Double-bounce domain-wall in Einstein-Yang-Mills-Scalar black holes

We find Einstein-Yang-Mills (EYM) black hole solutions endowed with massless scalar hair in the presence of a potential $V\left(\phi \right)$ as function of the scalar field $\phi$. Choosing $V\left(\phi \right) =$constant (or zero) sets the scalar field to vanish leaving us with the EYM black holes. Our class of black hole solutions is new so that they do not asymptote in general to any known limits. Particular case is given, however, which admits an asymptotically anti de Sitter limit in $6-$dimensional spacetime. The role of the potential $V\left(\phi \right)$ in making double bounces (i.e. both a minimum and maximum radii) on a Domain Wall (DW) universe is highlighted.Comment: 9 pages, 1 figure, final version for publication in EPJ

Ground State H-Atom in Born-Infeld Theory

Within the context of Born-Infeld (BI) nonlinear electrodynamics (NED) we revisit the non-relativistic, spinless H-atom. The pair potential computed from the Born-Infeld equations is approximated by the Morse type potential with remarkable fit over the critical region where the convergence of both the short and long distance expansions slows down dramatically. The Morse potential is employed to determine both the ground state energy of the electron and the BI parameter.Comment: 4 pages, 1 figure, final version to appear in Foundation of Physic

Constant curvature f(R) gravity minimally coupled with Yang-Mills field

We consider the particular class of f(R) gravities minimally coupled with Yang - Mills (YM) field in which the Ricci scalar =R_{0}= constant in all dimensions d\geq4. Even in this restricted class the spacetime has unlimited scopes determined by an equation of state of the form P_{eff}={\omega}{\rho}. Depending on the distance from the origin (or horizon of a black hole) the state function {\omega}(r) takes different values. It is observed that {\omega}\rightarrow(1/3) (the ultra relativistic case in 4 - dimensions) and {\omega}\rightarrow-1 (the cosmological constant) are the limiting values of our state function {\omega}(r) in a spacetime centered by a black hole. This suggests that having a constant {\omega} throughout spacetime around a charged black hole in f(R) gravity with constant scalar curvature is a myth.Comment: 12 pages 2 figures, Some references and 2 figures are added with minor changes. Final version for publication in European Physical Journal

Effect of Silver Ions on Ethylene Metabolism of Mustard Grown Under Irrigated and Non- irrigated Conditions

A field experiment was conducted during the winter season of 2004-2005 at the Experimental farm of Aligarh Muslim University, Aligarh, India on mustard (Brassica juncea L. Czen and Coss, cultivar Alankar) under irrigated and non -irrigated  conditions to evaluate the application of 0  and 200 µl/L  ethrel (E200) or 1 mM silver thiosulphate (S) at flowering stage along with a basal  uniform application of 80 kg N ha-1 on leaf area, plant dry mass, net photosynthetic rate and seed yield. Silver thoisulphate, which inhibits the physiological action of ethylene was used in the experiment with ethrel. Ethrel is a source of ethylene and its effects are manifested through physiological action of ethylene. Ethrel 200 µl/L (E200) treatment enhanced leaf area, net photosynthetic rate, plant dry mass and seed yield by 10.6, 9.1, 7.7 and 11.6% over S treatment. So silver thiosulphate (S) reduces the physiological action of ethrel (source of ethylene) in this study. This clearly indicates that silver ions used in this experiment in the form of silver thiosulphate inhibits the action of ethylene metabolism in mustard

Improved fisheries productivity and management in tropical reservoirs

“Improved fisheries productivity and management in tropical reservoirs” The objective of the project was to contribute to the current research on reservoirs enhancement fisheries in tropical countries through the implementation of a series of action-research activities implemented in two small reservoirs in the Indo-Gangetic basin in India, and two very large reservoirs in Africa, the Lake Nasser (Egypt), and the Volta Lake (Ghana). Socio-institutional analyses were also conducted in these reservoirs to improve our knowledge regarding some of the main social processes that influence reservoir productivity. Overall the results of the project stress that while the natural biophysical constraints of the reservoirs are important in defining the ecological production processes, it is the socio-economic settings characterizing the community/societies around the reservoirs that eventually shape the human production enhancement possibilities

Chaos in a double driven dissipative nonlinear oscillator

We propose an anharmonic oscillator driven by two periodic forces of different frequencies as a new time-dependent model for investigating quantum dissipative chaos. Our analysis is done in the frame of statistical ensemble of quantum trajectories in quantum state diffusion approach. Quantum dynamical manifestation of chaotic behavior, including the emergence of chaos, properties of strange attractors, and quantum entanglement are studied by numerical simulation of ensemble averaged Wigner function and von Neumann entropy.Comment: 9 pages, 18 figure

Thermodynamics of Rotating Black Branes in Gauss-Bonnet-nonlinear Maxwell Gravity

We consider the Gauss-Bonnet gravity in the presence of a new class of nonlinear electromagnetic field, namely, power Maxwell invariant. By use of a suitable transformation, we obtain a class of real rotating solutions with $k$ rotation parameters and investigate some properties of the solutions such as existence of singularity(ies) and asymptotic behavior of them. Also, we calculate the finite action, thermodynamic and conserved quantities of the solutions and using the the Smarr-type formula to check the first law of thermodynamics.Comment: 15 page

Equation of motion of a classical scalar field with back reaction of produced particles

In the one-loop approximation we derive the equation of motion for a classical scalar field \phi_c (t) with the back reaction of particle production included. Renormalization of mass and couplings of \phi_c is done explicitly. The equation is non-local in time, but can easily be treated perturbatively or numerically. For the weak trilinear coupling of the external field to the produced particles, the new equation gives the same solution as the familiar one with the \Gamma \phi_c term. For a stronger coupling and other types of couplings the results are significantly different. The equation can be applied to the universe heating by the inflaton decay and to spontaneous baryogenesis.Comment: 29 pages, 16 figures, subm to NP