I am trying to remember the title of a novel with the following plot points:
A spacecraft is sent via supposedly instantaneous travel to a distant system, but they return 1,000 or 2,000 years later (this is the backstory, it's outlined at the beginning). They thought they were getting a hyperdrive; they really just got a sort-of-relativistic one.
The planet they travel to is inhabited by a race of furry beings who are "primitive" but have a philosophical outlook that allowed the humans to improve their pseudo-hyperdrive
When the explorers return there's some political intrigue involving the people of Earth
I recall a line from the book where the explorers are talking with a dude who is their orientation officer of sorts, and he says that "well, yes, we've discovered everything" about physics, or something like
I think the author was one of the bigger names but I can't recall
This mayn't be much to go on. But I can describe the cover: it had one of the furry beings on it, looking like a werewolf or something, in the corridor of a spacecraft.