I don't know much about neutrino. I am not sure if they have a nonzero rest mass just because my knowledge.
Some people say the photons have a non zero rest mass. Here I am sure the photon hasn't its rest mass because it is a wave. If a wave is at rest it disappears.

Neutrino isn't a wave, I think, so it may have a rest mass.
What happens if a neutrino meets an antineutrino ?
Do they annihilate like a particle-antiparticle ?
Do exist the virtual neutrinos-antineutrinos like virtual quarks-antiquarks ?

True - the total sum of energy in the observable universe would be one limit. Another would be expanded to include the potential total universe, well beyond the observable one.

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"Toward no crimes have men shown themselves so cold-bloodedly cruel as in punishing differences of belief." - James Russell Lowell

Another limit could be a Black Hole object.
And also a particles of Cosmic Rays ususaly do not excess an energy of 10^21 eV. A higher energy of the particle causes its decay.

OK, late to tha party again (sorry), but our scattering shows three valence quarks within the proton, not more.

As others have mentioned, you accept equivalent data for atoms having only one nucleus, so why do you doubt it for protons?