It is sometimes claimed that one cannot describe charged particles in gauge theories. We identify... more It is sometimes claimed that one cannot describe charged particles in gauge theories. We identify the root of the problem and present an explicit construction of charged particles. This is shown to have good perturbative properties and, asymptotically before and after scattering, to recover particle modes. Talk held by M. Lavelle at the Sixth Workshop on Non-Perturbative Quantum Chromodynamics, Paris, June 2001. To appear in the proceedings. email: bagan@ifae.es email: rhoran@plymouth.ac.uk email: mlavelle@plymouth.ac.uk email: dmcmullan@plymouth.ac.uk email: tanimura@kues.kyoto-u.ac.jp
The main features of gammagamma-->rho+/-pi-/+ are studied in terms of a gauge-invariant (Born)... more The main features of gammagamma-->rho+/-pi-/+ are studied in terms of a gauge-invariant (Born) amplitude constructed from the phenomenological rho+/--->pi+/-gamma coupling. Large cross sections are predicted and the possibility of determining the rho+/--meson magnetic moment is considered.
Abstract: The particle Fock space of the matter fields in QED can be constructed using the free c... more Abstract: The particle Fock space of the matter fields in QED can be constructed using the free creation and annihilation operators. However, these particle operators are not, even at asymptotically large times, the modes of the matter fields that enter the QED Lagrangian. In this letter we construct the fields which do recover such particle modes at large times. We are thus able to demonstrate for the first time that, contrary to statements found in the literature, a relativistic description of charged particles in QED exists. 1
The particle Fock space of the matter fields in QED can be constructed using the free creation an... more The particle Fock space of the matter fields in QED can be constructed using the free creation and annihilation operators. However, these particle operators are not, even at asymptotically large times, the modes of the matter fields that enter the QED Lagrangian. In this letter we construct the fields which do recover such particle modes at large times. We are thus able to demonstrate for the first time that, contrary to statements found in the literature, a relativistic description of charged particles in QED exists. email: bagan@ifae.es email: mlavelle@plymouth.ac.uk email: dmcmullan@plymouth.ac.uk Introduction The conclusions of this paper, that electrons are particles, will not surprise our experimental colleagues. What may come as a surprise to them is the fact that the hitherto accepted wisdom [1–4] in the theoretical community was that there does not exist any relativistic description of the electron as a particle! The root of the problem [5] lies in the masslessness of the p...
This talk will summarise the progress we have made in our programme to both characterise and cons... more This talk will summarise the progress we have made in our programme to both characterise and construct charges in gauge theories. As an application of these ideas we will see how the dominant glue surrounding quarks, which is responsible for asymptotic freedom, emerges from a constituent description of the interquark potential.
If constituent quarks are to emerge from QCD they must have well defined colour and be energetica... more If constituent quarks are to emerge from QCD they must have well defined colour and be energetically favoured. After reviewing the general properties of charges in gauge theories, a method for constructing charges is presented and applied to the infra-red structure of the theory and to the interquark potential. Both of these applications supply a physical interpretation of the structures found in the construction of charges. We will see that constituent structures arise in QCD.
Descriptions of the ground state in unbroken gauge theories with charged particles are discussed.... more Descriptions of the ground state in unbroken gauge theories with charged particles are discussed. In particular it is shown that the on-shell Green's functions and S-matrix elements corresponding to the scattering of these variables in QED are free of soft and phase infra red divergences and that these variables may be multiplicatively renormalised.
We present the optimal measurement for discriminating among quantum states when a certain fixed r... more We present the optimal measurement for discriminating among quantum states when a certain fixed rate of inconclusive measurement results is allowed and give analytical results for the maximal success probability for special cases.
It is sometimes claimed that one cannot describe charged particles in gauge theories. We identify... more It is sometimes claimed that one cannot describe charged particles in gauge theories. We identify the root of the problem and present an explicit construction of charged particles. This is shown to have good perturbative properties and, asymptotically before and after scattering, to recover particle modes. Talk held by M. Lavelle at the Sixth Workshop on Non-Perturbative Quantum Chromodynamics, Paris, June 2001. To appear in the proceedings. email: bagan@ifae.es email: rhoran@plymouth.ac.uk email: mlavelle@plymouth.ac.uk email: dmcmullan@plymouth.ac.uk email: tanimura@kues.kyoto-u.ac.jp
The main features of gammagamma-->rho+/-pi-/+ are studied in terms of a gauge-invariant (Born)... more The main features of gammagamma-->rho+/-pi-/+ are studied in terms of a gauge-invariant (Born) amplitude constructed from the phenomenological rho+/--->pi+/-gamma coupling. Large cross sections are predicted and the possibility of determining the rho+/--meson magnetic moment is considered.
Abstract: The particle Fock space of the matter fields in QED can be constructed using the free c... more Abstract: The particle Fock space of the matter fields in QED can be constructed using the free creation and annihilation operators. However, these particle operators are not, even at asymptotically large times, the modes of the matter fields that enter the QED Lagrangian. In this letter we construct the fields which do recover such particle modes at large times. We are thus able to demonstrate for the first time that, contrary to statements found in the literature, a relativistic description of charged particles in QED exists. 1
The particle Fock space of the matter fields in QED can be constructed using the free creation an... more The particle Fock space of the matter fields in QED can be constructed using the free creation and annihilation operators. However, these particle operators are not, even at asymptotically large times, the modes of the matter fields that enter the QED Lagrangian. In this letter we construct the fields which do recover such particle modes at large times. We are thus able to demonstrate for the first time that, contrary to statements found in the literature, a relativistic description of charged particles in QED exists. email: bagan@ifae.es email: mlavelle@plymouth.ac.uk email: dmcmullan@plymouth.ac.uk Introduction The conclusions of this paper, that electrons are particles, will not surprise our experimental colleagues. What may come as a surprise to them is the fact that the hitherto accepted wisdom [1–4] in the theoretical community was that there does not exist any relativistic description of the electron as a particle! The root of the problem [5] lies in the masslessness of the p...
This talk will summarise the progress we have made in our programme to both characterise and cons... more This talk will summarise the progress we have made in our programme to both characterise and construct charges in gauge theories. As an application of these ideas we will see how the dominant glue surrounding quarks, which is responsible for asymptotic freedom, emerges from a constituent description of the interquark potential.
If constituent quarks are to emerge from QCD they must have well defined colour and be energetica... more If constituent quarks are to emerge from QCD they must have well defined colour and be energetically favoured. After reviewing the general properties of charges in gauge theories, a method for constructing charges is presented and applied to the infra-red structure of the theory and to the interquark potential. Both of these applications supply a physical interpretation of the structures found in the construction of charges. We will see that constituent structures arise in QCD.
Descriptions of the ground state in unbroken gauge theories with charged particles are discussed.... more Descriptions of the ground state in unbroken gauge theories with charged particles are discussed. In particular it is shown that the on-shell Green's functions and S-matrix elements corresponding to the scattering of these variables in QED are free of soft and phase infra red divergences and that these variables may be multiplicatively renormalised.
We present the optimal measurement for discriminating among quantum states when a certain fixed r... more We present the optimal measurement for discriminating among quantum states when a certain fixed rate of inconclusive measurement results is allowed and give analytical results for the maximal success probability for special cases.
Uploads
Papers by Emili Bagan