Sharp Ternary Martingale Isoperimetry and $n$-adic Takagi-Type Lower Bounds

arXiv:2607.11069 2026 Regularization 1 ideas extracted · analyzed Aug 30, 2026

What the math gives to ML

The paper gives an exact sharp isoperimetric profile for ternary martingale filtrations: among sets of fixed measure, the minimum hierarchical one-variation is the Takagi-type Bellman function T_3(x), while every n-ary set pays at least order x log(1/x). The transferable asset is an explicit occupancy-dependent lower envelope for boundary variation on a rooted n-ary hierarchy. This can become a load-aware regularizer for hierarchical MoE routing or tree-structured sparse activations, replacing blind smoothness penalties with a profile calibrated to the routed mass. The main falsifiable benefit is more coherent and stable routing at equal load balance and task loss.

Ideas from this paper

Unverified 2026

Takagi-Regularized Hierarchical Routing

Represent MoE experts as leaves of a balanced ternary tree and regularize the hierarchical boundary of each expert's assignment mask. At fixed routing mass x, the ternary martingale isoperimetric theorem supplies the explicit minimum one-variation T_3(x), so the router can be penalized according to an occupancy-dependent profile rather than a uniform parent-child disagreement cost. This should favor coherent, stable routing regions while preventing small expert supports from obtaining…

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Paper: Sharp Ternary Martingale Isoperimetry and $n$-adic Takagi-Type Lower Bounds arXiv:2607.11069