According to Quantum Mechanics, sub-atomic particles called "virtual" particles constantly pop in and out of existence in space-time everywhere.
They are not directly detectable as they appear and disappear extremely fast.
Is it possible that they always get created as pairs of particle-antiparticle?
And if so, is it possible one particle in each pair always has negative mass/energy so that when they destroy each other back,
they completely cancel out and so they do not create (gamma) photons, unlike what happens when "real" particle-antiparticle pairs destroy each other?