  We describe the critical behavior of electric field-driven (dynamic) Mott
insulator-to-metal transitions in dissipative Fermi and Bose systems in terms
of non-Hermitian Hamiltonians invariant under simultaneous parity (P) and
time-reversal (T) operations. The dynamic Mott transition is identified as a PT
symmetry-breaking phase transition, with the Mott insulating state
corresponding to the regime of unbroken PT symmetry with a real energy
spectrum. We establish that the imaginary part of the Hamiltonian arises from
the combined effects of the driving field and inherent dissipation. We derive
the renormalization and collapse of the Mott gap at the dielectric breakdown
and describe the resulting critical behavior of transport characteristics. The
obtained critical exponent is in an excellent agreement with experimental
findings.
