GALAXY FORMATION FROM KINKY COSMIC STRINGS

We show that the discontinuities (known as "kinks") which are produced whenever cosmic strings interact with each other play an important role in the evolution of cosmic string networks. We argue that there is no physical mechanism that can prevent the build-up of kinks on the long strings, and we show that the build-up of kinks on the long strings prevents the formation of significant numbers of large stable loops. This means that the dominant density fluctuations from cosmic strings are the sheetlike wakes which form in the path of the long strings contrary to the assumptions of the "old" string-induced galaxy formation scenario in which stable loops caused the dominant perturbations. At present, galaxy and large-scale structure formation with cosmic strings is essentially unexplored, but there is some hope that strings might provide a natural explanation of the "sheetlike" nature of galaxy clustering.