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In this paper we extend previous work on the relation between the complex structure moduli of the underlying Calabi–Yau manifold in five dimensional supergravity with the time evolution of an embedded 3-brane. We numerically solve the fields' equations for such a construction and focus on dust and radiation filled branes; with the possible application of modeling the Universe as a brane-world. It is shown that in both cases the time evolution of the moduli causally connects to the expansion of the brane-world. We also find that in most cases considered there is an early short period of rapid accelerative expansion, indicating an inflationary epoch. We report on these results; leaving analysis of the underlying causes for future work. [ABSTRACT FROM AUTHOR]

A theoretical investigation has been made of obliquely propagating nonlinear electrostatic shock structures. The reductive perturbation method has been used to derive the Korteweg-de Vries-Burger (KdV-Burger) equation for dust acoustic shock waves in a homogeneous system of a magnetized collisionless plasma comprising a four-component dusty plasma with massive, micron-sized, positively, negatively dust grains and non-extensive electrons and ions. The effect of dust viscosity coefficients of charged dusty plasma of opposite polarity and the non-extensive parameters of electrons and ions have been studied. The behavior of the oscillatory and monotonic shock waves in dusty plasma has been investigated. It has been found that the presence of non-extensive parameters significantly modified the basic properties of shock structures in space environments. [ABSTRACT FROM PUBLISHER]

Some of the properties of a nonlinear coherent state associated with the centre of mass motion of trapped atoms are considered. Especially the autocorrelation function, motional quanta number distribution, the phase properties, the Husimi–Kano Q function and the Wigner–Moyal W function of this nonlinear coherent state are discussed. Jumps in the motional quanta distribution function are reported depending on the dependence on the Lamb–Dicke parameters. [ABSTRACT FROM AUTHOR]

New states of electromagnetic field, generalized excited negative binomial states are introduced here. These states interpolate between the superposition of two excited coherent states and number states. The non-classical properties for these states are discussed, such as, second order correlation function, squeezing phenomena [normal squeezing and amplitude squared squeezing], phase properties in Pegg-Barnett formalism and the quasi-probability distribution functions (Q-function and Wigner function). [ABSTRACT FROM AUTHOR]

The odd excited negative binomial states are introduced using the photon creation operator by repeated application on negative binomialstates. These states interpolate between the odd displaced Fock states and the odd excited pure thermal states. In this paper both squeezing phenomena (normal squeezing and amplitude squared squeezing) are discussed. Besides discussion of the Glauber second-order correlation function, investigations are carried out for the quasi-probability distribution functions (Wigner function and Q-function). Finally the Pegg–Barnett phase probability distribution is computed for these states. [ABSTRACT FROM AUTHOR]