  We formulate the problem of unconventional $d-$wave superconductivity, with
phase fluctuations, pseudogap phenomenon, and local Cooper pairs, in terms of a
synchronization problem in random, quantum dissipative, elasto-nuclear
oscillator networks. The nodes of the network correspond to {\it localized,
collective quadrupolar vibrations} of nuclei-like, elastic inhomogeneities
embedded in a dissipative medium. Electrons interacting with such vibrations
form local Cooper pairs, with a superfluid $d-$wave pseudogap $\Delta_{PG}$,
due to an effective, short range attractive interaction of $d_{x^2-y^2}$
character. Phase coherent, bulk superconductivity, with a $d-$wave gap
$\Delta$, is stabilized when the oscillator network is asymptotically entangled
in a nearly decoherence-free environment. Phase coherence will in turn be
destroyed, at $T_c$, when the thermal noise becomes comparable to the coupling
between oscillators, the superfluid density $K$. The $2\Delta/k_B T_c$ ratio is
a function of Kuramoto's order parameter, $r=\sqrt{1-K_c/K}$, for the loss of
synchronization at $K_c$, and is much larger than the nonuniversal
$2\Delta_{PG}/k_B T^*$ ratio, where $T^*$ is the temperature at which
$\Delta_{PG}$ is completely destroyed by thermal fluctuations. We discuss our
findings in connection to the available data for various unconventionally
high-temperature superconductors.
