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Related papers: Mixed Quantum States with Variable Planck Constant

200 papers

The distinction between pure states and mixed states is a kernel ingredient of what is considered to be the standard formulation of quantum mechanics and plays today a kernel role in foundational debates about the meaning of quantum…

History and Philosophy of Physics · Physics 2024-11-01 Christian de Ronde , César Massri

The current observational and experimental bounds on the time variation of the constants of nature (the fine structure constant $\alpha$, the gravitational constant $G$ and the proton-electron mass ratio $\mu=m_p/m_e$) are reviewed.

General Relativity and Quantum Cosmology · Physics 2012-01-03 Takeshi Chiba

Astrophysical indications that the fine structure constant has undergone a small time variation during the cosmological evolution are discussed within the framework of the standard model of the electroweak and strong interactions and of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Xavier Calmet , Harald Fritzsch

The Planck constant $h$ is one of the most significant constants in quantum physics. Recently, the precision measurement of the numeral value of $h$ has been a hot issue due to its important role in establishment for both a new SI and a…

Instrumentation and Detectors · Physics 2015-06-23 Shisong Li , Zhonghua Zhang , Wei Zhao , Zhengkun Li , Songling Huang

The cosmological implications of introducing a variation to the fine structure `constant', \alpha are examined within the context of Loop Quantum Cosmology. The evolution of \alpha is described using the model introduced by Bekenstein,…

General Relativity and Quantum Cosmology · Physics 2016-04-29 David Sloan

The fine structure constant $\alpha$ and the ratio $h/m_{\mathrm{u}}$ between the Planck constant and the unified atomic mass are keystone constants for the determination of other fundamental physical constants, especially the ones involved…

Atomic Physics · Physics 2019-06-26 Pierre Cladé , François Nez , François Biraben , Saïda Guellati-Khelifa

In this review we discuss the progress of the past decade in testing for a possible temporal variation of the fine structure constant $\alpha$. Advances in atomic sample preparation, laser spectroscopy and optical frequency measurements led…

Quantum Physics · Physics 2015-05-13 N. Kolachevsky , A. Matveev , J. Alnis , C. Parthey , T. Steinmetz , T. Wilken , R. Holzwarth , Th. Udem , T. W. Haensch

Although Planck's constant h is currently regarded as the elementary quantum of action appearing in quantum theory, it can also be interpreted as the multiplicative scale factor setting the scale of classical zero-point radiation appearing…

Classical Physics · Physics 2013-01-28 Timothy H. Boyer

It is well known that, due to the uncertainty principle, the Planck constant sets a resolution boundary in phase space and the resulting trade-off in resolution between incompatible measurements has been thoroughly investigated. It is also…

Quantum Physics · Physics 2021-11-08 Oleg Kabernik

Several quantum gravity and string theory thought experiments indicate that the Heisenberg uncertainty relations get modified at the Planck scale so that a minimal length do arises. This modification may imply a modification of the…

Classical Physics · Physics 2020-09-28 O. I. Chashchina , A. Sen , Z. K. Silagadze

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

The progress of Particle Physics is closely linked to the progress in the understanding of the fundamental constants, like the finestructure constant, the mass of the electron or nucleon, or the electroweak mixing angle. The relation…

High Energy Physics - Phenomenology · Physics 2015-06-25 H. Fritzsch

It has been argued that any evolution law taking pure states to mixed states in quantum field theory necessarily gives rise to violations of either causality or energy-momentum conservation, in such a way as to have unacceptable…

High Energy Physics - Theory · Physics 2009-10-28 William G. Unruh , Robert M. Wald

The boundary between the classical and quantum worlds has been intensely studied. It remains fascinating to explore how far the quantum concept can reach with use of specially fabricated elements. Here we employ a tunable flux qubit with…

Mesoscale and Nanoscale Physics · Physics 2011-07-04 A. Fedorov , P. Macha , A. K. Feofanov , C. J. P. M. Harmans , J. E. Mooij

If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gia Dvali , Matias Zaldarriaga

From astrophysics there are indications that the finestructure constant $\alpha $ has changed during the past 10 billion years. Within grand unification one can deduce that also the QCD scale has changed. Tests for a time variation of this…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

We start with a brief account of the latest analysis of the Oklo phenomenon providing the still most stringent constraint on time-variability of the fine- structure constant $\alpha$. Comparing this with the recent result from the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Yasunori Fujii

In present paper we confirm our previous result [5] that the Planck constant is adiabatic invariant of electromagnetic field propagating on the adiabatically changed Finslerian manifold. Direct calculation from cosmological parameters gives…

General Physics · Physics 2024-05-21 Anton A. Lipovka

A formalism is developed for describing approximate classical behaviour in finite (but possibly large) quantum systems. This is done in terms of a structure common to classical and quantum mechanics, viz. a Poisson space with a transition…

Quantum Physics · Physics 2015-06-26 N. P. Landsman

Review of recent works devoted to the temporal and spatial variation of the fundamental constants and dependence of the fundamental constants on the gravitational potential (violation of local position invariance) is presented. We discuss…

Nuclear Theory · Physics 2009-08-18 V. V. Flambaum