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Some Aspects of Chirality: fermion masses and chiral p-forms

Kleppe, Astri LU (1997)
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.
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 right-handed neutrions in the model. The Standard Model extended by two right-handed neutrinos gives rise to a mass spectrum with two massive and three massless (at tree level) neutrinos. No assumptions such as the see-saw 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 right-handed neutrinos, respectively.



The chiral fields that we find in the Standard Model have certain similarities with self-dual fields. Among other things, both chiral and self-dual fields suffer species doubling on the lattice. Chiral p-forms are self-dual fields that appear in twice-odd dimensions. Chiral p-forms violet manifest covariance, in the same sense that manifest covariance is violated by non-covariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral p-forms, by introducing an infinite set of gauge fields in a carefully controlled way. (Less)
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author
opponent
  • Osland, Per, Bergen University
organization
publishing date
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, self-dual 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
1997-05-30 13:15
ISBN
91-628-2577-1
language
English
LU publication?
yes
id
4b7a0b89-8cdb-421a-bc91-85f6fcb2d441 (old id 29422)
date added to LUP
2007-06-14 11:40:31
date last changed
2016-09-19 08:45:03
@phdthesis{4b7a0b89-8cdb-421a-bc91-85f6fcb2d441,
  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 right-handed neutrions in the model. The Standard Model extended by two right-handed neutrinos gives rise to a mass spectrum with two massive and three massless (at tree level) neutrinos. No assumptions such as the see-saw 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 right-handed neutrinos, respectively.<br/><br>
<br/><br>
The chiral fields that we find in the Standard Model have certain similarities with self-dual fields. Among other things, both chiral and self-dual fields suffer species doubling on the lattice. Chiral p-forms are self-dual fields that appear in twice-odd dimensions. Chiral p-forms violet manifest covariance, in the same sense that manifest covariance is violated by non-covariant gauges in electrodynamics. It is shown that a covariant action can nevertheless be formulated for chiral p-forms, by introducing an infinite set of gauge fields in a carefully controlled way.},
  author       = {Kleppe, Astri},
  isbn         = {91-628-2577-1},
  keyword      = {relativitet,kvantmekanik,klassisk mekanik,Matematisk och allmän teoretisk fysik,massive neutrinos,fermion masses,Mathematical and general theoretical physics,self-dual 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},
  language     = {eng},
  pages        = {138},
  publisher    = {Department of Mathematical Physics, Lund University},
  school       = {Lund University},
  title        = {Some Aspects of Chirality: fermion masses and chiral p-forms},
  year         = {1997},
}