We show the existence of a new class of astrophysical objects where the self-gravity of the dust is balanced by the force arising from shielded electric fields on the charged dust. The problem of equilibrium dust clouds is formulated in terms of an equation of hydrostatic force balance together with an equation of state. Because of the dust charge reduction at high dust density, the adiabatic index reduces from two to zero. This gives rise to a mass limit M AS for the maximum dust mass that can be supported against gravitational collapse by these fields. If the total mass M D of the dust in the interstellar cloud exceeds M AS , the dust collapses, while in the case M D < M AS , equilibrium may be achieved. The physics of the mass limit is similar to the Chandrasekhar's mass limit for compact objects, such as white dwarfs and neutron stars.

An outline of a quantum approach to multi-kink profiles as coherent states in a ferromagnetic chain is given. Relying on the continuum and harmonic approximation the influence of the out-of-plane fluctuations on the stability and dynamics of multi-kink structures in a finite chain is studied and compared with the stability and dynamics of single-kink profiles in an infinite chain. Even in the harmonic approximation, very few modes are diagonal. n e multi-kink structure does not exhibit a 'zero-frequency' Goldstone mode. This is a consequence of the out-of-ptane fluctuations.

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