Iterative Methods for Computing the Moore--Penrose Inverse of Split-Quaternion Matrices with Applications

arXiv:2607.29270 2026 Architecture 1 ideas extracted · analyzed Aug 31, 2026

What the math gives to ML

The transferable contribution is a representation-based pseudoinverse method with a polynomial inverse initialization, an explicit Newton–Schulz residual recursion, and a spectral acceptance test. This can replace repeated SVD pseudoinverses inside low-rank adapters, whitening layers, implicit modules, or matrix-compression blocks. The most practical adaptation is to compute a cheap polynomial start, verify contraction using an estimated residual norm, and fall back to a safe transpose-scaled start when the test fails.

Ideas from this paper

Unverified 2026

Spectrally screened polynomial pseudoinverse layer

Replace an SVD-based pseudoinverse of a learned rectangular matrix with a low-degree polynomial initialization followed by a few Newton–Schulz iterations. The polynomial approximates the inverse Gram operator, while a cheap residual test accepts it only when the iteration is contractive and otherwise selects a conservative transpose-scaled initialization.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: Iterative Methods for Computing the Moore--Penrose Inverse of Split-Quaternion Matrices with Applications arXiv:2607.29270