Comment on: Testing the speed of the spooky action at a distance in a tabletop experiment. [Sci Rep 13, 8201 (2023)]

TL;DR

This paper discusses the validity of previous critiques of long-distance quantum experiments testing superluminal communication models, affirming their robustness against such criticisms.

Contribution

It clarifies that criticisms aimed at long-distance tunnel experiments are not applicable, supporting the validity of previous experimental bounds on superluminal communication speeds.

Findings

Most criticisms do not apply to long-distance tunnel experiments

Previous experiments set high lower bounds for tachyon velocities

The paper defends the robustness of long-distance quantum tests

Abstract

In 1989, Eberhard proposed a v-causal model where quantum correlations between entangled particles are established by communications moving at a superluminal speed v_t > c in a preferred frame. In successive years, several experiments established lower bounds for the possible tachyons velocities. In a recent paper, Luigi Santamaria Amato et al. performed an interesting east-west aligned tabletop experiment under the assumption that the preferred frame is the Cosmic Microwave Background (CMB). In that paper, they criticize long-distance experiments but here we show that most of their criticisms are not applicable to long-distance tunnel experiments where the highest lower bound was obtained.