Radiation transport equations in non-Riemannian space-times
arXiv:gr-qc/0505014 · doi:10.1103/PhysRevD.71.103001
Abstract
The transport equations for polarized radiation transfer in non-Riemannian, Weyl-Cartan type space-times are derived, with the effects of both torsion and non-metricity included. To obtain the basic propagation equations we use the tangent bundle approach. The equations describing the time evolution of the Stokes parameters, of the photon distribution function and of the total polarization degree can be formulated as a system of coupled first order partial differential equations. As an application of our results we consider the propagation of the cosmological gamma ray bursts in spatially homogeneous and isotropic spaces with torsion and non-metricity. For this case the exact general solution of the equation for the polarization degree is obtained, with the effects of the torsion and non-metricity included. The presence of a non-Riemannian geometrical background in which the electromagnetic fields couple to torsion and/or non-metricity affect the polarization of photon beams. Consequently, we suggest that the observed polarization of prompt cosmological gamma ray bursts and of their optical afterglows may have a propagation effect component, due to a torsion/non-metricity induced birefringence of the vacuum. A cosmological redshift and frequency dependence of the polarization degree of gamma ray bursts also follows from the model, thus providing a clear observational signature of the torsional/non-metric effects. On the other hand, observations of the polarization of the gamma ray bursts can impose strong constraints on the torsion and non-metricity and discriminate between different theoretical models.
arXiv comment12 pages, 3 figures, accepted for publication in PRD
References in corpus (29)
- The Physics of Gamma-Ray Bursts
- Metric-Affine Gauge Theory of Gravity: Field Equations, Noether Identities, World Spinors, and Breaking of Dilation Invariance
- Generation of Magnetic Fields in the Relativistic Shock of Gamma-Ray-Burst Sources
- Gamma-Ray Bursts: Progress, Problems & Prospects
- Theories of Gamma-Ray Bursts
- Polarization of the prompt gamma-ray emission from the gamma-ray burst of 6 December 2002
- Gamma-Ray Burst Afterglow: Polarization and Analytic Light Curves
- Polarization of prompt GRB emission: evidence for electromagnetically-dominated outflow
- Linear Polarization in Gamma-Ray Bursts: The Case for an Ordered Magnetic Field
- Re-Analysis of Polarization in the Gamma-ray flux of GRB 021206
- The Most Probable Cause for the High Gamma-Ray Polarization in GRB 021206
- The discovery of polarization in the afterglow of GRB 990510 with the ESO Very Large Telescope
- Gamma-Ray Burst Polarization: Limits from RHESSI Measurements
- Evolution of the polarization of the optical afterglow of the gamma-ray burst GRB 030329
- New direction for gamma-rays
- Gamma Ray Bursts from Minijets
- Optical Spectropolarimetry of the GRB 020813 Afterglow
- Compton drag as a mechanism for very high linear polarization in Gamma-Ray Bursts
- Microlensing of -Ray Burst Afterglows
- Variable polarization in the optical afterglow of GRB 021004
- Maxwell's field coupled nonminimally to quadratic torsion: Induced axion field and birefringence of the vacuum
- Gamma-Ray Bursts: Afterglows and Central Engines
- Solar constraints on new couplings between electromagnetism and gravity
- Polarization of GRB via scattering off a relativistic sheath
- Gamma-Ray Bursts: Polarization of Afterglows from Two-Component Jets
- Torsion nonminimally coupled to the electromagnetic field and birefringence
- Cosmological model with macroscopic spin fluid
- Time delay of photons of different energies in multi-dimensional cosmological models
- Is there any evidence for extra-dimensions or quantum gravity effects from the delayed MeV-GeV photons in GRB 940217?