electromagnetic radiation - Continuous vs. Discrete Spectra in various materials

I read that the reason solids emit continuous spectra is that they don't have time to let their electrons decay-they are too close together. Given that electrons decay on the order of 100 nanoseconds I find this difficult to believe. Also, do electromagnetic waves move the electrons, or the atom, or both? If it is simply exciting the electrons, I don't know why is should also give way to the vibration of the atoms. If it does give way to vibration, then shouldn't gases also give way to continuous spectra?

Answer

These statements show great confusion in the concepts of modern physics.

I read that the reason solids emit continuous spectra is that they don't have time to let their electrons decay-they are too close together.

It is confusing to be talking of time with respect to emissions and you give no link.

To start with at the atomic level, in any phase of matter, gas,liquid,solid,plasma , the framework is quantum mechanics. Quantum mechanics works with potentials of the electrons in the atom, and between atoms/molecules and with the intermolecular van der Waals forces in the lattice of solids.

Gas atomic spectra come from excitations of the electrons and possible vibrational transitions of the atoms as they move in the gas scattering off each other. Note the high excitation values needed from the power source, 5000 volts.

High excitation values are needed to see emission spectra from solids too, but long before the input energy reaches the atomic level energies needed to excite the electronic atomic orbits the intermolecular energy lines become excited. Iron in the forge glows, mostly in the infrared. The radiation appears continuous to the eye and the instruments because there are very many energy levels between molecules overlapping in value due to the complexity of the ~10^23 molecules per mole in matter, all compressed in " touch" densely with neighbors. It is effectively the black body radiation that dominates from solids. This shows the quantum nature not in individual lines but in the avoidance of the ultraviolet catastrophe, where the model is of harmonic oscillators changing energy levels.

Given that electrons decay on the order of 100 nanoseconds

Electrons do not decay. Decay can be attributed to the de-excitation of the atom by emission or the de-excitation of the lattice in solids . The time of de-excitation depends on the energy and conforms with the heisenberg uncertainty principle bounds.

Also, do electromagnetic waves move the electrons, or the atom, or both?

Both. When the frequency is right for the energy level an electron can be kicked up, or a molecule go to a higher rotational level, or an ensemble of molecules go to a higher level.

If it is simply exciting the electrons, I don't know why is should also give way to the vibration of the atoms.

see above

If it does give way to vibration, then shouldn't gases also give way to continuous spectra?

If gases are molecular, they have molecular vibrational levels, but the frequencies will not be optical as these levels are of much softer energy. Matter in the gas phase is very diffuse and inter molecular forces exist transiently, when they scatter and transfer kinetic energy to molecular levels which then decay to ground state.

The appearance of continuum to the eye can be obtained as with mercury vapor lamps. The lines are discrete.