Comments on "Translation-invariant bipolarons and the problem of high-temperature superconductivity"

TL;DR

This paper critically examines recent claims about bipolaron ground state energies in high-temperature superconductivity, clarifying that previous results lack a proven variational upper bound, thus questioning their validity.

Contribution

It provides a critical analysis of prior bipolaron energy calculations, highlighting the absence of a proven variational upper bound in those results.

Findings

Previous bipolaron energy results are not proven to be variational upper bounds.

The critique challenges the validity of recent high-temperature superconductivity models.

Clarifies the limitations of the Gross-Tulub approximation in this context.

Abstract

We comment on the recent results of Refs. [1, 2] on the bipolaron problem derived using an approximation of Gross - Tulub. It is proved that, contrary to the claim made in Refs. [1, 2], the bipolaron ground state energy calculated there in the strong-coupling approximation has not been shown to constitute a variational upper bound.