: I have been told that mass cannot truly be converted to : energy. Is this true?

When we speak energy, we speak matter-energy, always. Of cource we can speak non-matter-energy, but we cannot say, how non-matter-energy, works, because we cannot sense it.

Matter-energy, is always, sama thing, but we use words, to describe, it.

Matter means, that something exist, is, like trees, planets, cells, 'genes', 'atoms', etc,

Energy means, that matter has some 'properties', and this 'properties' has 'mind' to move.

Energy is always, matter-moving-process-result. Like, electric energy, or radiowaves, or etc.

Matter-and energy, is always same,

"matter-energy".

electric-matter-energy water-matter-energy wind-matter-energy wind-matter-electric-energy etc.

Non-matter-energy, is that, what we cannot sense, or view, or make words, or calculate.

Every our measuring equipments, measure always "matter-energy".

We can separate mass-and energy, only at paper, like mathematics formulaes, or , words, like this. matter and energy, but at nature, where we live,. matter-energy, is always same, one.

But.

How matter born?, and why?, i dont know? Answer of this is 'non-matter'.