Tufts/CfA/MIT Cosmology Seminar, at Tufts: Julian Borrill, Dartmouth College Title: How Long Is A Piece Of String? Abstract: Cosmic strings formed at a phase transition in the very early history of the universe may be the source of the primordial density perturbations needed to seed large scale structure formation and seen on the microwave sky by COBE. Assessing the viability of such models requires a knowledge of the initial distribution of strings, typically gained from Monte Carlo computer simulations of their formation. Having reviewed the strengths and limitations of the standard algorithm I present the intriguing results of a new, lattice-free, approach.