Alternative derivation of the Feigel effect and call for its experimental verification

TL;DR

This paper offers a simplified derivation of the Feigel effect, predicts a measurable vacuum-induced flow in a fluid under strong fields, and calls for experimental verification of these quantum vacuum phenomena.

Contribution

It provides a new, simpler derivation of the Feigel effect and proposes concrete experiments to verify the predicted vacuum-induced flow and forces.

Findings

Predicted vacuum-induced Poiseuille flow of about 100 μm/s in a magnetized fluid.

Flow rate estimated at approximately 1 ml/min for the proposed setup.

Suggested experimental methods include tracking microscopy and flow rate measurements.

Abstract

A recent theory by Feigel [Phys. Rev. Lett. {\bf 92}, 020404 (2004)] predicts the finite transfer of momentum from the quantum vacuum to a fluid placed in strong perpendicular electric and magnetic fields. The momentum transfer arises because of the optically anisotropic magnetoelectric response induced in the fluid by the fields. After summarising Feigel's original assumptions and derivation (corrected of trivial mistakes), we rederive the same result by a simpler route, validating Feigel's semi-classical approach. We then derive the stress exerted by the vacuum on the fluid which, if the Feigel hypothesis is correct, should induce a Poiseuille flow in a tube with maximum speed $\approx 100\mu$m/s (2000 times larger than Feigel's original prediction). An experiment is suggested to test this prediction for an organometallic fluid in a tube passing through the bore of a high strength magnet. The predicted flow can be measured directly by tracking microscopy or indirectly by measuring the flow rate ($\approx 1$ml/min) corresponding to the Poiseuille flow. A second experiment is also proposed whereby a `vacuum radiometer' is used to test a recent prediction that the net force on a magnetoelectric slab in the vacuum should be zero.