Results 41 to 50 of about 2,199,245 (317)
Null Energy Condition in Dynamic Wormholes [PDF]
Physical Review Letters, 1998 4 pages in RevTex; some textual changes made, references added and some key definitions ...
Hochberg, David, Visser, Matt
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Abnormal thickness-dependent magneto-transport properties of vdW magnetic semiconductor Cr2Si2Te6
npj 2D Materials and Applications, 2023 Cr2Si2Te6 (CST) is a van der Waals (vdW) ferromagnetic semiconductor. The unique spin model and temperature-dependent magnetic ordering of CST provide opportunities for the next generation of two-dimensional (2D) spintronic devices.
Yun Li +6 more
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A Proposal of a Regular Black Hole Satisfying the Weak Energy Condition
Galaxies, 2018 We discuss a black hole generated by some matter fluid, whose stress-energy tensor is known. We show that it is regular and that it satisfies the Weak Energy Condition (WEC) and the null energy condition (NEC).
Stefano Chinaglia
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Stable Wormholes in the Background of an Exponential f(R) Gravity
Universe, 2020 The current paper is devoted to investigating wormhole solutions with an exponential gravity model in the background of f ( R ) theory. Spherically symmetric static spacetime geometry is chosen to explore wormhole solutions with anisotropic fluid
Ghulam Mustafa +2 more
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Scientific Reports, 2023 The structural stability and internal properties of hybrid organic–inorganic perovskites (HOIPs) have been widely investigated over the past few years. The interplay between organic cations and inorganic framework is one of the prominent features. Herein
Ardimas +5 more
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Criteria for energy conditions
Classical and Quantum Gravity, 2022 Abstract In model building studies, it is important to check the energy conditions for the corresponding energy–momentum tensor determined by the gravitational field equations in order to single out physically reasonable models. In this process, one often encounters a situation where the energy–momentum tensor has one off-diagonal ‘space–
Hideki Maeda, Tomohiro Harada
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Solar energy under cold climatic conditions: A review
, 2017 Solar energy has seen tremendous development in recent years towards fulfilling the energy requirements of our planet. This paper presents an extensive review of solar-energy-based technologies and research work conducted under cold climatic conditions ...
Mussard, Maxime, Maxime, Mussard
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Nature Communications, 2023 Kagome metals continue to attract interest due to the coexistence of electronic correlations and band topology. Here the authors use proton gating to modulate disorder and carrier density in CsV3Sb5 nanoflakes, and show its effect on superconductivity ...
Guolin Zheng +13 more
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Operating conditions of batteries in off-grid renewable energy systems
, 2022 S.1409-1425Operating conditions in off-grid renewable energy systems (RES) vary significantly in different applications and locations. To describe RES and the operating conditions of their components it is useful to define categories of similar operating
Svoboda, V. +20 more
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Traversable Kaluza–Klein Wormholes?
UniverseVarious authors have suggested that Kaluza–Klein variants of traversable wormholes might to some extent ameliorate the defocussing properties (the curvature condition violations, and implied energy condition violations) inherent in positing the existence
Christopher Simmonds, Matt Visser
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