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Maria's VEM Explained

Mechanism first, images second

What Changes

Barbour's Variety uses pairwise separations only. Maria's VEM keeps the same scale-invariant spirit but adds an explicitly orientation-sensitive three-body term.

VEM = √I  ( α Σi<j |qiqj| / rij + β Σi<j<k |qiqjqk| (Aijk · n̂) / (rij rjk rki) )
Read it in three pieces.

The pair term is radial and separation-based.
The triangle term depends on oriented area, so it is sensitive to collective rotation-like geometry.
The coefficient β tells you how strongly that rotational organization matters.

The Geometric Mechanism

For each triple (i,j,k), Maria uses the oriented area vector Aijk = (1/2)(rij × rik). Summing over all triples creates a total oriented-area vector N = Σ(rij × rik). The unit vector n̂ = N / |N| is then an axis generated by the configuration itself.

Instructional point: the system does not receive an external axis. The axis is built from the geometry of the configuration. The magnetic-like term then rewards triangles whose oriented areas align with that emergent axis.

How to Read the Figures

PanelMeaning
Top viewProjection onto the in-plane directions. If the shape is oblate, this is where the full spread remains visible.
Side viewsProjections onto planes containing the emergent axis. Flattening shows up here first.
AspectReported as the ratio of the smallest to largest principal scale. Aspect near 1 means nearly spherical. Smaller aspect means flatter, more oblate.
αWeight of the pairwise electric-like term.
βWeight of the triangle-based magnetic-like term.

Maria's Functional by Itself

These three figures keep α = 1 fixed and vary β. In the current implementation all charges are +1 and all masses are equal. The only question being tested is: does the triangle term create an emergent flattening axis?

Maria V_EM beta 0
β = 0.0: only the pair term survives. Aspect = 1.00. The configuration is close to isotropic.
Maria V_EM beta 2
β = 2.0: flattening begins. Aspect = 0.90. The side views visibly compress relative to the top view.
Maria V_EM beta 10
β = 10.0: stronger flattening. Aspect = 0.85. The magnetic-like term is now setting the global organization.
What we understand from these three figures:

Maria's triangle term does not merely perturb the pairwise solution. It creates a self-organised preferred axis and drives the minimiser away from spherical symmetry.

Our Controlled Extension

We also tested a cheaper proxy that does not reproduce Maria's full VEM term, but asks the same qualitative question: can an orientation-sensitive correction flatten the configuration into a Jupiter/Saturn-like oblate shape?

Voblate = VS (1 + λoblate Aoblate)

This proxy is not a replacement for Maria's functional. It is a controlled extension: lower cost, easier sweeps, same geometric target.

Oblate proxy lambda 0
λoblate = 0.0: baseline shape. z/xy = 1.99. Nearly spherical in three dimensions.
Oblate proxy lambda 2 equal
λoblate = 2.0, equal masses: strong flattening. z/xy = 0.39. Same qualitative effect as Maria's magnetic-like term.
Oblate proxy lambda 2 mass ratio 1:80
λoblate = 2.0, mass ratio 1:80: flattening survives unequal masses. The heavy particles retain their own visible substructure inside the oblate envelope.

What This Shows

ClaimStatus
Maria's triangle term can generate an emergent axisShown
Increasing β produces stronger oblateness in the current equal-charge testsShown
A cheaper oblate proxy reproduces the same qualitative flattening targetShown
The proxy is mathematically equivalent to Maria's full triangle termNot claimed
Charge heterogeneity changes the resulting oblate families in an interpretable wayNot yet tested here
Maria's functional yields molecule-like local motifs and global oblateness simultaneouslyOpen

Best Next Extensions

The right narrative for the site:

First show that Maria's functional is understood on its own terms.
Then show one extension that preserves the geometric question while making larger exploratory sweeps feasible.