Deep Universe: Saas-Fee Advanced Course 23. Lecture Notes 1993. Swiss Society for Astrophysics and Astronomy

Cosmology has not been the subject matter of a Saas-Fee Advanced Course since 1978. That occasion was the memorable course entitled Observational Cosmologyy with lecturers J.E. Gunn, M.S. Longair, and M.J. Rees. A new course on cosmology seemed overdue, and we subsequently planned and or­ ganized, with the endorsement of the Swiss Society of Astrophysics and As­ tronomy, the present, 23"^^ Saas-Fee Advanced Course. Probing (drilling) the Universe to greatest depths, in terms of diffuse radiation and discrete objects, with all consequences for our understanding of cosmic evolution, was meant to be the unifying aspect of this course. Hence the title The Deep Universe. We are very happy to have won such competent and brilliant scientists as lecturers. Malcolm Longair - Saas-Fee lecturer for the second time! - lectured on cosmological background radiation ("The Physics of Background Radia­ tion"); Richard Kron on observations of extremely distant galaxies ("Evo­ lution in the Galaxy Population"); while the Grand Master of Cosmology, Allan Sandage, provided the fundaments of it all, also in a historical sense ("Practical Cosmology: Inventing the Past"). The course took place from 29 March to 3 April, 1993, in Les Diablerets, with around 90 participants. The format was as usual, every lecturer giving 9 or 10 lectures of 45 minutes.

This book provides a first-hand account of modern cosmology, written by three celebrated astronomers renowned for their excellence in both research and teaching. The central theme of the book, the deep Universe, is approached in three truly complementary ways: as a coherent and smooth theory embracing the evolution of the Universe from its original radiations emerging from the hot Big Bang to the present structures of matter; as a meandering, rough road paved by our observations of stars, galaxies, and clusters; and in terms of how these approaches have been gradually developed and intertwined in the historical process that led to the modern science of cosmology. The book is written for graduate students in astrophysics but is also of interest to professional astronomers and particle physicists.