The Fermilab Holometer is a new kind of instrument designed to study the quantum character of space and time. It measures the quantum coherence of space-time locations with unprecedented precision, comparable with the smallest interval consistent with gravity and quantum mechanics, the Planck time.
Laser light passing through an arrangement of mirrors lets us measure whether space stands still, or whether it always jitters by a tiny amount, carrying all matter with it, due to quantum-geometrical fluctuations. We call this new property of space time ``holographic'' noise.
The experiment will help us understand what space and time are made of.
The experiment is also known as Fermilab E-990.