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Related papers: Redshift drift cosmography for model-independent c…

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In this paper, we use the Cosmokinematics approach to study the accelerated expansion of the Universe. This is a model independent approach and depends only on the assumption that the Universe is homogeneous and isotropic and is described…

General Relativity and Quantum Cosmology · Physics 2016-01-06 Nisha Rani , Deepak Jain , Shobhit Mahajan , Amitabha Mukherjee , Nilza Pires

If we assume that we live in the center of a spherical inhomogeneous universe, we can explain the apparent accelerating expansion of the universe without introducing the unknown dark energy or modifying gravitational theory. Direct…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Kent Yagi , Atsushi Nishizawa , Chul-Moon Yoo

A major issue in contemporary cosmology is the persistent discrepancy, known as the Hubble tension, between the Hubble constant ($H_0$) estimates from local measurements and those inferred from early-Universe observations under the standard…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-29 Surajit Kalita , Akhil Uniyal , Tomasz Bulik , Yosuke Mizuno

Data-driven approaches play a crucial role in space computing, and our paper focuses on analyzing data to learn more about celestial objects. Photometric redshift, a measure of the shift of light towards the red part of the spectrum, helps…

Instrumentation and Methods for Astrophysics · Physics 2024-11-22 Krishna Chunduri , Mithun Mahesh

The evolution of the dark energy parameter within the scope of a spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with perfect fluid and dark energy components is studied by generalizing the recent results…

General Physics · Physics 2014-03-11 Anirudh Pradhan

Measurements of the redshift drift -- the real time variation of the redshift of distance sources -- are expected in the next couple of decades using next generation facilities such as the ANDES spectrograph at the ELT and the SKAO survey.…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-18 Pedro Bessa , Valerio Marra , Tiago Castro

We present a new test of the validity of the Friedmann-Lemaitre-Robertson-Walker (FLRW) metric, based on comparing the distance from redshift 0 to $z_1$ and from $z_1$ to $z_2$ to the distance from $0$ to $z_2$. If the universe is described…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Syksy Rasanen , Krzysztof Bolejko , Alexis Finoguenov

Based upon the intrinsic symmetries approach to inhomogeneous cosmologies, we propose an exact solution to Einstein's field equations where the spatial sections are flat and the source is a non-perfect fluid such that the dissipative terms…

General Relativity and Quantum Cosmology · Physics 2021-03-11 E. Bittencourt , L. G. Gomes , G. B. Santos

This paper explores models of the FLRW universe that incorporate a time-varying cosmological term $\Lambda(t)$. Specifically, we assume a power-law form for the cosmological term as a function of the scale factor: $\Lambda(t)=\Lambda_{0}…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 M. Koussour , N. Myrzakulov , J. Rayimbaev

Is the Doppler interpretation of galaxy redshifts in a Friedmann-Lemaitre-Robertson-Walker (FLRW) model valid in the context of the approach to comoving spatial sections pioneered by de Sitter, Friedmann, Lemaitre and Robertson, i.e.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Boudewijn F. Roukema

The exploration of the redshift drift, a direct measurement of cosmological expansion, is expected to take several decades of observation with stable, sensitive instruments. We introduced a new method to probe cosmology which bypasses the…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Chengyi Wang , Krzysztof Bolejko , Geraint F. Lewis

We explore whether an independent determination of the distance-redshift relation, and hence cosmological model parameters, can be obtained from the apparent correlations between two different waveband luminosities or fluxes, as has been…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-18 V. Petrosian , J. Singal , S. Mutchnick

When photons from distant galaxies and stars pass through our neighboring environment, the wavelengths of the photons would be shifted by our local gravitational potential. This local gravitational redshift effect can potentially have an…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Haoting Xu , Zhiqi Huang , Na Zhang , Yundong Jiang

Our observations of the Universe are fundamentally anisotropic, with data from galaxies separated transverse to the line of sight coming from the same epoch while that from galaxies separated parallel to the line of sight coming from…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Eric V. Linder , MinJi Oh , Teppei Okumura , Cristiano G. Sabiu , Yong-Seon Song

We present a suite of cosmological N-body simulations describing the "Running Friedmann-Lema{\"i}tre-Robertson-Walker" (R-FLRW) cosmological model. This model is based on quantum field theory in a curved space-time and extends {\Lambda}CDM…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-25 Antonio Bibiano , Darren J. Croton

We explore the distance-redshift relation using a cosmographic methodology, and show how the cosmographic parameters can be used to determine the redshift of transition from deceleration to acceleration. Such a transition at a low redshift…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-02 Daniel Muthukrishna , David Parkinson

The present matter density of the Universe, while highly inhomogeneous on small scales, displays approximate homogeneity on large scales. We propose that whereas it is justified to use the Friedmann-Lemaitre-Robertson-Walker (FLRW) line…

Astrophysics · Physics 2008-11-26 Aseem Paranjape , T. P. Singh

It is argued that cosmic chronometers yield estimates of the spatially averaged expansion rate even in a universe that is not well described by a global FLRW model - as long as the Universe is statistically homogeneous and isotropic with a…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-11 S. M. Koksbang

Cosmography, as an integral branch of cosmology, strives to characterize the Universe without relying on pre-determined cosmological models. This model-independent approach utilizes Taylor series expansions around the current epoch,…

General Physics · Physics 2024-06-11 Seokcheon Lee

The quantized Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) model minimally coupled to a free massless scalar field is studied and interpreted in the Bohm-de Broglie framework. We analyze the quantum bohmian trajectories corresponding to…

General Relativity and Quantum Cosmology · Physics 2016-11-09 E. Sergio Santini
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