Global famines have dropped the population to 1 billion people and global civilization has collapsed. In an effort to save future civilization some time, you want to provide some information to kick start civilization's regrowth.
We assume a knowledge and tech level equivalent to Europe in 1800. Any math, general knowledge or tech that we had in 1800, they will have access to. Further, the future reader is fluent in one of the languages that these books are written in.
You have to choose exactly three books on physics
(And only about physics. Other topics will be covered in other questions.) By virtue of a print-on-demand press and a generous internet connection (and minimal scruples about copyright law), you can get your hands on the text and diagrams of most any book/article in existence.
The best book choices will:
- Give future generations stronger pointers for where to go looking for further knowledge. For example, Newton's Philosophiæ Naturalis Principia Mathematica codified the laws of motion and kicked off significant research into physics. Knowing where to look helps a lot. (Side note, I've tried to read Principia and it's completely impenetrable.)
- Save them some the trial and error of fumbling around on their own. It's well known that once something has been shown to be possible, it can be rapidly imitated.
- Need not be all immediately useful. It's just fine to have one book be useful for 50 years then the second book suddenly becomes far more useful. And so on with the third.
Printing off all the physics articles on Wikipedia or arxiv.org/physics won't satisfy because...reasons. Only actual books will satisfy.
Preserving the books is a solved problem so you don't need to worry about it. You're responsible only for picking the three books. These won't be electronic copies as we can't be assured that someone will have access to electronics.
Note to responders: While it's true that three books is arbitrary, the number was chosen as it forces hard choices about which books are really worthy. There are two extremes at play: the utterly mundane, "give them normal undergraduate textbooks" and "compress an entire field down to three books". The first isn't noteworthy, while the second is impossible. Try to push your selection of books further towards the highly comprehensible master-works of the field.
This question is a part of the Three Books series. It will grow to cover many and diverse topics, thus, the fairly narrow scope.
While we can be reasonably sure that these three books will be found together, we can't be sure that they will be found with any other sets of books.