Description:What happens to the big bang singularity within string theory? Did time have a beginning? These and other pre-eminent questions, whose implications go far beyond the boundaries of physics and even of science, lie at the forefront of todays research in theoretical particle physics and cosmology. Maurizio Gasperini succeeds in this book in drawing a thorough - yet very accessible and captivating - panorama of the various answers that have so far emerged to those basic questions, and of the cosmological observations which may soon allow a stringent test of our most advanced theoretical ideas.