“…In particular, examinations of the changes in the positron spectra when switching from subcritical to supercritical Cm − U 92þ collisions are very promising for this purpose. The experimental study of the proposed scenarios, which seems feasible with the future facilities at GSI/FAIR [46][47][48], HIAF [49], and NICA [50], would either prove the vacuum decay in the supercritical Coulomb field or lead to discovery of a new physics, which is beyond the presently used QED formalism.…”