Majoranafermionen

Majorana fermions are a type of elementary particle that are their own antiparticles. This concept was first proposed by Ettore Majorana in 1937. In quantum field theory, a fermion is typically described by a wavefunction. For most fermions, like electrons, their antiparticles (positrons) are distinct entities with opposite charge and other quantum numbers. However, a Majorana fermion's wavefunction is such that it is identical to its antiparticle. This means that a Majorana fermion and its antiparticle are the same particle.

The most well-known candidate for a Majorana fermion is the neutrino. While it was initially thought that neutrinos were Dirac fermions (meaning they have distinct antiparticles), experimental evidence has increasingly pointed towards them being Majorana particles. This is because neutrinos are electrically neutral, making it difficult to distinguish them from their antiparticles based on charge. If neutrinos are indeed Majorana fermions, it would have significant implications for our understanding of particle physics, particularly in theories beyond the Standard Model that attempt to explain the small masses of neutrinos.

The existence of Majorana fermions is a topic of ongoing research in both theoretical and experimental physics. Beyond fundamental particle physics, there is also interest in realizing effective Majorana fermions in condensed matter systems. These quasiparticles can emerge in certain exotic materials under specific conditions and could potentially be used for fault-tolerant quantum computing. The search for definitive proof of their existence, particularly for neutrinos, remains a key goal in modern physics.