For the totality of all Opposite energies in the universe to ad up to zero the total mass has to be zero. And to conclude this there has to be an equal amount of Normal(Baryonic) Matter and Antimatter.
Obviously we are only made up of and surrounded by Baryonic Matter. Baryonic Matter is one of two possible chiral forms. Your left hand is one chiral form and your right hand is another chiral form. They are mirror images of each other and this introduces the subject of symmetry.
With subatomic particles the chiral opposites create the distinctions of Baryonic and Antimatter. Antimatter particles have a right hand spin and Baryonic particles have a left hand spin. When these opposites contact each other the particles are annihilated.
The universe itself demonstrates a division between its Northern Hemisphere and its Southern Hemisphere. The North is dominated by left hand spiral galaxies and the south by right hand spiral galaxies. Given the mirror inversions of the properties of chiral opposites it can be reasoned through that the Galaxy spin is an indication of whether it’s Baryonic or Antimatter.
Because light is a nonchiral particle, the light emitted from an antimatter Galaxy appears exactly the same as that emitted from a Baryonic Galaxy! The only indication is the spin!
This helps demonstrate how the universe was created by nothing. It was established during the Big Bang by the creation and separation of chirally opposite hydrogen particles. It is maintained by there separation in space and time. The end of physical reality will result in because of the recombination of matter and antimatter.
Something out of nothing, only because of a clever trick!