It is when there are 1 billion anti-matter particles for every 1 billion and 1 matter particles.The as·ter·isk is traditionally used to conceptually connect two things that in print are separated.
Your disconnected asterisk is a puzzle.
And while I both welcome and vehemently endorse your mention of natural law, I'm not aware of any definitive scientific tie of big bang to known physics. Nothing is not an explosive.