Probability for Primordial Black Holes in Multidimensional Universe with Nonlinear Scalar Curvature Terms

We investigate multi-dimensional universe with nonlinear scalar curvature terms to evaluate the probability of creation of primordial black holes. For this we obtain Euclidean instanton solution in two different topologies: (a) $S^{D-1}$ - topology which does not accommodate primordial black holes and (b) $S^1\times S^{D-2}$-topology which accommodates a pair of black holes. The probability for quantum creation of an inflationary universe with a pair of black holes has been evaluated assuming a gravitational action which is described by a polynomial function of scalar curvature with or without a cosmological constant ($\Lambda$) using the framework of semiclassical approximation of Hartle-Hawking boundary conditions. We discuss here a class of new gravitational instantons solution in the $R^4$-theory which are relevant for cosmological model building.Comment: 18 pages, no figure. accepted in Phys. Rev.

Adolescent pregnancy: an overview

A pregnancy can take place at any time before or after puberty. Adolescent pregnancy is defined as pregnancy under the age of 20 years. It is a problem in both developed and developing country. It raises various human right issues i.e. an adolescent pregnant girl is forced to leave school, depriving her right to education; she is prevented from using any contraception or reproductive health related information, so she is also denied her right to health. As many adolescents are neither physically nor psychologically ready for pregnancy or childbirth, this reproductive event makes them more vulnerable to complications resulting in devastating health consequences for them. Early drop out from the school and health problem jeopardize their income-earning potential

Substitution of scarce metals with special reference of standardisation in India

IN THE context of present economic conditions of the country, the substitution of' scarce metals has assumed great importance. The foreign exchange position of the country has compelled the Government to think of various ways for the conservation of foreign exchange. It is, therefore, important that use of scarce metals should be minimised as far as possible. Considerable amount of foreign exchange is drained out annually for the import of various scarce metals for the need of industries. Most of the non-ferrous metals are scarce in India. The position varies from quite abundance in case of aluminium to deficiency in the case of copper, lead and zinc and a total absence in the case of nickel and tin