  We describe a scenario for the sunspot magnetic field topology that may
account for recent observations of upflows and downflows in penumbrae.
According to our conjecture, short narrow magnetic loops fill the penumbral
volume. Flows along these field lines are responsible for both the Evershed
effect and the convective transport. This scenario seems to be qualitatively
consistent with most existing observations, including the dark cores in
penumbral filaments reported by Scharmer et al. Each bright filament with dark
core would be a system of two paired convective rolls with the dark core
tracing the lane where the plasma sinks down. The magnetic loops would have a
hot footpoint in one of the bright filament and a cold footpoint in the dark
core. The scenario also fits in most of our theoretical prejudices (siphon
flows along field lines, presence of overturning convection, drag of field
lines by downdrafts, etc). If the conjecture turns out to be correct, the mild
upward and downward velocities observed in penumbrae must increase upon
improvement of the current spatial resolution. This and other observational
tests to support or disprove the proposed scenario are put forward.
