Scattering Cross Sections and Lorentz Violation

To date, a significant effort has been made to adddress the Lorentz violating standard model in low-energy systems, but little is known about the ramifications for high-energy cross sections. In this talk, I discuss the modified Feynman rules that result when Lorentz violation is present and give the results of an explicit calculation for electron-positron annihilation into two photons.Comment: 9 pages, 1 figure, talk presented at the second meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, August 200

Covariant Photon Quantization in the SME

The Gupta Bleuler quantization procedure is applied to the SME photon sector. A direct application of the method to the massless case fails due to an unavoidable incompleteness in the polarization states. A mass term can be included into the photon lagrangian to rescue the quantization procedure and maintain covariance.Comment: Presented at the Sixth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, June 17-21, 201

Nonrelativisitic Ideal Gasses and Lorentz Violations

We develop statistical mechanics for a nonrelativisitic ideal gas in the presence of Lorentz violating background fields. The analysis is performed using the Standard-Model Extension (SME). We derive the corresponding laws of thermodynamics and find that, to lowest order in Lorentz violation, the scalar thermodynamic variables are corrected by a rotationally invariant combination of the Lorentz terms which can be interpreted in terms of a (frame dependent) effective mass. We find that spin couplings can induce a temperature independent polarization in the gas that is not present in the conventional case.Comment: 6 pages, proceedings for CPT and Lorentz Symmetry, Bloomington, IN, 200

Deformed Instantons

In this talk, instantons are discussed in the presence of Lorentz violation. Conventional topological arguments are applied to classify the modified solutions to the Yang-Mills equations according to the topological charge. Explicit perturbations to the instantons are calculated in detail for the case of unit topological charge.Comment: 6 pages, proceedings for CPT and Lorentz Symmetry, Bloomington, IN, 200

Theoretical Overview of Lorentz and CPT Violation

In this talk, I discuss some recent theoretical progress concerning the Lorentz- and CPT-violating extension of the standard model. The results summarized include the development of an explicit connection between noncommutative field theory and the standard model extension, placement of new bounds in the photon sector, calculation of one-loop renormalization beta functions in QED, and an analysis of field redefinitions.Comment: 9 pages, to appear in the proceedings for 31st Coral Gables Conference, Ft. Lauderdale, Florid

Gupta-Bleuler Photon Quantization in the SME

Photon quantization is implemented in the standard model extension (SME) using the Gupta-Bleuler method and BRST concepts. The quantization prescription applies to both the birefringent and non-birefringent CPT-even couplings. A curious incompatibility is found between the presence of the Lorentz-violating terms and the existence of a nontrivial conjugate momentum $\Pi^0$ yielding problems with covariant quantization procedure. Introduction of a mass regulator term can avoid the vanishing of $\Pi^0$ and allows for the implementation of a covariant quantization procedure. Field-theoretic calculations involving the SME photons can then be performed using the mass regulator, similar to the conventional procedure used in electrodynamics for infrared-divergence regulation.Comment: 13 page