Superradiant interactions of cosmic relics

April 28, 2026 PIRSA:26040066 Conference Cosmology

Conference/School: Cosmological Frontiers in Fundamental Physics 2026

Arvanitaki, A. (2026). Superradiant interactions of cosmic relics. Perimeter Institute. https://pirsa.org/26040066

Arvanitaki, Asimina. Superradiant interactions of cosmic relics. Perimeter Institute, Apr. 28, 2026, https://pirsa.org/26040066

@misc{ pirsa_PIRSA:26040066,
  doi = {10.48660/26040066},
  url = {https://pirsa.org/26040066},
  author = {Arvanitaki, Asimina},
  keywords = {Cosmology},
  language = {en},
  title = {Superradiant interactions of cosmic relics},
  publisher = {Perimeter Institute},
  year = {2026},
  month = {apr},
  note = {PIRSA:26040066 see, \url{https://pirsa.org}}
}

Abstract

Cosmic relics such as the cosmic neutrino background (CνB) are among the most compelling predictions of modern cosmology, yet they remain undetected because their interactions with ordinary matter are extraordinarily weak — a 10-cm detector would expect far less than one event over the age of the universe. I will describe a new approach in which macroscopic targets, such as spin ensembles familiar from NMR, prepared in easy to achieve quantum states can respond collectively to these tiny signals. In this regime, interactions are superradiantly enhanced, with rates scaling as the square of the number of particles in the target, boosting relic neutrino signals to the Hz level. I will discuss the broader implications for detecting relic neutrinos, axion and dark-photon dark matter, and explain why neutron beams incident on tabletop systems based on NMR techniques provide a natural testing ground. Finally, I will argue that these interactions appear not as conventional energy deposits but as correlated noise, pointing toward new detection strategies rooted in quantum measurement science.