Hmm ... then why haven't you included the CNB (cosmic neutrino
background)?

As mentioned in other posts, Ross wants the amount of electromagnetic
energy produced as a function of time. So, obviously, emission by
anything which has been heated by electromagnetic radiation shouldn't be=

counted, since that would be counting the corresponding energy twice.
Also, neutrinos can be ignored since a negligible fraction of their
energy is converted to electromagnetic radiation.

Yes, exactly on target. If dust is heated by EM from stars where fusion
was the originator of the energy conversion, then I would need to
subtract off the energy that was absorbed, and add back in the energy
radiated in IR. But those (in steady state) are the same values, though
red shifted wavelengths. So, no point bothering with absorption and re
emission.

[Moderator's note: Right. I read yesterday that about half of stellar
energy is absorbed and re-radiated in the infrared. -P.H.]

As for Cosmic neutrino background, if I understand right, those were
produced during the big bang, prior to launch of CMB. I'm counting
energy production AFTER the CMB was launched. So we go through dark
ages, no energy production, then star formation and the tale begins and
I begin tracking energy production.

Now **IF** there were significant energy transfer from cosmic neutrinos
into the gas and stars, now and or back in early universe, then I'd need
to count that energy. I've assumed that is negligible, as seems to be
confirmed in comment above.

However, I do have a red flag in my brain since so much energy in SNII
comes out in neutrinos. The energy in those supernovae is in part,
energy from neutrinos colliding with the matter of the star, so that
would count. Thugh I'm adding SNII energy which I believe already
includes that quantity.

That said, this thread has wandered off topic me thinks.

rt