Chad Orzel's How to Teach Physics to Your Dog is an absolutely delightful book on many axes: first, its subject matter, quantum physics, is arguably the most mind-bending scientific subject we have; second, the device of the book — a quantum physicist, Orzel, explains quantum physics to Emmy, his cheeky German shepherd — is a hoot, and has the singular advantage of making the mind-bending a little less traumatic when the going gets tough (quantum physics has a certain irreducible complexity that precludes an easy understanding of its implications); finally, third, it is extremely well-written, combining a scientist's rigor and accuracy with a natural raconteur's storytelling skill.
I find quantum physics very difficult to hold in my head. I can understand it while it's being explained, and sometimes for a day or two longer, but then it fizzles away (I find calculus to be of similar character). However, the essentials I've grasped have always come embedded in stories — first in Greg Egan's magnificent debut novel Quarantine and now in How to Teach Physics to Your Dog. The going isn't always smooth or easy, but for me, it has never been less hard!