In Java, are static class members shared among programs?

I imagine that no, they aren't, because every process has its own memory space, of course.

But how does the whole JVM thing actually work? Is there a separate JVM in a separate process for every Java program that I launch? Do Java programs running in a system share anything at all? Are there differences between OSs and JVM implementations? Can I make programs share variables (i. e. directly through the JVM rather than the usual IPC mechanisms)? Are there more exotic one-process JVMs for special purposes?

Generally, what are recommendable reads about the guts of JVMs? The spec? The source code of some implementation? Websites? Books?