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  • Open Access

Multiscale optimal transport for complete collider events

Tianji Cai*

Nathaniel Craig†

Katy Craig‡

Xinyuan Lin§

  • School of Physical Science and Engineering, Tongji University, Shanghai 200092, China and State Key Laboratory of Autonomous Intelligent Unmanned Systems, MOE Frontiers Science Center for Intelligent Autonomous Systems, Tongji University, Shanghai 200092, China

  • *Contact author: tianjiresearch@gmail.com
  • †Contact author: ncraig@ucsb.edu
  • ‡Contact author: kcraig@math.ucsb.edu
  • §Contact author: xil244@ucsd.edu
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Phys. Rev. D 112, 036021 – Published 29 August, 2025

DOI: https://doi.org/10.1103/7nhv-hndt

Abstract

Building upon the success of optimal transport metrics defined for single collinear jets, we develop a multiscale framework that models entire collider events as distributions on the manifold of their constituent jets, which are themselves distributions on the ground space of the calorimeter. This hierarchical structure of optimal transport effectively captures relevant physics at different scales. We demonstrate the versatility of our method in two event classification tasks, which respectively emphasize intrajet substructure and interjet spatial correlations. Our results highlight the importance of a nested structure of manifolds in the treatment of full collider events, broadening the applicability of optimal transport methods in collider analyses.

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Outline

Information

Phys. Rev. D 112, 036021– Published 29 August, 2025
  • Received 9 February 2025
  • Accepted 8 July 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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