Neutrinoless double beta decay without Majorana neutrinos

TL;DR

This paper proposes that neutrinoless double beta decay can occur without Majorana neutrinos due to potential cancellations in Majorana mass contributions, challenging the assumption that such decay confirms Majorana neutrinos.

Contribution

It introduces a mechanism where neutrinoless double beta decay can be observed even if neutrinos are Dirac particles, contradicting previous beliefs.

Findings

Neutrinoless double beta decay may not imply Majorana neutrinos.

Majorana mass contributions can cancel out, allowing decay with Dirac neutrinos.

Observation of decay does not necessarily confirm neutrino Majorana nature.

Abstract

It is firmly believed that a signal of neutrinoless double beta decay can unquestionably confirm the Majorana nature of neutrinos. However we notice that a Majorana neutrino mass induced after some neutrinoless double beta decay processes can be accidentally cancelled by another Majorana neutrino mass induced before any neutrinoless double beta decay processes. This realistic cancellation can simultaneously allow an observable neutrinoless double beta decay and a vanishing Majorana neutrino mass. In consequence a future discovery of neutrinoless double beta decay cannot fully rule out the possibility of Dirac neutrinos.