ELI5: Explain Like I'm 5

Zero-energy universe

A zero-energy universe means that the amount of energy in the universe is equal to zero. This means that the amount of energy that is released (or output) is the same as the amount of energy that is used up (or input). It might sound strange, but this means that the universe is a balanced place, with all the energy staying in balance with each other. Like two scales that are balanced with the same amount of weights on each side.
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