New experiments challenge fundamental understanding of electromagnetism

Phys.org ^ | November 28, 2012 | NA

[FredZarguna]

Correction: The biggest variation in nuclear masses atomic weights actually come from averaging isotope species and (to a much smaller extent) differences in binding energy. [Nuclear mass itself only changes as a result of binding energy.]

[grey_whiskers]

QED is fully relativistic. Historically it derived from second quantization of the Dirac equation.

Feh. That's what I get for relying on Feynmans QED: The Strange Theory of Light and Matter (ISBN-10: 0691024170 | ISBN-13: 978-0691024172, $7.77 at Amazon.com) instead of having taken a real course in it.

As far as the Gold, I'll take your word for it: it was an offhand comment during a discussion section after a paper at a long-gone Theoretical Chemistry conference, but it was odd enough that it lodged in the esophagus of my mind.

Incidentally, speaking of the Dirac equation, doesn't it leave room for magnetic monopoles? John Van Vleck would be deeply saddened...

Cheers!

[grey_whiskers]

Thanks for the links. (Sound of grey_whiskers purring LOUDLY.)

I owe you a beer!

g_w

[Vigilantcitizen]

God I love FR...thanks to all.

[FredZarguna]

Incidentally, speaking of the Dirac equation, doesn't it leave room for magnetic monopoles?

Well ... it could, but he never developed a fully formed Hamiltonian that would include magnetic monopoles in his theory of the electron, AFAIK.

The famous Dirac/Magnetic Monopoles thing you're talking about was that he published a symmetrized revision of Maxwell's Equations which included magnetic monopoles complete with a magnetic Gauss's Law and Magnetic displacement currents. The whole deal. The consequences were interesting. But it was purely classical.

[FredZarguna]

The water in a steam turbine isn't really used to "make electricity."

As you correctly point out, all that is required is a conductor moving in an electromagnetic field (specific conductors, such as iron and nickel are not required.) Or [what relativistically amounts to the same thing] a stationary conductor inside a time varying electromagnetic field will also function as a generator.

The expansion of water from the nuclear pile's heat is just a way to move the turbine. That's all. Any way you could convert the heat into some way of moving the conductor through the field works just fine. As it turns out, for many reasons including the enormous amounts available and its low toxicity, water is actually a pretty good fluid to use.