Re: Do people know if nuclei produce EM radiation other than gama rays?

Crysalis,

Nuclei do produce electromagnetic radiation other than gamma rays, if 
properly excited.  The kinds of excitation that occur in nuclear processes 
like fission and fusion involve large energies, so the radiation released 
is at very high frequencies, or gamma rays.  However, the energy levels of 
nuclear states in magnetic fields of 1-10 Tesla are quite close, and the 
radiation in that case is in the radio frequency range.

Nuclear magnetic resonance takes advantage of this fact to derive 
information about the magnetic environment of the nucleus which can then be 
used in a variety of ways.  This technology is used in medical imaging, by 
the oil industry for examining oil-bearing strata, by material scientists 
to learn properties of materials, and by chemists to probe molecular 
structure.

I'm not sure that I understand the second part of your question.  Yes, 
there is less energetic movement that takes place in the nucleus other 
times than in nuclear processes, but this is not responsible for quantum 
mechanics.  Quantum mechanics is the way matter interacts at the level of 
atoms.  Just as there are certain rules about how objects like people, cars 
and planets move and interact, there are rules about how electrons, protons 
and neutrons move and interact.  What is responsible for the relationship 
between Force and acceleration?  It is the way the universe works.