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arXiv · 2603.26793

Chiral moments make chiral measures

Emilio Pisanty·Nicola Mayer·Andrés Ordóñez·Alexander Löhr·Margarita Khokhlova
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Abstract

We develop a family of chiral measures to quantify the chirality of a distribution and assign it a handedness. Our measures are built using the tensorial moments of the distribution, which naturally encode its spatial character, not only via its angular shape consistently with existing multipolar-moment approaches, but also its radial dependence. We combine these tensorial moments into a rotationally-invariant pseudoscalar using a newly-defined cross product and triple product for arbitrary symmetric tensors. We analyze these measures for a variety of toy-model distributions, providing intuition for the geometry and guiding the choice of chiral measure optimal for a given distribution. We also apply our measures to a physically-motivated example coming from photoionization in polychromatic chiral light. Our work provides a robust, flexible, intuitive, highly geometrical, and physically-driven framework for understanding and quantifying the chirality of a wide variety of distributions, together with an open-source software package that makes this toolbox readily applicable for the analysis of numerical or experimental data.

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Emilio Pisanty, Nicola Mayer, Andrés Ordóñez, Alexander Löhr, Margarita Khokhlova. 2026-03-25. Chiral moments make chiral measures. https://arxiv.org/abs/2603.26793

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