronomy Faculty Research Publications
In late 2008, the quasi-persistent neutron star X-ray transient and eclipsing binary EXO 0748-676 started a transition from outburst to quiescence, after it actively accreted for more than 24 yr. In a previous work, we discussed Chandra and Swift observations obtained during the first 5 months of this transition. Here, we report on further X-ray observations of EXO 0748-676, extending the quiescent monitoring to 1.6 yr. Chandra and XMM-Newton data reveal quiescent X-ray spectra composed of a soft, thermal component that is well fitted by a neutron star atmosphere model. An additional hard power-law tail is detected that changes non-monotonically …
A Fast X-Ray Disk Wind In The Transient Pulsar Igr J17480-2446 In Terzan 5, Jon M. Miller, Dipankar Maitra, Edward M. Cackett, Sudip Bhattacharyya, Tod E. Strohmayer
A Fast X-Ray Disk Wind In The Transient Pulsar Igr J17480-2446 In Terzan 5, Jon M. Miller, Dipankar Maitra, Edward M. Cackett, Sudip Bhattacharyya, Tod E. Strohmayer
Physics and Astronomy Faculty Research Publications
Accretion disk winds are revealed in Chandra gratings spectra of black holes. The winds are hot and highly ionized (typically composed of He-like and H-like charge states) and show modest blueshifts. Similar line spectra are sometimes seen in "dipping" low-mass X-ray binaries (LMXBs), which are likely viewed edge-on; however, that absorption is tied to structures in the outer disk, and blueshifts are not typically observed. Here, we report the detection of blueshifted He-like Fe XXV (3100 ± 400 km s-1) and H-like Fe XXVI (1000 ± 200 km s-1) absorption lines in a Chandra/HETG spectrum of …
Profiles In Science: Stephen Hawking, Kathleen A. Lehman
Profiles In Science: Stephen Hawking, Kathleen A. Lehman
University Libraries Faculty Publications and Presentations
While Stephen Hawking’s early academic career lacked focus, the development of motor neuron disease straining against his hopes for a fulfilling life pulled the young scientist’s work together. He has since become the world’s most famous scientist due, in part, to his strong belief that science should be accessible to the general public. Hawking has published frequently for the academic community but has also published for the lay reader. His life has been recorded and examined by several biographers. This paper gives an overview of Hawking’s early life, academic career, his academic and popular publications, as well as a few …
A Distinctive Disk-Jet Coupling In The Seyfert-1 Active Galactic Nucleus Ngc 4051, A. L. King, J. M. Miller, E. M. Cackett, A. C. Fabian, S. Markoff, M. A. Nowak, M. Rupen, K. Gültekin, M. T. Reynolds
A Distinctive Disk-Jet Coupling In The Seyfert-1 Active Galactic Nucleus Ngc 4051, A. L. King, J. M. Miller, E. M. Cackett, A. C. Fabian, S. Markoff, M. A. Nowak, M. Rupen, K. Gültekin, M. T. Reynolds
Physics and Astronomy Faculty Research Publications
We report on the results of a simultaneous monitoring campaign employing eight Chandra X-ray (0.5-10 keV) and six Very Large Array/Extended Very Large Array (8.4 GHz) radio observations of NGC 4051 over seven months. Evidence for compact jets is observed in the 8.4 GHz radio band; this builds on mounting evidence that jet production may be prevalent even in radio-quiet Seyferts. Assuming comparatively negligible local diffuse emission in the nucleus, the results also demonstrate an inverse correlation of L radio ∝ L -0.72±0.04 X-ray . If the A configuration is excluded in the case where diffuse emission plays a significant …
Multistate Observations Of The Galactic Black Hole Xte J1752-223: Evidence For An Intermediate Black Hole Spin, R. C. Reis, J. M. Miller, A. C. Fabian, E. M. Cackett, D. Maitra, C. S. Reynolds, M. Rupen, D. T. H. Steeghs, R. Wijnands
Multistate Observations Of The Galactic Black Hole Xte J1752-223: Evidence For An Intermediate Black Hole Spin, R. C. Reis, J. M. Miller, A. C. Fabian, E. M. Cackett, D. Maitra, C. S. Reynolds, M. Rupen, D. T. H. Steeghs, R. Wijnands
Physics and Astronomy Faculty Research Publications
The Galactic black hole candidate XTE J1752-223 was observed during the decay of its 2009 outburst with the Suzaku and XMM-Newton observatories. The observed spectra are consistent with the source being in the ‘intermediate’ and ‘low-hard’ states, respectively. The presence of a strong, relativistic iron emission line is clearly detected in both observations and the line profiles are found to be remarkably consistent and robust to a variety of continuum models. This strongly points to the compact object in XTE J1752-223 being a stellar mass black hole accretor and not a neutron star. Physically motivated and self-consistent reflection models for …
A Mathematical Exploration Of Low-Dimensional Black Holes, Abigail Lauren Stevens
A Mathematical Exploration Of Low-Dimensional Black Holes, Abigail Lauren Stevens
Senior Projects Spring 2011
In this paper we will be mathematically exploring low-dimensional gravitational physics and, more specifically, what it tells us about low-dimensional black holes and if there exists a Schwarzschild solution to Einstein's field equation in 2+1 dimensions. We will be starting with an existing solution in 3+1 dimensions, and then reconstructing the classical and relativistic arguments for 2+1 dimensions. Our conclusion is that in 2+1 dimensions, the Schwarzschild solution to Einstein's field equation is non-singular, and therefore it does not yield a black hole. While we still arrive at conic orbits, the relationship between Minkowski-like and Newtonian forces, energies, and geodesics …
A New Pulsar Instrumentation At The Allen Telescope Array And The Nancay Radio Telescope, G. Desvignes, William C. Barott, I. Cognard, P. Lespagnol, G. Theureau
A New Pulsar Instrumentation At The Allen Telescope Array And The Nancay Radio Telescope, G. Desvignes, William C. Barott, I. Cognard, P. Lespagnol, G. Theureau
Publications
In the prospect of the gravitational wave background detection with high precision pulsar timing, we recently installed a new coherent dedispersion backend at the Allen Telescope Array (ATA) and the Nançay Radio Telescope (NRT).
Condensation States And Landscaping With The Theory Of Abstraction, Subhajit Kumar Ganguly
Condensation States And Landscaping With The Theory Of Abstraction, Subhajit Kumar Ganguly
Subhajit Kumar Ganguly
The Abstraction theory is applied in landscaping. A collection of objects may be made to be vast or meager depending upon the scale of observations. This idea may be developed to unite the worlds of the great vastness of the universe and the minuteness of the sub-atomic realm. Keeping constant a scaling ratio for both worlds, these may actually be converted into two self-same representatives with respect to scaling. The Laws of Physical Transactions are made use of to study Bose-Einstein condensation. As the packing density of concerned constituents increase to a certain critical value, there may be evolution of …
Abstraction In Theory - Laws Of Physical Transactions, Subhajit Kumar Ganguly
Abstraction In Theory - Laws Of Physical Transactions, Subhajit Kumar Ganguly
Subhajit Kumar Ganguly
Considering transport or tendency of transport of physical entities from an initial to a final point,we come to a similar basis of understanding of various physical phenomena.The trajectory-behaviour of such transport represents the effect or field of influence.This way,we may explain cluster-formation in the universe,an expanding universe,etc.This may also lead to a similar basis for understanding the four non-contact forces of nature.Also,for different ranges of acceleration in the field formed in spacetime,we have different properties of matter interacting.This may explain the difference in ranges of the various forces.
Analyzing The Role Of Icts In The Tunisian And Egyptian Unrest From An Information Warfare Perspective, Brett Van Niekerk, Kiru Pillay, Manoj Maharaj
Analyzing The Role Of Icts In The Tunisian And Egyptian Unrest From An Information Warfare Perspective, Brett Van Niekerk, Kiru Pillay, Manoj Maharaj
Manoj Maharaj
In January 2011, the Tunisian government stepped down after weeks of protests; this was followed by unrest and protests in Egypt against the Egyptian government, leading also to the resignation of its president. Demonstrations in both countries were facilitated in some part by the online social media and related information and communications technologies that impacted the flow of information. The manner in which the information and communication technologies were employed suggests that the uprisings were a form of social information warfare. To provide an alternative understanding of the role of technology and information in the events that led to the …
The Information Warfare Lifecycle Model, Manoj Maharaj, Brett Van Nikerk
The Information Warfare Lifecycle Model, Manoj Maharaj, Brett Van Nikerk
Manoj Maharaj
No abstract provided.
Strategic Planning For Digital Convergence In South African Businesses, Manoj Maharaj, Kiru Pillay
Strategic Planning For Digital Convergence In South African Businesses, Manoj Maharaj, Kiru Pillay
Manoj Maharaj
No abstract provided.
Star Formation In M33 (Herm33es), C. Kramer, M. Boquien, J. Braine, C. Buchbender, Daniela Calzetti, P. Gratier, B. Mookerjea, M. Relaño, S. Verley
Star Formation In M33 (Herm33es), C. Kramer, M. Boquien, J. Braine, C. Buchbender, Daniela Calzetti, P. Gratier, B. Mookerjea, M. Relaño, S. Verley
Daniela Calzetti
Within the key project "Herschel M33 extended survey" (HerM33es), we are studying the physical and chemical processes driving star formation and galactic evolution in the nearby galaxy M33, combining the study of local conditions affecting individual star formation with properties only becoming apparent on global scales. Here, we present recent results obtained by the HerM33es team. Combining Spitzer and Herschel data ranging from 3.6um to 500um, along with HI, Halpha, and GALEX UV data, we have studied the dust at high spatial resolutions of 150pc, providing estimators of the total infrared (TIR) brightness and of the star formation rate. While …
Superluminal Neutrinos At Opera Confront Pion Decay Kinematics, Ramanath Cowsick, Shmuel Nussinov, Utpal Sarkar
Superluminal Neutrinos At Opera Confront Pion Decay Kinematics, Ramanath Cowsick, Shmuel Nussinov, Utpal Sarkar
Mathematics, Physics, and Computer Science Faculty Articles and Research
Violation of Lorentz invariance (VLI) has been suggested as an explanation of the superluminal velocities of muon neutrinos reported by OPERA. In this Letter, we show that the amount of VLI required to explain this result poses severe difficulties with the kinematics of the pion decay, extending its lifetime and reducing the momentum carried away by the neutrinos. We show that the OPERA experiment limits alpha = (upsilon(v) - c)/c < 4 x 10(-6). We then take recourse to cosmic-ray data on the spectrum of muons and neutrinos generated in Earth's atmosphere to provide a stronger bound on VLI: (upsilon - c)/c < 10(-12).
Flux Variation Of Cosmic Muons, N. Ramesh, M. Hawron, C. Martin, A. Bachri
Flux Variation Of Cosmic Muons, N. Ramesh, M. Hawron, C. Martin, A. Bachri
Journal of the Arkansas Academy of Science
In the current paper, we analyzed the variation of cosmic radiation flux with elevation, time of the year and ambient temperature with the help of a portable cosmic muon detector, the construction of which was completed by a team from Southern Arkansas University (SAU) at Lawrence Berkeley National Laboratory (LBNL). Cosmic muons and gamma rays traverse two synchronized scintillators connected to two photomultiplier tubes (PMT) via light guides, and generate electronic pulses which we counted using a Data Acquisition Board (DAQ). Because muons are the product of collisions between high-energy cosmic rays and atmospheric nuclei, and therefore shower onto earth, …
Children In God's House: Teaching Cosmology At A Nazarene University, Stephen Case
Children In God's House: Teaching Cosmology At A Nazarene University, Stephen Case
Faculty Scholarship – Geology
This is one of a collection of essays that attempts to articulate the common “center pole” around which Nazarene higher educators stand and the theological and pedagogical commitments that draw them together. It is one of a series of values documents for Nazarene educational institutions and was produced and reviewed by 51 faculty at 16 institutions from six countries. The title of the collection, Telos, comes from the Greek term used in the New Testament to address the perfect end, or destination, for which Christians are designed. This essay sets out how understanding and engaging with contemporary theories regarding the …