Add Yahoo as a preferred source to see more of our stories on Google. Time dilation. The fifth dimension. Gravity's ability to transcend time and space. Yep, if you watched Christopher Nolan's sci-fi ...

Time dilation. The fifth dimension. Gravity's ability to transcend time and space. Yep, if you watched Christopher Nolan's sci-fi epic "Interstellar" and ended up with more questions than answers, you ...