相关论文: Generation of Circular Polarization of the Cosmic …
We summarize the physical mechanism by which the Cosmic Microwave Background acquires a small degree of polarization. We discuss the imprint left by gravitational waves and the use of polarization as a test of the inflationary paradigm. We…
When a cosmic microwave background (CMB) photon travels from the surface of last scatter through spacetime metric perturbations, the polarization vector may rotate about its direction of propagation. This gravitational rotation is distinct…
Circular polarization of the cosmic microwave background (CMB) can be induced by Faraday conversion of the primordial linearly polarized radiation as it propagates through a birefringent medium. Recent work has shown that the dominant…
A dark energy scalar (or a function of the Ricci scalar) coupled with the derivative to the matter fields will violate the $CPT$ symmetry during the expansion of the Universe. This type of cosmological $CPT$ violation helps to generate the…
In this work I study the polarization of the Cosmic Microwave Background (CMB) induced by a cosmological background of gravitational waves (here GWs) and I discuss the enhancement effect of a possible late and fast reionization of the…
The contribution of one loop milli-charged fermion vacuum polarization in cosmic magnetic field to the cosmic microwave background (CMB) polarization is considered. Exact and perturbative solution of the density matrix equations of motion…
Non-gaussianity and B-mode polarization are particularly interesting features of the cosmic microwave background, as -- at least in the standard model of cosmology -- their only sources to first order in cosmological perturbation theory are…
We introduce a new multipole formalism for polarized radiative transfer in general spacetime geometries. The polarization tensor is expanded in terms of coordinate-independent, projected symmetric trace-free (PSTF) tensor-valued multipoles.…
Mechanisms have been proposed that might rotate the linear polarization of the cosmic microwave background (CMB) as it propagates from the surface of last scatter. In the simplest scenario, the rotation will be uniform across the sky, but…
We examine the polarization signal of the cosmic microwave background radiation associated with distant clusters. The polarization is induced by the Thomson scattering of microwave photons with ionized gas of clusters and contains…
The polarization of the cosmic microwave background radiation will have a distribution of singularities and anti-singularities, points where the polarization vanishes for topological reasons. The statistics of polarization singularities…
When the last electron-photon scattering takes place in a magnetized environment, the degree of circular polarization of the outgoing radiation depends upon the magnetic field strength. After deriving the scattering matrix of the process,…
Recent cosmic microwave background data in temperature and polarization have reached high precision in estimating all the parameters that describe the current so-called standard cosmological model. Recent results about the integrated…
Certain modified gravity theories predict the existence of an additional, non-conformally coupled scalar field. A disformal coupling of the field to the Cosmic Microwave Background (CMB) is shown to affect the evolution of the energy…
The polarization dependence of the low field microwave photoconductivity and absorption of a two-dimensional electron system has been investigated in a quasi-optical setup in which linear and any circular polarization can be produced…
The coupling of a scalar field to electromagnetic field via the Chern-Simons term will rotate the polarization directions of the cosmic microwave background radiation. The rotation angle which relies on the distribution of the scalar field…
Polarization of the cosmic microwave background (CMB) brings out information not only on the early universe but also on the late-time large-scale structure via weak gravitational lensing. Here, we show that circular polarization is induced…
Hints of cosmic microwave background polarization rotation ($\Delta\vartheta \sim 10^{-3}$ rad) are commonly attributed to late-time dynamics of ultralight axions. We show that such ultralight degrees of freedom are not required.…
Photon-photon interactions, as described by the standard Heisenberg-Euler interaction, can transform plane polarization of the CMB into circular polarization, in the period right after last scattering. We estimate the standard deviation of…
We quantify the level of polarization of the atmosphere due to Zeeman splitting of oxygen in the Earth's magnetic field and compare it to the level of polarization expected from the polarization of the cosmic microwave background radiation.…