Remember that the laws of physics tell us what is possible, not what is practical for humans at this point in time. The physics of time travel is ... even proposed using wormholes to connect ...

Carl Sagan, the astronomer, Pulitzer Prize-winning author, and legendary popularizer of science, gave this interview during the making of "Time Travel." True to form, he discusses arcane aspects ...

if you go through this tunnel — through this wormhole — you'll go from one moment in time to a different moment in time. Go one way, you'll travel to the past, the other way, travel to the future.