TAPA DURA , LIBRO USADO, RECUERDA QUE EL 10% DE ESTA VENTA COLABORA CON FUNDACIONES QUE FOMENTAN LA LECTURA EN ZONAS VULNERABLES. Along with Caltech physicist Mlodinow (The Drunkard's Walk), University of Cambridge cosmologist Hawking (A Brief History of Time) deftly mixes cutting-edge physics to answer three key questions-- Why is there something rather than nothing? Why do we exist? Why this particular set of laws and not some other?-- and explains that scientists are approaching what is called "M-theory," a collection of overlapping theories (including string theory) that fill in many (but not all) the blank spots in quantum physics. This collection is known as the "Grand Unified Field Theories."