  Isothermal simulational data for the 3D Edwards-Anderson spin glass are
collected at several temperatures below $T_{\rm c}$ and, in analogy with a
recent model of dense colloidal suspensions,interpreted in terms of clusters of
contiguous spins overturned by quakes, non-equilibrium events linked to record
sized energy fluctuations. We show numerically that, to a good approximation,
these quakes are statistically independent and constitute a Poisson process
whose average grows logarithmically in time. The overturned clusters are local
projections on one of the two ground states of the model, and grow likewise
logarithmically in time. Data collected at different temperatures $T$ can be
collapsed by scaling them with $T^{1.75}$, a hitherto unnoticed feature of the
E-A model, which we relate on the one hand to the geometry of configuration
space and on the other to experimental memory and rejuvenation effects. The
rate at which a cluster flips is shown to decrease exponentially with the size
of the cluster, as recently assumed in a coarse grained model of dense
colloidal dynamics. The evolving structure of clusters in real space is finally
sssociated to the decay of the thermo-remanent magnetization.
  Our analysis provides an unconventional coarse-grained description of spin
glass aging as statistically subordinated to a Poisson quaking process and
highlights record dynamics as a viable common theoretical framework for aging
in different systems.
