[Redcitizen]

But if it works, why not go back ten years to now and give the information on how to build it thus sparing ten years of research to create it?

[14themunny]

"But if it works, why not go back ten years to now and give the information on how to build it thus sparing ten years of research to create it?"

I wish it were that simple...

"—"it can't be used to travel to a time before the time machine was constructed."