相关论文: Cosmological Birefringence and the Microwave Backg…

I present a briefly summary of the current status of inflationary models versus topological defects scenarios, as the mechanisms which could have induced the initial density perturbations, which left an imprint on the cosmic microwave…

While the major contribution to the Cosmic Microwave Background (CMB) anisotropies are the sought-after primordial fluctuations produced at the surface of last scattering, other effects produce secondary fluctuations at lower redshifts.…

We detect anisotropy in the cosmic microwave background (CMB) at degree angular scales and confirm a previous detection reported by Wollack et al. (1993). The root-mean-squared amplitude of the fluctuations is $44^{+13}_{-7} \mu$K. This may…

A birefringent universe could show itself through a rotation of the plane of polarisation of the cosmic microwave background photons. This is usually investigated using polarisation $B$ modes, which is degenerate with miscalibration of the…

I develop a method for assessing the ability of an instrument, coupled with an observing strategy, to measure the angular power spectrum of the cosmic microwave background (CMB). It allows for efficient calculation of expected parameter…

Deviations from statistical isotropy can be modeled in various ways, for instance, anisotropic cosmological models (Bianchi models), compact topologies and presence of primordial magnetic field. Signature of anisotropy manifests itself in…

We consider anisotropies in the Cosmic Microwave Background (CMB) generated by spatially limited seeds; these objects could correspond to relics of high energy symmetry breaking in the early universe. It is shown how the CMB perturbation…

The cosmic microwave background (CMB) traveled the cosmos long before it reached our telescopes today. Consequently, it is one of the best probes of fundamental processes in the early Universe that we could hope to observe. The cosmological…

When coupled to electromagnetism via a Chern-Simons interaction, axion-like particles (ALP) produce a rotation of the plane of linear polarization of photons known as cosmic birefringence. Recent measurements of cosmic birefringence…

Context: Currently, detection of the primordial gravitational waves by the B-mode of Cosmic Microwave Background (CMB) is primarily limited by our knowledge of the polarized microwave foreground emissions. Thus improvements of the…

We report measurements of anisotropy in the cosmic microwave background radiation over the multipole range l ~ 200 - 3500 with the Cosmic Background Imager based on deep observations of three fields. These results confirm the drop in power…

First results of a Cosmic Microwave Background (CMB) anisotropy experiment conducted at the Observatorio del Teide (Tenerife, Spain) are presented. The instrument is a four channel (3.1, 2.1, 1.3 and 1.1 mm) $^3$He bolometer system coupled…

Polarimetry of the Cosmic Microwave Background (CMB) represents one of the possible diagnostics aimed at testing large-scale magnetism at the epoch of the photon decoupling. The propagation of electromagnetic disturbances in a magnetized…

In the near future, observations of the cosmic microwave background (CMB) anisotropies will provide accurate determinations of many fundamental cosmological parameters. In this paper, we analyse degeneracies among cosmological parameters to…

The cosmic microwave background radiation defines a preferred cosmic rest frame, and inflationary cosmological theories predict that the microwave background temperature fluctuations should be statistically isotropic in this rest frame. For…

The current suite of results from Cosmic Microwave Background anisotropy experiments is fulfilling the promise of providing extraordinary levels of discrimination between cosmological models. We calculate a binned anisotropy power spectrum,…

We perform detailed calculations of cosmic microwave background (CMB) anisotropies in a CDM-dominated open universe with primordial adiabatic density perturbations for a variety of reionization histories. We show that to a great extent, the…

Understanding the interaction of primordial gravitational waves (GWs) with the Cosmic Microwave Background (CMB) plasma is important for observational cosmology. In this article, we provide an analysis of an effect apparently overlooked as…

We describe the signatures of a circularly polarized gravitational-wave background on the timing residuals obtained with pulsar-timing arrays. Most generally, the circular polarization will depend on the gravitational-wave direction, and we…

We question the global universe isotropy by probing the alignment of local structures in the cosmic microwave background (CMB) radiation. The original method proposed relies on a steerable wavelet decomposition of the CMB signal on the…