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In this paper, we investigate the cosmic anisotropy from the SN-Q sample, consisting of the Pantheon sample and quasars, by employing the hemisphere comparison (HC) method and the dipole fitting (DF) method. Compared to the Pantheon sample,…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 J. P. Hu , Y. Y. Wang , F. Y. Wang

We point out that particles accelerated in a non-relativistic shock of compression ratio $r$ attain the standard, $p=(r+2)/(r-1)$ spectral index only under certain conditions. Previous derivations of the spectrum, based on the…

High Energy Astrophysical Phenomena · Physics 2020-07-07 Uri Keshet , Ofir Arad , Yuri Lyubarski

We present a model-independent test of anisotropy in the cosmic distance duality relation (CDDR), $D_L=(1+z)^2 D_A$, using the Pantheon+ type Ia supernova sample and baryon acoustic oscillation (BAO) data. The angular diameter distance is…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-07 Pushty Shrimankar , Gopal Kashyap

We obtain a complete description of anisotropic scaling limits and the existence of scaling transition for a class of negatively dependent linear random fields on ${\mathbb{Z}}^2$ with moving-average coefficients $a(t,s)$ decaying as…

Probability · Mathematics 2020-03-17 Donatas Surgailis

In this paper we present a shape optimization scheme which utilizes the alternating direction method of multipliers (ADMM) to approximate a direction of steepest descent in $W^{1,\infty}$. The followed strategy is a combination of the…

Optimization and Control · Mathematics 2025-08-26 Philip J. Herbert , Jose A. Pinzon Escobar , Martin Siebenborn

Recent observations suggest that there are violations of the isotropy of the universe at large scales, an important part of the cosmological principle. In this paper, we use the Cosmic Microwave Background (CMB) data to search for spatial…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-20 Shek Yeung , Ming-Chung Chu

We investigate what current cosmological data tells us about the cosmological expansion rate in a model independent way. Specifically, we study if the expansion was decelerating at high redshifts and is accelerating now, without referring…

Astrophysics · Physics 2009-11-13 Edvard Mortsell , Chris Clarkson

This short note provides a large-deviation-based upper bound on the growth rate of directed last passage percolation (LPP) using the entropy of the normalized direction vector.

Information Theory · Computer Science 2019-10-15 Cihan Tepedelenlioglu

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

The Alternating Direction Method of Multipliers (ADMM) has gained significant attention across a broad spectrum of machine learning applications. Incorporating the over-relaxation technique shows potential for enhancing the convergence rate…

Optimization and Control · Mathematics 2024-01-02 Jintao Song , Wenqi Lu , Yunwen Lei , Yuchao Tang , Zhenkuan Pan , Jinming Duan

In parallel with advances in microscale imaging techniques, the fields of biology and materials science have focused on precisely extracting particle properties based on their diffusion behavior. Although the majority of real-world…

Mesoscale and Nanoscale Physics · Physics 2024-05-22 Kaito Takanami , Daisuke Taniguchi , Sawako Enoki , Masafumi Kuroda , Yasushi Okada , Yoshiyuki Kabashima

We investigate the prospects for determining the accelerating history of the Universe from upcoming measurements of the expansion rate $H(z)$. In our analyses, we use Monte Carlo simulations based on $w$CDM models to generate samples with…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-22 J. C. Carvalho , J. S. Alcaniz

Empirical results show that Anderson acceleration (AA) can be a powerful mechanism to improve the asymptotic linear convergence speed of the Alternating Direction Method of Multipliers (ADMM) when ADMM by itself converges linearly. However,…

Optimization and Control · Mathematics 2020-12-01 Dawei Wang , Yunhui He , Hans De Sterck

We present the first detailed data of the momentum-resolved, temperature dependence of the superconducting gap of $Bi_{2}Sr_{2}Ca_{1}Cu_{2}O_{8+x}$, complemented by similar data on the intensity of the photoemission superconducting…

Condensed Matter · Physics 2016-08-14 Jian Ma , C. Quitmann , R. J. Kelley , H. Berger , G. Margaritondo , M. Onellion

We extend the previously described CMB Gibbs sampling framework to allow for exact Bayesian analysis of anisotropic universe models, and apply this method to the 5-year WMAP temperature observations. This involves adding support for…

Astrophysics · Physics 2011-02-11 Nicolaas E. Groeneboom , Hans Kristian Eriksen

The energy conditions provide a very promising model-independent study of the current acceleration of the universe. However, in order to connect these conditions with observations, one often needs first to integrate them, and then find the…

Astrophysics · Physics 2009-06-23 Yungui Gong , Anzhong Wang

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

Recent astronomical observations show that the universe may be anisotropic on large scales. The Union2 SnIa data hint that the universe has a preferred direction. If such a cosmological privileged axis indeed exists, one has to consider an…

General Relativity and Quantum Cosmology · Physics 2019-07-03 Amin Salehi , S. Aftabi

The anisotropy associated with the initial dipole asymmetry in heavy ion collisions is studied via the two-particle relative azimuthal azimuthal angle (\Delta\phi=\phi^a-\phi^b) correlations, within a multi-phase transport model. For a…

Nuclear Theory · Physics 2013-09-17 Jiangyong Jia , Sooraj K. Radhakrishnan , Soumya Mohapatra

The isotropy of the universal Hubble expansion is a fundamental tenet of physical cosmology, but it has not been precisely tested during the current epoch, when dark energy is dominant. Anisotropic expansion will produce a shearing velocity…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Jeremy Darling