Weighing the vacuum with the Archimedes experiment

Exploring the complex connection between vacuum fluctuations and gravitational field is the goal of Archimedes experiment. Tiny changes in the weight of the vacuum contained in high-temperature superconductors can be measured using a high-precision balance. These structures can absorb or expel vacuum energy depending on their normal or superconductive status. In the measurement, the state of the sample is modulated into two states, normal and superconducting, with a reversible transition achieved by periodically varying the temperature of the thermal bath. The paper provides the current status of the experiment, highlighting the study and construction of the balance with its thermal modulation and cryogenic systems, and the investigation of high-temperature superconductor candidates.