# Underground tests of quantum mechanics. Whispers in the cosmic silence?

## TL;DR

This paper reports on underground experiments testing the Pauli Exclusion Principle for electrons and searching for radiation predicted by collapse models, aiming to improve the sensitivity of quantum mechanics tests in a low-noise environment.

## Contribution

It presents results from the VIP experiment and ongoing VIP2 measurements, enhancing the precision of PEP tests and exploring spontaneous localization models.

## Key findings

- Initial VIP results set new limits on PEP violations.
- VIP2 aims to improve sensitivity by two orders of magnitude.
- Searches for radiation consistent with spontaneous localization models.

## Abstract

By performing X-rays measurements in the "cosmic silence" of the underground laboratory of Gran Sasso, LNGS-INFN, we test a basic principle of quantum mechanics: the Pauli Exclusion Principle (PEP), for electrons. We present the achieved results of the VIP experiment and the ongoing VIP2 measurement aiming to gain two orders of magnitude improvement in testing PEP. We also use a similar experimental technique to search for radiation (X and gamma) predicted by continuous spontaneous localization models, which aim to solve the "measurement problem".