Coming back to the OP, I find I still have a few unanswered questions.
1. Why does Siegel seem to regard curved spacetime as something, but flat spacetime as something? Isn’t spacetime is something, whether curved or flat?
2. Doesn’t the Casimir effect work precisely because there is something between the plates?
3. “And if you start with enough energy, you can take all of the real matter and antimatter pairs that exist, and create more matter than antimatter, giving us a Universe where we have something, today, rather than nothing.”
If we are starting with “enough energy”, how is this starting with nothing?
4. “we definitely can get something for nothing; quantum field theory not only allows it, it demands it.”
If we start with quantum field theory, isn’t that a theory of something?
