A great book about the various tests that Einstein's General Relativity (GR) have been put through since it was proposed. Spoiler alert, GR has passed all the tests so far, while alternative theories of gravity have not. A follow up to one of the author's earlier book, "Was Einstein Right?", this book covers much of the same ground, but updates it with some of the latest experiments that have been performed to verify the predictions of GR.

Many aspects of GR, from the effects of gravity on space-time, to how black holes twist and turn space-time and light, are covered in the book, along with historical and current experiments done to prove (or disprove) GR. Some of the tests involving astrophysics (like stars orbiting black holes, imaging black holes and gravitational waves) are the latest, and most dramatic, examples of GR in action and are still ongoing. The hope is that in such the extreme environments, deviations from the predictions of GR will appear, pointing the way to new physics and perhaps unifying quantum theory with GR.

But don't hold your breath; odds are GR will still work, and the hunt to find yet more precise tests of GR will have to continue for some time to come.