Structural levels and systemic organization of matter

The structure and behavior of elementary particles is studied by elementary particle physics.

All elementary particles obey the principle of identity (all elementary particles of the same kind in the Universe are completely identical in all their properties) and the principle of particle-wave dualism (each elementary particle corresponds to a de Broglie wave).

All elementary particles have the property of interconvertibility, which is a consequence of their interactions: strong, electromagnetic, weak, gravitational. Interactions of particles cause transformations of particles and their aggregates into other particles and their aggregates, if such transformations are not prohibited by the laws of conservation of energy, momentum, angular momentum, electric charge, baryon charge, etc.

The main characteristics of elementary particles are: lifetime, mass, spin, electric charge, magnetic moment, baryon charge, lepton charge, strangeness, charm, charm, truth, isotopic spin, parity, charge parity, G-parity, CP-parity, T-parity, R-parity, P-parity.

All elementary particles are divided into two classes:

Stable elementary particles are particles that have an infinitely long lifetime in the free state (proton, electron, neutrino, photon, graviton and their antiparticles).

Unstable elementary particles are particles that decay into other particles in a free state in a finite time (all other particles).

All elementary particles are divided into two classes:

Massless particles are particles with zero mass (photon, gluon).

Particles with nonzero mass (all other particles).

All elementary particles are divided into two classes:

bosons are particles with whole spin (for example, photon, gluon, mesons, Higgs boson);

fermions are particles with half-integer spin (for example, electron, proton, neutron, neutrino).

Elementary particles are divided into the following groups:

Composite particles

Hadrons are particles involved in all kinds of fundamental interactions. They consist of quarks and are subdivided, in turn, into: