English
Related papers

Related papers: Detecting the relativistic bispectrum in 21cm inte…

200 papers

The Fourier-space galaxy bispectrum is complex, with the imaginary part arising from leading-order relativistic corrections, due to Doppler, gravitational redshift and related line-of-sight effects in redshift space. The detection of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-05 Roy Maartens , Sheean Jolicoeur , Obinna Umeh , Eline M. De Weerd , Chris Clarkson , Stefano Camera

Measuring relativistic effects on cosmological scales would provide further confirmation of the validity of general relativity in the still poorly tested condition of weak gravity. Despite their relevance, relativistic imprints in the…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-20 Marco Novara , Federico Montano , Stefano Camera

On the scale of the cosmic horizon, signatures that are unique to general relativity are concealed within the statistics of the large scale distribution of galaxies. These were thought to be beyond the reach of all but the most ambitious…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-03 Samantha Josephine Rossiter , Stefano Camera , Federico Montano , Chris Clarkson , Dionysios Karagiannis , Roy Maartens

Next-generation cosmological surveys will observe larger cosmic volumes than ever before, enabling us to access information on the primordial Universe, as well as on relativistic effects. We consider forthcoming 21cm intensity mapping…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-08 Jan-Albert Viljoen , José Fonseca , Roy Maartens

Observations of fluctuations in the redshifted 21 cm radiation from neautral hydrogen (HI) are perceived to be an important future probe of the universe at high redshifts. Under the assumption that at redshifts z less than 6…

Astrophysics · Physics 2009-11-13 Sk. Saiyad Ali , Somnath Bharadwaj , Sanjay K. Pandey

We investigate the future perspectives of the detection of the relativistic dipole by cross-correlating the 21 cm emission in Intensity Mapping (IM) and galaxy surveys at low redshift. We model the neutral hydrogen (HI) and the galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-24 Francesca Lepori , Enea Di Dio , Eleonora Villa , Matteo Viel

We present a method to obtain a high-significance detection of relativistic effects on cosmological scales. Measurements of such effects would be instrumental for our understanding of the Universe, as they would provide a further…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-19 Federico Montano , Stefano Camera

Upcoming galaxy surveys aim to map the Universe with unprecedented precision, depth and sky coverage. The galaxy bispectrum is a prime source of information as it allows us to probe primordial non-Gaussianity (PNG), a key factor in…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-20 Samantha Rossiter , Stefano Camera , Chris Clarkson , Roy Maartens

We explore the information content of 21cm intensity maps in redshift space using the 1-loop Effective Field Theory power spectrum model and the bispectrum at tree level. The 21cm signal contains signatures of dark matter, dark energy and…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 Liantsoa F. Randrianjanahary , Dionysios Karagiannis , Roy Maartens

We study how 21 cm intensity mapping can be used to measure gravitational lensing over a wide range of redshift. This can extend weak lensing measurements to higher redshifts than are accessible with conventional galaxy surveys. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-11 A. Pourtsidou , R. Benton Metcalf

We study the power spectrum dipole of an N-body simulation which includes relativistic effects through ray-tracing and covers the low redshift Universe up to $z_{\rm max} = 0.465$ (RayGalGroup simulation). We model relativistic corrections…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-05 Florian Beutler , Enea Di Dio

Future surveys of large-scale structure will be able to measure perturbations on the scale of the cosmological horizon, and so could potentially probe a number of novel relativistic effects that are negligibly small on sub-horizon scales.…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-08 David Alonso , Philip Bull , Pedro G. Ferreira , Roy Maartens , Mario G. Santos

We study relativistic effects, arising from the light propagation in an inhomogeneous universe. We particularly investigate the effects imprinted in a cross-correlation function between galaxy positions and intrinsic galaxy shapes (GI…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-16 Shohei Saga , Teppei Okumura , Atsushi Taruya , Takuya Inoue

We present a fully relativistic calculation of the observed galaxy number counts in the linear regime. We show that besides the density fluctuations and redshift-space distortions, various relativistic effects contribute to observations at…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Camille Bonvin

In this paper, we study lensing of 21cm intensity mapping (IM). Like in the cosmic microwave background (CMB), there is no first order lensing in intensity mapping. The first effects in the power spectrum are therefore of second and third…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-16 Mona Jalilvand , Elisabetta Majerotto , Ruth Durrer , Martin Kunz

The cross-correlation between 21-cm intensity mapping experiments and photometric surveys of galaxies (or any other cosmological tracer with a broad radial kernel) is severely degraded by the loss of long-wavelength radial modes due to…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-19 Caroline Guandalin , Isabella P. Carucci , David Alonso , Kavilan Moodley

We compute the tree-level bispectrum of 21cm intensity mapping after reionisation. We work in the directly observable angular and redshift space, focusing on equal-redshift correlations and thin redshift bins, for which the lensing…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-10 Ruth Durrer , Mona Jalilvand , Rahul Kothari , Roy Maartens , Francesco Montanari

The redshifted 21cm signal from the post-reionization epoch is highly non-Gaussian; thus, higher-order statistics, such as the bispectrum, are required to extract this non-Gaussian information. However, high-signal-to-noise ratio detection…

Observations of the high-redshift Universe using the 21 cm line of neutral hydrogen and complimentary emission lines from the first galaxies promise to open a new door for our understanding of the epoch of reionization. We present…

Astrophysics of Galaxies · Physics 2019-03-13 Sebastian Dumitru , Girish Kulkarni , Guilaine Lagache , Martin G. Haehnelt

We investigate the feasibility of measuring the effects of peculiar velocities in large-scale structure using the dipole of the redshift-space cross-correlation function. We combine number counts of galaxies with brightness-temperature…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-01 Alex Hall , Camille Bonvin
‹ Prev 1 2 3 10 Next ›