Some Aspects of Chirality: fermion masses and chiral pforms
(1997) Abstract
 This thesis deals with different types of chiral fields.
The properties of fermion masses are investigated from different poits of view, both within the Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices.
One model is presented where the family pattern is suggested to originate from a kind of mass scaling. A Lagrangian density is defined for an entire charge sector, such that the existence of a Dirac field with a certain mass implies the existence of other Dirac fields, where the corresponding quanta have masses which are obtained from the initial mass by a... (More)  This thesis deals with different types of chiral fields.
The properties of fermion masses are investigated from different poits of view, both within the Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices.
One model is presented where the family pattern is suggested to originate from a kind of mass scaling. A Lagrangian density is defined for an entire charge sector, such that the existence of a Dirac field with a certain mass implies the existence of other Dirac fields, where the corresponding quanta have masses which are obtained from the initial mass by a discrete scale transformation. This suggests a certain type of democratic fermion mass matrices.
Also extensions of the minimal Standard Model are investigated, obtained by including righthanded neutrions in the model. The Standard Model extended by two righthanded neutrinos gives rise to a mass spectrum with two massive and three massless (at tree level) neutrinos. No assumptions such as the seesaw assumption of a large mass scale are necessary, provided the neutrino mass matrix assumes a certain form. The phenomenological consequences of this model are discussed. The neutrino mass matrix in such a scheme has what is defined as a democratic texture. The democratic family mixing matrix, with only unit entries, is found to act as a projection matrix in the sense that multiplying any 3x3 matrix with the democratic matrix is the same as multiplying an appropriate diagonal 3x3 matrix with the democratic matrix. Neutrino mass matrices with a democratic texture are studied for the cases with two and three righthanded neutrinos, respectively.
The chiral fields that we find in the Standard Model have certain similarities with selfdual fields. Among other things, both chiral and selfdual fields suffer species doubling on the lattice. Chiral pforms are selfdual fields that appear in twiceodd dimensions. Chiral pforms violet manifest covariance, in the same sense that manifest covariance is violated by noncovariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral pforms, by introducing an infinite set of gauge fields in a carefully controlled way. (Less)  Abstract (Swedish)
 Popular Abstract in Swedish
Denna avhandling handlar till stor del om elementarpartiklars massor. I motsats till många av de andra av elementarpartiklarnas egenskaper, uppvisar partiklarnas massor inget iögonfallande mönster. De antar dessutom värden som spänner över ett mycket stort område. Att förstå partikelmassorna är ett centralt tema i dagens partikelfysik.
Egenskapen kiralitet eller "hänthet" syftar till en inre egenskap hos partiklarna, som innebär att elementarpartiklarnas beteende i vissa sammanhang skiljer på vänster och höger. Självdualitet är en (i viss mening) liknande egenskap, som också undersöks i en av artiklarna.
Avhandlingen har en lång, delvis populär inledning.
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/29422
 author
 Kleppe, Astri ^{LU}
 supervisor
 opponent

 Osland, Per, Bergen University
 organization
 publishing date
 1997
 type
 Thesis
 publication status
 published
 subject
 keywords
 relativitet, kvantmekanik, klassisk mekanik, Matematisk och allmän teoretisk fysik, massive neutrinos, fermion masses, Mathematical and general theoretical physics, selfdual fields, democratic family mixing, quantum mechanics, classical mechanics, relativity, gravitation, thermodynamics, statistical physics, statistisk fysik, termodynamik, Elementary particle physics, quantum field theory, Elementarpartikelfysik, kvantfältteori, Fysicumarkivet A:1997:Kleppe
 pages
 138 pages
 publisher
 Department of Mathematical Physics, Lund University
 defense location
 May 30 1997 at 13.15, in Kårhusets Hörsal LTH
 defense date
 19970530 13:15:00
 ISBN
 9162825771
 language
 English
 LU publication?
 yes
 additional info
 The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Mathematical Physics (Faculty of Technology) (011040002)
 id
 4b7a0b898cdb421abc9185f6fcb2d441 (old id 29422)
 date added to LUP
 20160404 10:11:27
 date last changed
 20181121 20:57:19
@phdthesis{4b7a0b898cdb421abc9185f6fcb2d441, abstract = {This thesis deals with different types of chiral fields.<br/><br> <br/><br> The properties of fermion masses are investigated from different poits of view, both within the Standard Model and in extensions of the model. It is shown how mass matrix invariants are used to define the measurables of the quark mixing matrix as invariant functions of the mass matrices.<br/><br> <br/><br> One model is presented where the family pattern is suggested to originate from a kind of mass scaling. A Lagrangian density is defined for an entire charge sector, such that the existence of a Dirac field with a certain mass implies the existence of other Dirac fields, where the corresponding quanta have masses which are obtained from the initial mass by a discrete scale transformation. This suggests a certain type of democratic fermion mass matrices.<br/><br> <br/><br> Also extensions of the minimal Standard Model are investigated, obtained by including righthanded neutrions in the model. The Standard Model extended by two righthanded neutrinos gives rise to a mass spectrum with two massive and three massless (at tree level) neutrinos. No assumptions such as the seesaw assumption of a large mass scale are necessary, provided the neutrino mass matrix assumes a certain form. The phenomenological consequences of this model are discussed. The neutrino mass matrix in such a scheme has what is defined as a democratic texture. The democratic family mixing matrix, with only unit entries, is found to act as a projection matrix in the sense that multiplying any 3x3 matrix with the democratic matrix is the same as multiplying an appropriate diagonal 3x3 matrix with the democratic matrix. Neutrino mass matrices with a democratic texture are studied for the cases with two and three righthanded neutrinos, respectively.<br/><br> <br/><br> The chiral fields that we find in the Standard Model have certain similarities with selfdual fields. Among other things, both chiral and selfdual fields suffer species doubling on the lattice. Chiral pforms are selfdual fields that appear in twiceodd dimensions. Chiral pforms violet manifest covariance, in the same sense that manifest covariance is violated by noncovariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral pforms, by introducing an infinite set of gauge fields in a carefully controlled way.}, author = {Kleppe, Astri}, isbn = {9162825771}, language = {eng}, publisher = {Department of Mathematical Physics, Lund University}, school = {Lund University}, title = {Some Aspects of Chirality: fermion masses and chiral pforms}, year = {1997}, }