The ‘opposite’ of a black hole is a ‘white hole’.
If you look just right, you will find a naturally occurring form of a white hole…
This is provided by a mother which feeds her child a substance referred to as ‘breast milk’.
While a black hole tends to break constituent matter and mass (not the same) into the constituent atoms and then energy, through a process similar to digestion, the white hole tends to do just the opposite – form mass and matter in a conversion process from energy.
Energy which incidentally can be accumulated from any potential source.
Makes it pretty obvious why children grow so radically fast.