Could the energy produced during matter-antimatter annihilation in the early universe be dark energy? If not, where is that produced energy today?

Astronomers see galaxies flying away from each other faster than expected. Some sort of energy — dubbed “dark energy” because we cannot identify what it is — must be causing this repulsion. We know that dark energy composes an amazing 68 percent of the universe, so it produces an extremely big effect. Normal matter — like stars, gas, and planets — is only 5 percent of the cosmos.

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