Dirac fermion facts for kids

A Dirac fermion is a special kind of particle that is different from its antiparticle. Think of it like a person and their reflection in a mirror – they are similar but not exactly the same. Most particles we know, like electrons and quarks, are Dirac fermions.

Scientists use the Standard Model of physics to understand these tiny particles. In this model, almost every particle has its own antiparticle. Dirac fermions are named after a famous scientist named Paul Dirac, who developed an important equation called the Dirac equation to describe them.

Particles and Antiparticles

Every particle has an antiparticle. An antiparticle has the same mass as its particle partner but opposite electric charge and other properties. For example, the antiparticle of an electron is called a positron. An electron has a negative charge, while a positron has a positive charge. Since an electron is different from a positron, the electron is a Dirac fermion.

When a particle meets its antiparticle, they can destroy each other in a burst of energy. This process is called annihilation.

Dirac vs. Majorana Fermions

There is another type of particle called a Majorana fermion. Unlike a Dirac fermion, a Majorana fermion is its own antiparticle. This means it's like looking in a mirror and seeing yourself exactly, with no differences.

Scientists are still trying to figure out if any particles are truly Majorana fermions. Neutrinos, which are tiny particles with no electric charge, are candidates for being Majorana fermions. If neutrinos turn out to be Majorana fermions, it would be a big discovery in particle physics!