(p, Q) Cosmic Superstrings And Their Nodes Gravitational Radiation

There have been rapid and exciting developments over the last few years on the interface between particle physics and cosmology.Particle physicists pursuing the goal of unification would like to test their theories at energy scales far beyond those available now or in the future in terrestrial accelerators.An obvious place to look is to the very early Universe,where conditions of extreme temperature and density obtained.Meanwhile cosmologists have sought to understand presently observed features of the Universe by tracing their history back to that very early period.The early Universe was an intensely violent environment,so it is not easy to find direct traces of very early events..There are however some special events that may have left traces still visible today,in particular,phase transition.Afert the Big Bang,the Universe underwent a series of phase transiyions.these may have led to the formation of defects.Cosmic strings are line topological defects.Fundamental string,as the fundamental objects of string theory,were very different in many ways from cosmic strings.But this picture has changed in brane world.The recent developmen-t in string theory is the concept of brane inflation.The annihilation of two branes at the end of brane inflation is thought to lead to the formation of cosmic superstrings which can be either fundament F-strings,Dirichlet D-strings,or (p,q)-strings,bound states of the two.This paper aims to calculate and discuss the gravitational radiation emitted by cosmic super-strings. We start with a single string of cases start,given the formula for calculating gravitatio-nal radiation power.On this basis,the system which the three strings form a junction emit the gravitational radiation are discussed in detail,and given the formula for calculating radiation power.