While today"s image may look like a scene from the "Doctor Who" TV show, it actually shows workers maintaining Big Ben"s clock face. But like the Doctor, the show"s main character, today we"re all time travelers. This morning we fell back (or will fall back for night owls and insomniacs reading this before 2 AM) in time an hour for the end of daylight saving time. And like changes to "Doctor Who," this shift isn"t without controversy. Since the 1970s, many studies have tried to quantify the advantages or disadvantages that come with falling back and springing forward, but as yet there"s no definitive answer.