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We discuss the meaning of Bonnor-Ebert (BE) density profiles in
molecular cloud cores. Noting that their normalized functional form is
indistinguishable from that of dynamically collapsing solutions, we
argue that no claim of hydrostatic equilibrium can be made on the basis
of the presence of a BE density profile alone. This holds even if the
profile corresponds to a stable configuration, because a warm confining
medium, which allows for a stable equilibrium, is not necessarily
available within their parent molecular clouds. Therefore, we suggest
that the true test of equilibrium is provided by the velocity field,
not the density profile, and that a BE profile is just indicative of a
regime in which the main agent opposing self-gravity is the thermal
pressure. We furthermore investigate numerically the stage at which a
BE density profile appears for objects whose collapse is triggered by
external compressions applied to initially uniform, isothermal gas
parcels within a molecular cloud.
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