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Related papers: The "proton spin crisis" - a quantum query

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In 2010 the proton charge radius was extracted for the first time from muonic hydrogen, a bound state of a muon and a proton. The value obtained was five standard deviations away from the regular hydrogen extraction. Taken at face value,…

High Energy Physics - Phenomenology · Physics 2019-09-27 Gil Paz

One of the important questions in high energy physics is the relation of quark and gluon spin to that of the nucleons which they comprise. Polarization experiments provide a mechanism to probe the spin properties of elementary particles and…

High Energy Physics - Phenomenology · Physics 2014-11-17 Gordon P. Ramsey

The neutron spin structure function, $g_{1n}$, has been of considerable interest recently in connection with the Bjorken sum rule and the proton spin crisis. Work on this problem has concentrated on measurements at low-$x$. We recall the…

High Energy Physics - Experiment · Physics 2010-02-17 Anthony W. Thomas

Mesoscopic conductors are electronic systems of sizes in between nano- and micrometers, and often of reduced dimensionality. In the phase-coherent regime at low temperatures, the conductance of these devices is governed by quantum…

Mesoscale and Nanoscale Physics · Physics 2008-03-27 Michael Wimmer , Matthias Scheid , Klaus Richter

By 1930, at a time when the new physics based on relativity and quantum theory had reached a state of consolidation, problems of a foundational kind began to abound. Physicists began to speak of a new "crisis" and envisage a forthcoming…

History and Philosophy of Physics · Physics 2011-11-29 Helge Kragh

We study the single-spin asymmetry, $A_N(t)$, arising from Coulomb-nuclear interference (CNI) at small 4-momentum transfer squared, $-t=q^2$, aiming at explanation of the recent data from the PHENIX experiment at RHIC on polarized…

High Energy Physics - Phenomenology · Physics 2017-11-08 Michal Krelina , Boris Z. Kopeliovich

Until this day no electric dipole moment of the neutron (nEDM) has been observed. Why it is so vanishing small, escaping detection in the last 50 years, is not easy to explain. In general it is considered as the most sensitive probe for the…

Nuclear Experiment · Physics 2016-08-03 P. Schmidt-Wellenburg

We examine the single-spin asymmetry (SSA) caused by the five-quark components of the proton for semi-inclusive electroproduction of charged pions in deep-inelastic scattering on a transversely polarized hydrogen target. The large SSA is…

High Energy Physics - Phenomenology · Physics 2008-07-16 F. X. Wei , B. S. Zou

The intrinsic quark-antiquark pairs generated by the minimal energy nonperturbative meson-baryon fluctuations in the nucleon sea provide a consistent framework for understanding a number of empirical anomalies observed in the deep inelastic…

High Energy Physics - Phenomenology · Physics 2008-02-03 B. -Q. Ma , S. J. Brodsky

We review progress on the spintronics proposal for quantum computing where the quantum bits (qubits) are implemented with electron spins. We calculate the exchange interaction of coupled quantum dots and present experiments, where the…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Hans-Andreas Engel , L. P. Kouwenhoven , Daniel Loss , C. M. Marcus

Until now no electric dipole moment of the neutron (nEDM) has been observed. Why it is so vanishingly small, escaping detection for the last 65 years, is not easy to explain. In general it is considered as one of the most sensitive probes…

High Energy Physics - Experiment · Physics 2017-10-11 P. Schmidt-Wellenburg

The real, interacting elementary particle always consits of a 'bare' particle and a cloud of virtual particles mediating a self-interaction and/or the bond inside a composite object. In this letter we discuss the question of spin content of…

High Energy Physics - Phenomenology · Physics 2015-11-10 Petr Zavada

Quantum states are described by wave functions whose phases cannot be directly measured, but which play a vital role in quantum effects such as interference and entanglement. The loss of the relative phase information, termed decoherence,…

Chemical Physics · Physics 2019-12-20 Jia Chen , Cong Hu , John F. Stanton , Stephen Hill , Hai-Ping Cheng , Xiao-Guang Zhang

Although the concept of a quantum phase transition has been known since the nineteen seventies, their importance as a source of radical transformation in metallic properties has only recently been appreciated. A quantum critical point forms…

Strongly Correlated Electrons · Physics 2007-05-23 P. Coleman , C. Pepin

It is shown, in the context of a recent formulation of elementary particles in terms of, what may be called, a Quantum Mechanical Kerr-Newman metric, that spin is a consequence of a space-time cut off at the Compton wavelength and Compton…

Quantum Physics · Physics 2007-05-23 B. G. Sidharth

Time and again, spin has been a key element in the exploration of fundamental physics. Spin-dependent observables have often revealed deficits in the assumed theoretical framework and have led to novel developments and concepts. Spin is…

Experimental and theoretical progress toward quantum computation with spins in quantum dots (QDs) is reviewed, with particular focus on QDs formed in GaAs heterostructures, on nanowire-based QDs, and on self-assembled QDs. We report on a…

Mesoscale and Nanoscale Physics · Physics 2013-03-11 Christoph Kloeffel , Daniel Loss

We argue that a large fraction of the proton spin comes from a contribution due to a nonperturbative intrinsic charm component of the proton. An account of this contribution removes an apparent contradiction between the data and exact…

High Energy Physics - Phenomenology · Physics 2008-02-03 Igor Halperin , Ariel Zhitnitsky

Circulating orbital currents produced by the spin-orbit interaction for a single electron spin in a quantum dot are explicitly evaluated at zero magnetic field, along with their effect on the total magnetic moment (spin and orbital) of the…

Mesoscale and Nanoscale Physics · Physics 2014-07-24 J. van Bree , A. Yu. Silov , P. M. Koenraad , M. E. Flatté

The experimental shock wave, discovery in quantum systems is the important one through last years. This effect has several phenomenological explanations. It seems to us there is interesting, especially from the systematical point of view,…

Quantum Physics · Physics 2017-02-03 Evgeny Perepelkin , Boris Sadovnikov , Natalia Inozemtseva
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