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Related papers: Hyper-fast travel without negative energy

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I investigate the relationship between faster-than-light travel and weak-energy-condition violation, i.e., negative energy densities. In a general spacetime it is difficult to define faster-than-light travel, and I give an example of a…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Ken D. Olum

It recently has been demonstrated that signals conveyed by evanescent modes can travel faster than light. In this report some special features of signals are introduced and investigated, for instance the fundamental property that signals…

Classical Physics · Physics 2017-09-27 Guenter Nimtz

Photonic tunneling permits superluminal signal transmission. The principle of causality is not violated but the time duration between cause and effect can be shortened compared with an interaction exchange with velocity of light. This…

General Physics · Physics 2017-08-23 Günter Nimtz

Recent solutions to the Einstein Field Equations involving negative energy densities, i.e., matter violating the weak-energy-condition, have been obtained, namely traversable wormholes, the Alcubierre warp drive and the Krasnikov tube.…

General Relativity and Quantum Cosmology · Physics 2022-09-21 Francisco Lobo , Paulo Crawford

We exploit the analogy between tunnelling across a potential barrier and Aharonov's weak measurements to resolve the long standing paradox between the impossibility to exceed the speed of light and the seemingly 'superluminal' behaviur of…

Quantum Physics · Physics 2007-05-23 D. Sokolovski , A. Z. Msezane , V. R. Shaginyan

Warp drives in Einstein's general theory of relativity provide a unique mechanism for manned interstellar travel. It is well-known that the classical superluminal soliton spacetimes require negative energy densities, likely sourced by…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Shaun D. B. Fell , Lavinia Heisenberg

In light of the recent results from the OPERA collaboration, indicating that neutrinos can travel superluminally, I review a simple extra-dimensional strategy for accommodating such behavior; and I also explain why it is hard in this…

High Energy Physics - Theory · Physics 2015-05-30 Steven S. Gubser

An explanation for superluminal phenomena based on wave-particle duality of photons is suggested. A single photon may be regarded as a wave packet, whose spatial extension is its coherence volume. As a photon propagates as a wave train in…

Quantum Physics · Physics 2024-03-15 Hai-Long Zhao

The paper elucidates the physical basis of experimental results on superluminal signal velocity. It will be made plausible that superluminal signals do not violate the principle of causality but they can shorten the luminal vacuum time span…

Classical Physics · Physics 2017-09-27 G. Nimtz , A. Haibel

A universal relation has been established between the local energy transport velocity along the direction of propagation and the group velocity of scalar and vector-valued propagation-invariant spatiotemporally localized superluminal and…

Optics · Physics 2019-07-31 Peeter Saari , Ott Rebane , Ioannis Besieris

In the case of tunneling of relativistic particles, differently from the nonrelativistic case, a limit of "transparent" barrier can also lead to an apparent "superluminal" behavior when considering the phase time. In this limit, the…

Quantum Physics · Physics 2019-09-18 Massimo Germano

Various experiments have shown superluminal group and signal velocities recently. Experiments were essentials carried out with microwave tunnelling, with frustrated total internal reflection, and with gain-assisted anomalous dispersion.…

Classical Physics · Physics 2009-11-06 G. Nimtz , A. A. Stahlhofen , A. Haibel

Superfluidity, the ability of a fluid to move without dissipation, is one of the most spectacular manifestations of the quantum nature of matter. We explore here the possibility of superfluid motion of light. Controlling the speed of a…

Quantum Gases · Physics 2011-07-04 Patricio Leboeuf , Simon Moulieras

It is known that superluminal transmission of information and energy contradicts Einstein's relativity. Here we announce an unusual TOE called 'nature theory' in which impossible things become possible. We present the scheme of an apparatus…

Quantum Physics · Physics 2007-05-23 Zbigniew A. Nowacki

It is shown that the transferring of light signal faster-than-c can take place exclusively as the instantaneous quantum tunneling. Its extent (space size of instanton) must be inversely relative to lack of energy till nearest stable or…

Optics · Physics 2007-05-23 M. E. Perel'man

Motivated by increased interest in experiments in which light appears to propagate by tunnelling at superluminal velocity, the Lorentz invariant theory proposed by Partha Ghose to explain these surprising effects is revisited. This theory…

General Physics · Physics 2023-02-21 Luca Nanni

General relativity provides an appropriate framework for addressing the issue of sub- or superluminality as an apparent effect. Even though a massless particle travels on the light cone, its average velocity over a finite path measured by…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Dieter Lust , Marios Petropoulos

First, we extend the special relativity into the superluminal case and put forward a superluminal theory of kinematics, in which we show that the temporal coordinate need exchanging with one of the spatial coordinates in a superluminal…

General Physics · Physics 2009-07-22 Z. C. Tu , Z. Y. Wan

The question of whether it is possible or not to surpass the speed of light is already centennial. The special theory of relativity took the existence of a speed limit as a principle, the light postulate, which has proven to be enormously…

General Relativity and Quantum Cosmology · Physics 2010-01-29 Carlos Barceló , Stefano Finazzi , Stefano Liberati

We present a model for a vacuum-like effective medium composed of the absorbing and gain media under the special designed parameters. Within the linear response theory, we prove that any pulse signal (with or without a discontinuity)…

Optics · Physics 2008-10-21 Li-Gang Wang
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