  The interplay of quantum fluctuations and dissipation in chains of mesoscopic
superconducting grains is analyzed, and the results are also applied to
nanowires. It is shown that in 1-d arrays of resistively shunted Josephson
junctions, the superconducting-normal charge relaxation within the grains plays
an important role. At zero temperature, two superconducting phases can exist,
depending primarily on the strength of the dissipation. In the fully
superconducting phase (FSC), each grain acts superconducting, and the coupling
to the dissipative conduction is important. In the SC* phase, the dissipation
is irrelevant at long wavelengths. The phase transitions between these two
superconducting phases and the normal metallic phase may be either local or
global, and possess rich and complex critical properties. These are inferred
from both weak and strong coupling renormalization group analyses. At
intermediate temperatures, near either superconductor-to-normal phase
transition, there are regimes of super-metallic behavior, in which the
resistivity first decreases gradually with decreasing temperature before
eventually increasing as temperature is lowered further. The results on chains
of Josephson junctions are extended to continuous superconducting nanowires and
the subtle issue of whether these can exhibit an FSC phase is considered.
Potential relevance to superconductor-metal transitions in other systems is
also discussed.
