Finite-dimensional approximations of push-forwards on locally analytic functionals

Isao Ishikawa

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arXiv · 2404.10769

Finite-dimensional approximations of push-forwards on locally analytic functionals

Isao Ishikawa

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Abstract

This paper develops a functional-analytic framework for approximating the push-forward induced by an analytic map from finitely many samples. Instead of working directly with the map, we study the push-forward on the space of locally analytic functionals and identify it, via the Fourier--Borel transform, with an operator on the space of entire functions of exponential type. This yields finite-dimensional approximations of the push-forward together with explicit error bounds expressed in terms of the smallest eigenvalues of certain Hankel moment matrices. Moreover, we obtain sample complexity bounds for the approximation from i.i.d.~sampled data. As a consequence, we show that linear algebraic operations on the finite-dimensional approximations can be used to reconstruct analytic vector fields from discrete trajectory data. In particular, we prove convergence of a data-driven method for recovering the vector field of an ordinary differential equation from finite-time flow map data under fairly general conditions.

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BibTeX RIS

Isao Ishikawa. 2024-04-16. Finite-dimensional approximations of push-forwards on locally analytic functionals. https://arxiv.org/abs/2404.10769

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