Towards a Theory of Quark and Lepton Masses

Towards a Theory of Quark and Lepton Masses
Author:
Publisher:
Total Pages: 10
Release: 1993
Genre:
ISBN:

Has any progress been made on understanding and predicting the 13 parameters which describe the observed masses and mixing angles of the quarks and leptons? Arguments are given in favor of pursuing schemes in which grand unified and family symmetries provide many relations among these 13 parameters. A sequence of simple assumptions leads to a supersymmetric SO(10) theory with 8 predictions: tan [beta], M{sub t}, V{sub cb}, M{sub s}, M{sub s}/M{sub d}, M{sub u}/M{sub d}, V{sub ub} and the amount of CP violation J. These predictions are presented, together with experiments which will test them.

Quarks, Leptons, and Their Constituents

Quarks, Leptons, and Their Constituents
Author: Antonino Zichichi
Publisher: Springer Science & Business Media
Total Pages: 611
Release: 2012-12-06
Genre: Technology & Engineering
ISBN: 1461308895

From 5 to 15 August 1984, a group of 79 physicists from 61 laboratories in 26 countries met in Erice for the 22nd Course of the International School of Subnuclear Physics. The countries represented were Austria, Belgium, Brazil, Bulgaria, Canada, People's Republic of China, Denmark, the Federal Republic of Germany, France, Greece, Hungary, Iran, Israel, Italy, Japan, Korea, Malaysia, Mexico, the Netherlands, Pakistan, Poland, Sweden, Switzerland, Turkey, the United Kingdom, the United States of America. The School was sponsored by the Italian Ministry of Public Education (MPI), the Italian Ministry of Scientific and Technologi cal Research (MRST), the Regional Sicilian Government (ERS), and the Weizmann Institute of Science. The programme of the School was devoted to a review of the most significant results in theoretical and experimental research work on the interactions between what we believe today are the point like constituents of the world: quarks and leptons. It should however not be forgotten that many problems are still to be understood: especially in the forefront of the correla tion between quarks and leptons. This game started in 1966 with the proposal for "leptonic quarks" and went on with "preons" and "rishons" just to quote the most famous attempts to unify these two worlds.

Unification and Supersymmetry

Unification and Supersymmetry
Author: Rabindra N. Mohapatra
Publisher: Springer Science & Business Media
Total Pages: 321
Release: 2013-06-29
Genre: Science
ISBN: 1475719280

The theoretical understanding of elementary particle interactions has under gone a revolutionary change during the past one and a half decades. The spontaneously broken gauge theories, which in the 1970s emerged as a prime candidate for the description of electro-weak (as weIl as strong) interactions, have been confirmed by the discovery of neutral weak currents as weIl as the w- and Z-bosons. We now have a field theory of electro-weak interactions at energy scales below 100 GeV-the Glashow-Weinberg-Salam theory. It is a renormalizable theory which enables us to do calculations without en countering unnecessary divergences. The burning question now is: Wh at lies ahead at the next level of unification? As we head into the era of supercolliders and ultrahigh energy machines to answer this question, many ap, pealing possi bilities exist: left-right symmetry, technicolor, compositeness, grand unifica ti on, supersymmetry, supergravity, Kaluza-Klein models, and most recently superstrings that even unify gravity along with other interactions. Experi ments will decide if any one or any combination of these is to be relevant in the description of physics at the higher energies. As an outcome of our con fidence in the possible scenerios for elementary particle physics, we have seen our understanding of the early uni verse improve significantly.

Masses And Mixings Of Quarks And Leptons

Masses And Mixings Of Quarks And Leptons
Author: Yoshio Koide
Publisher: World Scientific
Total Pages: 346
Release: 1998-03-04
Genre:
ISBN: 9814545260

It is widely accepted that quarks and leptons should be understood on the basis of the same unification scheme. The investigation of hidden rules behind observed quark and lepton mass spectra will provide a very important clue to a unified model of quarks and leptons. Now the investigation is timely because of the recent abundance of data on the CKM matrix elements and neutrino mixings. This volume offers useful information and hints on a unified understanding of quarks and leptons.

Weak Interactions of Leptons and Quarks

Weak Interactions of Leptons and Quarks
Author: Eugene D. Commins
Publisher: Cambridge University Press
Total Pages: 488
Release: 1983-07-29
Genre: Science
ISBN: 9780521273701

In recent years, the study of weak interaction and its relationship with the other fundamnetal interactions of nature has progressed rapidly. Weak interactions of leptons and quarks provides an up-to-date account of this continuing research. The Introduction discusses early models and historical developments in the understanding of the weak force. The authors then give a clear presentation of the modern theoretical basis of weak interactions, going on to discuss recent advances in the field. These include development of the eletroweak gauge theory, and the discovery of neutral currents and of a host of new particles. There is also a chapter devoted entirely to neutrino astrophysics. Its straightforward style and its emphasis on experimental results will make this book an excellent source for students (problem sets are included at the end of each chapter) and experimentalists in the field. Physicists whose speciality lies outside the study of elementary particle physics will also find it useful.

50 Years Of Quarks

50 Years Of Quarks
Author: Harald Fritzsch
Publisher: World Scientific
Total Pages: 517
Release: 2015-03-11
Genre: Science
ISBN: 9814618128

'Harald Fritzsch and Murray Gell-Mann, the two fathers of quantum chromodynamics, look back at the events that led to the discovery, and eventually acceptance, of quarks as constituent particles ... it is always worthwhile to reminisce about those times when theoretical physicists were truly eclectic, these stories are the testimony of a very active era, in which theoretical and experimental discoveries rapidly chased one another ... Of central importance now is the understanding of the composition of our universe, the dark matter and dark energy, the hierarchy of masses and forces, and a consistent quantum framework of unification of all forces of nature, including gravity. The closing contributions of the book put this venture in the context of today's high-energy physics programme, and make a connection to the most popular ideas in high-energy physics today, including supersymmetry, unification and string theory.'CERN CourierToday it is known that the atomic nuclei are composed of smaller constituents, the quarks. A quark is always bound with two other quarks, forming a baryon or with an antiquark, forming a meson. The quark model was first postulated in 1964 by Murray Gell-Mann — who coined the name “quark” from James Joyce's novel Finnegans Wake — and by George Zweig, who then worked at CERN. In the present theory of strong interactions — Quantum Chromodynamics proposed by H Fritzsch and Gell-Mann in 1972 — the forces that bind the quarks together are due to the exchange of eight gluons.On the 50th anniversary of the quark model, this invaluable volume looks back at the developments and achievements in the elementary particle physics that eventuated from that beautiful model. Written by an international team of distinguished physicists, each of whom have made major developments in the field, the volume provides an essential overview of the present state to the academics and researchers.

Theories of Fermion Masses

Theories of Fermion Masses
Author:
Publisher:
Total Pages:
Release: 1984
Genre:
ISBN:

We present grand unified theories in which the quark masses and mixing angles are calculated in terms of the lepton masses through simple group theory. The theories contain no small Yukawa couplings. A favored value of the top quark mass is 35 GeV.

Quarks, Leptons & Gauge Fields

Quarks, Leptons & Gauge Fields
Author: Kerson Huang
Publisher: World Scientific
Total Pages: 356
Release: 1992
Genre: Science
ISBN: 9789810206598

This is perhaps the most up-to-date book on Modern Elementary Particle Physics. The main content is an introduction to Yang-Mills fields, and the Standard Model of Particle Physics. A concise introduction to quarks is provided, with a discussion of the representations of SU(3).The Standard Model is presented in detail, including such topics as the Kobayashi-Maskawa matrix, chiral symmetry breaking, and the ?-vacuum. Theoretical topics of a more general nature include path integrals, topological solitons, renormalization group, effective potentials, the axial anomaly, and lattice gauge theory.This second edition, which has been expanded, incorporates the following new subjects: Wilson's renormalization scheme, and its relation to perturbative renormalization; pitfalls in quantizing gauge fields, such as the Gribov ambiguity; the lattice as a consistent regularization; Monte Carlo methods of solution; and the issues, folklores, and scenarios of quark confinement. More than a quarter of the book comprise of new materials.This book may be used as a text for a one-semester course on advanced quantum field theory, or reference book for particle physicists.

Measurement of the Top Quark Mass in the Dilepton Final State Using the Matrix Element Method

Measurement of the Top Quark Mass in the Dilepton Final State Using the Matrix Element Method
Author: Alexander Grohsjean
Publisher: Springer Science & Business Media
Total Pages: 155
Release: 2010-10-01
Genre: Science
ISBN: 364214070X

The main pacemakers of scienti?c research are curiosity, ingenuity, and a pinch of persistence. Equipped with these characteristics a young researcher will be s- cessful in pushing scienti?c discoveries. And there is still a lot to discover and to understand. In the course of understanding the origin and structure of matter it is now known that all matter is made up of six types of quarks. Each of these carry a different mass. But neither are the particular mass values understood nor is it known why elementary particles carry mass at all. One could perhaps accept some small generic mass value for every quark, but nature has decided differently. Two quarks are extremely light, three more have a somewhat typical mass value, but one quark is extremely massive. It is the top quark, the heaviest quark and even the heaviest elementary particle that we know, carrying a mass as large as the mass of three iron nuclei. Even though there exists no explanation of why different particle types carry certain masses, the internal consistency of the currently best theory—the standard model of particle physics—yields a relation between the masses of the top quark, the so-called W boson, and the yet unobserved Higgs particle. Therefore, when one assumes validity of the model, it is even possible to take precise measurements of the top quark mass to predict the mass of the Higgs (and potentially other yet unobserved) particles.