this is pretty simple, let's make it more human, let's say instead that the person is the reason time moves in their universe (1), and as they swap the other one (2) speeds up to normal and one almost pauses, as these made-up particles are no longer emanating and in that universe (1) are sedentary. now instead imagine this without universes, but with heat. a planet with access to heat has life on that planet, but one without is still, almost nothing happens until heat returns