The GRANIT project: Status and Perspectives

TL;DR

The GRANIT project advances the study of quantum states of neutrons in Earth's gravity, aiming to perform spectroscopic measurements and explore potential deviations from Newtonian gravity at micrometer scales.

Contribution

It introduces a new experimental setup for inducing and measuring neutron quantum states, enabling spectroscopic analysis and searches for new physics beyond standard gravity.

Findings

Initial experiments confirmed neutron quantum states in gravity

GRANIT will perform resonant transition measurements

Potential to detect deviations from Newtonian gravity

Abstract

The GRANIT project is the follow-up of the pioneering experiments that first observed the quantum states of neutrons trapped in the earth's gravitational field at the Institute Laue Langevin (ILL). Due to the weakness of the gravitational force, these quantum states exhibit most unusual properties: peV energies and spatial extensions of order 10 $\mu$m. Whereas the first series of observations aimed at measuring the properties of the wave functions, the GRANIT experiment will induce resonant transitions between states thus accessing to spectroscopic measurements. After a brief reminder of achieved results, the principle and the status of the experiment, presently under commissioning at the ILL, will be given. In the second part, we will discuss the potential of GRANIT to search for new physics, in particular to a modified Newton law in the micrometer range.