The origin of DNA—precisely how and where was the first DNA formed?

Can we live forever? Can genetic engineering stop the aging process?

What happened before the big bang? Did time suddenly spring into existence, or was there a multiverse of universes?

How will our universe die? In fire or ice? A Big Crunch or Big Freeze?

Is there a theory of everything, a single theory which can explain everything from the big bang, black holes, to the visible universe?

Can a machine think? Can we create silicon consciousness?

Is there intelligent life in outer space?

Is it possible to reach the nearby stars via starships?