This article is dedicated to Claudio Bunster on the occasion of his 60th birthday. It is a great honor to take this opportunity to express my gratitude to him,

In the last few years modified gravity theories have been proposed as extensions of Einstein's theory of gravity. Their main motivation is to explain the latest

Leading theorists share their important insights into the ongoing quest of theoretical physics to find a quantum theory of gravity.

Jacob Bekenstein, an Israeli physicist of the Hebrew University, Jerusalem, planted the seeds of a revolution of our understanding of space-time. Using conserva

Stephen Hawking was widely recognized as the world's best physicist and even the most brilliant man alive–but what if his true talent was self-promotion? When