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Related papers: A Bit Rate Bound on Superluminal Communication

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It has been recently suggested that the dynamics of a quantum spin system may provide a natural mechanism for transporting quantum information. We show that one dimensional rings of qubits with fixed (time-independent) interactions,…

Quantum Physics · Physics 2007-05-23 Tobias J. Osborne , Noah Linden

A bound on the maximum information transmission rate through a cascade of Gaussian links is presented. The network model consists of a source node attempting to send a message drawn from a finite alphabet to a sink, through a cascade of…

Information Theory · Computer Science 2013-01-29 Ramanan Subramanian , Badri Vellambi , Ingmar Land

We theoretically investigate the electron transport properties for a semiconductor quantum wire containing a single finite-size attractive impurity under an external terahertz electromagnetic field illumination in the ballistic limit.…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Guanghui Zhou , Yuan Li , Fang Cheng , Wenfu Liao

We study theoretically and numerically the conditions required for the appearance of a superradiance transition in graphene. The electron properties of graphene are described in the single $p_z$-orbital tight-binding approximation, in which…

Superconducting quantum circuits, fabricated with multiple layers, are proposed to implement perfect quantum state transfer between nodes of a hypercube network. For tunable devices such as the phase qubit, each node can transmit quantum…

Quantum Physics · Physics 2009-11-13 Frederick W. Strauch , Carl J. Williams

There have been several experiments which hint at evidence for superluminal transport of electromagnetic energy through a material slab. On the theoretical side, it has appeared evident that acausal signals are indeed possible in quantum…

Quantum Physics · Physics 2009-10-31 V. Kidambi , A. Widom

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 discuss some properties of Lorentz invariant theories which allow for superluminal motion. We show that, if signals are always sent forward in time, closed curves along which signals propagate can be formed. This leads to problems with…

Astrophysics · Physics 2007-06-28 Camille Bonvin , Chiara Caprini , Ruth Durrer

In this paper the fields generated by an electric dipole and a gravitational quadrapole are shown to propagate superluminally in the nearfield of the source and reduce to the speed of light as the fields propagate into the farfield. A…

General Physics · Physics 2007-05-23 William D. Walker

We consider the well-studied radio network model: a synchronous model with a graph G=(V,E) with |V|=n where in each round, each node either transmits a packet, with length B=Omega(log n) bits, or listens. Each node receives a packet iff it…

Data Structures and Algorithms · Computer Science 2013-02-04 Mohsen Ghaffari , Bernhard Haeupler , Majid Khabbazian

We theoretically investigate the transmission of electromagnetic radiation through a metal plate with a zero-$\epsilon$ metamaterial slit, where the permittivity tends towards zero over a given bandwidth. Our analytic results demonstrate…

Optics · Physics 2008-09-15 Klaus Halterman , Simin Feng

Electronic transport is theoretically investigated in laterally confined semiconductor superlattices using the formalism of non-equilibrium Green's functions. The transport properties are calculated for nanowire superlattices of varying…

Mesoscale and Nanoscale Physics · Physics 2014-04-25 Thomas Grange

We revise the 'no-signaling' condition for the supraluminal communication between two spatially separated finite quantum systems of arbitrary dimensions, thus generalizing a similar preceding approach for two-qubits: non-linear evolution…

Quantum Physics · Physics 2007-05-23 M. Ferrero , D. Salgado , J. L. Sanchez-Gomez

As an unusual type of anomalous diffusion behavior, (transient) superballistic transport is not well understood but it has been experimentally observed recently. We here calculate the white noise effect (in Markov approximation) on the…

Quantum Physics · Physics 2017-03-08 E. Gholami , Z. Mohammaddost-Lashkami

This paper is concerned with the propagating speeds of transition fronts in $R^N$ for spatially periodic bistable reaction-diffusion equations. The notion of transition fronts generalizes the standard notions of traveling fronts. Under the…

Analysis of PDEs · Mathematics 2017-06-16 Hongjun Guo

We show that optical tachyonic dispersion corresponding to superluminal (faster than-light) group velocities characterizes parametrically amplifying media. The turn-on of parametric amplification in finite media, followed by illumination by…

Quantum Physics · Physics 2011-04-15 G. Kurizki , A. E. Kozhekin , A. G. Kofman , M. Blaauboer

In a recent paper, A.Y. Shiekh has discussed an experimental set-up which, in his opinion, should make possible faster-than-light communication using the collapse of the quantum wave function. Contrary to the many proposals which have been…

Quantum Physics · Physics 2009-11-13 A. Bassi , G. C. Ghirardi

We demonstrate conditional entanglement swapping, i.e. teleportation of entanglement, between time-bin qubits at the telecommunication wavelength of 1536.4 nm with high fidelity of 87\%. Our system is deployable, utilizing modular,…

Identifying the physical grounds distinguishing quantum theory from broader probabilistic frameworks remains an open challenge. Communication-based proposals -- most notably the principles of impossibility of superluminal signaling and…

The photonic temporal degree of freedom is one of the most promising platforms for quantum communication over fiber networks and free-space channels. In particular, time-bin states of photons are robust to environmental disturbances,…

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