# Feebly Interacting Particles I: Physics Motivation and Worldwide Efforts

- Institution: CERN
- Speaker: Maxim Prof. Pospelov
- Year: 2026
- Language: English
- Subjects: Physics
- Source: [CERN](https://videos.cern.ch/record/3026402)
- Licence: [CERN](https://copyright.web.cern)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

Abstract:

The existence of dark matter and neutrino masses and mixing, the prevalence of matter over antimatter in the Universe, the apparent fine-tuning of the electroweak scale, and the absence of CP violation mediated by the strong force are the big unanswered questions of modern particle physics. They often motivate studies of feebly interacting particles, or FIPs, and in this talk I will describe a new emerging research direction in particle physics that systematizes and guides the experimental searches. I give an overview of the most interesting FIP physics targets, and worldwide efforts to discover FIPs or limit their existence.

Bio:

Maxim Pospelov is a professor of physics at the School of Physics and Astronomy, University of Minnesota, and a member of William I. Fine Theoretical Physics Institute. He has over 35 years of experience in theoretical physics research. His past research focused on indirect probes of the Standard Model via flavor physics and electric dipole moments. Pospelov has been instrumental in developing the FIP/dark sector theories and suggested novel FIP signatures that were pursued in multiple experimental searches.

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## Lectures

1. [Feebly Interacting Particles I: Physics Motivation and Worldwide Efforts](https://invisiblenetwork.ai/learn/cern/3026402/d1605f38d763), 1 h 19 min (CERN's player)