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In our previous work we confirmed the reliability of the spherically symmetric Schwarzschild orbit-superposition method to recover the mass and velocity anisotropy profiles of spherical dwarf galaxies. Here we investigate the effect of its…

Astrophysics of Galaxies · Physics 2018-03-14 Klaudia Kowalczyk , Ewa L. Lokas , Monica Valluri

We test the isotropy of the local distribution of galaxies using the 2MASS extended source catalogue. By decomposing the full sky survey into distinct patches and using a combination of photometric and spectroscopic redshift data, we use…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-29 Stephen Appleby , Arman Shafieloo

Consider large signal-plus-noise data matrices of the form $S + \Sigma^{1/2} X$, where $S$ is a low-rank deterministic signal matrix and the noise covariance matrix $\Sigma$ can be anisotropic. We establish the asymptotic joint distribution…

Statistics Theory · Mathematics 2024-01-23 Zeqin Lin , Guangming Pan , Peng Zhao , Jia Zhou

Type Ia supernovae (SNIa) play a central role in constraining the late-time expansion history of the Universe and are directly implicated in current cosmological tensions. Motivated by the possibility of unaccounted redshift-dependent…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-28 Seyed Hamidreza Mirpoorian , Meng-Xiang Lin , Levon Pogosian

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

We study the light scattering of homogenous radially-anisotropic spherical particles. It is shown that radial anisotropy can be employed to tune effectively the electric resonances, and thus enable flexible overlapping of electric and…

Optics · Physics 2023-07-19 Wei Liu

We test the isotropy of Hubble expansion by combining several probes for the first time, constructing full-sky maps of expansion rate variation using Type Ia supernovae, fundamental plane galaxies, and CMB temperature fluctuations. We find…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-04 Alan Junzhe Zhou , Scott Dodelson , Daniel Scolnic

We find statistical evidence for a mismatch between the (global) spatial curvature parameter $K$ in the geodesic equation for incoming photons, and the corresponding parameter in the Friedmann equation that determines the time evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-04 Meir Shimon , Yoel Rephaeli

We examine the Type 1a supernova data in order to determine if it shows any signal of large scale anisotropy. The anisotropy is modelled by an extended G\"{o}del metric, which incorporates expansion along with rotation. The model is…

Astrophysics · Physics 2008-11-26 Pankaj Jain , Moninder S. Modgil , John P. Ralston

The distribution of spin directions of $\sim6.4\cdot10^4$ SDSS spiral galaxies with spectra was examined, and compared to the distribution of $\sim3.3\cdot10^4$ Pan-STARRS galaxies. The analysis shows a statistically significant asymmetry…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-19 Lior Shamir

We use type-Ia supernovae (SNe Ia) discovered by the SDSS-II SN Survey to search for dependencies between SN Ia properties and the projected distance to the host galaxy center, using the distance as a proxy for local galaxy properties…

With the increasing sensitivities of the gravitational wave (GW) detectors and more detectors joining the international network, the chances of detection of a stochastic GW background (SGWB) are progressively increasing. Different…

General Relativity and Quantum Cosmology · Physics 2023-07-06 Jishnu Suresh , Deepali Agarwal , Sanjit Mitra

We decompose Pantheon+ Type Ia supernovae (SN) in hemispheres on the sky finding angular variations up to $4$ km/s/Mpc in the Hubble constant $H_0$ both in the SH0ES redshift range $0.0233 < z < 0.15$ and in extended redshift ranges. The…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-09 Ruairí McConville , Eoin Ó Colgáin

Two-dimensional (2D) tin(II) sulfide (SnS) crystals belong to a class of orthorhombic semiconducting materials that are lately attracting significant interest, given their remarkable properties, such as in-plane anisotropic optical and…

Correctly interpreting observations of sources such as type Ia supernovae (SNe Ia) require knowledge of the power spectrum of matter on AU scales - which is very hard to model accurately. Because under-dense regions account for much of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 V. C. Busti , R. F. L. Holanda , C. Clarkson

(Abridged) We study the properties of anisotropic and axisymmetric velocity ellipsoids from maps of the gas velocity dispersion in nearby galaxies. This data allow us to measure the azimuthal-to-radial axis ratio of gas velocity ellipsoids,…

Astrophysics of Galaxies · Physics 2020-08-05 Laurent Chemin , Jonathan Braine , Françoise Combes , Zacharie S. Kam , Claude Carignan

There currently exist many observations which are not consistent with the cosmological principle. We review these observations with a particular emphasis on those relevant for Square Kilometre Array (SKA). In particular, several different…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-03 Shamik Ghosh , Pankaj Jain , Gopal Kashyap , Rahul Kothari , Sharvari Nadkarni-Ghosh , Prabhakar Tiwari

We show how spectra of Type Ia supernovae (SNe Ia) at maximum light can be used to improve cosmological distance estimates. In a companion article, we used manifold learning to build a three-dimensional parameterization of the intrinsic…

This paper describes the most accurate analytical frequentist assessment to date of the uncertainties in the estimation of physical parameters from gravitational waves generated by non spinning binary systems and Earth-based networks of…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Salvatore Vitale , Michele Zanolin

We propose a robust, quantitative method to compare the synthetic light curves of a Type Ia Supernova (SNIa) explosion model with a large set of observed SNeIa, and derive a figure of merit for the explosion model's agreement with…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-05 Benedikt Diemer , Richard Kessler , Carlo Graziani , George C. Jordan , Donald Q. Lamb , Min Long , Daniel R. van Rossum
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