Related papers: Penning-Trap Searches for Lorentz and CPT Violatio…
A general formalism is presented for violations of Lorentz and CPT symmetry in the neutrino sector. The effective hamiltonian for neutrino propagation in the presence of Lorentz and CPT violation is derived, and its properties are studied.…
A short review is given of some theoretical approaches to CPT violation. A potentially realistic possibility is that small apparent breaking of CPT and Lorentz symmetry could arise at the level of the standard model from spontaneous…
We investigate Lorentz- and CPT-violating effects in neutron and storage-ring electric dipole moment (EDM) experiments within the framework of the Standard-Model Extension (SME). For neutron EDM experiments, perturbation theory is applied…
This work tabulates measured and derived values of coefficients for Lorentz and CPT violation in the Standard-Model Extension. Summary tables are extracted listing maximal attained sensitivities in the matter, photon, neutrino, and gravity…
This talk at the CPT'19 meeting outlines a few recent developments in Lorentz and CPT violation, with particular attention to results obtained by researchers at the Indiana University Center for Spacetime Symmetries.
The ongoing experimental efforts in the high energy and high precision communities keep providing evidence for CPT, a fundamental symmetry holding in any local Lorentz invariant theory. We suggest possible interconnections between different…
Low-energy remnant fundamental symmetry violations may be present in nature at levels attainable in upcoming experiments. These effects may arise through spontaneous symmetry breaking in a more complete Lorentz covariant theory underlying…
A framework is presented for the factorization of high-energy hadronic processes in the presence of Lorentz and CPT violation. The comprehensive effective field theory describing Lorentz and CPT violation, the Standard-Model Extension, is…
Spontaneous CPT breaking arising in string theory has been suggested as a possible observable experimental signature in neutral-meson systems. We provide a theoretical framework for the treatment of low-energy effects of spontaneous CPT…
This talk summarizes some recent experimental constraints on Lorentz and CPT violation.
A model for the Lorentz- and CPT-violating frequency shift for the antihydrogen $1S$-$2P$ transition in the presence of an external magnetic field is derived. Using the recent measurement of the $1S$-$2P$ transition frequency in…
This talk discusses theoretical aspects of tests of CPT and Lorentz Symmetry that will in principle be possible with trapped antihydrogen. The framework is the standard-model extension, which admits minuscule violations of CPT and Lorentz…
A theoretical framework extending QED in the context of the standard model is used to analyze a variety of Lorentz and CPT tests in atomic systems. Experimental signatures of possible Lorentz and CPT violation in these systems are…
This talk offers some comments and perspectives on Lorentz and CPT violation.
Tiny violations of the Lorentz symmetry of relativity and the associated discrete CPT symmetry could emerge in a consistent theory of quantum gravity such as string theory. Recent evidence for linear polarization in gamma-ray bursts…
I review first some theoretical motivations for violation of Lorentz and/or CPT Invariance. Although the latter symmetries may be violated in a quantum gravity setting, nevertheless there are situations in which these violations are due to…
The gravitational couplings of matter are studied in the presence of Lorentz and CPT violation. At leading order in the coefficients for Lorentz violation, the relativistic quantum hamiltonian is derived from the gravitationally coupled…
Various approaches to physics beyond the Standard Model can lead to small violations of CPT invariance. Since CPT symmetry can be measured with ultrahigh precision, CPT tests offer an interesting phenomenological avenue to search for…
Space-based experiments offer sensitivity to numerous unmeasured effects involving Lorentz and CPT violation. We provide a classification of clock sensitivities and present explicit expressions for time variations arising in such…
Atomic clock comparisons provide some of the most precise tests of Lorentz and CPT symmetries in the laboratory. With data from multiple such experiments using different nuclei, it is possible to constrain new regions of the parameter space…