standard model

The standard model (or standard model of particle physics) is a current well-accepted working model of particles. It considers nucleons (protons and neutrons) to be composite particles that are made up of smaller, elementary particles called quarks, along with instances of the particle-aspect of the strong force, which are a type of boson called a gluon. The model outlines a pattern among the known particles, giving order to the growing set of known particle types. It is consistent with electroweak and the strong force, but it does not explain all aspects of particle interactions, thus is considered merely a step toward a more complete model. It was developed out of the observed behavior of subatomic particles, to classify them and give some sense of how many there are. Its ideas were developed in the 1960s, gained serious acceptance in the 1970s and has been tweaked and expanded ever since, and proposed theories to cover more detail regarding particle interactions (e.g., supersymmetry) invariably build on it. The model's elementary particle types:

The phrase standard model is also used for well-established working models in other sciences. The phrase is often used without qualification in particle physics for its standard model, and in other disciplines for their own standard models, i.e., their presumably-best-accepted models, usable as working models, and whose details are well known and well documented. An example in another field is Lambda-CDM model, considered the standard model of cosmology.