Comment on 'Quantum principle of relativity'

TL;DR

This paper critiques the quantum principle of relativity (QPR) by arguing that its superluminal and subluminal branches are mathematically disconnected, rendering the QPR incomplete within the framework of fundamental physical constants.

Contribution

It provides a critical analysis of QPR, highlighting the lack of a formal connection between superluminal and subluminal branches based on Heisenberg's classification.

Findings

Superluminal and subluminal branches are mathematically separable.

No coherent formalism connects the two branches.

QPR is incomplete due to this disconnect.

Abstract

Dragan and Ekert in the paper (2020 \emph{New. J. Phys.} \textbf{22} 033038) presented 'quantum principle of relativity' (QPR) based on Galilean principle of relativity, which involves both superluminal $G_S$ and subluminal $G_s$ families of observers and argue that then they are considered on the same footing it 'implies the emergence of non-deterministic dynamics, together with complex probability amplitudes and multiple trajectories.'. Here we discuss QPR in the context of Heisenberg's classification of the fundamental physical theoretical models under the role universal constants of nature: Planck's constant $h$ and speed of light $c$. We point out that both the superluminal and subluminal branches are separable in the sense that there is no mathematical coherent formalism that connect both branches. This, in particular, implies that the QPR is incomplete.