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Related papers: Physical consequences of the QED theta angle

200 papers

We present a discussion of the fundamental loss of unitarity that appears in quantum mechanics due to the use of a physical apparatus to measure time. This induces a decoherence effect that is independent of any interaction with the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Rodolfo Gambini , Rafael Porto , Jorge Pullin

The conflict between the determinism of geometry in general relativity and the essential statistics of quantum mechanics blocks the development of a unified theory. Electromagnetic radiation is essential to both fields and supplies a common…

Quantum Physics · Physics 2015-01-30 Daniel C. Galehouse

No experimental evidence exists, to date, whether or not the gravitational field must be quantised. Theoretical arguments in favour of quantisation are inconclusive. The most straightforward alternative to quantum gravity, a coupling…

Quantum Physics · Physics 2017-08-29 André Großardt

We show that the quantum angle measurement for x-polarized photon number states results in an angle which will never correspond to the y-axis for an odd number of photons; yet for an even number of photons it always can. The analogy of this…

Quantum Physics · Physics 2015-12-01 Scott Roger Shepard

Using Chetaev's theorem on stable trajectories in dynamics in the presence of perturbation forces we obtain a generalized stability condition for Hamiltonian systems that has the form of the Schrodinger equation. We show that the energy of…

Quantum Physics · Physics 2008-04-10 V. D. Rusov

Quantum electrodynamics near a boundary is investigated by considering the inertial mass shift of an electron near a dielectric or conducting surface. We show that in all tractable cases the shift can be written in terms of integrals over…

Quantum Physics · Physics 2012-12-14 Robert Bennett , Claudia Eberlein

We describe the effect of the gravitational $\Theta$-parameter on the behavior of the stretched horizon of a black hole in $(3+1)$-dimensions. The gravitational $\Theta$-term is a total derivative, however, it affects the transport…

High Energy Physics - Theory · Physics 2016-12-20 Willy Fischler , Sandipan Kundu

A simple method to compute QED bound state properties is presented, in which binding energy effects are treated non-perturbatively. It is shown that to take the effects of all ladder Coulomb photon exchanges into account, one can simply…

High Energy Physics - Phenomenology · Physics 2009-11-07 J. Pestieau , C. Smith

Quantum eigenstates undergoing cyclic changes acquire a phase factor of geometric origin. This phase, known as the Berry phase, or the geometric phase, has found applications in a wide range of disciplines throughout physics, including…

Quantum Physics · Physics 2010-09-13 J. M. Robbins

It is hypothesised, following Conrad et al. (1988) (http://www.tcm.phy.cam.ac.uk/~bdj10/papers/urbino.html) that quantum physics is not the ultimate theory of nature, but merely a theoretical account of the phenomena manifested in nature…

Quantum Physics · Physics 2012-01-04 Brian D. Josephson

Some of the important non-classical aspects of quantum mechanics can be described in more intuitive terms if they are reformulated in a geometrical picture based on an extension of the classical phase space. This contribution presents…

Quantum Physics · Physics 2023-01-13 Martin Bojowald

The presence of noncyclic geometric invariant is revealed in all the phenomena where particle generation from vacuum or vacuum condensates appear. Aharonov--Anandan invariants then can help to study such systems and can represent a new tool…

High Energy Physics - Theory · Physics 2013-11-13 Antonio Capolupo , Giuseppe Vitiello

A canonical formalism is presented which allows for investigations of quantum radiation induced by localized, smooth disturbances of classical background fields by means of a perturbation theory approach. For massless, non-selfinteracting…

Quantum Physics · Physics 2009-10-31 Ralf Schützhold , Guenter Plunien , Gerhard Soff

Constructing the Hamiltonian in the $\eta$-representation, we explore the geometric phase in the Taub-NUT spacetime, which is spherically symmetric and stationary. The geometric phase around a non-rotating Taub-NUT spacetime reveals both…

General Relativity and Quantum Cosmology · Physics 2023-10-19 Chandrachur Chakraborty , Banibrata Mukhopadhyay

We study a quantum mechanical toy model that mimics some features of a quenched phase transition. Both by virtue of a time-dependent Hamiltonian or by changing the temperature of the bath we are able to show that even after classicalization…

Quantum Physics · Physics 2009-11-07 Nuno D. Antunes , Fernando C. Lombardo , Diana Monteoliva

In recent work (Nii et al., arXiv:1603.06291; Iinuma et al., Phys. Rev. A 93, 032104 (2016)(arXiv:1510.03958)) we have studied the relation between experimental outcomes and the physical properties represented by Hilbert space operators of…

Quantum Physics · Physics 2016-05-26 Holger F. Hofmann , Taiki Nii , Masataka Iinuma

The technique of quantum electrodynamics (QED) calculations of energy levels in the helium atom is reviewed. The calculations start with the solution of the Schr\"odinger equation and account for relativistic and QED effects by perturbation…

Atomic Physics · Physics 2021-07-14 Vladimir A. Yerokhin , Vojtech Patkos , Krzysztof Pachucki

In this short paper, we propose a new quantum effect that naturally emerges from describing the quantum particle as a classical fluid. Following the hydrodynamical formulation of quantum mechanics for a particle in a finite convex region,…

Quantum Physics · Physics 2024-10-01 Tomer Shushi

In this thesis we investigate quantum mechanical effects to various aspects of gravitational collapse. These quantum mechanical effects are implemented in the context of the Functional Schr\"odinger formalism. The Functional Schr\"odinger…

General Relativity and Quantum Cosmology · Physics 2010-01-13 Eric Greenwood

Everett's concept of relative state is used to introduce a geometric phase that depends nontrivially on entanglement in a pure quantum state. We show that this phase can be measured in multiparticle interferometry. A correlation-dependent…

Quantum Physics · Physics 2015-05-13 Erik Sjöqvist