Local contribution of a quantum condensate to the vacuum energy density

TL;DR

This paper investigates how coherent matter, especially superconductors described by Ginzburg-Landau theory, contributes locally to vacuum energy density, potentially affecting gravitational vacuum fluctuations similar to the Casimir effect.

Contribution

It provides a relativistic formulation of the local vacuum energy contribution of superconducting condensates based on low-energy parameters.

Findings

The sign of the local contribution can be positive or negative depending on physical conditions.

The effects may influence local gravitational vacuum fluctuations.

Potential implications for understanding vacuum energy in quantum gravity.

Abstract

We evaluate the local contribution g_[mu nu]L of coherent matter with lagrangian density L to the vacuum energy density. Focusing on the case of superconductors obeying the Ginzburg-Landau equation, we express the relativistic invariant density L in terms of low-energy quantities containing the pairs density. We discuss under which physical conditions the sign of the local contribution of the collective wave function to the vacuum energy density is positive or negative. Effects of this kind can play an important role in bringing about local changes in the amplitude of gravitational vacuum fluctuations - a phenomenon reminiscent of the Casimir effect in QED.