On spontaneous photon emission in collapse models

TL;DR

This paper reexamines spontaneous photon emission in collapse models, showing that certain extra terms are artifacts dependent on noise properties and vanish under realistic conditions, aligning with previous results.

Contribution

It demonstrates that the extra term in photon emission calculations is an artifact and clarifies conditions under which previous results are recovered.

Findings

The extra term is proportional to the zero frequency Fourier component of the noise.

The extra term vanishes when the electron is in a wave packet and noise is confined.

Results align with previous Golden Rule calculations under realistic assumptions.

Abstract

We reanalyze the problem of spontaneous photon emission in collapse models. We show that the extra term found by Bassi and Duerr is present for non-white (colored) noise, but its coefficient is proportional to the zero frequency Fourier component of the noise. This leads one to suspect that the extra term is an artifact. When the calculation is repeated with the final electron in a wave packet and with the noise confined to a bounded region, the extra term vanishes in the limit of continuum state normalization. The result obtained by Fu and by Adler and Ramazanoglu from application of the Golden Rule is then recovered.