English
Related papers

Related papers: Four questions for quantum-classical hybrid theory

200 papers

The usual formulation of quantum theory is based on rather obscure axioms (employing complex Hilbert spaces, Hermitean operators, and the trace rule for calculating probabilities). In this paper it is shown that quantum theory can be…

Quantum Physics · Physics 2007-05-23 Lucien Hardy

Assuming that Quantum Mechanics is universal and that it can be applied over all scales, then the Universe is allowed to be in a quantum superposition of states, where each of them can correspond to a different space-time geometry. How can…

General Relativity and Quantum Cosmology · Physics 2024-02-27 José Luis Gaona-Reyes , Lucía Menéndez-Pidal , Mir Faizal , Matteo Carlesso

Recently, it has been argued that quantum mechanics is complete, and that quantum states vectors are necessarily in one-to-one correspondence with the elements of reality, under the assumptions that quantum theory is correct and that…

Quantum Physics · Physics 2013-06-24 GianCarlo Ghirardi , Raffaele Romano

We develop a hybrid semiclassical method to study the time evolution of one dimensional quantum systems in and out of equilibrium. Our method handles internal degrees of freedom completely quantum mechanically by a modified time evolving…

Statistical Mechanics · Physics 2019-03-20 Catalin Pascu Moca , Márton Kormos , Gergely Zaránd

This is an extended discussion of Ref.[1], presenting a nonlinear dynamical model of quantum collapse, with randomness emerging from self-generated noise. Here we focus on a few issues: 1) the way chaos theory explains "deterministic but…

Quantum Physics · Physics 2019-09-20 Tamás Geszti

Based on a number of experimentally verified physical observations, it is argued that the standard principles of quantum mechanics should be applied to the Universe as a whole. Thus, a paradigm is proposed in which the entire Universe is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. S. Eakins

Based on Koopman formalism for classical statistical mechanics, we propose a formalism to define hybrid quantum-classical dynamical systems by defining (outer) automorphisms of the C*-algebra of hybrid operators and realizing them as linear…

Mathematical Physics · Physics 2023-08-29 C. Bouthelier-Madre , J. Clemente-Gallardo , L. González-Bravo , D. Martínez-Crespo

There are several important philosophical problems to which quantum mechanics is often said to have made significant contributions: - Determinism: quantum theory has been taken to refute determinism; -Free Will: in turn, this is thought to…

Quantum Physics · Physics 2025-10-29 Valia Allori

Quantum trajectory techniques have been used in the theory of open systems as a starting point for numerical computations and to describe the monitoring of a quantum system in continuous time. Here we extend this technique and use it to…

Quantum Physics · Physics 2026-05-05 Alberto Barchielli

The convenience of coherent state representation is discussed from the viewpoint of what is in a broad sense called the measurement problem in quantum mechanics. Standard quantum theory in coherent state representation is intrinsically…

Quantum Physics · Physics 2008-02-03 Lajos Diosi

We propose a hybrid quantum-classical algorithm for the simulation of real-time dynamics in interacting quantum field theories coupled to classical fields, focusing on the self-consistent estimation of semiclassical backreaction. By…

General Relativity and Quantum Cosmology · Physics 2026-03-27 Carlos Fulgado-Claudio , Daniel González-Cuadra , Jose Beltrán Jiménez , Alejandro Bermudez

In light of G\"{o}del's undecidability results (incomplete theorems) for math, quantum indeterminism indicates that physics and the Universe may be indeterministic, incomplete, and open in nature, and therefore demand no single unification…

General Physics · Physics 2020-03-11 Wanpeng Tan

Commutativity of the diagram of the maps connecting three one--particle state, implied by the Equivalence Postulate (EP), gives a cocycle condition which unequivocally leads to the quantum Hamilton--Jacobi equation. Energy quantization is a…

High Energy Physics - Theory · Physics 2017-08-23 Marco Matone

Standard quantum theory represents a composite system at a given time by a joint state, but it does not prescribe a joint state for a composite of systems at different times. If a more even-handed treatment of space and time is possible,…

Quantum Physics · Physics 2017-10-27 Dominic Horsman , Chris Heunen , Matthew F. Pusey , Jonathan Barrett , Robert W. Spekkens

We consider the canonical quantization of an ordinary fluid. The resulting long-distance effective field theory is derivatively coupled, and therefore strongly coupled in the UV. The system however exhibits a number of peculiarities,…

High Energy Physics - Theory · Physics 2011-06-23 Solomon Endlich , Alberto Nicolis , Riccardo Rattazzi , Junpu Wang

Quantum theory demands that, in contrast to classical physics, not all properties can be simultaneously well defined. The Heisenberg Uncertainty Principle is a manifestation of this fact. Another important corollary arises that there can be…

Starting from the Schr\"odinger-equation of a composite system, we derive unified dynamics of a classical harmonic system coupled to an arbitrary quantized system. The classical subsystem is described by random phase-space coordinates…

Quantum Physics · Physics 2007-05-23 Lajos Diosi

A canonical formulation of coupled classical-quantum dynamics is presented. The theory is named symmetric hybrid dynamics. It is proved that under some general conditions its predictions are consistent with the full quantum ones. Moreover…

Quantum Physics · Physics 2007-05-23 Nuno Costa Dias , Joao Nuno Prata

Quantum dynamics can be regarded as a generalization of classical finite-state dynamics. This is a familiar viewpoint for workers in quantum computation, which encompasses classical computation as a special case. Here this viewpoint is…

Quantum Physics · Physics 2015-09-01 Norman Margolus

We discuss the transition from a quantum to a classical domain for a model where a separation into environment and system is explicitely not given. Utilizing the coarse graining procedure for free quantum fields we also apply the projection…

Quantum Physics · Physics 2007-05-23 A. M. Lisewski