Elektronernes

The electrons are elementary subatomic particles with negative electric charge. They are among the fundamental constituents of matter and, together with protons and neutrons, form atoms. In atoms, electrons occupy regions around the nucleus called electron shells or orbitals, and their arrangement determines an element’s chemical properties and behavior in reactions.

Electrons belong to the lepton family in the Standard Model of particle physics. They are considered pointlike with no confirmed substructure. Key properties include a rest mass of about 9.109 × 10^-31 kilograms, a charge of −1 elementary charge, and a quantum property called spin of 1/2. Electrons obey Fermi-Dirac statistics and the Pauli exclusion principle, which governs the arrangement of electrons in atoms.

Historically, electrons were discovered by J. J. Thomson in 1897, who used cathode-ray tubes to infer the existence of a particle much lighter than atoms and carrying negative charge. Subsequent measurements established the elementary charge and mass and led to the development of quantum mechanics and atomic theory.

Electrons interact primarily through the electromagnetic force. They exchange photons as force carriers and can be bound to nuclei by electromagnetic attraction. In solids, electron movement constitutes electric current, enabling electricity, magnetism, and a wide range of technologies. Their behavior under confinement and fields underpins chemistry, spectroscopy, electronics, and many areas of research, including quantum optics and nanoscale engineering.