14 March 2025
Building 1d
Europe/Berlin timezone

OmniJet-α: The first cross-task foundation model for particle physics

14 Mar 2025, 10:00
20m
O1.435 (FTX seminar room) (Building 1d)

O1.435 (FTX seminar room)

Building 1d

Speaker

Anna Hallin (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik))

Description

Foundation models are multi-dataset and multi-task machine learning methods that once pre-trained can be fine-tuned for a large variety of downstream applications. The successful development of such general-purpose models for physics data would be a major breakthrough as they could improve the achievable physics performance while at the same time drastically reduce the required amount of training time and data.
We report significant progress on this challenge on several fronts. First, a comprehensive set of evaluation methods is introduced to judge the quality of an encoding from physics data into a representation suitable for the autoregressive generation of particle jets with transformer architectures (the common backbone of foundation models). These measures motivate the choice of a higher-fidelity tokenization compared to previous works. Finally, we demonstrate transfer learning between an unsupervised problem (jet generation) and a classic supervised task (jet tagging) with our new OmniJet-α model. This is the first successful transfer between two different and actively studied classes of tasks and constitutes a major step in the building of foundation models for particle physics.

Primary authors

Anna Hallin (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik)) Gregor Kasieczka (UNI/EXP (Uni Hamburg, Institut fur Experimentalphysik)) Joschka Valentin Maria Birk (University of Hamburg)

Presentation materials