## Standard Model

In particle physics, the baryon number is an approximate conserved quantum number. The baryon number of a system is defined as the number of quarks divided by three minus the number of antiquarks in the system divided by three. ...more on Wikipedia about "Baryon number"

A chiral anomaly is the anomalous nonconservation of a chiral current. In some theories of fermions with a chiral symmetry the quantization may lead to the breaking of this (global) chiral symmetry. In that case, the charge associated with the chiral symmetry is not conserved. ...more on Wikipedia about "Chiral anomaly"

In the standard model of particle physics the Cabibbo Kobayashi Maskawa matrix (CKM matrix, sometimes earlier called KM matrix) is a unitary matrix which contains information on the strength of flavour changing weak decays. Technically, it specifies the mismatch of quantum states of quarks when they propagate freely and when they take part in the weak interactions. It is important in the understanding of CP violations. A precise mathematical definition of this matrix is given in the article on the formulation of the standard model. This matrix was introduced for three generations of quarks by Makoto Kobayashi and Toshihide Maskawa, adding one generation to the matrix previously introduced by Nicola Cabibbo. ...more on Wikipedia about "CKM matrix"

In physics, the Ellis-Karliner angle is kinematical angle between the highest energy jets in a three jet event. The angle is not measured in the lab frame, but in a frame boosted along the energy of the highest energy jet so that the second and third jets are back-to-back. By measuring the distribution of the Ellis-Karliner angle at linear colliders, the gluon was determined to have spin one as opposed to spin zero or spin two. ...more on Wikipedia about "Ellis-Karliner angle"

Flavour (or flavor) is a quantum number of elementary particles related to their weak interactions. In the electroweak theory this symmetry is gauged, and flavour changing processes exist. In quantum chromodynamics, on the other hand, flavour is a global symmetry. ...more on Wikipedia about "Flavour (particle physics)"

The Higgs mechanism or Anderson-Higgs mechanism, originally proposed by the British physicist Peter Higgs based on a suggestion by Philip Anderson, is the mechanism that gives mass to all elementary particles in particle physics. It makes the W boson different from the photon, for example. It can be understood as an elementary case of tachyon condensation where the role of the tachyon is played by a scalar field called the Higgs field. The massive quantum excitation of the Higgs field is also called the Higgs boson. ...more on Wikipedia about "Higgs mechanism"

In particle physics, the hypercharge (represented by Y) is the sum of the baryon number B and the flavor charges: strangeness S, charm C, bottomness $\tilde B$ and topness T, although the last one can be omitted given the extremely short life of the top quark (it decays to other quarks before strong-interacting with other quarks). ...more on Wikipedia about "Hypercharge"

Fast shortopedia

In the Standard Model of particle physics the Maki-Nakagawa-Sakata matrix (MNS matrix or sometimes PMNS matrix to include Pontecorvo) is a unitary matrix which contains information on the mismatch between mass and weak flavour quantum states of neutrinos. It is the equivalent of the CKM matrix in the quark sector. ...more on Wikipedia about "Maki-Nakagawa-Sakata matrix"

In particle physics neutral particle oscillation is the transmutation of a neutral particle with nonzero internal quantum numbers into its antiparticle. These oscillations and the associated mixing of particles gives insight into the realization of discrete parts of the Poincare group, ie, parity (P), charge conjugation (C) and time reversal invariance (T). ...more on Wikipedia about "Neutral particle oscillations"

Neutrino oscillation is a quantum mechanical phenomenon whereby a neutrino created with a specific lepton flavor (electron, muon, or tau) can later be measured to have a different flavor. More specifically, the probability of measuring a particular flavor for a neutrino varies periodically as it propagates. Neutrino oscillation is of theoretical and experimental interest, as observation of the phenomenon implies nonzero neutrino mass. ...more on Wikipedia about "Neutrino oscillation"

Spontaneous symmetry breaking in physics takes place when a system that is symmetric with respect to some symmetry group goes into a vacuum state that is not symmetric. At this point the system no longer appears to behave in a symmetric manner. It is a phenomenon that naturally occurs in many situations. The symmetry group can be discrete, such as the space group of a crystal, or continuous (i.e. a Lie group), such as the rotational symmetry of space. ...more on Wikipedia about "Spontaneous symmetry breaking"

The Standard Model of particle physics is a theory which describes the strong, weak, and electromagnetic fundamental forces, as well as the fundamental particles that make up all matter. Developed between 1970 and 1973, it is a quantum field theory, and consistent with both quantum mechanics and special relativity. To date, almost all experimental tests of the three forces described by the Standard Model have agreed with its predictions. However, the Standard Model is not a complete theory of fundamental interactions, primarily because it does not describe the gravitational force. ...more on Wikipedia about "Standard Model"

(Standard model (basic details)) where we have introduced the Weinberg angle, θW. In terms of this, one can write ...more on Wikipedia about "Standard model (basic details)"

Weak hypercharge is twice the difference between the electrical charge and the weak isospin. It is the generator of the center of the electroweak gauge group. ...more on Wikipedia about "Weak hypercharge"

In particle physics, Yukawa interaction, named after Hideki Yukawa, is an interaction between a scalar field $\phi$ and a Dirac field $\Psi$ of the type ...more on Wikipedia about "Yukawa interaction"