DRUMS Mechanics of Planetary Formation
1. The Superfluid Density Gradient
Unlike classical accretion, where gravity creates a sharp boundary, the DRUMS model treats the planetary interior as a superfluid drop. The transition from the “core” to the “envelope” is governed by the superfluid density \(n_s\).
The distribution of heavier, non-superfluid elements (the “fuzz”) is influenced by the density of quantized vortices within the rotating superfluid. The density of these vortices \(n_v\) in a rotating frame is given by:
In this state, heavy elements are trapped in the cores of these vortices, preventing them from settling into a singular point. This results in a “fuzzy” or extended core where the heavy elements are distributed throughout the superfluid matrix according to the vortex density.
2. Substrate Interaction and Resonant Confinement
The magnetic substrate provides the boundary conditions for the drop. The interaction between the metallic hydrogen (conducting superfluid) and the magnetic substrate creates a Lorentz-driven confinement.
The stability of the “fuzzy” region can be modeled by the balance between the gravitational potential \(\Phi\) and the magnetic pressure gradient. For a system on a magnetic substrate, the equilibrium condition for the fluid elements is:
In the DRUMS framework, the \(\mathbf{J} \times \mathbf{B}\) term (the Lorentz force) provides an outward pressure that opposes the gravitational collapse into a sharp, solid core. This force acts as a magnetic “buoyancy” for heavy elements, keeping them suspended in a state of superfluid turbulence.
3. Surface Tension and Drop Morphology
The “fuzzy” nature of the core is further exacerbated by the surface tension of the superfluid drop on the substrate. The Young-Laplace equation modified for a magnetic substrate describes the pressure jump \(\Delta P\) across the interface:
Because the magnetic substrate is not uniform (modeled as a cubic or etched geometry), the magnetic pressure varies, causing the “drop” (the planet) to maintain an inhomogeneous internal density. This effectively “smears” the core across the nodal regions defined by the substrate’s magnetic geometry.
✦ Juno mission context
This framework accounts for the Juno data by treating the core not as a collapsed solid, but as a magnetically suspended suspension within a rotating superfluid drop. The extended, dilute “fuzzy” core emerges naturally from vortex-mediated trapping and substrate-induced magnetic confinement.