It is ten minutes past six by the invisible clock on the wall. The young patents clerk sprawls in his chair, dreaming about time. He is Albert Einstein, and in his dreams he imagines new worlds, in which time can be circular, or flow backwards, or slow down at higher altitudes.

An essential resource for learning about general relativity and much more, from four leading experts Important and useful to every student of relativity, this book is a unique collection of some 475 problems--with solutions--in the fields of special and general relativity, gravitation, relativistic astrophysics, and cosmology. The problems are expressed in broad physical terms to enhance their pertinence to readers with diverse backgrounds. In their solutions, the authors have attempted to convey a mode of approach to these kinds of problems, revealing procedures that can reduce the labor of calculations while avoiding the pitfall of too much or too powerful formalism. Although well suited for individual use, the volume may also be used with one of the modem textbooks in general relativity.

An essential resource for learning about general relativity and much more, from four leading experts Important and useful to every student of relativity, this book is a unique collection of some 475 problems--with solutions--in the fields of special and general relativity, gravitation, relativistic astrophysics, and cosmology. The problems are expressed in broad physical terms to enhance their pertinence to readers with diverse backgrounds. In their solutions, the authors have attempted to convey a mode of approach to these kinds of problems, revealing procedures that can reduce the labor of calculations while avoiding the pitfall of too much or too powerful formalism. Although well suited for individual use, the volume may also be used with one of the modem textbooks in general relativity.

Where the science of black holes, gravitational waves, and time travel will likely lead us, as reported by spacetime's most important theoreticians and observers.

Our minds tell us that some things in the universe must be true. The New Physics tells us that they are not, and in the process, blurs the line between science and science fiction. Here are six accessible essays by those who walk that line, moving ever further out in discovering the patterns of nature, aimed at readers who share their fascination with the deepest mysteries of the universe.

• Richard Price: "An Introduction to Spacetime Physics"
• Stephen Hawking: "Chronology Protection"
• Igor Novikov: "Can We Change the Past?"
• Kip S. Thorne: "Speculations about the Future"
• Timothy Ferris: "On the Popularization of Science"
• Alan Lightman: "The Physicist as Novelist"

"This is story making that lifts the human spirit out of our sometimes petty terrestrial concerns and places us among the stars."—Scientific American

Best-selling author Alan Lightman selects the year’s finest nonfiction as this acclaimed series celebrates its fifteenth year. He has chosen a diverse, very personal collection that celebrates the essay as an independent genre unlike any other. This year’s pieces embrace stylistic freedom and strong opinions and afford the reader a fascinating view of the writer’s mind as it struggles with truth, memory, and experience. Featured writers include Jamaica Kincaid, Edward Hoagland, Cynthia Ozick, Mary Gordon, Edwidge Danticat, and others.