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arXiv · 2511.12829

An Evaluation of Representation Learning Methods in Particle Physics Foundation Models

Michael Chen·Raghav Kansal·Abhijith Gandrakota·Zichun Hao·Jennifer Ngadiuba·Maria Spiropulu
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Abstract

We present a systematic evaluation of representation learning objectives for particle physics within a unified framework. Our study employs a shared transformer-based particle-cloud encoder with standardized preprocessing, matched sampling, and a consistent evaluation protocol on a jet classification dataset. We compare contrastive (supervised and self-supervised), masked particle modeling, and generative reconstruction objectives under a common training regimen. In addition, we introduce targeted supervised architectural modifications that achieve state-of-the-art performance on benchmark evaluations. This controlled comparison isolates the contributions of the learning objective, highlights their respective strengths and limitations, and provides reproducible baselines. We position this work as a reference point for the future development of foundation models in particle physics, enabling more transparent and robust progress across the community.

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Michael Chen, Raghav Kansal, Abhijith Gandrakota, Zichun Hao, Jennifer Ngadiuba, Maria Spiropulu. 2025-11-16. An Evaluation of Representation Learning Methods in Particle Physics Foundation Models. https://arxiv.org/abs/2511.12829

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