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Related papers: Cosmic magnification in beyond-Horndeski gravity

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We study cosmic magnification beyond lensing in a late-time universe dominated by quintessence and cold dark matter. The cosmic magnification angular power spectrum, especially going beyond the well-known lensing effect, provides an…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-20 Enas Mohamed , Didam Duniya , Hassan Abdalla , Bishop Mongwane

The beyond-Horndeski gravity has recently been reformulated in the dark energy paradigm - which has been dubbed, Unified Dark Energy (UDE). The evolution equations for the given UDE appear to correspond to a non-conservative dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-15 Didam Duniya , Teboho Moloi , Chris Clarkson , Julien Larena , Roy Maartens , Bishop Mongwane , Amanda Weltman

We study the phenomenology of the beyond Horndeski class of scalar-tensor theories of gravity, which on cosmological scales can be characterised in terms of one extra function of time, $\alpha_{\rm H}$, as well as the usual four Horndeski…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-04 Dina Traykova , Emilio Bellini , Pedro G. Ferreira

f(R) gravity is one of the simplest viable modifications to General Relativity: it passes local astrophysical tests, predicts both the early-time cosmic inflation and the late-time cosmic acceleration, and also describes dark matter. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-22 Didam Duniya , Amare Abebe , Alvaro de la Cruz-Dombriz , Peter Dunsby

Apart from the known weak gravitational lensing effect, the cosmic magnification acquires relativistic corrections owing to Doppler, integrated Sachs-Wolfe, time-delay and other (local) gravitational potential effects, respectively. These…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-14 Didam Duniya

Future observations of the large-scale structure have the potential to investigate cosmological models with a high degree of complexity, including the properties of gravity on large scales, the presence of a complicated dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-26 Robert Reischke , Alessio Spurio Mancini , Björn Malte Schäfer , Philipp M. Merkel

With the advent of gravitational-wave astronomy marked by the aLIGO GW150914 and GW151226 observations, a measurement of the cosmological speed of gravity will likely soon be realized. We show that a confirmation of equality to the speed of…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-02 Lucas Lombriser , Nelson A. Lima

Recent anomalies found in cosmological datasets such as the low multipoles of the Cosmic Microwave Background or the low redshift amplitude and growth of clustering measured by e.g., abundance of galaxy clusters and redshift space…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-24 Emilio Bellini , Antonio J. Cuesta , Raul Jimenez , Licia Verde

Doppler lensing is the apparent change in object size and magnitude due to peculiar velocities. Objects falling into an overdensity appear larger on its near side, and smaller on its far side, than typical objects at the same redshifts.…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-03 David J. Bacon , Sambatra Andrianomena , Chris Clarkson , Krzysztof Bolejko , Roy Maartens

Since the discovery of the accelerated expansion of the present Universe, significant theoretical developments have been made in the area of modified gravity. In the meantime, cosmological observations have been providing more high-quality…

Galaxy surveys contain information on the largest scales via wide-angle and relativistic contributions. By combining two different galaxy populations, we can suppress the strong cosmic variance on ultra-large scales and thus enhance the…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-26 Sheean Jolicoeur , Sêcloka L. Guedezounme , Roy Maartens , Pritha Paul , Chris Clarkson , Stefano Camera

The next generation of surveys will greatly improve our knowledge of cosmological gravity. In this paper we focus on how Stage IV photometric redshift surveys, including weak lensing and multiple tracers of the matter distribution and radio…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-18 David Alonso , Emilio Bellini , Pedro G. Ferreira , Miguel Zumalacarregui

Doppler lensing, a relativistic effect resulting from the peculiar velocities of galaxies along the line of sight, provides insight into the large-scale structure of the Universe. Relativistic simulations are essential for modeling Doppler…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-23 Mubtasim Fuad , Sonia Akter Ema , Md Rasel Hossen

Modifications to gravity can provide attractive alternatives to the dark components of the standard model of cosmology. These modifications to general relativity (GR) must be hidden at small scales where theory is well tested, and so one…

Cosmology and Nongalactic Astrophysics · Physics 2018-02-06 Benjamin Bose

The apparent sizes and brightnesses of galaxies are correlated in a dipolar pattern around matter overdensities in redshift space, appearing larger on their near side and smaller on their far side. The opposite effect occurs for galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-09 Sambatra Andrianomena , Camille Bonvin , David Bacon , Philip Bull , Chris Clarkson , Roy Maartens , Teboho Moloi

Gravitational wave (GW) constraints have recently been used to significantly restrict models of dark energy and modified gravity. New bounds arising from GW decay and GW-induced dark energy instabilities are particularly powerful in this…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-25 Johannes Noller

The observed accelerated expansion of the Universe may be explained by dark energy or the breakdown of general relativity (GR) on cosmological scales. When the latter case, a modified gravity scenario, is considered, it is often assumed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 Jiro Matsumoto , Teppei Okumura , Misao Sasaki

Objects falling into an overdensity appear larger on its near side and smaller on its far side than other objects at the same redshift. This produces a dipolar pattern of magnification, primarily as a consequence of the Doppler effect. At…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-09 Camille Bonvin , Sambatra Andrianomena , David Bacon , Chris Clarkson , Roy Maartens , Teboho Moloi , Philip Bull

One possible way to explain the observed effective dark energy equation of state crossing $w=-1$ (the phantom divide) is through modified gravity. A key point is to not view the expansion history in isolation but to take into account the…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-09 Eric V. Linder

Recent advances, including gravitational wave detections and imaging of black hole shadows, have strongly validated general relativity. Nevertheless, ongoing cosmological observations suggest potential limitations of general relativity,…

General Relativity and Quantum Cosmology · Physics 2025-08-11 Ali Övgün , Mohsen Fathi
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