Searches for beyond-Riemann gravity
arXiv:2106.11293 · doi:10.1103/PhysRevD.104.044054
Abstract
Many effective field theories describing gravity cannot arise from an underlying theory based on Riemann geometry or its extensions to include torsion and nonmetricity but may instead emerge from another geometry or may have a nongeometric basis. The Lagrange density for a broad class of such theories is investigated. The action for fermions coupled to gravity is linearized about a Minkowski background and is found to include terms describing small deviations from Lorentz invariance and gravitational gauge invariance. The corresponding nonrelativistic hamiltonian is derived at second order in the fermion momentum. The implications for laboratory experiments and astrophysical observations with fermions are studied, with primary focus on anomalous spin-gravity couplings. First constraints on some coefficients are extracted from existing data obtained via measurements at different potentials, comparisons of gravitational accelerations, interferometric methods, and investigations of gravitational bound states. Some prospects for future experimental studies are discussed.
24 pages two-column REVTeX, version accepted in Physical Review D
References in corpus (39)
- Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm
- Electrodynamics with Lorentz-violating operators of arbitrary dimension
- Matter-gravity couplings and Lorentz violation
- New limit on Lorentz and CPT-violating neutron spin interactions
- Riemann-Finsler geometry and Lorentz-violating kinematics
- Constraints on Torsion from Lorentz Violation
- Preferred-Frame and CP-Violation Tests with Polarized Electrons
- Relativity tests by complementary rotating Michelson-Morley experiments
- Bipartite Riemann-Finsler geometry and Lorentz violation
- Lorentz-violating spinor electrodynamics and Penning traps
- Acoustic Rabi oscillations between gravitational quantum states and impact on symmetron dark energy
- Test of Time Dilation Using Stored Li+ Ions as Clocks at Relativistic Speed
- Parity-violating interactions of cosmic fields with atoms, molecules, and nuclei: Concepts and calculations for laboratory searches and extracting limits
- Laboratory tests of Lorentz and CPT symmetry with muons
- Limiting P-odd interactions of cosmic fields with electrons, protons and neutrons
- Classical-physics applications for Finsler space
- Gravitation and quantum interference experiments with neutrons
- Synchrotron and Inverse Compton Constraints on Lorentz Violations for Electrons
- Probing Lorentz violation with Doppler-shift experiments
- Nuclear spin-dependent interactions: Searches for WIMP, Axion and Topological Defect Dark Matter, and Tests of Fundamental Symmetries
- Constraints on long-range spin-gravity and monopole-dipole couplings of the proton
- Astrophysical Limits on Lorentz Violation for All Charged Species
- Finsler-Randers Cosmology: dynamical analysis and growth of matter perturbations
- Hermiticity of the Dirac Hamiltonian in Curved Spacetime
- Foundations of Finsler spacetimes from the Observers' Viewpoint
- Weak field equations and generalized FRW cosmology on the tangent Lorentz bundle
- Noether identities in gravity theories with nondynamical backgrounds and explicit spacetime symmetry breaking
- Limits on Neutron Lorentz Violation from the Stability of Primary Cosmic Ray Protons
- Bounds on Spin-Dependent Lorentz Violation From Inverse Compton Observations
- Muon anomalous magnetic moment in the standard model extension
- Extended Hamiltonian Formalism and Lorentz-Violating Lagrangians
- Constraining Spacetime Nonmetricity with Neutron Spin Rotation in Liquid He-4
- On the analyticity of static solutions of a field equation in Finsler gravity
- Classical Lagrangians for the nonminimal Standard-Model Extension at higher orders in Lorentz violation
- The Exact Foldy-Wouthuysen Transformation for a Dirac Theory with the complete set of CPT-Lorentz violating terms
- Gravitational Searches for Lorentz Violation with Ultracold Neutrons
- Spacetime Variation of Lorentz-Violation Coefficients at Nonrelativistic Scale
- Affine sphere spacetimes which satisfy the relativity principle
- Improved Bounds on Lorentz Symmetry Violation From High-Energy Astrophysical Sources