We already know that the total energy of the universe is zero. We also know that matter and energy are equivalent. From these can we conclude that the total matter of the universe is also zero? Scientist Vector J Stenger thought so. Here is a quote:
‘E=mc2 says matter and energy are the same entity. Since E=0, the total matter of the universe is zero. Zero does not have to come from anything.
‘Now, if by matter you just mean the equivalent of rest energy, then that came from gravitational energy during the expansion in the early universe.’