Results 31 to 40 of about 4,218 (183)
Key technologies of satellite communications aided by reconfigurable holographic surfaces
Dianxin kexue, 2022 Ultra-dense low earth orbit (LEO) satellite communication networks can overcome the scarcity of spectrum resources and the limited coverage of traditional terrestrial networks, and thus have the potential to provide high data rate services and global ...
Xinyuan HU +4 more
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The holographic principle for general backgrounds [PDF]
Classical and Quantum Gravity, 2000 We aim to establish the holographic principle as a universal law, rather than a property only of static systems and special space-times. Our covariant formalism yields an upper bound on entropy which applies to both open and closed surfaces, independently of shape or location.
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Probing Spacetime Foam with Extragalactic Sources of High-Energy Photons
Universe, 2022 Quantum fluctuations can endow spacetime with a foamy structure. In this review article, we discuss our various proposals to observationally constrain models of spacetime foam.
Y. Jack Ng, Eric S. Perlman
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The traveltime holographic principle [PDF]
Geophysical Journal International, 2014 Abstract Fermat's interferometric principle is used to compute interior transmission traveltimes τpq from exterior transmission traveltimes τsp and τsq. Here, the exterior traveltimes are computed for sources s on a boundary B that encloses a volume V of interior points p and q.
Huang, Yunsong, Schuster, Gerard T.
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The gravity dual of Rényi entropy
Nature Communications, 2016 The discovery that the entropy of black holes is given by their horizon area inspired the holographic principle and led to gauge-gravity duality. Here, the author shows that all Rényi entropies satisfy a similar area law in holographic theories and are ...
Xi Dong
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Entropy Bounds and Field Equations
Entropy, 2015 For general metric theories of gravity, we compare the approach that describes/derives the field equations of gravity as a thermodynamic identity with the one which looks at them from entropy bounds.
Alessandro Pesci
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Frontiers in Physics, 2020 In a recent note [1], I argued that the holographic origin of ordinary gravitational attraction is the quantum mechanical tendency for operators to grow under time evolution.
Leonard Susskind
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Bekenstein Bound and Non-Commutative Canonical Variables
Universe, 2022 A universal upper limit on the entropy contained in a localized quantum system of a given size and total energy is expressed by the so-called Bekenstein bound. In a previous paper [Buoninfante, L. et al.
Fabio Scardigli
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Holographic consequences of a no transmission principle
Physical Review D, 2016 Two quantum field theories whose Hilbert spaces do not overlap cannot transmit a signal to one another. From this simple principle, we deduce some highly nontrivial consequences for holographic quantum gravity. These include: (1) certain cosmological bounces are forbidden, (2) generic singularities inside black holes cannot be resolved, and (3 ...
Engelhardt, Netta, Horowitz, Gary T.
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Holographic Cavalieri principle as a universal relation between holographic complexity and holographic entanglement entropy [PDF]
International Journal of Modern Physics D, 2018 In this paper, we will propose a universal relation between the holographic complexity (dual to a volume in AdS) and the holographic entanglement entropy (dual to an area in anti-de Sitter (AdS)). We will explicitly demonstrate that our conjuncture holds for all metrics asymptotic to [Formula: see text], and then argue that such a relation should hold
Davood Momeni +2 more
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