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Full-Text Articles in Physical Sciences and Mathematics
Hemispherical Shifted Symmetry In Polar Cap Patch Occurrence: A Survey Of Gps Tec Maps From 2015–2018, Michael David, Jan Josef Sojka, Robert W. Schunk, Anthea J. Coster
Hemispherical Shifted Symmetry In Polar Cap Patch Occurrence: A Survey Of Gps Tec Maps From 2015–2018, Michael David, Jan Josef Sojka, Robert W. Schunk, Anthea J. Coster
All Physics Faculty Presentations
Much theoretical and observational work has been devoted to studying the occurrence of F region polar cap patches in the Northern Hemisphere; considerably less work has been applied to the Southern Hemisphere. In recent years, the Madrigal database of mappings of total electron content (TEC) has improved in Southern Hemisphere coverage, to the point that we can now carry out a study of patch frequency and occurrence. We find that Southern Hemisphere patch occurrence is very similar to that of the Northern Hemisphere with a half‐year offset, plus an offset in universal time of approximately 12 hr. This is further …
A Near Horizon Extreme Binary Black Hole Geometry, Jacob Ciafre, Maria J. Rodriguez
A Near Horizon Extreme Binary Black Hole Geometry, Jacob Ciafre, Maria J. Rodriguez
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A new solution of four-dimensional vacuum General Relativity is presented. It describes the near horizon region of the extreme (maximally spinning) binary black hole system with two identical extreme Kerr black holes held in equilibrium by a massless strut. This is the first example of a non-supersymmetric, near horizon extreme binary black hole geometry of two uncharged black holes. The black holes are co-rotating, their relative distance is fixed, and the solution is uniquely specified by the mass. Asymptotically, the geometry corresponds to the near horizon extreme Kerr (NHEK) black hole. The binary extreme system has finite entropy.
Blandford-Znajek Process In Vacuo And Its Holographic Dual, Ted Jacobson, Maria J. Rodriguez
Blandford-Znajek Process In Vacuo And Its Holographic Dual, Ted Jacobson, Maria J. Rodriguez
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Blandford and Znajek discovered a process by which a spinning black hole can transfer rotational energy to a plasma, offering a mechanism for energy and jet emissions from quasars. Here we describe a version of this mechanism that operates with only vacuum electromagnetic fields outside the black hole. The setting, which is not astrophysically realistic, involves either a cylindrical black hole or one that lives in 2+1 spacetime dimensions, and the field is given in simple, closed form for a wide class of metrics. For asymptotically anti–de Sitter black holes in 2+1 dimensions, the holographic dual of this mechanism is …