The Third IUCSS Workshop on Theoretical Aspects of the Standard-Model Extension will be hosted by the Physics Department, Indiana University in Bloomington, Indiana, U.S.A. on January 27-28, 2024.

The Workshop focus will primarily be on theoretical and phenomenological aspects of violations of spacetime symmetries in the context of the comprehensive effective field theory based on General Relativity and the Standard Model, the Standard-Model Extension (SME). The format will consist of short talks summarizing recent developments and prospects for future advances. Participation will be both in person and online. Priority in scheduling presentations will be given to in-person talks.

Topics in the SME to be discussed at the Workshop are expected to include:

• realistic EFT for Lorentz and CPT violation in particle physics and gravity
• classification and properties of operators with arbitrary mass dimensions
• coordinate and frame choices, field redefinitions
• explicit and spontaneous breaking of Lorentz and diffeomorphism symmetry
• Nambu-Goldstone, gauge, and auxiliary modes, constrained systems
• stability, causality, and unitarity
• quantum corrections, renormalization
• geometry and Lorentz violation, no-go results
• Riemann-Finsler and Lorentz-Finsler spaces
• anisotropy, dispersion, and birefringence of matter, gauge, and gravity fields
• antimatter properties and couplings
• flavor-changing Lorentz violation
• Weyl and Dirac semimetals
• QCD and hadronic physics, parton model, chiral perturbation theory
• post-Newtonian gravity, equivalence principle
• astrophysical effects on photons, neutrinos, gravitational waves, cosmic rays
• neutron stars, black holes, cosmology
• experimental and observational searches for violations

There is no registration fee for this Workshop, but online registration before Tuesday January 23 is required. The total attendance is likely to be capped, so early registration is advised to avoid disappointment.