  It is predicted that in force microscopy the quantum fluctuations responsible
for the Casimir force can be directly observed as temperature-independent force
fluctuations having spectral density $9\pi/(40\ln(4/e)) \hbar \delta k$, where
$\hbar$ is Planck's constant and $\delta k$ is the observed change in spring
constant as the microscope tip approaches a sample. For typical operating
parameters the predicted force noise is of order $10^{-18}$ Newton in one Hertz
of bandwidth. The Second Law is respected via the fluctuation-dissipation
theorem. For small tip-sample separations the cantilever damping is predicted
to increase as temperature is reduced, a behavior that is reminiscent of the
Kondo effect.
