  Using radiation hydrodynamics simulations, we explore the evolution of
circumplanetary disks around wide-orbit proto-gas giants. At large distances
from the star (~100 AU), gravitational instability followed by disk
fragmentation can form low-mass substellar companions (massive gas giants
and/or brown dwarfs) that are likely to host large disks. We examine the
initial evolution of these subdisks and their role in regulating the growth of
their substellar companions, as well as explore consequences of their
interactions with circumstellar material. We find that subdisks that form in
the context of GIs evolve quickly from a very massive state. Long-term
accretion rates from the subdisk onto the proto-gas giant reach ~0.3 Jupiter
masses per kyr. We also find consistency with previous simulations,
demonstrating that subdisks are truncated at ~1/3 of the companion's Hill
radius and are thick, with (h/r) of great than or equal to 0.2. The thickness
of subdisks draws to question the use of thin-disk approximations for
understanding the behavior of subdisks, and the morphology of subdisks has
implications for the formation and extent of satellite systems. These subdisks
create heating events in otherwise cold regions of the circumstellar disk, and
serve as planet formation beacons that can be detected by instruments such as
ALMA.
