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911.
Bipin Singh Koranga Rajesh Pandey 《International Journal of Theoretical Physics》2011,50(5):1468-1473
Neutrino mixing lead to a non zero contribution to the dark energy of the universe. We assume that the neutrino masses and
mixing arise through physics at a scale intermediate between Planck Scale and the electroweak scale. The mechanism of neutrino
mixing is a possible candidate to contribute the cosmological dark energy. Quantum gravitational (Planck scale) effects lead
to an effective SU(2)
L
×U(1) invariant dimension-5 Lagrangian involving neutrino and Higgs fields, which gives rise to additional terms in neutrino
mass matrix. There additional term can be considered to be perturbation of the GUT scale bi-maximal neutrino mass matrix.
We assume that the gravitational interaction is flavor. In this paper, we discuss the three flavor neutrino mixing and cosmological
dark energy contributes due to Planck scale effects. 相似文献
912.
We consider Hermitian and symmetric random band matrices H in d ≥ 1 dimensions. The matrix elements H xy , indexed by \({x,y \in \Lambda \subset \mathbb{Z}^d}\), are independent, uniformly distributed random variables if \({\lvert{x-y}\rvert}\) is less than the band width W, and zero otherwise. We prove that the time evolution of a quantum particle subject to the Hamiltonian H is diffusive on time scales \({t\ll W^{d/3}}\). We also show that the localization length of the eigenvectors of H is larger than a factor W d/6 times the band width. All results are uniform in the size \({\lvert{\Lambda}\rvert}\) of the matrix. 相似文献
913.
914.
Cosmological models with variable G in C-field cosmology for barotropic fluid distribution in FRW space-time are investigated. To get the deterministic model of the
universe, we have assumed that G=R
n
where R is the scale factor and n the constant. To obtain the results in terms of cosmic time t, we have assumed n=−1. We find that for n=−1, Creation field (C) and spatial volume increase with time, G and ρ (matter density) decreases with time, the model represent accelerating universe. Thus inflationary scenario exists in the
model. The model is also free from horizon. The results so obtained match with the astronomical observations. 相似文献
915.
We prove that the maximum norm of the deformation tensor of velocity gradients controls the possible breakdown of smooth(strong)
solutions for the 3-dimensional (3D) barotropic compressible Navier-Stokes equations. More precisely, if a solution of the
3D barotropic compressible Navier-Stokes equations is initially regular and loses its regularity at some later time, then
the loss of regularity implies the growth without bound of the deformation tensor as the critical time approaches. Our result
is the same as Ponce’s criterion for 3-dimensional incompressible Euler equations (Ponce in Commun Math Phys 98:349–353, 1985). In addition, initial vacuum states are allowed in our cases. 相似文献
916.
Dao-Ming Lu 《International Journal of Theoretical Physics》2011,50(6):1809-1818
We study the entanglement evolution between two atoms, which are initially entangled with a third atom and trapped in two
separated cavities coupled by an optical fiber. We also investigate the temporal evolution in the entanglement between the
atom and the local cavity mode. The influence of the state-selective measurement on the atom outside the cavities and the
influence of cavity-fiber coupling coefficient on the entanglement are discussed. The results show that the entanglement can
be strengthened through the state-selective measurement on the atom outside the cavities. We also find that, by increasing
the cavity-fiber coupling coefficient, the atom-atom entanglement is strengthened, but the atom-cavity entanglement is weakened. 相似文献
917.
Xing-Lei Xu Shi-Min Xu Hong-Qi Li Ji-Suo Wang 《International Journal of Theoretical Physics》2011,50(2):385-394
The new coherent-entangled state |z,x;θ〉 is proposed in the two-mode Fock space, which exhibits both the properties of coherent and entangled states. The completeness
relation of |z,x;θ〉 is proved by virtue of the technique of integral within an ordered product of operators. A generalized Hadamard-Fresnel
complementary transformation derived by virtue of the coherent-entangled state |z,x;θ〉, which is unitary. The new unitary operator plays the role of both Hadamard transformation for ([^(a)]1sinq-[^(a)]2cosq)(\hat{a}_{1}\sin\theta -\hat{a}_{2}\cos\theta) and Fresnel transformation for ([^(a)]1cosq+[^(a)]2sinq)(\hat{a}_{1}\cos\theta +\hat{a}_{2}\sin\theta), respectively. 相似文献
918.
Nicholas Crawford 《Journal of statistical physics》2011,142(1):11-42
Consider the classical XY model in a weak random external field pointing along the Y axis with strength ε. We study the behavior of this model as the range of the interaction is varied. We prove that in any dimension d≥2 and for all ε sufficiently small, there is a range L=L(ε) so that whenever the inverse temperature β is larger than some β(ε), there is strong residual ordering along the X direction. 相似文献
919.
V. Matolín J. Libra I. Matolínová V. Nehasil L. Sedlá?ek F. Šutara 《Applied Surface Science》2007,254(1):153-155
The reactive vacuum deposition of CeO2 on Cu(1 1 1) surface in oxygen atmosphere provides high quality epitaxial ceria overlayers. We report the growth characteristics of Ce oxide, the structures, and the temperature stability of the oxide phases as investigated by low-energy electron diffraction (LEED) and X-ray photoelectron spectroscopy. We find that Ce oxide on the Cu(1 1 1) grows initially in the form of islands giving sharp hexagonal LEED pattern of the CeO2(1 1 1) structure corresponding to the (1.5 × 1.5) structure. The CeO2-Cu(1 1 1) films exhibited mixed valence states and temperature dependent CeO2-Ce2O3 transition above 900 K due to the vacuum annealing. The transition progressed more rapidly at the surface, probably by formation of oxygen vacancies. 相似文献
920.
Nadia Tagnaouti Sven Loebrich Frank Heisler Yvonne Pechmann Susanne Fehr Adèle De Arcangelis Elisabeth Georges-Labouesse Josephine C Adams Matthias Kneussel 《BMC neuroscience》2007,8(1):28