119174074
Smooth Solutions and Discrete Imaginary Mass of the Klein-Gordon Equation in the de Sitter Background
Using methods in the theory of semisimple Lie algebras, we can obtain all smooth solutions of the Klein-Gordon equation on the 4-dimensional de Sitter spacetime (dS^4). The mass of a Klein-Gordon scalar on dS^4 is related to an eigenvalue of the Casimir operator of so(1,4). Thus it is discrete, or quantized. Furthermore, the mass m of a Klein-Gordon scalar on dS^4 is imaginary: m^2 being proportional to -N(N+3), with N >= 0 an integer.
122921314
Smooth U(1) Gauge Potentials on the de Sitter Spacetime
Using the methods of Lie groups and Lie algebras, we solved U(1) gauge potentials on the de Sitter background. Resulted gauge potentials are smooth on the whole spacetime, satisfying the Lorentz gauge condition. It is shown that electromagnetic fields on the de Sitter background could not be source free.
16106369
The Euler–Lagrange Cohomology and General Volume-Preserving Systems
We briefly introduce the concept of Euler–Lagrange cohomology groups on a symplectic manifold (ℳ2n, ω) and systematically present the general form of volume-preserving equations on the manifold from the cohomological point of view. It is shown that for every volume-preserving flow generated by these equations there is an important two-form that plays the analog role with the Hamiltonian in the Hamilton mechanics. In addition, the ordinary canonical equations with Hamiltonian H are included as a special case with the two-form . The other volume preserving systems on (ℳ2n, ω) are studied. The relations between our approach and Feng–Shang's volume-preserving systems as well as the Nambu mechanics are also explored.
115169240
The principle of relativity and the special relativity triple
Abstract Based on the principle of relativity and the postulate on universal invariant constants ( c , l ) as well as Einstein's isotropy conditions, three kinds of special relativity form a triple with a common Lorentz group as isotropy group under full Umov–Weyl–Fock–Lorentz transformations among inertial motions.
119056121
A study of antineutrino spectra from spent nuclear fuel at Daya Bay
The Daya Bay Reactor Antineutrino Experiment is designed to determine the as yet unknown neutrino mixing angle, θ13, by measuring the disappearance of electron antineutrinos from several nuclear reactor cores. The projected sensitivity in sin2 (2θ13) of better than 0.01 at a 90% CL should be achieved after three years of data-taking. Antineutrinos emitted from spent nuclear fuel (SNF) distort the soft part of the energy spectrum. In this article, a calculation of the antineutrino spectra from the long-life isotopes in SNF is performed. A non-equilibrium generation of long half-life isotopes during the running time of the reactor is also analyzed. Finally, we show that the antineutrino event rate contribution from SNF, which has been stored in the SNF pool for several years, may be non-negligible.
119450917
Triality of conformal extensions of three kinds of special relativity
The conformal extensions of three kinds of special relativity with ISO(1,3)/SO(1,4)/SO(2,3) invariance on Mink/dS/AdS space, respectively, are realized on an SO(2,4)/Z(2) invariant projective null cone [N] as the (projective) boundary of the 5-d AdS space. The relations among the conformal Mink/dS/AdS spaces, the motions of light signals and the conformal field theories on them can be given. Thus, there should be a triality for these conformal issues and the conjectured AdS/CFT correspondence.
118116548
GeV excess in the Milky Way: Depending on Diffuse Galactic gamma ray Emission template?
University of Chinese Academy of Sciences, Yuquan Road 19, Beijing, 100049, China.(Dated: June 27, 2014)Several groups have analyzed the publicly-available Fermi-LAT data and reported a spatiallyextended gamma rays excess of around 1−3 GeV from the region surrounding the Galactic Centerthat might originate from annihilation of dark matter particles with a rest mass m