Roya Mohayaee's research while affiliated with University of Oxford and other places
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Publications (89)
A weighted, semidiscrete, fast optimal transport (OT) algorithm for reconstructing the Lagrangian positions of protohalos from their evolved Eulerian positions is presented. The algorithm makes use of a mass estimate of the biased tracers and of the distribution of the remaining mass (the “dust”) but is robust to errors in the mass estimates. Tests...
In view of the growing tension between the dipole anisotropy of number counts of cosmologically distant sources and of the cosmic microwave background (CMB), we investigate the number count dipole induced by primordial perturbations with wavelength comparable to or exceeding the Hubble radius today. First, we find that neither adiabatic nor isocurv...
We present the first joint analysis of catalogs of radio galaxies and quasars to determine whether their sky distribution is consistent with the standard ΛCDM model of cosmology. This model is based on the cosmological principle, which asserts that the universe is statistically isotropic and homogeneous on large scales, so the observed dipole aniso...
In view of the growing tension between the dipole anisotropy of number counts of cosmologically distant sources and of the cosmic microwave background (CMB), we investigate the number count dipole induced by primordial perturbations with wavelength comparable to or exceeding the Hubble radius today. First, we find that neither adiabatic nor isocurv...
We present the first joint analysis of catalogs of radio galaxies and quasars to determine if their sky distribution is consistent with the standard $\Lambda$CDM model of cosmology. This model is based on the cosmological principle, which asserts that the universe is isotropic and homogeneous on large scales, so the observed dipole anisotropy in th...
Optimal transport theory has recently re-emerged as a vastly resourceful field of mathematics with elegant applications across physics and computer science. Harnessing methods from geometry processing, we report on the efficient implementation for a specific problem in cosmology-the reconstruction of the linear density field from low redshifts, in...
A 10% difference in the scale for the Hubble parameter constitutes a clear problem for cosmology. Here, considering angular distribution of type Ia supernovae (SN) within the Pantheon compilation and working within flat ΛCDM cosmology, we observe a correlation between higher H0 and the CMB dipole direction, confirming our previous results for stron...
A model-independent, weighted semi-discrete, fast optimal transport algorithm to reconstruct the Lagrangian positions of proto-halos from their evolved Eulerian positions is presented. Tests with state-of-art cosmological simulations show that the positions of proto-halos are reconstructed accurately, without having to assume a background cosmology...
Optimal transport theory has recently reemerged as a vastly resourceful field of mathematics with elegant applications across physics and computer science. Harnessing methods from geometry processing, we report on the efficient implementation for a specific problem in cosmology -- the reconstruction of the linear density field from low redshifts, i...
The tension between early and late Universe probes of the Hubble constant has motivated various new FLRW cosmologies. Here, we reanalyse the Hubble tension with a recent age of the Universe constraint. This allows us to restrict attention to matter and a dark energy sector that we treat without assuming a specific model. Assuming analyticity of the...
In the late 1990’s, observations of two directionally-skewed samples of, in total, 93 Type Ia supernovae were analysed in the framework of the Friedmann–Lemaître–Robertson–Walker (FLRW) cosmology. Assuming these to be ‘standard(isable) candles’ it was inferred that the Hubble expansion rate is accelerating as if driven by a positive Cosmological Co...
We leverage powerful mathematical tools stemming from optimal transport theory and transform them into an efficient algorithm to reconstruct the fluctuations of the primordial density field, built on solving the Monge-Ampère-Kantorovich equation. Our algorithm computes the optimal transport between an initial uniform continuous density field, parti...
![Fig. 2. Sky distribution of the SNe Ia used by the HZT [10] (left) and...](publication/352209319/figure/fig2/AS:1032265295482881@1623122633815/Sky-distribution-of-the-SNe-Ia-used-by-the-HZT-10-left-and-the-SCP-9-right_Q320.jpg)
In the late 1990's, observations of 93 Type Ia supernovae were analysed in the framework of the FLRW cosmology assuming these to be `standard(isable) candles'. It was thus inferred that the Hubble expansion rate is accelerating as if driven by a positive Cosmological Constant $\Lambda$. This is still the only direct evidence for the `dark energy' t...
A 10\% difference in the scale for the Hubble parameter constitutes a clear problem for cosmology. As recently observed \cite{Krishnan:2021dyb}, only a modification to early Universe physics remains as a resolution within Einstein gravity plus the Friedmann-Lema\^itre-Robertson-Walker (FLRW) paradigm, but the current approaches are unconvincing, si...
The tension between early and late Universe probes of the Hubble constant has motivated various new FLRW cosmologies. Here, we reanalyse the Hubble tension with a recent age of the Universe constraint. This allows us to restrict attention to matter and a dark energy sector that we treat without assuming a specific model. Assuming analyticity of the...
We study the large-scale anisotropy of the universe by measuring the dipole in the angular distribution of a flux-limited, all-sky sample of 1.36 million quasars observed by the Wide-field Infrared Survey Explorer (WISE). This sample is derived from the new CatWISE2020 catalog, which contains deep photometric measurements at 3.4 and 4.6 μ m from th...
We leverage powerful mathematical tools stemming from optimal transport theory and transform them into an efficient algorithm to reconstruct the fluctuations of the primordial density field, built on solving the Monge-Amp\`ere-Kantorovich equation. Our algorithm computes the optimal transport between an initial uniform continuous density field, par...
We study the large-scale anisotropy of the Universe by measuring the dipole in the angular distribution of a flux-limited, all-sky sample of 1.3 million quasars observed by the Wide-field Infrared Survey Explorer (WISE). This sample is derived from the new CatWISE2020 catalog, which contains deep photometric measurements at 3.4 and 4.6 um from the...
Using fully GPU N-body simulations, we demonstrate for the first time that subhaloes sink and transfer energy via dynamical friction into the centres of dwarf galaxies. This dynamical heating kicks any central massive black hole out to tens of parsecs, especially at early epochs (z = 1.5–3). This mechanism helps explain the observed off-centre blac...
We study correlated fluctuations of Type~Ia supernova observables due to peculiar velocities of both the observer and the supernova host galaxies, and their impact on cosmological parameter estimation. We demonstrate using the CosmicFlows-3 dataset that at low redshifts the corrections for peculiar velocities in the JLA catalogue have been systemat...
We performed a series of high-resolution N-body simulations to examine whether dark matter candidates in the form of primordial black holes (PBHs) can solve the cusp–core problem in low-mass dwarf galaxies. If some fraction of the dark matter in low-mass dwarf galaxies consists of PBHs and the rest is cold dark matter, dynamical heating of the cold...
Using fully GPU $N$-body simulations, we demonstrate for the first time that subhalos sink and transfer energy via dynamical friction into the centres of dwarf galaxies. This dynamical heating kicks any central massive black hotel (MBH) out to tens of parsecs, especially at early epochs ($z$=1.5-3). This mechanism helps explain the observed off-cen...
We use a fully GPU N-body code to demonstrate that dark matter (DM) minihaloes, as a new component of globular clusters (GCs), resolve both the timing and cusp–core problems in Fornax if the (five or six) GCs were recently accreted (≤3 Gyr ago) by Fornax. Under these assumptions, infall of these GCs does not occur and no star clusters form in the c...
We run state-of-the-art high resolution fully GPU N-body simulations to show that M31 harbours a dark matter core. Observational data in the inner halo of M31 provide stringent constraints on the initial conditions of our simulations. We demonstrate that an infalling satellite on a highly eccentric orbit is at the origin of the giant stellar stream...
We have shown (Colin et al. 2019) that the acceleration of the Hubble expansion rate inferred from Type Ia supernovae is essentially a dipole with 3.9$\sigma$ significance, approximately aligned with the CMB dipole, while its monopole component which may be interpreted as due to a Cosmological Constant (or more generally dark energy) is consistent...
Observations reveal a “bulk flow” in the local Universe which is faster and extends to much larger scales than are expected around a typical observer in the standard ΛCDM cosmology. This is expected to result in a scale-dependent dipolar modulation of the acceleration of the expansion rate inferred from observations of objects within the bulk flow....
We use a fully GPU $N$-body code to demonstrate that dark matter minihalos, as a new component of globular clusters, resolves both the timing and cusp-core problems in Fornax if the five globular clusters were recently accreted (2-4 Gyr ago) by Fornax. Under these assumptions, the infall of these globular clusters does not occur and no star cluster...
We use a high performance fully GPU $N$-body code with adaptive time steps to show that dark matter candidates in the form of primordial black holes can induce a cusp-to-core transition in low-mass dwarf galaxies via dynamical friction by dark matter particles at 1 M$_{\odot}$ mass resolution acting on primordial black holes in the mass range 25 -...
We re-investigate the Fornax cusp-core problem using observational results on the spatial and mass distributions of globular clusters (GCs) in order to put constraints on the dark matter profile. We model Fornax using high-resolution N-body simulations with entirely live systems, i.e. self-gravitating systems composed of stars and dark matter, whic...
Recent observations reveal a bulk flow in the local Universe which is faster and extends to larger scales than is expected around a typical observer in the standard $\Lambda$CDM cosmology. The deceleration parameter $q_0$ derived from local observations is then expected to show a scale-dependent dipolar modulation. From a maximum likelihood analysi...
Fornax is the most massive of the Milky Way dwarf spheroidal galaxies and has five globular clusters orbiting in a dense background of dark matter. Observational analyses suggest that globular clusters were initially much more massive and lost most of their stars to the Fornax field. We re-investigate the Fornax cusp-core problem, to clarify tensio...
Previous studies have shown that our velocity in the rest frame of galaxies at high redshift does not converge to that deduced from the CMB temperature-dipole anisotropy. In this work we determine the dipole in the galaxy catalogue derived from the Wide-field Infrared Survey Explorer (WISE) survey. After reducing star contamination to ~0.1% by reje...
Previous studies have found our velocity in the rest frame of radio galaxies at high redshift to be substantially larger than that inferred from the CMB temperature dipole anisotropy. We construct a full sky catalogue NVSUMSS, by merging the NVSS and SUMSS catalogues and removing local sources by various means including cross-correlating with the 2...
The existence of critical points for the peculiar velocity field is a natural feature of the correlated vector field. These points appear at the junctions of velocity domains with different orientations of their averaged velocity vectors. Since peculiar velocities are the important cause of the scatter in the Hubble expansion rate, we propose that...
The existence of critical points for the peculiar velocity field is a natural feature of the correlated vector field. These points appear at the junctions of velocity domains with different orientations of their averaged velocity vectors. Since peculiar velocities are the important cause of the scatter in the Hubble expansion rate, we propose that...
The existence of critical points for the peculiar velocity field is a natural feature of the correlated vector field. These points appear in contact zones of the velocity domains with different orientation of the averaged velocity vector. At the same time peculiar velocities are the cause of the scatter of the Hubble expansion rate. We propose that...
We propose a new probe to test the nature of gravity at various redshifts
through large-scale cosmological observations. We use our void catalog,
extracted from the Sloan Digital Sky Survey (SDSS, DR10), to trace the
distribution of matter along the lines of sight to SNe Ia that are selected
from the Union 2 catalog. We study the relation between S...
We propose that the accretion of a dwarf spheroidal galaxy provides a common origin for the giant southern stream and the
warp of M31. We run about 40 full N-body simulations with live M31, infalling galaxies with varying masses and density profiles, and cosmologically plausible
initial orbital parameters. Good agreement with a full range of observ...
We present catalogues of voids for the SDSS DR7 redshift survey and for
Millennium I simulation mock data. We aim to compare the observations with
simulations based on a $\Lambda$CDM model and a semi-analytic galaxy formation
model. We use the void statistics as a test for these models. We assembled a
mock catalogue that closely resembles the SDSS...
We establish a refined version of the Second Law of Thermodynamics for Langevin stochastic processes describing mesoscopic systems driven by conservative or non-conservative forces and interacting with thermal noise. The refinement is based on the Monge-Kantorovich optimal mass transport and becomes relevant for processes far from quasi-stationary...
Dual active galactic nuclei (AGNs) are natural byproducts of hierarchical mergers of galaxies in the ΛCDM cosmogony. Recent observations have shown that only a small fraction (~0.1%-2.5%) of AGNs at redshift z 0.3 are dual with kpc-scale separations, which is rather low compared to the high merger rate of galaxies. Here we construct a phenomenologi...
We carry out fully three-dimensional simulations of evolution from self-similar, spherically symmetric linear perturbations of a cold dark matter (CDM)-dominated Einstein–de Sitter universe. As a result of the radial orbit instability, the haloes which grow from such initial conditions are triaxial with major-to-minor axial ratios of the order of 3...
Dark matter substructures around nearby galaxies provide an interesting opportunity for confusion-free indirect detection
of dark matter. We calculate the boost over a smooth background distribution of dark matter for gamma-ray emission from dark
matter self-annihilations in tidal structures in M31, assuming a cross-section inversely proportional t...
Dual AGNs are natural byproducts of hierarchical mergers of galaxies in the
LambdaCDM cosmogony. Recent observations have shown that only a small fraction
(~ 0.1%-1%) of AGNs at redshift z<~ 0.3 are dual with kpc-scale separations,
which is rather low compared to the high merger rate of galaxies. Here we
construct a phenomenological model to estima...
The question of the transition to global isotropy from our anisotropic local universe is studied using the Union 2 catalogue
of Type Ia supernovae (SNe Ia). We construct a ‘residual’ statistic sensitive to systematic shifts in their brightness in
different directions and use this to search in different redshift slices for a preferred direction on t...
We generate the peculiar velocity field for the Two Micron All-Sky Redshift Survey (2MRS) catalog using an orbit-reconstruction algorithm. The reconstructed velocities of individual objects in 2MRS are well correlated with the peculiar velocities obtained from high-precision observed distances within 3000 km s–1. We estimate the mean matter density...
We develop a theoretical framework for describing the hierarchical structure of the phase space of cold dark matter haloes, due to gravitationally bound substructures. Because it includes the full hierarchy of the cold dark matter initial conditions and is hence complementary to the halo model, the stable clustering hypothesis is applied for the fi...
We simulate the growth of isolated dark matter haloes from self-similar and spherically symmetric initial conditions. Our N-body code integrates the geodesic deviation equation in order to track the streams and caustics associated with individual simulation particles. The radial orbit instability causes our haloes to develop major-to-minor axis rat...
Most of the mass content of dark matter haloes is expected to be in the form of tidal debris. The density of debris is not constant, but rather can grow due to formation of caustics at the apocenters and pericenters of the orbit, or decay as a result of phase mixing. In the phase space, the debris assemble in a hierarchy which is truncated by the p...
Motion of a continuous fluid can be decomposed into an “incompressible” rearrangement, which preserves the volume of each infinitesimal fluid element, and a gradient map that transfers fluid elements in a way unaffected by any pressure or elasticity (the polar decomposition of Y. Brenier). The Euler equation describes a system whose kinematics is d...
Anisotropic emission of gravitational waves during the merger of black holes induces a recoil velocity on the centre of mass of the binary and the final merger product can then be ejected from its host galaxy. We consider ejected black holes which stay on bound orbits around their host haloes. A recoiled black hole which moves on an almost radial o...
Gravitational collapse of dark matter, merger of dark matter haloes and tidal disruption of satellites are among processes
which lead to the formation of fine and dense dark matter shells, also known as dark matter caustics. The putative weakly
interacting species which may form the dark matter are expected to strongly annihilate in these dense reg...
A new scenario for the emission of high-energy gamma-rays from dark matter annihilation around massive black holes is presented. A black hole can leave its parent halo, by means of gravitational radiation recoil, in a merger event or in the asymmetric collapse of its progenitor star. A recoiled black hole which moves on an almost-radial orbit outsi...
The peculiar velocity reconstruction methods allow one to have a deeper insight into the distribution of dark matter: both to measure mean matter density and to obtain the primordial density fluctuations. We present here the Monge-Ampere-Kantorovitch method applied to mock catalogues mimicking in both redshift and distance catalogues. After having...
Lagrangian reconstruction of large-scale peculiar velocity fields can be strongly affected by observational biases. We develop a thorough analysis of these systematic effects by relying on specially selected mock catalogues. For the purpose of this paper, we use the MAK reconstruction method, although any other Lagrangian reconstruction method shou...
Cold dark matter haloes are populated by caustics, which are yet to be resolved in N-body simulations or observed in the Universe. Secondary infall model provides a paradigm for the study of caustics in "typical" haloes assuming that they have had no major mergers and have grown only by smooth accretion. This is a particular characteristic of the s...
The peculiar velocities of a large number of galaxies can be uniquely reconstructed using present redshift surveys. Our method, based on minimisation of Euler‐Lagrange action, performs extremely well when tested against simulations. We apply our method to the updated NBG redshift
galaxy catalogue and reconstruct the peculiar velocity field in our...
Peculiar velocity reconstruction methods allow one to have a deeper insight into the distribution of dark matter: both to measure Omega_m and to characterize the primordial density fluctuations. We present here the Monge-Ampère-Kantorovitch method applied to redshift reconstruction. We show what are the limitations and the problems to overcome to p...
The peculiar velocities of a large number of galaxies can be uniquely reconstructed using present redshift surveys. Our method, based on minimisation of Euler-Lagrange action, performs extremely well when tested against simulations. We apply our method to the updated NBG redshift galaxy catalogue and reconstruct the peculiar velocity field in our l...
Caustics are formally singular structures, with infinite density, that form in collisionless media. The non-negligible velocity dispersion of dark matter particles renders their density finite. We evaluate the maximum density of the caustics within the framework of secondary infall model of formation of dark matter haloes. The result is then used t...
Peculiar velocities thoughout the region of the local supercluster are reconstructed by two different orbit-retracing methods. The requirement of the optimal correlation between the radial components of reconstructed velocities and the observed peculiar velocities derived from our extensive new catalog of distances puts stringent constraints on the...
Caustics are high-density structures that form frequently in collisionless media. Under self-gravity, cold dark matter flows focus onto caustics which are yet to be resolved in numerical simulations and or observed in the real world. If detected, caustics would provide a strong evidence for dark matter and would rule out alternative models such as...
Caustics are high-density structures that form frequently in collisionless media. Under self-gravity, cold dark matter flows focus onto caustics which are yet to be resolved in numerical simulations and or observed in the real world. If detected, caustics would provide a strong evidence for dark matter and would rule out alternative models such as...
Cold dark matter haloes are populated by high-density structures with sharply peaked profiles known as caustics, which have
not yet been resolved by three-dimensional numerical simulations. Here, we derive semi-analytic expressions for the density
profiles near caustics in haloes that form by self-similar accretions of dark matter with infinitesima...
The Monge–Ampère–Kantorovich (MAK) reconstruction is tested against cosmological N-body simulations. Using only the present mass distribution sampled with particles, and the assumption of homogeneity of the primordial distribution, MAK recovers for each particle the non-linear displacement field between its present position and its Lagrangian posit...
A reconstruction method for recovering the initial conditions of the Universe starting from the present galaxy distribution is presented which guarantees uniqueness of solutions. We show how our method can be used to obtain the peculiar velocities of a large number of galaxies, hence trace galaxies orbits back in time and obtain the entire past dyn...
The observed infall of galaxies into the Virgo cluster puts strong constraints on the mass of the cluster. A non-parametric fully non-linear description of the infall can be made with orbit reconstructions based on Numerical Action Methods. The mass of the cluster is determined to be $1.2 \times 10^{15} M_{\odot}$. The mass-to-light ratio for the c...
We present new results on the angular momentum evolution of dark matter haloes. Haloes, from N-body simulations, are classified according to their mass growth histories into two categories: the accretion category contains haloes whose mass has varied continuously and smoothly, while the merger category contains haloes which have undergone sudden an...
Possible indirect detection of neutralino, through its gamma-ray annihilation product, by the forthcoming GLAST satellite from our galactic halo, M31, M87 and the dwarf galaxies Draco and Sagittarius is studied. Gamma-ray fluxes are evaluated for the two representative energy thresholds, 0.1 GeV and 1.0 GeV, at which the spatial resolution of GLAST...
We show that the deterministic past history of the Universe can be uniquely reconstructed from knowledge of the present mass density field, the latter being inferred from the three-dimensional distribution of luminous matter, assumed to be tracing the distribution of dark matter up to a known bias. Reconstruction ceases to be unique below those sca...
A new method for reconstruction of the primordial density fluctuation
field is presented. Various previous approaches to this problem rendered
non-unique solutions. Here, it is demonstrated that the initial
positions of dark matter fluid elements, under the hypothesis that their
displacement is the gradient of a convex potential, can be reconstruct...
Gravitational clustering of a random distribution of point masses is dominated by the effective short-range interactions due to large-scale isotropy. We introduce a one-dimensional cellular automaton to reproduce this effect in the most schematic way: at each time particles move towards their nearest neighbours with whom they coalesce on collision....
A review of the present observational and theoretical status of elliptical galaxies is presented with the aim to clarify whether the monolithic or the hierarchical, is a more viable scenario for the origin of these structures. We describe the dynamical structure of elliptical galaxies using photometric and spectroscopic data, in particular 3D obser...
Reconstructing the density fluctuations in the early Universe that evolved into the distribution of galaxies we see today is a challenge to modern cosmology. An accurate reconstruction would allow us to test cosmological models by simulating the evolution starting from the reconstructed primordial state and comparing it to observations. Several rec...
The evolution and the statistical properties of an infinite gravitating system represent an interesting and widely investigated subject of research. In cosmology, the standard approach is based on equations of hydrodynamics. In the present paper, we analyze the problem from a different perspective, which is usually neglected. We focus our attention...
The multiscaling behavior of the directed polymers with tilted disorder and Burgers-like turbulence was analyzed. The minimal energy variations of the directed polymer were analyzed to study the structure functions in bifractal Burgers turbulence. The analysis depicted similarity between the multiscaling of discrete counterpart of observed velocity...
A ‘stochastic adhesion’ model is introduced, with the purpose of describing the formation and evolution of mildly non-linear
structures, such as sheets and filaments, in the intergalactic medium (IGM), after hydrogen reionization. The model is based
on replacing the overall force acting on the baryon fluid – which results from the combination of lo...
This paper seeks to check the validity of the "apparent fractal conjecture" (Ribeiro 2001ab: gr-qc/9909093, astro-ph/0104181), which states that the observed power-law behaviour for the average density of large-scale distribution of galaxies arises when some observational quantities, selected by their relevance in average density profile determinat...
We derive the time evolution of the density contrast to all orders of perturbation theory, by solving the Einstein equation for scale-invariant fluctuations. These fluctuations are represented by an infinite series in inverse powers of the radial parameter. In addition to the standard growing modes, we find infinitely many more new growing modes fo...
The evolution of inhomogeneities in a spherical collapse model is studied by expanding the Einstein equation in powers of inverse radial parameter. In the linear regime, the density contrast is obtained for flat, closed and open universes. In addition to the usual modes, an infinite number of new growing modes are contained in the solutions for pre...
We write a non-relativistic Lagrangian for a hierarchical universe. The
equations of motion are solved numerically and the evolution of the fractal
dimension is obtained for different initial conditions. We show that our model
is homogeneous at the time of the last scattering, but evolves into a
self-similar universe with a remarkably constant frac...
Decay amplitudes for mesons in two-dimensional QCD are discussed. We show that in spite of an infinite number of conserved charges, particle production is not entirely suppressed. This phenomenon is explained in terms of quantum corrections to the combined algebra of higher-conserved and spectrum-generating currents. We predict the qualitative form...
It is shown that density fluctuations obey a scaling law in an open Friedmann universe. In a flat universe, the fluctuations are not scale-invariant. We compute the growth rate of adiabatic scale-invariant density fluctuations in flat, open and inflationary universes. We find that, given a sufficiently long time, the density perturbations decay awa...
We use de Vaucouleurs' power-law density-distance relation, to study a hierarchical perturbation of the Friedmann universe. We solve the Einstein equation and obtain the density contrast and the amplification factor for the perturbation. It is shown that, scale-invariant inhomogeneities decay in Einstein-de-Sitter universe. On the contrary, in an o...
The semi-classical phase structure of two-dimensional QED and QCD are briefly reviewed. The non-abelian theory is reformulated to closely resemble the Schwinger model. It is shown that, contrary to the abelian theory, the phase structure of two-dimensional QCD is unaffected by the structure of the theta vacuum. We make parallel calculations in the...
We discuss the issue of screening and confinement of external colour charges in bosonised two-dimensional quantum chromodynamics. Our computation relies on the static solutions of the semi-classical equations of motion. The significance of the different representations of the matter field is explicitly studied. We arrive at the conclusion that the...
Citations
... The observed positions of sources in the sky are therefore affected by the observer velocity. More precisely, the observer velocity with respect to a frame were sources are on average at rest generates a dipole in the source distribution, as computed for example in Mastrogiovanni et al. (2022) for GW events or in Domènech et al. (2022) and Dalang et al. (2022) for galaxy counts. ...
![[object Object]](https://i1.rgstatic.net/ii/profile.image/544953522298880-1506938452951_Q64/Guillem-Domenech-4.jpg)
![[object Object]](https://i1.rgstatic.net/ii/profile.image/277746132504577-1443231246232_Q64/Subir-Sarkar-3.jpg)
... For any large-scale structure distribution, we can always find a frame of reference in which the observer is at rest with respect to the data using a velocity correction. Conventionally observed redshifts are adjusted to place large-scale structure catalogs in the rest frame of the CMB temperature fluctuations, but recent results suggest that high redshift radio sources require a different velocity correction (Secrest et al. 2021(Secrest et al. , 2022. If robust, this apparent breakdown in the cosmological principle highlights the importance of testing standard model assumptions such as isotropy and homogeneity (Aluri et al. 2022). ...
... With future spectroscopic galaxy surveys covering a much larger volume and redshift range, together with expected substantial improvements in the efficiency of BAO reconstruction algorithms (see e.g. [339,340]), this trend is expected to be reversed, with the full-shape information eventually superseding the purely geometrical information (see [148,231,341]). 18 Thus, for what concerns Σm ν bounds, we conclude that P gg (k)-only shape information is approximately as informative as geometrical information from reconstructed BAO peak(s). ...