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Cosmology, Relativity, and Gravity Commons™

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2004

Articles 1 - 8 of 8

Full-Text Articles in Cosmology, Relativity, and Gravity

Dark-Matter Electric And Magnetic Dipole Moments, Kris Sigurdson, Michael Doran, Andriy Kurylov, Robert R. Caldwell, Marc Kamionkowski Oct 2004

Dark-Matter Electric And Magnetic Dipole Moments, Kris Sigurdson, Michael Doran, Andriy Kurylov, Robert R. Caldwell, Marc Kamionkowski

Dartmouth Scholarship

We consider the consequences of a neutral dark-matter particle with a nonzero electric and/or magnetic dipole moment. Theoretical constraints, as well as constraints from direct searches, precision tests of the standard-model, the cosmic microwave background and matter power spectra, and cosmic gamma rays, are included. We find that a relatively light particle with mass between an MeV and a few GeV and an electric or magnetic dipole as large as ∼3×10−16e  cm (roughly 1.6×10−5μB) satisfies all experimental and observational bounds. Some of the remaining parameter space may be probed with forthcoming more sensitive direct searches and with the Gamma-Ray Large …

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Book Review: The Edge Of Infinity: Supermassive Black Holes In The Universe, T. D. Oswalt Jun 2004

Book Review: The Edge Of Infinity: Supermassive Black Holes In The Universe, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of The Edge of Infinity : Supermassive Black Holes in the Universe by Fulvio Melia. Cambridge, 2003 148p, 0-521-81405-7 $30.00.

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Book Review: The Big Bang: A View From The 21st Century, T. D. Oswalt Feb 2004

Book Review: The Big Bang: A View From The 21st Century, T. D. Oswalt

Publications

This document is Dr. Oswalt’s review of The Big Bang : a View from the 21st Century by David M. Harland. Springer/Praxis, 2003 262p, 1-85233-713-3 $39.95.

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Senior Thesis Work, Corey Jansen Jan 2004

Senior Thesis Work, Corey Jansen

Presidential Scholars Theses (1990 – 2006)

In closing, it is important to remember, as stated earlier, that no one can prove exactly what it was that the authors of Genesis were trying to get across to us. It is valid to note, however, that the stories they were trying to get across were intended for and more properly understood by the people at that time and place. While they form the basis of many of our beliefs in Christianity, they weren't written with the realization that thousands of years later there would be great scientific discoveries that would teach us more about the world and about …

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The Faith Factor: New Testament Cosmology In Its Historical Context, Keith A. Burton Jan 2004

The Faith Factor: New Testament Cosmology In Its Historical Context, Keith A. Burton

Journal of the Adventist Theological Society

No abstract provided.

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Lisa Time-Delay Interferometry Zero-Signal Solution: Geometrical Properties, Massimo Tinto, Shane L. Larson Jan 2004

Lisa Time-Delay Interferometry Zero-Signal Solution: Geometrical Properties, Massimo Tinto, Shane L. Larson

All Physics Faculty Publications

Time-delay interferometry (TDI) is the data processing technique needed for generating interferometric combinations of data measured by the multiple Doppler readouts available onboard the three Laser Interferometer Space Antenna (LISA) spacecraft. Within the space of all possible interferometric combinations TDI can generate, we have derived a specific combination that has zero response to the gravitational wave signal, and called it the zero-signal solution (ZSS). This is a two-parameter family of linear combinations of the generators of the TDI space, and its response to a gravitational wave becomes null when these two parameters coincide with the values of the angles of …

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Novel N-Body Orbits For Constrained Potentials Including The Unusual Figure Eight Three Body Orbit, Jan M. Dudzik Jan 2004

Novel N-Body Orbits For Constrained Potentials Including The Unusual Figure Eight Three Body Orbit, Jan M. Dudzik

Masters Theses

Recently new n-body planar orbits have been discovered which are known as choreographies. These orbits correspond to small n, generally n<20, and exhibit unexpected patterns with respect to given initial conditions. Here we shall examine numerical solutions to the three-body problem and the restricted three-body problem for three body potentials that are the sum of three two-body potentials. Then for an everywhere attractive three body potential with non-collinear and collision-less orbits with a strictly monotone decreasing potential function there exist bound states that are not chaotic that are choreographies. For the right initial conditions these orbits can be mapped numerically and visualized. We will display a number of these cases corresponding to the three body problem, restricted three body problem, the chaotic restricted three body problem and the new figure eight bound state choreography for the Kazalov potential orbits to exhibit some of their special features and to take note of a number of open questions dealing with simple orbital problems.

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Riemann Tensor Of The Ambient Universe, The Dilaton, And Newton’S Constant, Rossen Ivanov, Emil Prodanov Jan 2004

Riemann Tensor Of The Ambient Universe, The Dilaton, And Newton’S Constant, Rossen Ivanov, Emil Prodanov

Articles

We investigate a four-dimensional world, embedded into a five-dimensional spacetime, and find the five-dimensional Riemann tensor via generalisation of the Gauss (--Codacci) equations. We then derive the generalised equations of the four-dimensional world and also show that the square of the dilaton field is equal to the Newton's constant. We find plausable constant and non-constant solutions for the dilaton. Comment: 5 pages, revtex

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