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The quark model and the parton model are known to be two different manifestations of the same covariant entity. However, the interaction amplitudes of partons are incoherent while they are coherent in the quark model. According to Feynman,…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. Han , Y. S. Kim

We investigate experimentally the effects of light assisted collisions on the coherence between momentum states in Bose-Einstein condensates. The onset of superradiant Rayleigh scattering serves as a sensitive monitor for matter wave…

The notion of a macroscopic quantum state must be pinned down in order to assess how well experiments probe the large-scale limits of quantum mechanics. However, the issue of quantifying so-called quantum macroscopicity is fraught with…

Quantum Physics · Physics 2025-03-12 Benjamin Yadin , Matteo Fadel

The coherent evolution of two atomic qubits mediated by a set of bosonic field modes is investigated. By assuming a specific encoding of the quantum states in the internal levels of the two atoms we show that entangling quantum gates can be…

Quantum Physics · Physics 2015-05-18 Sai-Yun Ye , Zhen-Biao Yang , Shi-Biao Zheng , Alessio Serafini

Recent work has shown how single-particle entangled states are transformed when boosted in relativistic frames for certain restricted geometries. Here we extend that work to consider completely general inertial boosts. We then apply our…

Quantum Physics · Physics 2015-05-30 Veiko Palge , Vlatko Vedral , Jacob A. Dunningham

Quantum coherence is the basic concept of superposition of quantum states and plays an important role in quantum metrology. We show how a pair of uniformly accelerated observers with a local two-mode Gaussian quantum state affects the…

Quantum Physics · Physics 2023-04-18 Xiaolong Gong , Yue Fang , Tonghua Liu , Shuo Cao

Recent studies have increasingly focused on the effect of relativistic motion on quantum coherence. Prior research predominantly examined the influence of relative motion on basis-dependent quantum coherence, underscoring its susceptibility…

Light wave-packets propagating from the Earth to satellites will be deformed by the curved background spacetime of the Earth, thus influencing the quantum state of light. We show that Gaussian coherence of photon pairs, which are initially…

Quantum Physics · Physics 2019-10-11 Tonghua Liu , Shumin Wu , Shuo Cao

In neutrino physics, it is sometimes assumed that all wave packets must transform covariantly as Lorentz vectors. We show in a simple example that even if the initial conditions of a wave packet are covariant, then evolution in a…

High Energy Physics - Phenomenology · Physics 2020-02-14 Emilio Ciuffoli , Jarah Evslin , Hosam Mohammed

In relativity, there is no absolute notion of simultaneity, because two clocks that are in different places can always be desynchronized by a Lorentz boost. Here, we explore the implications of this effect for the quantum theory of unstable…

General Physics · Physics 2022-10-24 L. Gavassino , F. Giacosa

In this paper we describe the transformation properties of quantum entanglement encoded in a pair of spin 1/2 particles described via Dirac bispinors. Due to the intrinsic parity-spin internal structure of the bispinors, the joint state is…

Quantum Physics · Physics 2018-10-04 Victor A. S. V. Bittencourt , Alex E. Bernardini , Massimo Blasone

We examine the behavior of quadrature coherence under the measurement of the same field quadrature. This is carried out with the help of a beam splitter, which implies the contribution of an auxiliary field state impinging at the other…

Quantum Physics · Physics 2026-01-30 Lucía Álvarez , Alfredo Luis

The quite different behaviors exhibited by microscopic and macroscopic systems with respect to quantum interferences suggest the existence of a borderline beyond which quantum systems loose their coherences and can be described classically.…

General Relativity and Quantum Cosmology · Physics 2008-06-17 Marc-Thierry Jaekel , Brahim Lamine , Astrid Lambrecht , Serge Reynaud , Paulo Maia Neto

Does the measurement of a quantum system necessarily break Lorentz invariance? We present a simple model of a detector that measures the spacetime localization of a relativistic particle in a Lorentz invariant manner. The detector does not…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Donald Marolf , Carlo Rovelli

Canonical quantisation of rigid particles is considered paying special attention to the restriction on phase space due to causal propagation. A mixed Lorentz-gravitational anomaly is found in the commutator of Lorentz boosts with world-line…

High Energy Physics - Theory · Physics 2009-10-22 Jan Govaerts

The evolution of the quantum wave packet describing an atom trapped in the surface-tip junction of the scanning tunneling microscope is investigated by using the time-dependent Schroedinger equation, and by a quasi-classical Hamiltonian…

Quantum Physics · Physics 2008-02-21 M. Grigorescu

A brief review is given of the present state of an approach to consistency between basic quantum mechanics and a unique macroscopic reality, with no assumption of branching in the state of the universe. The main new idea consists in the…

Quantum Physics · Physics 2013-02-08 Roland Omnes

Effect of Lorentz transformation on some properties of multi-qubit systems is investigated. It is shown that, properties like, the fidelity and entanglement decay as the Wigner's angles increase, but can be improved, if all the transformed…

Quantum Physics · Physics 2015-02-09 N. Metwally

In this paper we investigate the robustness of the quantum correlations against the environment effects in various opto-mechanical bipartite systems. For two spatially separated opto-mechanical cavities, we give analytical formula for the…

Quantum Physics · Physics 2015-12-09 J. El Qars , M. Daoud , Ahl Laamara

Measurements can be considered as a genuine example of processes that crush quantum coherence. In the case of an observable with degeneracy, the formulations of L\"{u}ders and von Neumann are known. These pictures postulate the two…

Quantum Physics · Physics 2019-04-23 Alexey E. Rastegin