Science has already answered this question. Before energy and matter there is a field (space/emptiness) which science calls the “Quantum Field”. There is neither any energy nor any matter inside it. Only when this field becomes active do the phenomena called energy, matter, and material forms come into existence.
This raises the question, “Of what kind of activity are we talking about, and how and from what do the energy/matter and material forms come into existence in that field?”
The answer to this question is simple. The energy/matter and material forms are stressed and bestirred particles of that very same field. Those are the active particles of that field. When the field is activated nothing at all has changed regarding the existence of that very field. The particles of that field that have separated themselves from it, and by their movement and work have taken on energetic/material characteristics, have kept all characteristics of that field, only now they are no longer still, but are moving and working.
All this is confirmation of the aforementioned Hegel’s theory, according to which if from something that originally exists appears something else, then this else does not exist, only the original continues to exist: it only changed its form or entered into a different state of itself, so that now it only looks like something else appeared and exists. In this very example, energy/matter and material forms that appear from the quantum field still remain as that same quantum field, only now they are no longer stationary but are moving, performing work, and evolving. Energy/matter and material forms are, therefore, only another aggregated (active) state of that quantum field, having the meaning of consequence, in relation to the still (inactive) state of that field which has the meaning of cause.
This brings us to the conclusion that the energetic/material world and its cause are inseparable, one. In other words, the energetic/material world is both its own cause and consequence. These two are simply two different states of the one and the same – inactive and active. The active state is only the objective, physical manifestation of that field that is achieved by exertion, movement, work, and evolution of the particles of that field. Therefore the only thing that always and only truly (absolutely) exists is that (quantum) field and nothing else. This is also the partial answer to the question what exists, were the natural sciences able to answer this question at all.