Search results for " quantum mechanics"
showing 5 items of 245 documents
Measurement of the spin-dependent structure function g1(x) of the deuteron
1993
We report on the first measurement of the spin-dependent structure function g1d of the deuteron in the deep inelastic scattering of polarised muons off polarised deuterons, in the kinematical range 0.006<x<0.6, 1 GeV2<Q2<30 GeV2. The first moment, Γ1d=sh{phonetic}01 g1d dx=0.023±0.020 (stat.) ± 0.015 (syst.), is smaller than the prediction of the Ellis-Jaffe sum rules. Using earlier measurements of g1p, we infer the first moment of the spin-dependent neutron structure function g1n. The difference Γ1p-Γ1n=0.20 ±0.05 (stat.) ± 0.04 (syst.) agrees with the prediction of the Bjorken sum rule, Γ1p-Γ1n=0.191 ±0.002.
Effective charge from lattice QCD
2020
Using lattice configurations for quantum chromodynamics (QCD) generated with three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction of QCD's renormalisation-group-invariant process-independent effective charge, $\hat\alpha(k^2)$. Owing to the dynamical breaking of scale invariance, evident in the emergence of a gluon mass-scale, this coupling saturates at infrared momenta: $\hat\alpha(0)/\pi=0.97(4)$. Amongst other things: $\hat\alpha(k^2)$ is almost identical to the process-dependent (PD) effective charge defined via the Bjorken sum rule; and also that PD charge which, employed in the one-loop evolution equations, delivers agreement between pion parton di…
A possible quantum motivation of the structure of quantum group
2011
We propose a (first) simple natural model of a non-finitely generated braided non-commutative Hopf Algebra, suggested by the elementary quantum mechanics.
Sobre la naturalización de la lógica*
2003
El presente artículo se ocupa de dar razones en contra de la naturalización de la lógica, en tanto en cuanto esto signifique una revisión de esta ciencia. El trabajo critica cada uno de los intentos históricos importantes que ha habido de revisión de las leyes lógicas -- intuicionismo, lógica cuántica, lógicas alternativas - y también intenta argumentar que el problema de la interpretación de la mecánica cuántica no tiene nada que ver con la naturalización de la lógica. This article is devoted to give reasons against the naturalization of logic, in a sense which entails a revision of this science. The paper criticizes each historical important attempt to revise logical laws - intuitionism, …