11,094 research outputs found
Test of an Analytic, Finite, Non-Perturbative, Gauge-Invariant QCD formulation against elastic pp scattering at the ISR energies
A recent QCD formulation that is non-perturbative, finite, gauge-invariant,
exact emerged from Schwinger's Generating Functional. A first test of the
validity of this formulation is provided here against elastic proton-proton
scattering at the Intersecting Storage Rings, ISR, energies. Extension to LHC
energies is underway.Comment: Conference proceedings for the 15th International Conference of
Numerical Analysis and Applied Mathematics. 2017. Thessaloniki, Greec
Schwinger Generating Functional Derivation of LHC Elastic Proton-Proton Scattering Amplitudes
A recent Schwinger Generating Functional based formulation, by
H.M.Fried,Y.Gabellini,T.Grandou and Y-M.Sheu and P.H.Tsang provided
gauge-invariant, exact, non-perturbative solutions for QCD. After choosing a
renormalization scheme and assuming a simpler 2 body quark-quark scattering
problem, this formalism is tested against experimental elastic proton-proton
scattering at LHC energies (7, 8, 13 TeV). This formulation was previously
compared with ISR energies at (23.5 - 62.5 GeV). The full scattering amplitude
with infinite gluons summed, infinite loops summed and their interference terms
are needed for LHC differential cross-sections.Comment: 16th International Conference of Numerical Analysis and Applied
Mathematics : Analysis of Quantum Field Theory IV, Rhodes, Greece, 13-18
Sept, 201
The 13C nuclear magnetic resonance in graphite intercalation compounds
The (13)C NMR chemical shifts of graphite intercalation compounds were calculated. For acceptor types, the shifts come mainly from the paramagnetic (Ramsey) intra-atomic terms. They are related to the gross features of the two-dimensional band structures. The calculated anisotropy is about -140 ppm and is independent of the finer details such as charge transfer. For donor types, the carbon 2p pi orbitals are spin-polarized because of mixing with metal conduction electrons, thus there is an additional dipolar contribution which may be correlated with the electronic specific heat. The general agreement with experimental data is satisfactory
Sound velocity anisotropy in cubic crystals
Simple analytical expressions may be derived for sound velocities in cubic crystals by using lattice harmonics or functions which are invariant under the crystal symmetry operations. These expressions are in good agreement with the exact results for typical crystals such as metallic iron and potassium fluoride
The Chinese New Middle Class and Green NGOs in South China: Vanguards of Guanxi (Connections)-Seeking, Laggards in Promoting Social Causes?
By examining the emerging Chinese new middle class as well as green non-governmental organisations, this study finds that while the emergence of the Chinese new middle class facilitates the growth of green NGOs, the Chinese new class is not activists or agitators working against the government. Based on in-depth interviews with leaders of green NGOs founded by the Chinese new middle class in Guangdong province, this research examines why green NGOs do not call for or advocate environmental protection It concludes that contrary to conventional wisdom, the Chinese new middle class is a vanguard of guanxi (connections)-seeking, but a laggard in promoting environmental protection and civil-society activism. Green NGOs are principally used as a tool to cultivate social capital in the form of guanxi in order to promote personal material interests
Chiral Symmetry Breaking out of QCD Effective Locality
The QCD non-perturbative property of Effective Locality whose essential
meaning has been disclosed recently, is here questioned about the chiral
symmetry breaking phenomenon, one of the two major issues of the
non-perturbative phase of QCD. As a first attempt, quenching and the eikonal
approximation are used so as to simplify calculations which are quite involved.
Chiral symmetry breaking appears to be realised in close connection to the
Effective Locality mass scale, , as could be expected.Comment: ICNAAM 2018, Analysis of Quantum Field Theory IV Conference extended
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Quantum theory of optical temporal phase and instantaneous frequency. II. Continuous time limit and state-variable approach to phase-locked loop design
We consider the continuous-time version of our recently proposed quantum
theory of optical temporal phase and instantaneous frequency [Tsang, Shapiro,
and Lloyd, Phys. Rev. A 78, 053820 (2008)]. Using a state-variable approach to
estimation, we design homodyne phase-locked loops that can measure the temporal
phase with quantum-limited accuracy. We show that post-processing can further
improve the estimation performance, if delay is allowed in the estimation. We
also investigate the fundamental uncertainties in the simultaneous estimation
of harmonic-oscillator position and momentum via continuous optical phase
measurements from the classical estimation theory perspective. In the case of
delayed estimation, we find that the inferred uncertainty product can drop
below that allowed by the Heisenberg uncertainty relation. Although this result
seems counter-intuitive, we argue that it does not violate any basic principle
of quantum mechanics.Comment: 11 pages, 6 figures, v2: accepted by PR
Rodent models for the analysis of tissue clock function in metabolic rhythms research
The circadian timing system consists on a distributed network of cellular clocks that together coordinate 24-h rhythms of physiology and behavior. Clock function and metabolism are tightly coupled, from the cellular to the organismal level. Genetic and non-genetic approaches in rodents have been employed to study circadian clock function in the living organism. Due to the ubiquitous expression of clock genes and the intricate interaction between the circadian system and energy metabolism, genetic approaches targeting specific tissue clocks have been used to assess their contribution in systemic metabolic processes. However, special requirements regarding specificity and efficiency have to be met to allow for valid conclusions from such studies. In this review, we provide a brief summary of different approaches developed for dissecting tissue clock function in the metabolic context in rodents, compare their strengths and weaknesses, and suggest new strategies in assessing tissue clock output and the consequences of circadian clock disruption in vivo.Fil: Tsang, Anthony H.. University of Lübeck; Alemania. University of Cambridge; Reino UnidoFil: Astiz, Mariana. University of Lübeck; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Leinweber, Brinja. University of Lübeck; AlemaniaFil: Oster, Henrik. University of Lübeck; Alemani
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