Comment on "A Lagrangian for DSR Particle and the Role of Noncommutativity"

TL;DR

This paper critiques a previous work on DSR particles, clarifying that its proposed Lagrangian is equivalent to a standard relativistic particle and that noncommutative structures do not affect Lorentz covariance.

Contribution

It provides a critical analysis clarifying misconceptions about the Lagrangian and the role of noncommutativity in Ghosh's DSR formalism.

Findings

The Lagrangian in Ghosh's paper is equivalent to the standard relativistic particle.

Noncommutative structures are not relevant to Lorentz covariance issues.

Ghosh's model does not describe the Magueijo-Slomin DSR model.

Abstract

In this work, we comment on two special points in the paper by S. Ghosh [Phys. Rev. D 74, 084019 (2006)]. First of all, the Lagrangian presented by the author does not describe the Magueijo- Smolin model of Doubly Special Relativity since it is equivalent to the Lagrangian of the standard free relativistic particle. We also show that the introduction of noncommutative structures is not relevant to the problem of Lorentz covariance in Ghosh formalism.