Optimal mean width and metric entropy estimates for convex bodies
arXiv:2607.29522
2026
Geometry
1 ideas extracted · analyzed Aug 31, 2026
What the math gives to ML
The paper establishes an affine-normalization principle: every convex body admits a linear image whose Euclidean covering entropy is controlled, up to universal constants, by that of the crosspolytope, while the optimal mean-width-to-volume-radius ratio is at most O(sqrt(log(en))). The transferable asset is the use of determinant-constrained linear transformations to remove harmful anisotropy without allowing representation collapse, together with mean width and covering entropy as geometric compactness criteria. A practical neural-network adaptation is to insert a learned determinant-one affine preconditioner on hidden representations and optimize a sampled mean-width-to-volume proxy, testing whether it produces more compressible and better-conditioned activations than LayerNorm or whitening.
Ideas from this paper
Unverified
2026
Replace or augment LayerNorm on a hidden representation by a learned volume-preserving linear map that minimizes the representation cloud's spherical mean width relative to a volume proxy. The determinant constraint prevents trivial shrinking, so the module targets anisotropy and elongated activation clouds; the expected benefit is a tighter geometry that is easier to quantize or cover with a small codebook.
Useful5/10
Difficulty6/10
Novelty7/10