Second-order fermions

It has been proposed several times in the past that one can obtain an equivalent, but in many aspects simpler description of fermions by first reformulating their first-order (Dirac) Lagrangian in terms of two-component spinors, and then integrating out the spinors of one chirality (e.g.primed or do...

Full description

Bibliographic Details
Main Author: Espin, Johnny
Format: Thesis (University of Nottingham only)
Language:English
Published: 2015
Online Access:https://eprints.nottingham.ac.uk/29954/
_version_ 1848793890268643328
author Espin, Johnny
author_facet Espin, Johnny
author_sort Espin, Johnny
building Nottingham Research Data Repository
collection Online Access
description It has been proposed several times in the past that one can obtain an equivalent, but in many aspects simpler description of fermions by first reformulating their first-order (Dirac) Lagrangian in terms of two-component spinors, and then integrating out the spinors of one chirality (e.g.primed or dotted). The resulting new Lagrangian is second-order in derivatives, and contains two-component spinors of only one chirality. The new second-order formulation simplifies the fermion Feynman rules of the theory considerably, e.g. the propagator becomes a multiple of an identity matrix in the field space. The aim of this thesis is to work out the details of this formulation for theories such as Quantum Electrodynamics, and the Standard Model of elementary particles. After having developed the tools necessary to establish the second-order formalism as an equivalent approach to spinor field theories, we proceed with some important consistency checks that the new formulation is required to pass, namely the presence or absence of anomalies in their perturbative and non-perturbative description, and the unitarity of the S-Matrix derived from their Lagrangian. Another aspect which is studied is unification, where we seek novel gauge-groups that can be used to embed all of the Standard Model content: forces and fermionic representations. Finally, we will explore the possibility to unify gravity and the Standard Model when the former is seen as a diffeomorphism invariant gauge-theory.
first_indexed 2025-11-14T19:07:29Z
format Thesis (University of Nottingham only)
id nottingham-29954
institution University of Nottingham Malaysia Campus
institution_category Local University
language English
last_indexed 2025-11-14T19:07:29Z
publishDate 2015
recordtype eprints
repository_type Digital Repository
spelling nottingham-299542025-02-28T11:36:26Z https://eprints.nottingham.ac.uk/29954/ Second-order fermions Espin, Johnny It has been proposed several times in the past that one can obtain an equivalent, but in many aspects simpler description of fermions by first reformulating their first-order (Dirac) Lagrangian in terms of two-component spinors, and then integrating out the spinors of one chirality (e.g.primed or dotted). The resulting new Lagrangian is second-order in derivatives, and contains two-component spinors of only one chirality. The new second-order formulation simplifies the fermion Feynman rules of the theory considerably, e.g. the propagator becomes a multiple of an identity matrix in the field space. The aim of this thesis is to work out the details of this formulation for theories such as Quantum Electrodynamics, and the Standard Model of elementary particles. After having developed the tools necessary to establish the second-order formalism as an equivalent approach to spinor field theories, we proceed with some important consistency checks that the new formulation is required to pass, namely the presence or absence of anomalies in their perturbative and non-perturbative description, and the unitarity of the S-Matrix derived from their Lagrangian. Another aspect which is studied is unification, where we seek novel gauge-groups that can be used to embed all of the Standard Model content: forces and fermionic representations. Finally, we will explore the possibility to unify gravity and the Standard Model when the former is seen as a diffeomorphism invariant gauge-theory. 2015-12-11 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/29954/1/Thesis_JohnnyESPIN_02-09-2015_TwoSided.pdf Espin, Johnny (2015) Second-order fermions. PhD thesis, University of Nottingham.
spellingShingle Espin, Johnny
Second-order fermions
title Second-order fermions
title_full Second-order fermions
title_fullStr Second-order fermions
title_full_unstemmed Second-order fermions
title_short Second-order fermions
title_sort second-order fermions
url https://eprints.nottingham.ac.uk/29954/