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Renormalization Group Running of the Parity Operator in Lorentz-Violating Quantum Field Theory
Brett Altschul
In conventional relativistic quantum field theory, the discrete operators , , and are matrix operators with no renormalization scale dependence…
Creation of Bound Half-Fermion Pairs by Solitons
Sapan Karki, Brett Altschul
In the presence of topologically nontrivial bosonic field configurations, the fermion number operator may take on fractional eigenvalues, because of the existence of zero-energy fe…
Radiation from an Oscillating Dipole in the Presence of Photon-Sector CPT and Lorentz Violation
Joshua O'Connor, Brett Altschul
We examine one of the standard loci for studying electromagnetic wave emission -- the radiation from an oscillating electric dipole -- in a model in which the electromagnetic secto…
Perturbative Aspects of CPT-Even Lorentz-Violating Scalar Chromodynamics
B. Altschul, L. C. T. Brito, J. C. C. Felipe +3
In this work, we formulate the theory of Lorentz-violating scalar Quantum Chromodynamics with an arbitrary non-Abelian gauge group. This theory belongs to the class of models encom…
Aspects of the Equivalence Between the and Terms in Lorentz-Violating Quantum Field Theory
Sapan Karki, Brett Altschul
It is known that in Lorentz-violating effective field theory, there is a classical equivalence between certain coefficients ( and ), in spite of the fact that the operators t…
Three- and Four-Point Functions in CPT-Even Lorentz-Violating Scalar QED
B. Altschul, L. C. T. Brito, J. C. C. Felipe +3
The renormalization of quantum field theories usually assumes Lorentz and gauge symmetries, besides the general restrictions imposed by unitarity and causality. However, the set of…
Single-Particle Quantum Mechanics of the Free Klein-Gordon Equation with Lorentz Violation
Brett Altschul
In spite of its problems with interactions, the first-quantized Klein-Gordon equation is a satisfactory theory of free spinless particles. Moreover, the usual theory may be extende…
Renormalization Scheme Dependence of -Functions In Lorentz-Violating Quantum Field Theory
Sapan Karki, Brett Altschul
Effective quantum field theories that allow for the possibility of Lorentz symmetry violation can sometimes also include redundancies of description in their Lagrangians. Explicit…
Problems with Lorentz Violation Originating From a Cosmologically Varying Pseudoscalar Field
Sapan Karki, Brett Altschul
Lorentz- and CPT-violating models of electrodynamics with Chern-Simons terms are typically plagued by various sorts of instabilities. However, when the Chern-Simons term arises fro…
There is No Ambiguity in the Radiatively Induced Gravitational Chern-Simons Term
Brett Altschul
Quantum corrections to Lorentz- and CPT-violating QED in flat spacetime produce unusual radiative corrections, which can be finite but of undetermined magnitude. The corresponding…
Mode Analysis for Energetics of a Moving Charge In Lorentz- and CPT-Violating Electrodynamics
Richard DeCosta, Brett Altschul
In isotropic but Lorentz- and CPT-violating electrodynamics, it is known that a charge in unifom motion does not lose any energy to Cerenkov radiation. This presents a puzzle, sinc…
No Contact Terms for the Magnetic Field in Lorentz- and CPT-Violating Electrodynamics
Karl Schober, Brett Altschul
In a Lorentz- and CPT-violating modification of electrodynamics, the fields of a moving charge are known to have unusual singularities. This raises the question of whether the sing…
No Vacuum Cerenkov Radiation Losses in the Timelike Lorentz-Violating Chern-Simons Theory
Karl Schober, Brett Altschul
In a Lorentz- and CPT-violating modification of electrodynamics that includes a timelike Chern-Simons term, there are no energy losss through vacuum Cerenkov radiation. A charge mo…
Absence of Long-Wavelength Cerenkov Radiation With Isotropic Lorentz and CPT Violation
Brett Altschul
Modified theories of electrodynamics that include violations of Lorentz symmetry often allow for the possibility of vacuum Cerenkov radiation. This phenomenon has previously been s…
Coupling Right- and Left-Handed Photons Differently to Charged Matter
Brett Altschul
We consider a modification of electrodynamics in which right- and left-circularly polarized photons are coupled to charged sources differently. Even though photon helicity is a Lor…
Lorentz and CPT Violation in Scalar-Mediated Potentials
Brett Altschul
In Lorentz- and CPT-violating effective field theories involving scalar and spinor fields, there exist forms of Lorentz violation that modify only the scalar-spinor Yukawa interact…
Lorentz Violation and the Higgs Mechanism
Brett Altschul
We consider scalar quantum electrodynamics in the Higgs phase and in the presence of Lorentz violation. Spontaneous breaking of the gauge symmetry gives rise to Lorentz-violating g…
Renormalization of Scalar and Yukawa Field Theories with Lorentz Violation
Alejandro Ferrero, Brett Altschul
We consider a theory of scalar and spinor fields, interacting through Yukawa and phi^4 interactions, with Lorentz-violating operators included in the Lagrangian. We compute the lea…
Radiatively Induced Lorentz and Gauge Symmetry Violation in Electrodynamics with Varying alpha
Alejandro Ferrero, Brett Altschul
A time-varying fine structure constant alpha(t) could give rise to Lorentz- and CPT-violating changes to the vacuum polarization, which would affect photon propagation. Such change…
Astrophysical Bounds on the Photon Charge and Magnetic Moment
Brett Altschul
If the photon possessed an electric charge or a magnetic moment, light waves propagating through magnetic fields would acquire new quantum mechanical phases. For a charged photon,…
Finite Duration and Energy Effects in Lorentz-Violating Vacuum Cerenkov Radiation
Brett Altschul
Vacuum Cerenkov radiation is possible in certain Lorentz-violating quantum field theories, when very energetic charges move faster than the phase speed of light. In the presence of…
Cerenkov Radiation in a Lorentz-Violating and Birefringent Vacuum
Brett Altschul
We calculate the emission spectrum for vacuum Cerenkov radiation in Lorentz-violating extensions of electrodynamics. We develop an approach that works equally well if the presence…
Vacuum Cerenkov Radiation in Lorentz-Violating Theories Without CPT Violation
Brett Altschul
In theories with broken Lorentz symmetry, Cerenkov radiation may be possible even in vacuum. We analyze the Cerenkov emissions that are associated with the least constrained Lorent…
Lorentz Violation and the Yukawa Potential
B. Altschul
We analyze Lorentz violations in the bosonic sector of a Yukawa-type quantum field theory. The nonrelativistic potential may be determined to all orders in the Lorentz violation, a…