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Lecture

CP Violation in the Early Universe

In course

PHYS-416: Particle physics II

This course aims to make students familiar and comfortable with the main concepts of particle physics, providing a clear connection between the theory and relevant experimental results, including the most recent ones from modern particle physics experiment ...

Description

This lecture discusses CP violation in the early universe, focusing on the matter/antimatter asymmetry. It covers the conditions required for generating this asymmetry, the role of CP violation in particle physics, and the CKM matrix. The GIM mechanism and weak interaction of quarks are explained, along with Feynman rules and the CPLEAR experiment. The lecture also delves into strangeness oscillations, neutral kaon decays, and CP violation in the kaon system. It concludes with a summary of the CKM matrix, CP violation in quark interactions, and the need for additional mechanisms to explain matter-antimatter asymmetry.

Instructor

Lesya Shchutska

Official source

Ontological neighbourhood

Physics

Particle physics: Standard Model

Related concepts (32)

CP violation

In particle physics, CP violation is a violation of CP-symmetry (or charge conjugation parity symmetry): the combination of C-symmetry (charge symmetry) and P-symmetry (parity symmetry). CP-symmetry states that the laws of physics should be the same if a particle is interchanged with its antiparticle (C-symmetry) while its spatial coordinates are inverted ("mirror" or P-symmetry). The discovery of CP violation in 1964 in the decays of neutral kaons resulted in the Nobel Prize in Physics in 1980 for its discoverers James Cronin and Val Fitch.

Kaon

In particle physics, a kaon (ˈkeɪ.ɒn), also called a K meson and denoted _Kaon, is any of a group of four mesons distinguished by a quantum number called strangeness. In the quark model they are understood to be bound states of a strange quark (or antiquark) and an up or down antiquark (or quark). Kaons have proved to be a copious source of information on the nature of fundamental interactions since their discovery in cosmic rays in 1947.

Neutral particle oscillation

In particle physics, neutral particle oscillation is the transmutation of a particle with zero electric charge into another neutral particle due to a change of a non-zero internal quantum number, via an interaction that does not conserve that quantum number. Neutral particle oscillations were first investigated in 1954 by Murray Gell-mann and Abraham Pais. For example, a neutron cannot transmute into an antineutron as that would violate the conservation of baryon number.

Weak interaction

In nuclear physics and particle physics, the weak interaction, which is also often called the weak force or weak nuclear force, is one of the four known fundamental interactions, with the others being electromagnetism, the strong interaction, and gravitation. It is the mechanism of interaction between subatomic particles that is responsible for the radioactive decay of atoms: The weak interaction participates in nuclear fission and nuclear fusion.

Cabibbo–Kobayashi–Maskawa matrix

In the Standard Model of particle physics, the Cabibbo–Kobayashi–Maskawa matrix, CKM matrix, quark mixing matrix, or KM matrix is a unitary matrix which contains information on the strength of the flavour-changing weak interaction. 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 violation.

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Covers gauge theories, modern particle physics, the standard model, and field content.

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Covers CP violation, the CKM matrix, quark interactions, and neutral kaons.

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Covers the constituents of matter, fundamental forces, the Standard Model, natural units, and particle interaction experiments.

Baryon Asymmetry and Particle Physics

Explores nucleosynthesis, baryon asymmetry, CP violation, and the stability of the proton in particle physics.

CKM Matrix Elements