If majorons exist, they could explain why neutrinos have mass and even shed light on the origins of dark matter. Unlike familiar particles like electrons or photons, majorons are beyond the Standard Model, meaning they don’t fit into our current best understanding of particle physics—but their existence would solve some serious gaps in what we know.
Majorons were first proposed as part of theories that try to explain why neutrinos are so bizarre. Unlike other fundamental particles, neutrinos have an almost vanishingly small mass, which the Standard Model alone cannot explain. One possible solution is the see-saw mechanism, a theory that suggests neutrinos get their tiny mass by interacting with something much heavier. Enter majorons: hypothetical bosons that could emerge in certain extensions of the Standard Model, where neutrinos acquire their mass through interactions with a new, hidden force.
Unlike photons, which mediate electromagnetism, or gluons, which bind quarks together, majorons would be even more elusive. They would interact extremely weakly, making them almost impossible to detect directly. However, if neutrinos decay in certain ways, they might produce majorons as invisible byproducts. This has led physicists to hunt for tiny hints of their existence in high-energy experiments and neutrino observatories.
But majorons don’t just stop at neutrino physics—they’ve also been suggested as a potential component of dark matter. Since they would interact so weakly with normal matter, they could form a vast, invisible background that fills the universe without interfering with ordinary atoms.