No one seriously expects to ever throw out Einstein’s equations entirely—except maybe the crackpots who sent unsolicited manuscripts in the mail to science journalists like me. But physicists have good reason to be grumpy about general relativity, despite its success. It doesn’t get along with quantum mechanics, which governs the smallest scales of reality. And it includes a fudge factor that troubled Einstein himself, who added it to account for the accelerating expansion of the universe.
But here in our own solar system, general relativity has proven itself time and time again.