  Conditions at which a quasi-one-dimensional (1D) electron system can be
considered as a quantum liquid of impenetrable charged particles are
theoretically analyzed. In the presence of an inert, neutralizing background, a
motion of impenetrable electrons is shown to expose a positive charge,
resulting in an effective mutual attraction of infinite range. As a result, all
electrons are involved in the long-range pairing. A model of spinless fermions
with infinitesimal attraction of infinite range is proposed to describe the
excitation spectrum and the superconducting gap in low-density 1D electron
channels. In contrast with the conventional theory, the energy gap does not
contain exponentially small factors. It depends mostly on the Coulombic
parameters of the system, which guides practical aspects of high-temperature
superconductivity.
