Hi Blacknad,
" ... is there any other way to get at the truth?" I believe so and in several ways. One of these is through simple experience. Let me explain. At one time no human could fly. At the time it could well have been said that humans did not have what it takes to "Really Know" anything about flying. These days we fly all the time. The only way that one can not "Really Know" is if one doesn't care about it. when aviation became practical in the 20th century many, those who cared, came to "Really Know" about flying.
I think that something like this is happening right now in terms of atomic systems and the other things that concern quantum theory. Bohr, Sommerfeld and all the early pioneers of QT felt that we would never "Really Know" what is going on at the small scale. Well I loog around me and see electrical engineers working small with small numbers of atoms to make integrated circuits and such. I have scientific colleagues that work with single atoms, molecules, minute scrapes of energy and time. When we "shoot the breeze" about all this, we are discussing common experience. While I am hard pressed to explain anything about without a pile of math, I, nevertheless, feel comfortable working with it. The point is that as we work with something, i.e., gain experience, we begin to "Really Know" it.
Another method is familiar from differential equations: take a "wild a$$ guess" and then check it. Many of the early workers in QT, after Bohr but before Schrodinger/Heisenberg, used this method. This is especially true in spectroscopy where many formulae were simply guessed. Goudsmit was really good at this.(see:
http://www.lorentz.leidenuniv.nl/history/spin/goudsmit.html )
There is also the old standby, i.e., the unexpected breakthrough. Such events can make a big change in the picture.
"... the creation of something out of nothing ..." begs the question. Sounds like magic and for all I know that might be the ultimate answer. As a scientist though I seek rational explanations of everything. I don't have all the explanations I would like, but I do have a firm and perhaps irrational belief that they are to be had. I'll be damned if I'm the first to give up the side.
BTW a photon has energy equal to Planck's constant time the frequency (E = h nu) and its momentum is just the energy divided by the speed of light (p = E/c.)
Also I was not actually bored at the lecture I mentioned. Andrei Linde was speaking on the begining and fate of the cosmos. The guy is a brilliant cosmologist, good teacher and a decent human being etc. However, he is Russian and when he gets wound up it sounds like he has golf balls stuffed in his cheeks. Anyway it was all old news and the real deal was about the 1st International GLAST Symposium. GLAST is a big gamma ray space telescope that is set to launch Nov. 15, 2007. Now that prelaunch prep and testing is underway it is time to think about science again. (The best part was the meet and greet before and a couple of free beers after helped a lot! This is also why I'm sitting around doing long posts instead of doing something constructive!!!)
The astronomers and especially the cosmologist are champing at the bit. GLAST is also a big whoop in the high energy physics game as well. You see, particle accelerators are nearly as big as they can get in practical terms. If you want the really big energies you need to look up.
Dr. R.