Do it yourself is the main motto of physics. Not only is it fun to do so, but also it means that you don't have to believe what I say: you can go and check everything. And you should. Admittedly, it is a bit difficult to build your own particle accelerator and hunt for the Higgs boson, but throughout this book I have mentioned many things which you can verify straight away.

For those things where verification is a little more difficult, such as measuring the charge of the quarks, there is ‘the literature’. This refers to a cubic kilometre or so of physics reference material which has accumulated over the course of the centuries. By reading that, you can find out what has been done in the whole field.

Because there's so much of it, it is absolutely impossible (and indeed unnecessary) to check it all out. A good way to start would be to attend introductory physics lectures, but if you want to stay home I can suggest the following course of action: on the following pages I have listed the most essential literature which I have used in my work on quantum mechanics. I will sketch a possible path through that mound of learnedness. If you follow that path, or something like it, you'll deepen and extend your physics knowledge immensely.