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Cosmography is a phenomenological and relatively model-independent approach to cosmology, where physical quantities are expanded as a Taylor series in the cosmological redshift, or in related variables. Here we apply this methodology to…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-08 C. J. A. P. Martins , F. P. S. A. Ferreira , P. V. Marto

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…

Astrophysics · Physics 2009-10-30 G. Efstathiou , J. R. Bond

We explore transformations of the Friedman-Lema\^itre-Robertson-Walker (FLRW) metric and cosmological parameters that align with observational data, aiming to gain insights into potential extensions of standard cosmological models. We…

We forecast the ability of cosmic microwave background (CMB) temperature and polarization datasets to constrain theories of eternal inflation using cosmic bubble collisions. Using the Fisher matrix formalism, we determine both the overall…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-21 Stephen M. Feeney , Franz Elsner , Matthew C. Johnson , Hiranya V. Peiris

The state-of-the-art in semantic segmentation is currently represented by fully convolutional networks (FCNs). However, FCNs use large receptive fields and many pooling layers, both of which cause blurring and low spatial resolution in the…

Computer Vision and Pattern Recognition · Computer Science 2016-05-26 Gedas Bertasius , Jianbo Shi , Lorenzo Torresani

The success of present and future cosmological studies is tied to the ability to detect discrepancies in complex data sets within the framework of a cosmological model. Tensions caused by the presence of unknown systematic effects need to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-13 Marco Raveri , Wayne Hu

We study the statistics of weak lensing convergence peaks, such as their abundance and two-point correlation function (2PCF), for a wide range of cosmological parameters $\Omega_m$ and $\sigma_8$ within the standard $\Lambda$CDM paradigm,…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-08 Christopher T. Davies , Marius Cautun , Baojiu Li

Bayesian inference in the physical sciences faces a fundamental challenge: the imperative for high-fidelity physical modeling often clashes with the intrinsic limitations of stochastic sampling algorithms. Complex, high-dimensional…

Instrumentation and Methods for Astrophysics · Physics 2026-04-09 Bo Liang , Chang Liu , Hanlin Song , Tianyu Zhao , Minghui Du , He Wang , Haohao Gu , Sensen He , Yuxiang Xu , Wei-Liang Qian , Li-e Qiang , Peng Xu , Ziren Luo , Mingming Sun

We make the hypothesis that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding universe. We show that solving Friedman's equations with that…

Astrophysics · Physics 2009-06-23 J. -M. Vigoureux , P. Vigoureux , B. Vigoureux

Fractional differential calculus is a mathematical tool that has found applications in the study of social and physical behaviors considered ``anomalous''. It is often used when traditional integer derivatives models fail to represent cases…

General Relativity and Quantum Cosmology · Physics 2024-05-07 Kevin Marroquín , Genly Leon , Alfredo D. Millano , Claudio Michea , Andronikos Paliathanasis

Measuring small separations between two optical sources, either in space or in time, constitute an important metrological challenge as standard intensity-only measurements fail for vanishing separations. Contrarily, it has been established…

Fractional calculus is an effective tool in incorporating the effects of non-locality and memory into physical models. In this regard, successful applications exist rang- ing from signal processing to anomalous diffusion and quantum…

General Physics · Physics 2014-08-26 S. S. Bayin , J. P. Krisch

We consider two-dimensional chiral, first-order conformal field theories governing maps from the Riemann sphere to the projective light cone inside Minkowski space -- the natural setting for describing conformal field theories in two fewer…

High Energy Physics - Theory · Physics 2017-09-13 Tim Adamo , Ricardo Monteiro , Miguel F. Paulos

Motivated by recent developments in conformal field theory (CFT), we devise a Quantum Monte Carlo (QMC) method to calculate the moments of the partially transposed reduced density matrix at finite temperature. These are used to construct…

Strongly Correlated Electrons · Physics 2014-08-08 Chia-Min Chung , Vincenzo Alba , Lars Bonnes , Pochung Chen , Andreas M. Läuchli

Einstein equations can be written in the so-called Fully Constrained Formulation (FCF). This formulation has two different sectors: the elliptic sector, formed by the Hamiltonian and Momentum constraints together with the equations derived…

General Relativity and Quantum Cosmology · Physics 2025-07-25 Samuel Santos-Pérez , Isabel Cordero-Carrión , Pablo Cerdá-Durán

Non-Fermi liquids are an important topic in condensed matter physics, as their characteristics challenge the framework of traditional Fermi liquid theory and reveal the complex behavior of electrons in strongly interacting systems. Both the…

Strongly Correlated Electrons · Physics 2025-10-21 Tu Hong , Xiao Yan Xu

Fermi edge adsorption singularities (FES) are studied using a combination of conformal field theory (CFT), an exact sum rule and numerical work on a tight binding model which is shown to exhibit remarkable simplifying features. The…

Condensed Matter · Physics 2009-10-30 Alexandre M. Zagoskin , Ian Affleck

Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z$\simeq 10^7$. Unfortunately all the attempts so far carried out…

Instrumentation and Methods for Astrophysics · Physics 2017-02-22 Giorgio Sironi

While the standard, six-parameter, spatially flat $\Lambda$CDM model has been highly successful, certain anomalies in the cosmic microwave background bring out a tension between this model and observations. The statistical significance of…

General Relativity and Quantum Cosmology · Physics 2021-09-21 Abhay Ashtekar , Brajesh Gupt , V. Sreenath

A proof is given that the maximal Fermi coordinate chart for any comoving observer in a broad class of Robertson-Walker spacetimes consists of all events within the cosmological event horizon, if there is one, or is otherwise global. Exact…

Mathematical Physics · Physics 2015-07-10 David Klein