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Related papers: Positivity in Amplitudes and Quantum Entanglement

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The problem of entanglement produced by an arbitrary operator is formulated and a related measure of entanglement production is introduced. This measure of entanglement production satisfies all properties natural for such a characteristic.…

Quantum Physics · Physics 2009-11-10 V. I. Yukalov

The ability to create and harness entanglement is crucial to the fields of quantum sensing and simulation, and ultracold atom-cavity systems offer pristine platforms for this undertaking. Here, we present a method for creating and…

X states are a broad class of two-qubit density matrices that generalize many states of interest in the literature. In this work, we give a comprehensive account of various quantum properties of these states, such as entanglement,…

Quantum Physics · Physics 2015-06-05 Nicolás Quesada , Asma Al-Qasimi , Daniel F. V. James

Quantum scrambling describes the spreading of local information into many degrees of freedom in quantum systems. This provides the conceptual connection among diverse phenomena ranging from thermalizing quantum dynamics to models of black…

We use open quantum system techniques to construct one-parameter semigroups of positive maps and apply them to study the entanglement properties of a class of 16-dimensional density matrices, representing states of a 4x4 bipartite system.

Quantum Physics · Physics 2007-05-23 Fabio Benatti , Roberto Floreanini , Marco Piani

We formulate an S-matrix theory in which localisation effects of the particle interactions involved in a scattering process are consistently taken into account. In the limit of an infinite spread of all interactions, the S-matrix assumes…

High Energy Physics - Theory · Physics 2023-08-16 Dimitrios Karamitros , Apostolos Pilaftsis

We explore the role of entanglement in adiabatic quantum optimization by performing approximate simulations of the real-time evolution of a quantum system while limiting the amount of entanglement. To classically simulate the time evolution…

Disordered Systems and Neural Networks · Physics 2015-01-29 Bela Bauer , Lei Wang , Iztok Pižorn , Matthias Troyer

We consider a massive, neutral, scalar field theory of mass $m_0$ in a five dimensional flat spacetime. Subsequently, one spatial dimension is compactified on a circle, $S^1$, ofradius $R$. The resulting theory is defined in the manifold,…

High Energy Physics - Theory · Physics 2019-06-26 Jnanadeva Maharana

We report on the quantification of entanglement by means of entanglement measures on a four- and a six- qubit cluster state realized by using photons entangled both in polarization and linear momentum. This paper also addresss the question…

Quantum Physics · Physics 2011-03-23 H. Wunderlich , G. Vallone , P. Mataloni , M. B. Plenio

For a bi-partite quantum system defined in a finite dimensional Hilbert space we investigate in what sense entanglement change and interactions imply each other. For this purpose we introduce an entanglement operator, which is then shown to…

Quantum Physics · Physics 2009-11-07 J. Gemmer , G. Mahler

We investigate the entangling capability of passive optical elements, both qualitatively and quantitatively. We present a general necessary and sufficient condition for the possibility of creating distillable entanglement in an arbitrary…

Quantum Physics · Physics 2009-11-07 M. M. Wolf , J. Eisert , M. B. Plenio

Einstein, Podolsky, and Rosen discussed their paradox in terms of measuring the positions or momenta of two particles. These degrees of freedom can become entangled upon scattering, but how much entanglement can be created in this process?…

Quantum Physics · Physics 2025-12-23 Yimeng Wang , Christiane P. Koch

We derive new positivity bounds for scattering amplitudes in theories with a massless graviton in the spectrum in four spacetime dimensions, of relevance for the weak gravity conjecture and modified gravity theories. The bounds imply that…

High Energy Physics - Theory · Physics 2019-12-25 Brando Bellazzini , Matthew Lewandowski , Javi Serra

We experimentally study cosmological particle production in a two-dimensional Bose-Einstein condensate, whose density excitations map to an analog cosmology. The expansion of spacetime is realized with tunable interactions. The particle…

We consider the quantum entanglement of the electronic and vibrational degrees of freedom in molecules with a tendency towards double welled potentials using model coupled harmonic diabatic potential-energy surfaces. The von Neumann entropy…

Quantum Physics · Physics 2012-02-24 Laura K. McKemmish , Ross H. McKenzie , Noel S. Hush , Jeffrey R. Reimers

We present universal relations between entanglement entropy, which quantifies the quantum correlation between subsystems, and the elastic cross section, which is the primary observable for high energy particle scattering, by employing a…

High Energy Physics - Theory · Physics 2024-10-31 Ian Low , Zhewei Yin

Quantum entanglement manifests as a distinctive correlation between particles that transcends classical boundaries when their quantum states cannot be described independently. On the other hand, as quantum systems interact with their…

Quantum Physics · Physics 2025-08-21 Samuel Marquez Gonzalez

We investigate multipartite entanglement dynamics in disordered spin-1/2 lattice models exhibiting a transition from integrability to quantum chaos. Borrowing from the recently introduced generalized entanglement framework, we construct…

Quantum Physics · Physics 2009-11-11 Simone Montangero , Lorenza Viola

Motivated by recent discussions of entanglement in the context of high energy scattering, we consider the relation between the entanglement entropy of a highly excited state of a quantum system and the classical entanglement entropy of the…

Quantum Physics · Physics 2023-01-18 Haowu Duan , Alex Kovner , Vladimir V. Skokov

We compare the scattering amplitude resulting from the several quasipotential equations for scalar particles. We consider the Blankenbecler-Sugar, Spectator, Thompson, Erkelenz-Holinde and Equal-Time equations, which were solved numerically…

Nuclear Theory · Physics 2009-11-07 G. Ramalho , A. Arriaga , M. T. Peña