The Weight of Vacuum Fluctuations

Understand

We examine the gravitational properties of Lamb shift energies.

• Using available experimental data we show that these energies have a standard gravitational behavior at the level of $\sim 10^{-5}$.
• We are motivated by the point of view that Lamb shift energies may be interpreted as a consequence of vacuum fluctuations of the electromagnetic field.
• If this is the case, our result is a test of the gravitational properties of quantum fluctuations.