When I was a child, after bedtime I would often get out of my bed in my pajamas, go to the window and stare at the stars. I had so many questions. How far away were those tiny points of light? Did space go on forever and ever, or was there some end to space,some giant edge? And if so, what lay beyond the edge? Another of my childhood questions: Did time go on forever? I looked at pictures of my parents and grandparents and tried to imagine their parents, and so on, back through the generations, back and back through time. Does time go on forever? Or is there some beginning of time? And if so,what came before? When I grew up, I became a professional astrophysicist. Although I never answered any of these questions, they continued to challenge me, to haunt me, to drive me in my scientific research, to cause me to live on tuna fish and no sleep for days at time while I was obsessed with a science problem.