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Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field
Real time evolution of classical gauge fields is relevant for a number of applications in particle physics and cosmology, ranging from the early Universe to dynamics of quark–gluon plasma. We present an explicit non-compact lattice formulation of the interaction between a shift -symmetric field and...
Autores principales: | , |
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Lenguaje: | eng |
Publicado: |
2017
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Acceso en línea: | https://dx.doi.org/10.1016/j.nuclphysb.2017.12.001 http://cds.cern.ch/record/2266116 |
_version_ | 1780954476147900416 |
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author | Figueroa, Daniel G. Shaposhnikov, Mikhail |
author_facet | Figueroa, Daniel G. Shaposhnikov, Mikhail |
author_sort | Figueroa, Daniel G. |
collection | CERN |
description | Real time evolution of classical gauge fields is relevant for a number of applications in particle physics and cosmology, ranging from the early Universe to dynamics of quark–gluon plasma. We present an explicit non-compact lattice formulation of the interaction between a shift -symmetric field and some U(1) gauge sector, a(x)FμνF˜μν , reproducing the continuum limit to order O(dxμ2) and obeying the following properties: (i) the system is gauge invariant and (ii) shift symmetry is exact on the lattice. For this end we construct a definition of the topological number density K=FμνF˜μν that admits a lattice total derivative representation K=Δμ+Kμ , reproducing to order O(dxμ2) the continuum expression K=∂μKμ∝E→⋅B→ . If we consider a homogeneous field a(x)=a(t) , the system can be mapped into an Abelian gauge theory with Hamiltonian containing a Chern–Simons term for the gauge fields. This allow us to study in an accompanying paper the real time dynamics of fermion number non-conservation (or chirality breaking) in Abelian gauge theories at finite temperature. When a(x)=a(x→,t) is inhomogeneous, the set of lattice equations of motion do not admit however a simple explicit local solution (while preserving an O(dxμ2) accuracy). We discuss an iterative scheme allowing to overcome this difficulty. |
id | cern-2266116 |
institution | Organización Europea para la Investigación Nuclear |
language | eng |
publishDate | 2017 |
record_format | invenio |
spelling | cern-22661162023-10-04T06:49:07Zdoi:10.1016/j.nuclphysb.2017.12.001http://cds.cern.ch/record/2266116engFigueroa, Daniel G.Shaposhnikov, MikhailLattice implementation of Abelian gauge theories with Chern–Simons number and an axion fieldhep-phParticle Physics - Phenomenologyastro-ph.COAstrophysics and Astronomyhep-latParticle Physics - LatticeReal time evolution of classical gauge fields is relevant for a number of applications in particle physics and cosmology, ranging from the early Universe to dynamics of quark–gluon plasma. We present an explicit non-compact lattice formulation of the interaction between a shift -symmetric field and some U(1) gauge sector, a(x)FμνF˜μν , reproducing the continuum limit to order O(dxμ2) and obeying the following properties: (i) the system is gauge invariant and (ii) shift symmetry is exact on the lattice. For this end we construct a definition of the topological number density K=FμνF˜μν that admits a lattice total derivative representation K=Δμ+Kμ , reproducing to order O(dxμ2) the continuum expression K=∂μKμ∝E→⋅B→ . If we consider a homogeneous field a(x)=a(t) , the system can be mapped into an Abelian gauge theory with Hamiltonian containing a Chern–Simons term for the gauge fields. This allow us to study in an accompanying paper the real time dynamics of fermion number non-conservation (or chirality breaking) in Abelian gauge theories at finite temperature. When a(x)=a(x→,t) is inhomogeneous, the set of lattice equations of motion do not admit however a simple explicit local solution (while preserving an O(dxμ2) accuracy). We discuss an iterative scheme allowing to overcome this difficulty.Real time evolution of classical gauge fields is relevant for a number of applications in particle physics and cosmology, ranging from the early Universe to dynamics of quark-gluon plasma. We present a lattice formulation of the interaction between a $shift$-symmetric field and some $U(1)$ gauge sector, $a(x)\tilde{F}_{\mu\nu}F^{\mu\nu}$, reproducing the continuum limit to order $\mathcal{O}(dx_\mu^2)$ and obeying the following properties: (i) the system is gauge invariant and (ii) shift symmetry is exact on the lattice. For this end we construct a definition of the {\it topological number density} $Q = \tilde{F}_{\mu\nu}F^{\mu\nu}$ that admits a lattice total derivative representation $Q = \Delta_\mu^+ K^\mu$, reproducing to order $\mathcal{O}(dx_\mu^2)$ the continuum expression $Q = \partial_\mu K^\mu \propto \vec E \cdot \vec B$. If we consider a homogeneous field $a(x) = a(t)$, the system can be mapped into an Abelian gauge theory with Hamiltonian containing a Chern-Simons term for the gauge fields. This allow us to study in an accompanying paper the real time dynamics of fermion number non-conservation (or chirality breaking) in Abelian gauge theories at finite temperature. When $a(x) = a(\vec x,t)$ is inhomogeneous, the set of lattice equations of motion do not admit however a simple explicit local solution (while preserving an $\mathcal{O}(dx_\mu^2)$ accuracy). We discuss an iterative scheme allowing to overcome this difficulty.arXiv:1705.09629CERN-TH-2017-116oai:cds.cern.ch:22661162017-05-26 |
spellingShingle | hep-ph Particle Physics - Phenomenology astro-ph.CO Astrophysics and Astronomy hep-lat Particle Physics - Lattice Figueroa, Daniel G. Shaposhnikov, Mikhail Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title | Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title_full | Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title_fullStr | Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title_full_unstemmed | Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title_short | Lattice implementation of Abelian gauge theories with Chern–Simons number and an axion field |
title_sort | lattice implementation of abelian gauge theories with chern–simons number and an axion field |
topic | hep-ph Particle Physics - Phenomenology astro-ph.CO Astrophysics and Astronomy hep-lat Particle Physics - Lattice |
url | https://dx.doi.org/10.1016/j.nuclphysb.2017.12.001 http://cds.cern.ch/record/2266116 |
work_keys_str_mv | AT figueroadanielg latticeimplementationofabeliangaugetheorieswithchernsimonsnumberandanaxionfield AT shaposhnikovmikhail latticeimplementationofabeliangaugetheorieswithchernsimonsnumberandanaxionfield |