[Manal]

I think we are talking about the same Werner Heisenberg's uncertainty principle. But the uncertainty principle is not only about an uncertainty relation between momentum and position. It can also be an uncertainty relation between time and energy.

Heisenberg's uncertainty principle is applicable to all including momentum, position, time and energy. Because for randomness to happen in our realm, everything must work in one instant for the randomness to execute properly. If anything is missing, it cannot be done. A position must be specified as coordinate within the universe for the randomness to take place.

During a precise time interval, it is possible that energy (a.k.a particles) can be temporarily created out of an empty space (a.k.a out of nothing).

"Energy can neither be created nor be destroyed", unless and until if the energy is in the undiscovered form(like dark energy or matter cause we haven't studied them enough).

The idea is that although the total energy of the empty space is zero.

Source

For energy to be converted from one form to another, there must be at least two matter present at the time compatible enough for energy transfer to happen for which can cause creation/destruction of a matter.