Comment on the paper ``Bound States in the One-dimensional Hubbard Model''

TL;DR

This paper critiques a recent preprint, clarifying that its proposed Bethe Ansatz equations are not new and reaffirming the validity of previous conclusions based on established string Bethe equations.

Contribution

It clarifies that the recent equations are identical to Takahashi's string Bethe equations and corrects misconceptions about their novelty and associated physics.

Findings

The new equations are identical to Takahashi's string Bethe equations.

Previous conclusions based on string Bethe equations remain valid.

Some physics suggested in the preprint is incorrect.

Abstract

We comment on the preprint cond-mat/9805103 by D. Braak and N. Andrei \cite{BrAn98}. We point out that the ``new'' Bethe Ansatz equations presented in \cite{BrAn98} are identical to the Bethe equations for strings introduced by M. Takahashi for the description of thermodynamics in 1972 \cite{Takahashi72}. Some physics suggested in \cite{BrAn98} is incorrect. In particular, all former conclusions made on the basis of the string Bethe equations remain valid.