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We study a nonrelativistic system made of two quantum particles constrained to move on a line and a spin located at a fixed point of the line. Initially the two particles are in a maximally entangled state and the spin is down. The first…

Mathematical Physics · Physics 2026-02-25 Riccardo Adami , Luigi Barletti , Alessandro Teta

The Robertson -- Schr\"{o}dinger, Heisenberg -- Robertson and Trifonov uncertainty relations for arbitrary two functions $f_{1}$ and $f_{2}$ depending on the quantum phase and the number of photons respectively, are given. Intelligent…

It is commonly assumed that zero and non-zero photon mass would lead to qualitatively different physics. For example, massless photon has two polarization degrees of freedom, while massive photon at least three. This feature seems…

General Physics · Physics 2016-08-12 Roman Sverdlov

Motivated mainly by the fact that no charged elementary particles having zero mass have been observed up to now, we investigate the question whether the mass of the elementary particles is connected with their electric charge and whether…

General Physics · Physics 2011-03-04 Athanasios Markou

Optical experiments designed to explore quantum complementarity are reanalyzed. It is argued that, for each, a classical explanation is not only possible, but more coherent and less contrived. The final conclusion is that these experiments…

Quantum Physics · Physics 2007-05-23 A. F. Kracklauer

It is a well-known fact that helicity is a Lorentz-invariant for massless but not for massive particles. Nevertheless, a satisfactory proof of this fact and a detailed analysis on the relative orientation between spin and the momentum are…

High Energy Physics - Theory · Physics 2016-09-08 Cheng-Yang Lee

In this work, inspired by the definition of the photon surface given by Claudel, Virbhadra, and Ellis, we give an alternative quasi-local definition to study the circular orbits of single-pole particles. This definition does not only apply…

General Relativity and Quantum Cosmology · Physics 2023-08-30 Yong Song , Yiting Cen , Leilei Tang , Jiabao Hu , Kai Diao , Xiaofeng Zhao , Shunping Shi

The traditional interpretation of radiative emission and absorption asserts that photons are created and annihilated in such processes. A Gedanken experiment is considered in which kinetic energy from observed photons is systematically…

Classical Physics · Physics 2015-06-26 Robert J. Buenker

The polarization of final-state photons is a critical observable for probing the fundamental mechanisms of particle and nuclear interactions, providing insights into spin and parity structure that are inaccessible through cross-section…

High Energy Physics - Experiment · Physics 2026-01-30 Xiao-Rong Lv , Yu-Tie Liang , Boxing Gou , Chuang-Xin Lin , Ai-Qiang Guo

It is suggested that a moving canonical particle interacts with a vacuum regarded as a "soft" cellular space. The interaction results into the emergence of elementary excitations of space - inertons - surrounding the particle. It is assumed…

Quantum Physics · Physics 2007-05-23 Volodymyr Krasnoholovets

In this study, the Majorana equation for particles with arbitrary spin is solved for a half-integer spin free particle. The solution for the fundamental state, corresponding to the reference frame in which the particle is at rest, is…

General Physics · Physics 2019-02-08 Luca Nanni

Entanglement is a fundamental feature of quantum theory as well as a key resource for quantum computing and quantum communication, but the entanglement mechanism has not been found at present. We think when the two subsystems exist…

Quantum Physics · Physics 2016-06-21 Xiang-Yao Wu , Xiao-Jing Liu , Jing-Bin Lu , Tian-Shun Li , Si-Qi Zhang , Yu Liang , Ji Ma , Hong Li

The interaction between three photons is studied in de Sitter ambient space formalism. As a special case the half harmonic generator is considered, {\it i.e.} one photon decays to two same-energy photons. The scattering matrix elements are…

General Relativity and Quantum Cosmology · Physics 2025-10-21 Y. Ahmadi , M. V. Takook

Photons are almost involved in each field of science and daily life of everyone. However, there are still some fundamental and puzzling questions such as what a photon is.The expressions of electromagnetic fields of a photon are here…

Optics · Physics 2018-05-31 Shan-Liang Liu

For the magnetic field in order of the Schwinger critical value or much larger it, the effective mass of a real photon with a preset polarization is investigated in the energy region including two lower creation thresholds of electron and…

High Energy Physics - Theory · Physics 2015-12-09 V. M. Katkov

We analyse the Anderson-Higgs mechanism of photon mass acquisition in a plasma and study the contribution to the mass from the orbital angular momentum acquired by a beam of photons when it crosses a spatially structured charge…

Plasma Physics · Physics 2014-11-20 F. Tamburini , A. Sponselli , B. Thidé , J. T. Mendonça

The oldest enigma in fundamental particle physics is: Where do the observed masses of elementary particles come from? Inspired by observation of the empirical particle mass spectrum we propose that the masses of elementary particles arise…

General Physics · Physics 2014-02-04 Johan Hansson

Quantum entanglement is central to both the foundations of quantum mechanics and the development of new technologies in information processing, communication, and sensing. Entanglement has been realised in a variety of physical systems,…

Quantum Physics · Physics 2025-04-18 Jan-Wilke Henke , Hao Jeng , Murat Sivis , Claus Ropers

The law of balance of angular momentum is shown to imply the existence of absolute time, a fundamental physical quantity that is independent of the motion or position of the observer. Absolute time implies the notion of absolute…

General Physics · Physics 2023-03-29 A. Paglietti

Newton introduced the concept of mass in his {\it Principia} and gave an intuitive explanation for what it meant. Centuries have passed and physicists as well as philosophers still argue over its meaning. Three types of mass are generally…

General Physics · Physics 2012-01-19 J. L. Fry , Z. E. Musielak