The articles collected in this volume cover topics ranging from Planck-scale physics to galaxy clustering. They deal with various new ideas from cosmology, astrophysics and particle physics that might lead to a better understanding of our physical universe. Among the topics covered are inflationary models, nucleosynthesis, dark matter, large-scale clustering, cosmic microwave background radiations and more. The book addresses researchers but it also gives a good overview of the subject for graduate students in astrophysics and particle physics.