First off, science is logic plus evidences.
Without the evidences, the explanations is theoretical, and therefore not a “scientific theory”. A scientific theory has to followed the process of scientific method, which mean verification, and which mean...
OBSERVATION
TESTINGS
EVIDENCES
Science 101, godnotgod.
Science don’t relied on logic alone.
Theoretical physics relied on conceptual models, mixed with solving equations. Hence, the solution in theoretical physics is abstract, not on verifiable evidences.
The fields in theoretical physics, eg superstring theory (and supersymmetry), multiverse models, oscillating universe model, etc, are so untestable, therefore are not accepted as scientific theory.
Second.
You are ignoring that most particles, not including gluons and photons have masses.
The energy come from mass of the particle. You as a person, contained many different types of molecules and compounds, which when broken down further, a whole bunch of different atoms, mostly of oxygen, hydrogen, carbon and nitrogen, hence you have both mass and energy.
Matters, meaning all those atoms, and smaller particles, have two properties, mass and energy, which are related.
You have potential energy, when you are at rest, but once you start doing work, the store energy turned into kinetic energy, which means the energy is the measurement of work done.
Mass is what give object or a person - volume, density and shape.
And whenever you calculate energy, except for gluons and photons, be that formula of classical energy (with unit in joules) or that of Einstein’s mass-energy equivalence equation, mass is involved to find the energy.
You keep ignoring mass, which is real.
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