Does everything in the universe consist of energy?

Yes, because we are allowed to use Einstein's famous equation,

Energy  =   mass x  (speed of light)

to convert any scrap of matter into an equivalent quantity of energy. So, at its essence, everything is made of energy, its just that this energy takes different forms in the physical world. In fact, because protons are made of quarks and we know the mass of a quark, we discover that over 99 percent of the mass of the proton is locked up in the energy of the field that holds the quarks together inside the proton! This energy of the 'gluon' field appears as real mass to the outside world. What this also means is that 99 percent of your mass is in the form of field energy alone!
Copyright 1997 Dr. Sten Odenwald
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