  Despite decades-long efforts, magnetic monopoles were never found as
elementary particles. Monopoles and associated currents were directly measured
in experiments and identified as topological quasiparticle excitations in
emergent condensed matter systems. These monopoles and the related
electric-magnetic symmetry were restricted to classical electrodynamics, with
monopoles behaving as classical particles. Here we show that the
electric-magnetic symmetry is most fundamental and extends to full quantum
behavior. We demonstrate that at low temperatures magnetic monopoles can form a
quantum Bose condensate dual to the charge Cooper pair condensate in
superconductors. The monopole Bose condensate manifests as a superinsulating
state with infinite resistance, dual to superconductivity. Monopole
supercurrents result in the electric analog of the Meissner effect and lead to
linear confinement of Cooper pairs by Polyakov electric strings in analogy to
quarks in hadrons.
