Physical Sciences and Mathematics | Open Access Articles

A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Ian M. Anderson, Charles G. Torre

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We find a new homogeneous solution to the Einstein-Maxwell equations with a cos- mological term. The spacetime manifold is R × S3. The spacetime metric admits a simply transitive isometry group G = R × SU(2) and is Petrov type I. The spacetime is geodesically complete and globally hyperbolic. The electromagnetic field is non- null and non-inheriting: it is only invariant with respect to the SU(2) subgroup and is time-dependent in a stationary reference frame.

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Simultaneous In Situ Measurements Of Small-Scale Structures In Neutral, Plasma, And Atomic Oxygen Densities During The Wadis Sounding Rocket Project, Boris Strelnikov, Martin Eberhart, Martin Friedrich, Jonas Hedin, Mikhail Khaplanov, Gerd Baumgarten, Bifford P. Williams, Tristan Staszak, Heiner Asmus, Irina Strelnikova, Ralph Latteck, Mykhaylo Grygalashvyly, Franz-Josef Lübken, Josef Höffner, Raimund Wörl, Jörg Gumbel, Stefan Löhle, Stefanos Fasoulas, Markus Rapp, Aroh Barjatya, Michael J. Taylor, Pierre-Dominique Pautet

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In this paper we present an overview of measurements conducted during the WADIS-2 rocket campaign. We investigate the effect of small-scale processes like gravity waves and turbulence on the distribution of atomic oxygen and other species in the mesosphere–lower thermosphere (MLT) region. Our analysis suggests that density fluctuations of atomic oxygen are coupled to fluctuations of other constituents, i.e., plasma and neutrals. Our measurements show that all measured quantities, including winds, densities, and temperatures, reveal signatures of both waves and turbulence. We show observations of gravity wave saturation and breakdown together with simultaneous measurements of generated turbulence. Atomic oxygen inside …

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Large‐Amplitude Mountain Waves In The Mesosphere Observed On 21 June 2014 During Deepwave: 1.Wave Development, Scales, Momentum Fluxes, And Environmental Sensitivity, Michael J. Taylor, Pierre-Dominique Pautet, David C. Fritts, Bernd Kaifler, Steven M. Smith, Yucheng Zhao, Neal R. Criddle, Pattilyn Mclaughlin, William R. Pendleton Jr., Michael P. Mccarthy, Gonzalo Hernandez, Stephen D. Eckermann, James Doyle, Markus Rapp, Ben Liley, James M. Russell Iii

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A remarkable, large‐amplitude, mountain wave (MW) breaking event was observed on the night of 21 June 2014 by ground‐based optical instruments operated on the New Zealand South Island during the Deep Propagating Gravity Wave Experiment (DEEPWAVE). Concurrent measurements of the MW structures, amplitudes, and background environment were made using an Advanced Mesospheric Temperature Mapper, a Rayleigh Lidar, an All‐Sky Imager, and a Fabry‐Perot Interferometer. The MW event was observed primarily in the OH airglow emission layer at an altitude of ~82 km, over an ~2‐hr interval (~10:30–12:30 UT), during strong eastward winds at the OH altitude and above, which weakened …

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Regional Distribution Of Mesospheric Small‐Scale Gravity Waves During Deepwave, Pierre-Dominique Pautet, Michael J. Taylor, S. D. Eckermann, Neal R. Criddle

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The Deep Propagating Gravity Wave Experiment project took place in June and July 2014 in New Zealand. Its overarching goal was to study gravity waves (GWs) as they propagate from the ground up to ~100 km, with a large number of ground‐based, airborne, and satellite instruments, combined with numerical forecast models. A suite of three mesospheric airglow imagers operated onboard the NSF Gulfstream V (GV) aircraft during 25 nighttime flights, recording the GW activity at OH altitude over a large region (>7,000,000 km²). Analysis of this data set reveals the distribution of the small‐scale GW mean power …

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Spacetime Groups, Ian M. Anderson, Charles G. Torre

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A spacetime group is a connected 4-dimensional Lie group G endowed with a left invariant Lorentz metric h and such that the connected component of the isometry group of h is G itself. The Newman-Penrose formalism is used to give an algebraic classification of spacetime groups, that is, we determine a complete list of inequivalent spacetime Lie algebras, which are pairs (g,η), with g being a 4-dimensional Lie algebra and η being a Lorentzian inner product on g. A full analysis of the equivalence problem for spacetime Lie algebras is given which leads to a completely algorithmic solution to the …

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How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan J. Sojka, Robert W. Schunk

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One of the most important input fields for an ionospheric model is the horizontal neutral wind. The primary mechanism by which the neutral wind affects ionospheric densities is the inducement of an upward or downward ion drift along the magnetic field lines; this affects the rate at which ions are lost through recombination. The magnitude of this effect depends upon the dip angle of the magnetic field; for this reason, the impact of the neutral wind is somewhat less in polar regions than at mid-latitudes. It is unfortunate that observations of the neutral wind are relatively scarce, as compared for …

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Full-Text Articles in Physical Sciences and Mathematics

A New Non-Inheriting Homogeneous Solution Of The Einstein-Maxwell Equations With Cosmological Term, Ian M. Anderson, Charles G. Torre

Publications

Publications

Publications

Regional Distribution Of Mesospheric Small‐Scale Gravity Waves During Deepwave, Pierre-Dominique Pautet, Michael J. Taylor, S. D. Eckermann, Neal R. Criddle

Publications

Spacetime Groups, Ian M. Anderson, Charles G. Torre

Publications

How Uncertainty In The Neutral Wind Limits The Accuracy Of Ionospheric Modeling And Forecasting, Michael David, Jan J. Sojka, Robert W. Schunk

Publications