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Related papers: Observers and Locality in Everett Quantum Field Th…

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We model measuring processes of a single spin-1/2 object and of a pair of spin-1/2 objects in the EPR-Bohm state by systems of differential equations. Our model is a local model with hidden-variables of the EPR-Bohm Gedankenexperiment.…

Quantum Physics · Physics 2016-09-08 S. Uchiyama

Conventionally, one interprets the correlations observed in Einstein-Podolsky-Rosen experiments by Bell's inequalities and quantum nonlocality. We show, in this paper, that identical correlations arise, if the phase relations of…

Quantum Physics · Physics 2007-05-23 W. A. Hofer

In recent years, the presence of local potentials has significantly enriched and diversified the entanglement patterns in monitored free fermion systems. In our approach, we employ the stochastic Schr\"odinger equation to simulate a…

Quantum Physics · Physics 2026-02-09 Yu-Jun Zhao , Xuyang Huang , Yi-Rui Zhang , Han-Ze Li , Jian-Xin Zhong

Epistemological consequences of quantum nonlocality (entanglement) are discussed under the assumption of a universally valid Schr\"odinger equation in the absence of hidden variables. This leads inevitably to a {\it many-minds…

Quantum Physics · Physics 2007-05-23 H. D. Zeh

The Stern-Gerlach experiment has played an important role in our understanding of quantum behavior. We propose and analyze a modified version of this experiment where the magnetic field of the detector is in a quantum superposition, which…

Quantum Physics · Physics 2018-03-29 R. G. Daghigh , M. D. Green , C. J. West

It is shown that when properly analyzed using principles consistent with the use of a Hilbert space to describe microscopic properties, quantum mechanics is a local theory: one system cannot influence another system with which it does not…

Quantum Physics · Physics 2020-03-04 Robert B. Griffiths

It was recently shown that, in general, the von Neumann spin entropy of fermionic particles is not invariant under Lorentz boosts. We show that an analogous result can be recovered (at the lowest order of $v^2 /c^2$) using plain…

Quantum Physics · Physics 2020-01-01 Matheus H. Zambianco , Andre G. S. Landulfo , George E. A. Matsas

It is shown that two observers have mutually commuting observables if they are able to prepare in each subsector of their common state space some state exhibiting no mutual correlations. This result establishes a heretofore missing link…

Quantum Physics · Physics 2009-11-10 Detlev Buchholz , Stephen J. Summers

The quantum measurement problem still finds no consensus. Nonlocal interferometry provides an unprecedented experimental probe by entangling two photons in the "measurement state" (MS). The experiments show that each photon "measures" the…

Quantum Physics · Physics 2022-06-14 Art Hobson

Non locality appearing in QFT during the free evolution of localized field states and in the Feynman propagator function is analyzed. It is shown to be connected to the initial non local properties present at the level of quantum states and…

Quantum Physics · Physics 2009-04-28 Fabrizio Buscemi , Giuseppe Compagno

A model for two entangled systems in an EPR setting is shown to reproduce the quantum-mechanical outcomes and expectation values. Each system is represented by a small sphere containing a point-like particle embedded in a field. A quantum…

Quantum Physics · Physics 2009-09-29 A. Matzkin

The Extended Fermi-Hubbard model is a rather studied Hamiltonian due to both its many applications and a rich phase diagram. Here we prove that all the phase transitions encoded in its one dimensional version are detectable via non-local…

Quantum Gases · Physics 2017-12-13 L. Barbiero , S. Fazzini , A. Montorsi

In quantum mechanical bipartite systems, naive extensions of von Neumann's projective measurement to nonlocal variables can produce superluminal signals and thus violate causality. We analyze the projective quantum nondemolition…

Quantum Physics · Physics 2015-02-13 Shih-Yuin Lin

This paper completes a previous work by constructing a class of positive-energy relativistic spatial localization observables in Minkowski spacetime within quantum field theory, using the stress-energy-momentum tensor smeared with suitable…

Mathematical Physics · Physics 2026-04-08 Valter Moretti

The Fewster-Verch (FV) framework provides a local and covariant approach for defining measurements in quantum field theory (QFT). Within this framework, a probe QFT represents the measurement device, which, after interacting with the target…

High Energy Physics - Theory · Physics 2025-10-29 Jan Mandrysch , Miguel Navascués

The locality issue of quantum mechanics is a key issue to a proper understanding of quantum physics and beyond. What has been commonly emphasized as quantum nonlocality has received an inspiring examination through the notion of Heisenberg…

Quantum Physics · Physics 2024-06-11 Otto C. W. Kong

The nonrelativistic limit of nonlocal modifications to the Klein Gordon operator is studied, and the experimental possibilities of casting stringent constraints on the nonlocality scale via planned and/or current optomechanical experiments…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Alessio Belenchia , Dionigi M. T. Benincasa , Stefano Liberati , Francesco Marin , Francesco Marino , Antonello Ortolan

This is an attempt to create a consistent and non-trivial extension of quantum theory, describing in detail the quantum measurement process. A tentative but concrete model is presented, based on the concept of multiple…

Quantum Physics · Physics 2007-05-23 Jose L Balduz

It is currently believed that the local causality of Quantum Field Theory (QFT) is destroyed by the measurement process. This belief is also based on the Einstein-Podolsky-Rosen (EPR) paradox and on the so-called Bell's theorem, that are…

High Energy Physics - Theory · Physics 2009-11-07 Daniele Tommasini

We discuss relations between several relativistic spin observables and derive a Lorentz-invariant characteristic of a reduced spin density matrix.A relativistic position operator that satisfies all the properties of its nonrelativistic…

High Energy Physics - Theory · Physics 2016-12-28 Lucas C. Céleri , Vasilis Kiosses , Daniel R. Terno