NewsPhysics

The question of how many elementary particles truly exist in the universe is more complex than it appears, with answers varying drastically from the 17 particles of the Standard Model to nearly a thousand. This disparity arises from different definitions of "elementary" and the inclusion of hypothetical particles predicted by theories beyond the Standard Model, such as supersymmetry or string theories. The search for a definitive answer is central to particle physics and the fundamental understanding of matter and forces.

The Standard Model of particle physics describes 17 fundamental particles: six quarks (up, down, charm, strange, top, bottom), six leptons (electron, muon, tau, and their respective neutrinos), four force bosons (photon, gluon, W and Z bosons), and the Higgs boson. These particles have been experimentally observed and form the basis of our current understanding of matter and fundamental interactions. However, this model does not explain phenomena such as dark matter, dark energy, or gravity, suggesting the existence of additional, yet undiscovered particles.

“This disparity arises from different definitions of "elementary" and the inclusion of hypothetical particles predicted by theories beyond the Standard Model, such as supersymmetry or string theories.”