After reading every above statement, I am now more confident and convinved of my theory.
Succintly, my theory is that:-
Antimatter: has antigravity; is dark energy ; can never be annihilated in the future; when annihilated, changes to dark matter which has gravity
Matter: has gravity; is normal matter; can never be annihilated in the future; when annihilated changes to electromagnetic radiation/light which does not have gravity.
The following words "and with the expansion of the Universe probably never will" can be said to be wrong if there were no dark energy, the energy that expands the universe. Now, if my theory is wrong, the above specially mentioned words will also be wrong. As (Okay, now I understand what you meant by "succintly", Cat), Antimatter has antigravity according to my theory, the antimatter that had not been annihilated during the beginning of the Universe can never be annihilated in the future. (These statements are based on Cat's posts in the twin body theory forum)"If matter and antimatter were symmetric, then how do we exist?"
Easy question. The Universe is so 'large' (even call it endless ) and so extensive in 'time' (some call it endless) that each unit or sub-unit or sub-sub unit of matter has not yet nullified each unit or sub-unit or sub-sub unit of anti-matter and with the expansion of the Universe probably never will.
Succintly, my theory is that:-
Antimatter: has antigravity; is dark energy ; can never be annihilated in the future; when annihilated, changes to dark matter which has gravity
Matter: has gravity; is normal matter; can never be annihilated in the future; when annihilated changes to electromagnetic radiation/light which does not have gravity.