Why Screening Effects Do Not Influence the Casimir Force

TL;DR

This paper argues that including screening effects and diffusion currents in Lifshitz theory violates thermodynamics and contradicts experimental data, showing these effects do not influence the Casimir force.

Contribution

The paper demonstrates that modified reflection coefficients accounting for screening effects violate thermodynamics and are inconsistent with experimental results, challenging recent theoretical proposals.

Findings

Screening effects do not influence the Casimir force.

Modified reflection coefficients violate the third law of thermodynamics.

Experimental data contradict the inclusion of screening effects.

Abstract

The Lifshitz theory of dispersion forces leads to thermodynamic and experimental inconsistencies when the role of drifting charge carriers is included in the model of the dielectric response. Recently modified reflection coefficients were suggested that take into account screening effects and diffusion currents. We demonstrate that this theoretical approach leads to a violation of the third law of thermodynamics (Nernst's heat theorem) for a wide class of materials and is excluded by the data from two recent experiments. The physical reason for its failure is explained by the violation of thermal equilibrium, which is the fundamental applicability condition of the Lifshitz theory, in the presence of drift and diffusion currents.