English
Related papers

Related papers: The Cosmic Microwave Background Bipolar Power Spec…

200 papers

The statistical expectation values of the temperature fluctuations of the Cosmic Microwave Background (CMB) are assumed to be preserved under rotations of the sky. We investigate the Statistical Isotropy (SI) of the CMB anisotropy maps…

Astrophysics · Physics 2009-11-10 Amir Hajian , Tarun Souradeep , Neil Cornish

The statistical expectation values of the temperature fluctuations and polarization of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We investigate the statistical isotropy (SI) of the CMB maps…

Astrophysics · Physics 2009-11-11 Tarun Souradeep , Amir Hajian , Soumen Basak

The statistical expectation values of the temperature fluctuations of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We investigate the statistical isotropy of the CMB anisotropy maps recently…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Amir Hajian

The exquisitely measured maps of fluctuations in the Cosmic Microwave Background (CMB) present the possibility to test the principle of Statistical Isotropy (SI) of the Universe through systematic observable measures for non-Statistical…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-12 Dipanshu , Tarun Souradeep , Shriya Hirve

In this work, we present a follow-up to our previous work where the concept of minimal Bipolar spherical harmonics (mBipoSH) functions was introduced as a natural basis for studying angular correlations in the non-statistical isotropic…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-19 Dipanshu , Akashdeep Karan , Tarun Souradeep

We formulate statistical isotropy of CMB anisotropy maps in its most general form. We also present a fast and orientation independent statistical method to determine deviations from statistical isotropy in CMB polarization maps. Importance…

Astrophysics · Physics 2009-11-11 Soumen Basak , Amir Hajian , Tarun Souradeep

Gaussianity of temperature fluctuations in the Cosmic Microwave Background(CMB) implies that the statistical properties of the temperature field can be completely characterized by its two point correlation function. The two point…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-25 Nidhi Joshi , Aditya Rotti , Tarun Souradeep

Recent measurements of the temperature field of Cosmic Microwave Background (CMB) provide tantalising evidence for violation of Statistical Isotropy (SI) that constitutes a fundamental tenet of contemporary cosmology. CMB space based…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Suvodip Mukherjee , Tarun Souradeep

Recent high precision cosmological observations have revealed several anomalies in the Cosmic Microwave Background (CMB), indicating possible violations of statistical isotropy (nSI). Typically, nSI in the CMB sky is studied in the harmonic…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Vaishali R , Dipayan Mukherjee , Tarun Souradeep

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

Astrophysics · Physics 2008-11-26 Tarun Souradeep , Amir Hajian

Statistical isotropy (SI) of Cosmic Microwave Background (CMB) fluctuations is a key observational test to validate the cosmological principle underlying the standard model of cosmology. While a detection of SI violation would have immense…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-29 Santanu Das , Sanjit Mitra , Aditya Rotti , Nidhi Pant , Tarun Souradeep

Statistical isotropy (SI) is one of the fundamental assumptions made in cosmological model building. This assumption is now being rigorously tested using the almost full sky measurements of the CMB anisotropies. A major hurdle in any such…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-04 Pavan K. Aluri , Nidhi Pant , Aditya Rotti , Tarun Souradeep

Mild, unavoidable deviations from circular-symmetry of instrumental beams along with scan strategy can give rise to measurable Statistical Isotropy (SI) violation in Cosmic Microwave Background (CMB) experiments. If not accounted properly,…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-06 Nidhi Pant , Santanu Das , Aditya Rotti , Sanjit Mitra , Tarun Souradeep

Although theoretically expected to be Statistically Isotropic (SI), the observed Cosmic Microwave Background (CMB) temperature \& polarization field would exhibit SI violation due to various inevitable effects like weak lensing, Doppler…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-27 Suvodip Mukherjee , Tarun Souradeep

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

Astrophysics · Physics 2007-05-23 Amir Hajian , Tarun Souradeep

The two point correlation function of the CMB temperature anisotropies is generally assumed to be statistically isotropic (SI). Deviations from this assumption could be traced to physical or observational artefacts and systematic effects.…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-11 Saurabh Kumar , Aditya Rotti , Moumita Aich , Nidhi Pant , Sanjit Mitra , Tarun Souradeep

Statistical isotropy (SI) has been one of the simplifying assumptions in cosmological model building. Experiments like WMAP and PLANCK are attempting to test this assumption by searching for specific signals in the Cosmic Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-21 Aditya Rotti , Moumita Aich , Tarun Souradeep

We present a general method for Bayesian inference of the underlying covariance structure of random fields on a sphere. We employ the Bipolar Spherical Harmonic (BipoSH) representation of general covariance structure on the sphere. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-04 Santanu Das , Benjamin D. Wandelt , Tarun Souradeep

Mild, unavoidable deviations from circular-symmetry of instrumental beams in current Cosmic Microwave Background (CMB) experiments now pose a significant challenge to deriving high precision inferences from the high sensitivity and…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-22 Nidhi Joshi , Santanu Das , Aditya Rotti , Sanjit Mitra , Tarun Souradeep

Einstein's theory of gravitation that governs the geometry of space-time, coupled with spectacular advance in cosmological observations, promises to deliver a `standard model' of cosmology in the near future. However, local geometry of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Tarun Souradeep
‹ Prev 1 2 3 10 Next ›