Yes, Karla knew about relativity without knowing about Einstein. Blame Ender.
"Fortunately, Ben's universe doesn't believe in that nonsense," she said. "Which means you can travel to Saturn for lunch and still be back in time for the last class of the day. Less time than that, if you don't play around, but what's the point of being in a spaceship if you don't play around at least a little?"
Re: Day One: Daytime [Lake Country]
Yes, Karla knew about relativity without knowing about Einstein. Blame Ender.
"Fortunately, Ben's universe doesn't believe in that nonsense," she said. "Which means you can travel to Saturn for lunch and still be back in time for the last class of the day. Less time than that, if you don't play around, but what's the point of being in a spaceship if you don't play around at least a little?"