BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Combining the Weyl potential and galaxy velocities: new measuremen ts of E_G DTSTART;VALUE=DATE-TIME:20240711T094500Z DTEND;VALUE=DATE-TIME:20240711T100000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9768@partphys-indico.unige.ch DESCRIPTION:Speakers: Nastassia Grimm (University of Geneva)\nThe novel ob servable \\hat{J}\, capturing the evolution of the combined gravitational potential Ψ + Φ\, provides a powerful and model-independent test of grav ity. As I will demonstrate in this talk\, its full capacity comes into pla y when being combined with further cosmological observables. Together with measurements of the growth of structure \\hat{f}\, accessible via redshif t-space distortions\, the quantity \\hat{J} enables us to reconstruct the so-called E_G statistic. This statistic has been introduced as a robust co nsistency check of general relativity. However\, previous measurements of E_G necessitated a single spectroscopic galaxy sample to measure both gala xy clustering and velocity-density correlations\, to cancel the impact of the galaxy bias. In our recent work (NG\, C. Bonvin & I. Tutusaus\, 2024)\ , we present a novel approach to measuring E_G which is free of this limit ation: It directly combines two model-independent observables - \\hat{f} a nd \\hat{J}. Our method leads to four new measurements of E_G which provid e a considerable improvement in precision compared to previous ones. We fi nd a confirmation of general relativity at three redshifts\, and a mild te nsion of 2.5\\sigma at z=0.47.\n\nhttps://partphys-indico.unige.ch/event/1 441/contributions/9768/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9768/ END:VEVENT BEGIN:VEVENT SUMMARY:Welcome speech DTSTART;VALUE=DATE-TIME:20240709T070000Z DTEND;VALUE=DATE-TIME:20240709T071000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-8953@partphys-indico.unige.ch DESCRIPTION:Speakers: Camille Bonvin ()\nhttps://partphys-indico.unige.ch/ event/1441/contributions/8953/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/8953/ END:VEVENT BEGIN:VEVENT SUMMARY:non-Gaussian biases on CMB lensing reconstruction DTSTART;VALUE=DATE-TIME:20240711T144500Z DTEND;VALUE=DATE-TIME:20240711T150000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9973@partphys-indico.unige.ch DESCRIPTION:Speakers: OMAR DARWISH ()\nWe discuss the impact of non-linear matter clustering and post-Born lensing corrections to CMB lensing recons truction for next generation surveys. In particular\, we will explore the impact of non-Gaussian deflections on Maximum a Posteriori lensing estimat ors\, which are able to provide optimal measurements of the lensing field\ , in contrast to quadratic estimators. Finally\, we will discuss potential ways of mitigating biases.\n\nhttps://partphys-indico.unige.ch/event/1441 /contributions/9973/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9973/ END:VEVENT BEGIN:VEVENT SUMMARY:Registration DTSTART;VALUE=DATE-TIME:20240709T063000Z DTEND;VALUE=DATE-TIME:20240709T070000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9972@partphys-indico.unige.ch DESCRIPTION:https://partphys-indico.unige.ch/event/1441/contributions/9972 / LOCATION:University of Geneva URL:https://partphys-indico.unige.ch/event/1441/contributions/9972/ END:VEVENT BEGIN:VEVENT SUMMARY:Do we understand cosmic structure growth? Insights from new CMB le nsing measurements with the Atacama Cosmology Telescope DTSTART;VALUE=DATE-TIME:20240711T120000Z DTEND;VALUE=DATE-TIME:20240711T123000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9938@partphys-indico.unige.ch DESCRIPTION:Speakers: Blake Sherwin ()\nOne of the most powerful tests of our cosmological model is to verify the predicted growth of large-scale st ructure with time. Intriguingly\, many recent measurements have reported t ensions in such tests of structure growth\, which could hint at systematic errors or even new physics. Motivated by this puzzling situation\, I will present new determinations of cosmic structure growth using CMB gravitati onal lensing measurements from the Atacama Cosmology Telescope (ACT). Thes e ACT DR6 CMB lensing measurements allow us to directly map the dark matte r distribution in projection out to high redshifts\; new cross-correlation s of CMB lensing with unWISE and DESI galaxies also allow us to probe the matter tomographically. I will discuss the implications of our lensing res ults for the validity of our standard cosmological model as well as for ke y cosmological parameters such as the neutrino mass and Hubble constant.\n \nhttps://partphys-indico.unige.ch/event/1441/contributions/9938/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9938/ END:VEVENT BEGIN:VEVENT SUMMARY:Summary Talk DTSTART;VALUE=DATE-TIME:20240712T101500Z DTEND;VALUE=DATE-TIME:20240712T104500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9942@partphys-indico.unige.ch DESCRIPTION:Speakers: Roy Maartens (University of the Western Cape\, South Africa)\nhttps://partphys-indico.unige.ch/event/1441/contributions/9942/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9942/ END:VEVENT BEGIN:VEVENT SUMMARY:The bispectrum of peculiar velocities. DTSTART;VALUE=DATE-TIME:20240710T123000Z DTEND;VALUE=DATE-TIME:20240710T130000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9932@partphys-indico.unige.ch DESCRIPTION:Speakers: Stefano Camera (Universita degli studi di Torino)\nh ttps://partphys-indico.unige.ch/event/1441/contributions/9932/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9932/ END:VEVENT BEGIN:VEVENT SUMMARY:Predicting relativistic effects and constraining local Primordial Non-Gaussianities with galaxy surveys: a few lessons learnt DTSTART;VALUE=DATE-TIME:20240709T081000Z DTEND;VALUE=DATE-TIME:20240709T084000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9937@partphys-indico.unige.ch DESCRIPTION:Speakers: Emanuele Castorina ()\nIn this talk I will review re cent work on understanding the importance of GR effects in the correlation function or power spectrum of spectroscopic data\, with an emphasis on In fra-Red cancellations and their physical meaning. I will then discuss how any quantitative accurate statement about GR effects cannot be made withou t taking into account a large number of observational effects that become important at large scales. Finally\, I will highlight some features of a p ower spectrum analysis searching for local Primordial Non-Gaussianities an d their relation to GR effects.\n\nhttps://partphys-indico.unige.ch/event/ 1441/contributions/9937/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9937/ END:VEVENT BEGIN:VEVENT SUMMARY:Impact of Peculiar Velocities on Color Selection and the Large Sca le Structure of Galaxy Surveys DTSTART;VALUE=DATE-TIME:20240711T093000Z DTEND;VALUE=DATE-TIME:20240711T094500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9774@partphys-indico.unige.ch DESCRIPTION:Speakers: Batia Friedman-Shaw (Perimeter Institute)\nIn this s tudy\, we examine the novel effects of peculiar velocities on color select ion in galaxy surveys\, with a focus on their implications for the analysi s of large-scale structure. Our work quantifies the interplay between the peculiar velocities of Emission Line Galaxies (ELGs) and the color filters employed in the DESI survey. We show that these velocities can shift spec tral emission features into or out of filter bands\, modifying galaxy colo rs and thereby influencing selection criteria. This phenomenon mimics the effect of evolution bias but can exceed it by as much as an order of magni tude. We illustrate that ELGs’ susceptibility to minor spectral shifts i nduced by peculiar velocities stems from their notably intense emission li nes. Our results underscore that peculiar velocities markedly affect the E LG-LRG (Luminous Red Galaxy) multi-tracer dipole power spectrum and also i mpart smaller\, yet significant\, changes to the ELG single tracer statist ics. This work highlights the essential need for careful consideration of spectral-dependent biases caused by peculiar velocities during the selecti on phase of galaxy surveys\, to ensure an unbiased analysis of cosmologica l surveys.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/97 74/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9774/ END:VEVENT BEGIN:VEVENT SUMMARY:Redshift drift as an (almost) model-independent probe of dark ener gy DTSTART;VALUE=DATE-TIME:20240712T080000Z DTEND;VALUE=DATE-TIME:20240712T083000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9936@partphys-indico.unige.ch DESCRIPTION:Speakers: Asta Heinesen (Niels Bohr Institute)\nReal-time meas urements are becoming feasible in cosmology\, where the next generation of telescopes such as the Square Kilometer Array and the Extremely Large Tel escope will detect the temporal change of redshifts of individual sources with a precision that will allow a direct detection of the cosmic expansio n rate. These detections of cosmic drifts of redshifts are likely to becom e cornerstones in modern cosmology\, where one has otherwise relied on the indirect inference of cosmic expansion by estimation of the slope of the fitted distance-redshift relation. Because of the direct inference of the cosmic time-evolution that is in principle possible with redshift drift\, it is a powerful model-independent probe of the kinematics of the Universe . I will present formalism relevant for analysing redshift drift measureme nts model-independently\, i.e.\, free of any explicit metric assumption. I will explain how one can use redshift drift observations to (almost) mode l-independently test for violations of the strong energy condition.\n\nhtt ps://partphys-indico.unige.ch/event/1441/contributions/9936/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9936/ END:VEVENT BEGIN:VEVENT SUMMARY:The Black Hole Universe and Its Connection to the Einstein-Rosen B ridge DTSTART;VALUE=DATE-TIME:20240710T133000Z DTEND;VALUE=DATE-TIME:20240710T140000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9940@partphys-indico.unige.ch DESCRIPTION:Speakers: Enrique Gaztanaga (Institute of Cosmology and Gravit ation\, U. Portsmouth)\nA homogeneous spherical cloud of pressureless matt er \\( M \\) at rest will eventually collapse into a black hole characteri zed by its gravitational radius \\( R_s = 2GM \\). This forms what we term a Black Hole Universe (BHU). The BHU necessitates a boundary term to ensu re that nothing can escape \\( R_s \\). This boundary term modifies Einste in’s field equations by adding a component that behaves identically to t he observed cosmological constant \\(\\Lambda = 3/R_s^2 \\). Furthermore\, we explore the quantum aspects of this boundary\, offering a novel perspe ctive on the Einstein-Rosen bridge. Our findings are supported by measurem ents of parity asymmetry in the Cosmic Microwave Background temperature pe rturbations\, providing empirical evidence for this new theoretical framew ork.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9940/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9940/ END:VEVENT BEGIN:VEVENT SUMMARY:The many faces of scalar-tensor perturbation mixing in Cosmology DTSTART;VALUE=DATE-TIME:20240710T073000Z DTEND;VALUE=DATE-TIME:20240710T080000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9928@partphys-indico.unige.ch DESCRIPTION:Speakers: Sabino Matarrese (Dipartimento di Fisica e Astronomi a G. Galilei\, Università degli Studi di Padova\, Italy)\nGoing beyond li near perturbation theory in cosmology brings several novel phenomena\, amo ng which the unavoidable mixing of scalar and tensor perturbation modes. W hile some of such effects - such as the generation of the so-called Scalar -Induced-Gravitational-Wave background - are nowadays quite popular and la rgerly analyzed\, there are other effects which are less known and deserve attention:\nTensor-Induced-Density-Perturbations\, gravitational waves in duced by scalar-tensor mixing\, effects of scalar modes on the propagation of gravitational waves beyond the geometric optics limit.\nI will review these various faces of non-linear perturbation theory in General Relativit y\, also mentioning some Modified Gravity extensions.\n\nhttps://partphys- indico.unige.ch/event/1441/contributions/9928/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9928/ END:VEVENT BEGIN:VEVENT SUMMARY:Global cosmological anisotropy as a long wavelength perturbation DTSTART;VALUE=DATE-TIME:20240712T073000Z DTEND;VALUE=DATE-TIME:20240712T080000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9939@partphys-indico.unige.ch DESCRIPTION:Speakers: Cyril Pitrou (CNRS\, IAP)\nThe current concordance m odel of cosmology has been extremely successful in constraining the global properties of the universe. However\, it is based on the assumption of st atistical homogeneity and isotropy\, and we are thus lead to test this glo bal geometry. In practice\, it is sufficient to constrain mild anisotropie s\, and I will show how anisotropy can be considered as a special long-wav elength perturbation around a Friedmann-Lemaître space-time. Within this framework\, the same tools can be used to compute the anisotropic and non- stochastic perturbation\, and the statistically isotropic and stochastic o nes\, allowing to test late anisotropy from all cosmological observables.\ n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9939/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9939/ END:VEVENT BEGIN:VEVENT SUMMARY:New observables in large-scale structure DTSTART;VALUE=DATE-TIME:20240710T070000Z DTEND;VALUE=DATE-TIME:20240710T073000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9935@partphys-indico.unige.ch DESCRIPTION:Speakers: David Bacon (University of Portsmouth)\nIn this talk I will discuss several new probes and considerations for large-scale stru cture measurements\, which go beyond the most common 2x3pt shear and galax y clustering measurements for cosmology. Firstly\, I will discuss newly di scovered cross-correlations between gravitational shear and flexion\, incl uding their surprising anticommutative properties. Secondly\, I will discu ss our latest understanding of cross-correlations between lensing and radi o intensity mapping\, which do not vanish due to foreground removal as mig ht be supposed. Finally\, I will discuss the latest higher order statistic s LSS techniques and results in current cosmological surveys.\n\nhttps://p artphys-indico.unige.ch/event/1441/contributions/9935/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9935/ END:VEVENT BEGIN:VEVENT SUMMARY:Relativistic effects down to non-linear scales: insights from the RayGal simulations DTSTART;VALUE=DATE-TIME:20240712T070000Z DTEND;VALUE=DATE-TIME:20240712T073000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9929@partphys-indico.unige.ch DESCRIPTION:Speakers: Yann RASERA (LUTH/Université Paris Cité/Observatoi re de Paris/IUF)\nIn this talk\, I would like to highlight some key result s from our RayGal studies of the impact of general relativistic effects on the apparent distribution of large-scale structures down to non-linear sc ales. We have investigated the dipole of the halo-halo cross-correlation from the 150 Mpc/h scale to the 5 Mpc/h scale. At large scales\, we recove r the linear expectation while at scales smaller than 30-60 Mpc/h the grav itational redshift contribution dominates together with non-trivial coupli ngs. We have also investigated the impact of the magnification bias on the 3x2pts cross-correlation between gravitational convergence and the matter density field. At linear and quasi-linear scales\, we recover Class analy tical results while at smaller scales interesting deviations and effects a ppear (lensing bias\, Finger-of-God effects\, non-trivial couplings). I wo uld be happy to discuss with workshop participants about new relativistic observables in the non-linear regime of structure formation.\n\nhttps://pa rtphys-indico.unige.ch/event/1441/contributions/9929/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9929/ END:VEVENT BEGIN:VEVENT SUMMARY:How to measure lensing rotation DTSTART;VALUE=DATE-TIME:20240711T130000Z DTEND;VALUE=DATE-TIME:20240711T133000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9924@partphys-indico.unige.ch DESCRIPTION:Speakers: Antony Lewis (University of Sussex)\nFirst-order gra vitational lensing is a pure gradient\, and hence only gives image magnifi cation and shear. But post-Born corrections give rise to an additional sma ll image rotation. I discuss the impact of this rotation on galaxies and the CMB temperature and polarization\, and explain the challenges in tryin g to measure it. The rotation is somewhat enhanced for CMB lensing due to the large source path length\, but remains small and very challenging to detect directly by CMB lensing reconstruction alone. I show the rotation m ay be detectable at high significance as a cross-correlation signal betwee n the curl reconstructed with Simons Observatory (SO) or CMB-S4 data\, and a template constructed from quadratic combinations of large-scale structu re (LSS) tracers. I’ll give forecasts showing that in idealized cases th is should be a new signal detectable at over 5 sigma with forthcoming data \, and describe some of the theoretical complications. There is a follow-u p talk by Mathew Robertson discussing more realistic cases and simulation results.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9924 / LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9924/ END:VEVENT BEGIN:VEVENT SUMMARY:Spherical bispectrum expansion and quadratic estimators DTSTART;VALUE=DATE-TIME:20240711T123000Z DTEND;VALUE=DATE-TIME:20240711T130000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9887@partphys-indico.unige.ch DESCRIPTION:Speakers: Julien Carron ()\nQuadratic estimators (used notably for current most precise CMB lensing measurements) are a wide class of es timators efficient in capturing small signals of anisotropies. They will p rovide sub-percent contraints on the growth structure in the near future. After discussing how these estimators relate to bispectra\, I will descri be a general expansion of spherical (full-sky) bispectra into a set of ort hogonal modes\, with the aim to separate physically-distinct signals. The expansion uses a new set of discrete polynomials that are pairwise orthog onal with respect to the relevant Wigner 3j symbol\, and reduce as desired to Chebyshev polynomials (i.e. Fourier series) in the flat-sky limit for both parity-even and parity-odd cases. We use the full-sky expansion to co nstruct a tower of orthogonal CMB lensing quadratic estimators and constru ct estimators that are immune to foregrounds like point sources or noise i nhomogeneities. In parity-even combinations (such as the lensing gradient mode from TT\, or the lensing curl mode from EB) the leading two modes can be identified with information from the magnification and shear respectiv ely\, whereas the parity-odd combinations are shear-only.\n\nhttps://partp hys-indico.unige.ch/event/1441/contributions/9887/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9887/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmological Geometry and Gravity with non-linear clustering DTSTART;VALUE=DATE-TIME:20240711T073000Z DTEND;VALUE=DATE-TIME:20240711T080000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9888@partphys-indico.unige.ch DESCRIPTION:Speakers: Luca Amendola (University Heidelberg)\nA new avenue was recently developed for analyzing large-scale structure data with a mod el-independent approach\, in which the linear power spectrum shape is para metrized with a large number of freely varying wavebands rather than by as suming specific cosmological models. Here we show\, using a Fisher matrix approach\, that the precision of this method for the case of the one-loop power spectrum is greatly improved with the inclusion of the tree-level bi spectrum. We also show that accuracy can be similarly improved by employin g perturbation theory kernels whose structure is entirely determined by sy mmetries instead of evolution equations valid in particular models (like i n the usual Einstein-de Sitter approximation). We also present preliminary results of an application to real data from the BOSS survey. Finally\, we show how these results can test cosmic geometry and gravity in a model-in dependent way.\n\nhttps://partphys-indico.unige.ch/event/1441/contribution s/9888/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9888/ END:VEVENT BEGIN:VEVENT SUMMARY:Monopole fluctuations in galaxy surveys DTSTART;VALUE=DATE-TIME:20240711T070000Z DTEND;VALUE=DATE-TIME:20240711T073000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9925@partphys-indico.unige.ch DESCRIPTION:Speakers: Jaiyul Yoo (University of Zurich)\nGalaxy clustering provides a powerful way to probe cosmology. This requires understanding o f the background mean density of galaxy samples\, which is estimated from the survey itself by averaging the observed galaxy number density over the angular position. The angle average includes not only the background mean density\, but also the monopole fluctuation at each redshift. Here for th e first time we compute the monopole fluctuations in galaxy surveys. The m onopole fluctuations vary as a function of redshift\, and it is correlated with other fluctuations\, affecting the two-point correlation function me asurements. The rms fluctuation at z = 0.5 can be as large as 7% of the tw o-point correlation function in amplitude at the BAO scale\, and it become s smaller than 1% at z > 2. The monopole fluctuations are unavoidable\, bu t they can be modeled. We discuss its relation to the integral constraint and the implications for the galaxy clustering analysis.\n\nhttps://partph ys-indico.unige.ch/event/1441/contributions/9925/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9925/ END:VEVENT BEGIN:VEVENT SUMMARY:High(ish)-redshift cosmology with the Quaia quasar catalog DTSTART;VALUE=DATE-TIME:20240711T080000Z DTEND;VALUE=DATE-TIME:20240711T083000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9926@partphys-indico.unige.ch DESCRIPTION:Speakers: David Alonso (University of Oxford)\nLarge-Scale Str ucture cosmology has made tremendous progress in the last few years\, and is now able to place constraints on cosmological parameters with a precisi on rivalling that achieved by CMB experiments. In this process\, the conco rdance Lambda CDM model has been shown to provide a very reasonable descri ption of the evolution of the Universe's structure and expansion at late t imes. However\, small cracks in the model have appeared\, in the form of m oderate tensions between parameters measured directly from low-redshift da ta and those inferred from the CMB. Elucidating the origin of these has be en a key task for the community in the last few years. However\, the evide nce for these tensions comes\, predominantly\, from data at fairly low red shifts (distance ladder\, cosmic shear). The intermediate-redshift univers e (1\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9926/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9926/ END:VEVENT BEGIN:VEVENT SUMMARY:The ESA Euclid mission: status and outlook DTSTART;VALUE=DATE-TIME:20240710T120000Z DTEND;VALUE=DATE-TIME:20240710T123000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9889@partphys-indico.unige.ch DESCRIPTION:Speakers: Martin Kunz ()\nIn my presentation I will start with an overview of the Euclid satellite\, discuss its current status and show some recent early results. I will then give a brief outlook of the expect ed science results in the coming years.\n\nhttps://partphys-indico.unige.c h/event/1441/contributions/9889/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9889/ END:VEVENT BEGIN:VEVENT SUMMARY:Toward Robust Measurements of Relativistic Effects in Galaxy Clust ering with DESI and Euclid DTSTART;VALUE=DATE-TIME:20240710T130000Z DTEND;VALUE=DATE-TIME:20240710T133000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9930@partphys-indico.unige.ch DESCRIPTION:Speakers: Francesca Lepori (University of Zurich)\nGravitation al redshift and Doppler effects give rise to an antisymmetric component of the galaxy correlation function when cross-correlating two galaxy populat ions or different tracers. Relativistic effects can be isolated from densi ty and redshift space distortions (RSDs) clustering signals by splitting t he galaxy population into two catalogs and using adapted estimators\, such as the dipole of the cross-correlation function. Spectroscopic galaxy sur veys\, specifically the Dark Energy Spectroscopic Instrument (DESI) at low redshift and Euclid at higher redshift\, will allow us to extract the sig nal with high significance across a wide range of scales. In this talk\, I will discuss the prospects of measuring this observable in the near futur e. I will present forecasts for DESI and Euclid based on N-body simulation s and discuss the potential challenges in modelling this signal on large a nd small scales.\n\nhttps://partphys-indico.unige.ch/event/1441/contributi ons/9930/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9930/ END:VEVENT BEGIN:VEVENT SUMMARY:Covariant Cosmography with the Expansion Rate Fluctuations Field DTSTART;VALUE=DATE-TIME:20240710T080000Z DTEND;VALUE=DATE-TIME:20240710T083000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9891@partphys-indico.unige.ch DESCRIPTION:Speakers: Christian Marinoni (Centre de Physique Théorique\, Aix-Marseille Univ.)\nIs it possible to construct a detailed model of loca l spacetime in a completely model-independent and non-perturbative manner? Specifically\, this would involve developing an observationally viable an d physically meaningful method for identifying and classifying angular dis tortions present in the distance-redshift relation\, without relying on th e cosmological principle or the notion of peculiar velocities. The first d ifficulty along this path is the meaningful generalization of the notion o f the cosmic expansion rate at an arbitrary point P in a generic spacetim e. This involves defining covariant cosmographic parameters\, which are a set of line-of-sight dependent functions\, with finite degrees of freedom\ , characterizing deviations from isotropy and critically dependent on the observer's state of motion. The second challenge revolves around the opti mal estimation of anisotropies in the expansion rate using observational d ata. To this end\, we define the expansion rate fluctuation field η\, an observable designed to maximize measurement accuracy while minimizing pote ntial biases. \nUsing analytical models\, we analyze the virtues and limit ations of this formalism. Current results and future survey prospects for constraining the shape of the expansion rate field in the local universe w ill also be presented.\n\nhttps://partphys-indico.unige.ch/event/1441/cont ributions/9891/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9891/ END:VEVENT BEGIN:VEVENT SUMMARY:First measurement of the Weyl potential evolution from DES Y3 data DTSTART;VALUE=DATE-TIME:20240709T123000Z DTEND;VALUE=DATE-TIME:20240709T130000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9934@partphys-indico.unige.ch DESCRIPTION:Speakers: Isaac Tutusaus (IRAP-OMP)\nIn this talk I will prese nt a new methodology to measure the Weyl potential\, which is the sum of t he spatial and temporal distortions of the Universe's geometry\, in a mode l independent way. I will then present how combining galaxy clustering and galaxy-galaxy lensing data from the Dark Energy Survey Year 3 measurement s we can provide the first direct measurement of the evolution of the Weyl potential at four different redshifts. I will end by showing the forecast precision of such measurements with stage IV surveys.\n\nhttps://partphys -indico.unige.ch/event/1441/contributions/9934/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9934/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmic shear with Einstein rings DTSTART;VALUE=DATE-TIME:20240709T130000Z DTEND;VALUE=DATE-TIME:20240709T133000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9900@partphys-indico.unige.ch DESCRIPTION:Speakers: Julien Larena (Université de Montpellier/ LUPM)\nMa ssive galaxies\, acting as gravitational lenses\, can form greatly distort ed images of background galaxies in so called strong lensing events. When background galaxy and lens are almost aligned along the line of sight\, th e image take the shape of an Einstein ring whose shape encodes basic prope rties of the lens. However\, since lenses are not isolated objects in an o therwise perfectly homogeneous universe\, these Einstein rings are sligthl y altered by further weak lensing along the line of sight coming from the large scale matter distribution in the universe in front and behind the le ns. This coupling between strong and weak lensing offers a novel opportuni ty to probe cosmic shear\, in a regime that is not plagued by the same sys tematics as standard weak lensing shear. We will present this new method a nd its perspectives for the Euclid survey.\n\nhttps://partphys-indico.unig e.ch/event/1441/contributions/9900/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9900/ END:VEVENT BEGIN:VEVENT SUMMARY:Novel biases in standard weak lensing and galaxy clustering analys es DTSTART;VALUE=DATE-TIME:20240709T120000Z DTEND;VALUE=DATE-TIME:20240709T123000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9927@partphys-indico.unige.ch DESCRIPTION:Speakers: Alex Hall (University of Edinburgh)\nForthcoming wea k lensing and galaxy clustering surveys\, such as Euclid and LSST\, offer unprecedented statistical precision. If new physics is to be discovered fr om these data sets\, standard analysis methods that have previously suffic ed must be carefully scrutinised. I will present recent calculations of se veral subtle biases that arise from neglecting non-linearity in the underl ying density field and sub-optimal measurement choices. I will discuss how these effects might impact attempts to measure relativistic effects on la rge scales. Finally\, I will look ahead to Euclid DR1\, a rich data set fo r the community due for public release in 2026.\n\nhttps://partphys-indico .unige.ch/event/1441/contributions/9927/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9927/ END:VEVENT BEGIN:VEVENT SUMMARY:Gravitational Redshift of Galaxies in Clusters DTSTART;VALUE=DATE-TIME:20240709T074000Z DTEND;VALUE=DATE-TIME:20240709T081000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9933@partphys-indico.unige.ch DESCRIPTION:Speakers: Ofer Lahav ()\nhttps://partphys-indico.unige.ch/even t/1441/contributions/9933/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9933/ END:VEVENT BEGIN:VEVENT SUMMARY:Testing General Relativity with cosmological large scale structure observations DTSTART;VALUE=DATE-TIME:20240709T071000Z DTEND;VALUE=DATE-TIME:20240709T074000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9899@partphys-indico.unige.ch DESCRIPTION:Speakers: Ruth Durrer (Département de physique théorique\, U niversité de Genève)\nGeneral relativity has been tested in the solar sy stem and with other astrophysical observations and passed all tests with f lying colours. However\, these were essentially tests of the vacuum Einste in equations. Cosmology is different. Not only do we test GR on much large r scales\, but it is also a very essential non-vacuum solution of the theo ry.\nObserving LSS we cannot only measure the density distribution and vel ocities\, but\, when considering relativistic effects\, we can also measur e the metric. In my talk I shall present a few examples on how LSS observ ations can provide tests of General Relativity.\n\nhttps://partphys-indico .unige.ch/event/1441/contributions/9899/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9899/ END:VEVENT BEGIN:VEVENT SUMMARY:What makes a filament? DTSTART;VALUE=DATE-TIME:20240712T090000Z DTEND;VALUE=DATE-TIME:20240712T091500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9750@partphys-indico.unige.ch DESCRIPTION:Speakers: Job Feldbrugge (University of Edinburgh)\nThe cosmic web is the largest geometric structure in our universe\, consisting of an intricate network of empty voids bounded by thin walls\, elongated filame nts\, and dense clusters. Given the array of upcoming cosmological redshif t surveys\, new analytic tools are needed to study the formation of the va rious structures\, quantify the geometry and topology\, and isolate the el ements of the cosmic web. New techniques might\, for example\, help to und erstand the link between the properties of galaxies and their placement in the large-scale structure. In this talk\, I will present my recent develo pments in the study of the caustic skeleton of the cosmic web. By tracing the phase-space structure of the dark matter sheet\, I identify the releva nt caustics and illustrate their role in the cosmic web. I will propose a new definition of the filamentary structure of the large-scale structure i n terms of the initial density fluctuations. This definition is based on t he dynamics of the formation history and will help the systematic study of the properties and interplay of filaments\, and their influence on the em bedded galaxies.\n\nhttps://partphys-indico.unige.ch/event/1441/contributi ons/9750/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9750/ END:VEVENT BEGIN:VEVENT SUMMARY:Light propagation through discrete dark matter and its relativisti c effects DTSTART;VALUE=DATE-TIME:20240712T094500Z DTEND;VALUE=DATE-TIME:20240712T100000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9760@partphys-indico.unige.ch DESCRIPTION:Speakers: Annamalai P. Shanmugaraj (CP3-Origins\, University o f Southern Denmark)\nLight propagation in cosmology is usually studied in the geometrical optics approximation which requires the spacetime curvatur e to be much smaller than the light wavenumber. However\, for non-fuzzy pa rticle dark matter the curvature is concentrated in widely separated spike s at particle location. We consider a post-geometrical optics approximatio n that includes curvature and solve the Maxwell's equation in curved space time. We model the dark matter particle as interior Schwarzschild metric a nd propagate a plane light wave through it. For this\, we numerically evol ve (using the Einstein Toolkit framework) the Maxwell's equation in curved spacetime. Here\, we expect to observe photons gaining a gravity-induced mass when travelling through dark matter\, and light paths are not null no r geodesic.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9 760/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9760/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmic Voids as Powerful Probe in Next-Generation Surveys DTSTART;VALUE=DATE-TIME:20240712T091500Z DTEND;VALUE=DATE-TIME:20240712T093000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9767@partphys-indico.unige.ch DESCRIPTION:Speakers: Giovanni Verza (NYU)\nIn recent years\, cosmic voids have emerged as a promising new tool in cosmology\, offering valuable ins ights complementary to galaxy 2-point statistics. However\, to effectively utilize voids as cosmological probes to analyze the huge amount of data e xpected from upcoming surveys\, robust statistical modeling is imperative. In this presentation\, we introduce a novel combination of the excursion- set approach with peak theory formalism\, providing accurate predictions f or both halo and void statistics across a broad spectrum of scales. Specif ically\, we show that our theoretical framework yields halo mass functions and void size functions that closely match measurements obtained from sim ulations. Furthermore\, we derive Lagrangian void density profiles that ac curately match observations from cosmological simulations. Finally\, we ex plore the potential of voids in precision cosmology within the context of upcoming galaxy surveys\, such as Euclid and Roman\, discussing their comp lementarity in probing dark energy density\, equation of state\, and massi ve neutrinos alongside other cosmological probes.\n\nhttps://partphys-indi co.unige.ch/event/1441/contributions/9767/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9767/ END:VEVENT BEGIN:VEVENT SUMMARY:Gravitational collapse\, cosmic web and (almost) spherical cows DTSTART;VALUE=DATE-TIME:20240712T093000Z DTEND;VALUE=DATE-TIME:20240712T094500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9775@partphys-indico.unige.ch DESCRIPTION:Speakers: Leonardo Giani (The University of Queensland)\nDespi te more than a decade of effort\, we still need to understand why our infe rence of cosmological parameters from early and late time Universe probes\ , most notably the value of the Hubble constant\, differ. One of the reaso ns might be that the Universe\, despite being homogeneous and isotropic on very large scales\, is highly inhomogeneous at smaller ones\, where we li ve and perform our measurements. In this talk\, I will review the analytic al tools employed to describe the evolution of the cosmic web\, from the t iny fluctuations imprinted in the cosmic microwave background to the compl ex structures we observe today in the sky.\nI'll focus on our understandin g of the non-linear gravitational collapse based on a few simplifying assu mptions\, the most critical being spherical symmetry. I will show a recent ly proposed generalisation of the spherical collapse to an arbitrary aniso tropic shape (described by the Bianchi IX geometry) and its impact on larg e-scale-structure physics. The emerging picture is one of a homogeneous Un iverse composed of almost spherical cows. We speculate on their collective behaviour and discuss how one of them\, Laniakea\, might bias our cosmolo gical inference.\n\nhttps://partphys-indico.unige.ch/event/1441/contributi ons/9775/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9775/ END:VEVENT BEGIN:VEVENT SUMMARY:21cm IM with HIRAX: Simulation and Parameter Estimation DTSTART;VALUE=DATE-TIME:20240712T100000Z DTEND;VALUE=DATE-TIME:20240712T101500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9799@partphys-indico.unige.ch DESCRIPTION:Speakers: Viraj Nistane (Université de Genève)\nThe *Hydroge n Intensity and Real-time Analysis eXperiment* (HIRAX) is a radio interfer ometer array currently in development\, with an initial 256-element array to be deployed at the SARAO *Square Kilometer Array* (SKA) site in South A frica. Through 21cm Intensity Mapping\, HIRAX will provide a cosmological survey of the distribution of the large-scale structure over the redshift range of $ 0.775 \n\nhttps://partphys-indico.unige.ch/event/1441/contribut ions/9799/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9799/ END:VEVENT BEGIN:VEVENT SUMMARY:Novel Bayesian Inferences from the Cosmic Microwave Background DTSTART;VALUE=DATE-TIME:20240711T143000Z DTEND;VALUE=DATE-TIME:20240711T144500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9761@partphys-indico.unige.ch DESCRIPTION:Speakers: Sayan Saha (Indian Institute of Science Education an d Research (IISER)\, Dr. Homi Bhabha Road\, Pune 411008\, India)\nIn the e volving landscape of modern precision cosmology\, the continuous progress of ongoing and upcoming surveys has provided us an unprecedented level of statistical power. Throughout my doctoral journey\, I have mostly explored the Cosmic Microwave Background (CMB) at small angular scales\, seeking t o constrain cosmological parameters. My research has been dedicated to the development of robust and optimal estimators\, poised to play a crucial r ole in current and future CMB surveys. In the first part\, I will discuss how the motion of our observation frame impacts CMB fluctuations\, specifi cally through aberration and modulation effects. These subtle effects at t he smaller scales\, violate the statistically isotropic nature of the CMB\ , and can be captured in the off-diagonal terms of the CMB covariance matr ix in harmonic space. In a Bayesian approach\, we have estimated our obser vation frame's motion from the Planck-2018 temperature data employing the Hamiltonian Monte Carlo (HMC) sampling technique. In the second part\, I w ill explore the utilization of the CMB in probing galaxy clusters\, which are the largest collapsed structures in the universe. What we are really c urious about is figuring out how many of these clusters exist at different masses and ages (redshifts). But measuring their mass is not straightforw ard. So\, we use the weak gravitational lensing of CMB to estimate how mas sive these clusters really are. In this talk\, I present the power of the Maximum-a-posteriori (MAP) method\, showcasing its enhanced precision in m easuring cluster masses compared to traditional quadratic estimators (QE)\ , for the upcoming CMB-Stage 4 experiment.\n\nhttps://partphys-indico.unig e.ch/event/1441/contributions/9761/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9761/ END:VEVENT BEGIN:VEVENT SUMMARY:CMB curl lensing DTSTART;VALUE=DATE-TIME:20240711T140000Z DTEND;VALUE=DATE-TIME:20240711T141500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9786@partphys-indico.unige.ch DESCRIPTION:Speakers: Mathew Robertson (University of Sussex)\nLensing rot ation (or curl lensing or shear B-modes) vanish at leading order in a conc ordance cosmology. However\, it can be produced from sequential lensing ev ents and is therefore a unique post-Born lensing observable. This rotation forms bispectra with other large-scale structure tracers\, which can be l everaged to optimally probe the rotation as a cross-spectrum signal. I des cribe this process for the CMB lensing case\, and with the aid of external tracers I will forecast the detection prospects for upcoming CMB experime nts the Simons Observatory (SO) and CMB-S4. I also derive an equivalent cu rl estimator for the curved-sky\, and present detailed validation of the m ethods using mock data from N-body simulations. This will include sensitiv ities to non-Gaussianities\, state-of-the-art iterative lensing estimators \, and robustness against extra-galactic foregrounds. I wrap up with some cosmology forecasts that would accompany a CMB curl detection.\n\nhttps:// partphys-indico.unige.ch/event/1441/contributions/9786/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9786/ END:VEVENT BEGIN:VEVENT SUMMARY:Testing Gravity with cross-correlations of CMB and LSS DTSTART;VALUE=DATE-TIME:20240711T141500Z DTEND;VALUE=DATE-TIME:20240711T143000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9787@partphys-indico.unige.ch DESCRIPTION:Speakers: Guglielmo Frittoli (Università Roma La Sapienza)\nT he accelerated expansion of the Universe is canonically attributed to the Dark Energy (DE)\, encapsulated in the Lambda factor in the Einstein field equations of gravity\, but its nature is still not understood. While obse rvations supply strong evidence in favor of the standard model of cosmolog y Lambda-CDM\, a plethora of different modified gravity models (MG) can st ill arise and describe gravity and DE in another way than a Lambda-constan t. In our work\, we exploit the Effective Field Theory (EFT) framework whi ch allows us to describe gravity and DE in a general way\, encompassing si ngle-field models. The strength of this approach is that we can describe n ot only general features of gravity but also recover model-dependent resul ts through a mapping procedure. Upon this theoretical setting\, we combine CMB and galaxy-clustering observables to discriminate between Lambda-CDM and MG/DE models. One of our main aims is to specifically assess the const raining power of cross-correlations between different probes from wide gal axy surveys\, like Euclid\, and the high sensitivity maps of the microwave sky delivered by Planck.\n\nhttps://partphys-indico.unige.ch/event/1441/c ontributions/9787/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9787/ END:VEVENT BEGIN:VEVENT SUMMARY:Cross-correlations with gravitational waves in luminosity distance space DTSTART;VALUE=DATE-TIME:20240711T101500Z DTEND;VALUE=DATE-TIME:20240711T103000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9755@partphys-indico.unige.ch DESCRIPTION:Speakers: Stefano Zazzera (Queen Mary University of London)\nT hird generation gravitational waves (GWs) observatories such as Einstein T elescope and Cosmic Explorer will yield an abundance of extra-galactic tra nsient objects. Cross-correlations using GW merger events offer novel and powerful insights into the large-scale distribution of matter in the univ erse. These sources carry information on their luminosity distance\, but r emain uninformative about their redshifts\; hence their clustering analyse s and cross-correlations need to be carried out in luminosity distance spa ce\, as opposed to redshift space. Further\, the large volumes accessible to these surveys imply that we may need to include relativistic correction s\, such as lensing and Doppler magnification. However\, the amplitude of these effects depends on the magnification and evolution biases of the tra nsient sources\, which are not yet understood. In this talk\, I present a comparison of the number count angular power spectra between luminosity di stance and redshift spaces\, highlighting the inaccuracy of GWs clustering analysis when carried out in a different space\, particularly at larger s cales. Then\, we employ Fisher forecasts to constrain the clustering\, mag nification and evolution biases of GWs from binary black hole (BBH) merger s in luminosity distance space\, accounting for all relativistic effects. Constraining the bias parameters effectively implies constraining properti es of the BBH population responsible for GWs emissions\, thus potentially inferring both their redshift and mass distributions.\n\nhttps://partphys- indico.unige.ch/event/1441/contributions/9755/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9755/ END:VEVENT BEGIN:VEVENT SUMMARY:Non-Gaussianities in the Hubble-Lemaitre diagram DTSTART;VALUE=DATE-TIME:20240711T100000Z DTEND;VALUE=DATE-TIME:20240711T101500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9757@partphys-indico.unige.ch DESCRIPTION:Speakers: Tiziano Schiavone (Galileo Galilei Institute for The oretical Physics)\nLocal effects in a clumpy Universe affect photon paths and give rise to non-Gaussian features in the large-scale structure. We ev aluate the higher-order moments for the distribution of the luminosity dis tance by adopting the averaging formalism on the past light cone. We compu te the skewness in the Hubble-Lemaître diagram at the leading order in th e cosmological perturbative expansion of the gravitational potential. In p articular\, we focus on perturbations of the luminosity distance due to gr avitational lensing. We discuss our findings in view of recent numerical r elativistic simulations\, confirming that the skewness of the distance-red shift relation primarily originates from the late-time matter bispectrum a s a signature of the interplay between photons and cosmic structures.\n\nh ttps://partphys-indico.unige.ch/event/1441/contributions/9757/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9757/ END:VEVENT BEGIN:VEVENT SUMMARY:Testing gravity through the distortion of time DTSTART;VALUE=DATE-TIME:20240711T091500Z DTEND;VALUE=DATE-TIME:20240711T093000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9764@partphys-indico.unige.ch DESCRIPTION:Speakers: Sveva Castello (University of Geneva)\nThe distribut ion of galaxies provides an ideal laboratory to test deviations from Gener al Relativity. In particular\, constraints on gravity modifications are co mmonly obtained by measuring the growth of cosmic structures through redsh ift-space distortions. However\, such constraints rely on the validity of the weak equivalence principle\, which has never been tested for the dark matter component. In my talk\, I will show that dropping this restrictive assumption leads to severe degeneracies and makes it challenging to distin guish fundamental gravity modifications from interactions in the dark sect or. Luckily\, I will demonstrate that it is possible to break such degener acies and recover tight constraints thanks to measurements of the distorti on of time expected from upcoming galaxy surveys.\n\nhttps://partphys-indi co.unige.ch/event/1441/contributions/9764/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9764/ END:VEVENT BEGIN:VEVENT SUMMARY:Infrared-safe cosmological probes in any gravity theory DTSTART;VALUE=DATE-TIME:20240711T090000Z DTEND;VALUE=DATE-TIME:20240711T091500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9779@partphys-indico.unige.ch DESCRIPTION:Speakers: Matteo Magi ()\nA distinctive feature of relativisti c effects in the cosmological probes is the presence of terms that scale w ith negative powers of $k$ relative to the matter density fluctuations. Pe rturbative calculations in $\\Lambda$CDM have shown that the infrared dive rgences that these terms could in principle cause are cancelled out\, in a greement with the equivalence principle.\nIn this talk\, I will show that it is possible to derive a simple set of general conditions that control t he infrared sensitivity of cosmological probes by working at linear order in relativistic perturbation theory and without assuming any gravity theor y. Given the simplicity of our general conditions\, I will show that it is possible to recover the $\\Lambda$CDM cancellations mentioned above witho ut performing any calculations. Finally\, I will comment on the possibilit y of applying these conditions to gravity theories other than general rela tivity.\nThe importance of this work lies in the clear identification of t he physical reasons that underlie the infrared sensitivity of the cosmolog ical probes.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/ 9779/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9779/ END:VEVENT BEGIN:VEVENT SUMMARY:Detecting Relativistic Doppler in Galaxy Clustering via Multi-trac ing a Single Galaxy Population DTSTART;VALUE=DATE-TIME:20240710T143000Z DTEND;VALUE=DATE-TIME:20240710T144500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9763@partphys-indico.unige.ch DESCRIPTION:Speakers: Federico Montano (University of Turin)\nThe descript ion of gravity\, i.e. the theory of general relativity\, plays a crucial r ole in our understanding of the universe. However\, confirmations of the v alidity of this theory on cosmological scales have hitherto eluded us. In this context\, the detection of relativistic Doppler via galaxy power spec trum measurements could further confirm the validity of general relativity at scales very far from the strong-gravity-field regime\, where instead i t has been tested with exquisite accuracy. The Doppler term acts as an ima ginary correction in the relation between the galaxy density contrast and that of matter\, which mostly affects the large-scales usually plagued by cosmic variance. Cross-correlation power spectra seem to be much more prom ising than auto-correlation ones\, due to the presence of the relativistic effect in a non-vanishing imaginary term that might be relevant even at i ntermediate scales. Moreover\, relativistic Doppler is sample-dependent\, so different galaxy populations display different contributions in their p ower spectra. In the search for the optimal galaxy samples to achieve a de tection of the relativistic term\, we can split a galaxy population accord ing to luminosity\, and even perform a multi-tracer analysis with auto-cor relations of the two sub-samples and their cross-power spectrum. We are th us able to devise a technique enjoying multi-tracer benefits out of a sing le dataset and obtain a detection well above 5σ.\n\nhttps://partphys-indi co.unige.ch/event/1441/contributions/9763/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9763/ END:VEVENT BEGIN:VEVENT SUMMARY:Unequal Time Effects in Large Scale Structure Correlators DTSTART;VALUE=DATE-TIME:20240710T150000Z DTEND;VALUE=DATE-TIME:20240710T151500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9770@partphys-indico.unige.ch DESCRIPTION:Speakers: Theo Steele (University of Sussex)\nLarge scale stru cture correlators will be one of the most important probes of fundamental physics in the years to come. The results of redshift surveys which are u sed to measure these correlators sort their results into redshift bins for convenient analysis. In this short talk\, we will discuss the implementa tion of corrections to account for differences in redshift between observa bles in the context of what we call field and spectrum level projections\, which are built upon Fourier transforming expansions around assumed redsh ifts and deriving correlators from the ensuing fields.\n\nhttps://partphys -indico.unige.ch/event/1441/contributions/9770/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9770/ END:VEVENT BEGIN:VEVENT SUMMARY:Accurate modeling of 3D large-scale galaxy clustering DTSTART;VALUE=DATE-TIME:20240710T144500Z DTEND;VALUE=DATE-TIME:20240710T150000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9772@partphys-indico.unige.ch DESCRIPTION:Speakers: Alvise Raccanelli (University of Padova)\nFuture sur veys will measure galaxy clustering on unexplored regimes and with better than ever precision.\nIn my talk I will discuss some investigations on how this precision will be wasted if not matched by a comparable level of acc uracy.\nI will present the recent developement of a formalism for includin g radial modes information and new observables based on it.\nFurthermore\, I will show studies quantifying the mis-estimation of cosmological parame ters when taking approximations that were acceptable until now but will no t be for future surveys.\nFinally\, I will present a new proposal for a ga laxy survey measuring the clustering at very high redshift.\n\nhttps://par tphys-indico.unige.ch/event/1441/contributions/9772/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9772/ END:VEVENT BEGIN:VEVENT SUMMARY:Complex Evaluation of Angular Power Spectra - Case Study DTSTART;VALUE=DATE-TIME:20240710T153000Z DTEND;VALUE=DATE-TIME:20240710T154500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9773@partphys-indico.unige.ch DESCRIPTION:Speakers: Benjamin Hertzsch (University of Edinburgh)\nThe ang ular power spectrum is a key observable for upcoming high-precision cosmol ogical surveys. However\, modelling them typically involves the numerical evaluation of highly oscillatory 3-dimensional integrals that are computat ionally expensive using brute-force methods. In recent years\, there has b een increased interest in numerical methods that go beyond the well-known Limber approximation to robustly calculate angular power spectra in a wide parameter regime. Building on Picard-Lefshetz theory\, we propose a new m ethod to evaluate the angular power spectrum in the complex plane. Using a saddle point approximation\, the computation is reduced to a one-dimensio nal integral\, resulting in a significant increase in computation speed. T his method elegantly complements the Limber approximation in the low-multi pole regime and can be straightforwardly extended to include general integ rands and redshift-space distortions. An application to typical survey ker nels is presented. A publicly available code is under development.\n\nhttp s://partphys-indico.unige.ch/event/1441/contributions/9773/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9773/ END:VEVENT BEGIN:VEVENT SUMMARY:Unequal-time corrections to the power spectrum DTSTART;VALUE=DATE-TIME:20240710T151500Z DTEND;VALUE=DATE-TIME:20240710T153000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9782@partphys-indico.unige.ch DESCRIPTION:Speakers: Eleonora Vanzan (University of Padova)\nUpcoming gal axy survey data will reach unprecedented precision\, which calls for a mat ching level of accuracy in the theoretical modeling of our observables. Re cently\, a novel formalism has been developed to account for unequal-time corrections in the two-point correlations\, when the two objects being cor related are not at the same redshift. In this talk\, for the first time\, I include general relativistic effects in the formalism and I provide an e stimate of the relevance of such corrections for future surveys.\n\nhttps: //partphys-indico.unige.ch/event/1441/contributions/9782/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9782/ END:VEVENT BEGIN:VEVENT SUMMARY:Simulating HI galaxies with Semi-Analytical Models in preparation for the SKAO late-time cosmology case DTSTART;VALUE=DATE-TIME:20240710T154500Z DTEND;VALUE=DATE-TIME:20240710T160000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9788@partphys-indico.unige.ch DESCRIPTION:Speakers: Joël Mayor (ETH Zürich)\nWith the advent of next-g eneration radio observations\, HI Galaxy surveys will be able to probe the late-time Universe with unprecedented sensitivity\, offering the possibil ity to constraint cosmology in a complementary manner to standard spectros copic surveys.\nIn preparation for this innovative scientific case\, reali stic simulations of large-sky volumes with good resolution are needed. In this talk I will discuss Semi-analytical models (SAM) that combine the adv antages of relatively large box sizes and resolutions fine enough to resol ve galaxy substructures. In particular\, I will present a study of HI gala xies 21cm lines based on the state-of-the-art Galaxy Evolution and Assembl y (GAEA) SAM. We employ the characteristic double-peak feature of the 21cm lines to obtain predictions for the HI Tully Fisher relation and validate the simulation by comparing to observations and exploring systematic effe cts. These type of study are key for understanding the realistic constrain ing power of peculiar velocity surveys with the SKAO. I will thus conclude discussing the next challenges and the roadmap for the future.\n\nhttps:/ /partphys-indico.unige.ch/event/1441/contributions/9788/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9788/ END:VEVENT BEGIN:VEVENT SUMMARY:Parity violation in the observed galaxy trispectrum DTSTART;VALUE=DATE-TIME:20240710T094500Z DTEND;VALUE=DATE-TIME:20240710T100000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9756@partphys-indico.unige.ch DESCRIPTION:Speakers: Pritha Paul (Queen Mary University of London)\nRecen t measurements of the 4-point correlation function in large-scale galaxy s urveys have found apparent evidence of parity violation in the distributio n of galaxies. This cannot happen via dynamical gravitational effects in g eneral relativity. If such a violation arose from physics in the early Uni verse it could indicate important new physics beyond the standard model\, and would be at odds with most models of inflation. It is therefore now ti mely to consider the galaxy trispectrum in more detail. While the intrinsi c 4-point correlation function\, or equivalently the trispectrum\, its Fou rier counterpart\, is parity invariant\, the observed trispectrum must tak e redshift-space distortions into account. Although the standard Newtonian correction also respects parity invariance\, we show that sub-leading rel ativistic corrections do not. We demonstrate that these can be significant at intermediate linear scales and are dominant over the Newtonian parity- invariant part around the equality scale and above. Therefore when observi ng the galaxy 4-point correlation function\, we should expect to detect pa rity violation on large scales.\n\nhttps://partphys-indico.unige.ch/event/ 1441/contributions/9756/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9756/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards Classifying Our Universe with Neural Networks DTSTART;VALUE=DATE-TIME:20240710T101500Z DTEND;VALUE=DATE-TIME:20240710T103000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9759@partphys-indico.unige.ch DESCRIPTION:Speakers: Benjamin Bose (University of Edinburgh)\nIn this tal k\, I will discuss the possibility of inferring properties of our Universe using a suitably trained neural network classifier. These properties can range from the nature of the gravitational interaction\, to the energy con tent\, to the presence of relativistic phenomena at cosmological scales. I will also discuss the difficulties faced by this approach\, particularly in error modeling\, and the ongoing work to overcome these.\n\nhttps://par tphys-indico.unige.ch/event/1441/contributions/9759/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9759/ END:VEVENT BEGIN:VEVENT SUMMARY:Fast and spurious: determining our peculiar velocity with galaxy s urveys DTSTART;VALUE=DATE-TIME:20240710T093000Z DTEND;VALUE=DATE-TIME:20240710T094500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9766@partphys-indico.unige.ch DESCRIPTION:Speakers: Fabien Lacasa (ULB - Université Libre de Bruxelles) \nTo date\, the most precise measurement of the observer's peculiar veloci ty comes from the dipole in the Cosmic Microwave Background. This velocity also generates a dipole in the source number counts. However its amplitud e is unfortunately also sensitive to specific properties of the sources\, that are difficult to determine precisely. Current studies give dipoles we ll aligned with the CMB dipole\, but with a significantly larger amplitude . In this work\, we develop an alternative method to measure our velocity from source counts\, by using off-diagonal correlations between neighborin g spherical harmonic coefficients. We show that these correlations contain both a term sensitive to the source properties and another more pristine one directly given by the observer velocity. We explore the potential of a Euclid-like survey to measure this second contribution\, independently of the characteristics of the population of sources. We find that the method can reach a high enough sensitivity to decide the fate of the present "di pole tension"\, with a significance of up to 6 sigma. With conservative pr iors on the source properties\, we can even reach a precision of ~4%\, cor responding to a detection significance of 24 sigma.\n\nhttps://partphys-in dico.unige.ch/event/1441/contributions/9766/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9766/ END:VEVENT BEGIN:VEVENT SUMMARY:Pantheon+ and friends: an insight on peculiar velocities probes DTSTART;VALUE=DATE-TIME:20240710T091500Z DTEND;VALUE=DATE-TIME:20240710T093000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9780@partphys-indico.unige.ch DESCRIPTION:Speakers: Francesco Sorrenti (University of Geneva - Cosmology Group)\nPeculiar velocities surveys are going to play a key role in testi ng our knowledge about the nearby universe and our cosmological assumption s. In this talk I will review some recent fundings and analysis that have been developped concerning these novel observables\n\nhttps://partphys-ind ico.unige.ch/event/1441/contributions/9780/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9780/ END:VEVENT BEGIN:VEVENT SUMMARY:Examining Late-Time Anisotropy With Weak-Lensing B-Modes and Tomog raphy DTSTART;VALUE=DATE-TIME:20240710T100000Z DTEND;VALUE=DATE-TIME:20240710T101500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9789@partphys-indico.unige.ch DESCRIPTION:Speakers: James Adam (University of the Western Cape)\nOne of the cornerstones of the standard model of cosmology is the assumption that \, on large scales\, the Universe is homogeneous and isotropic. Some dark energy and modified gravity models\, however\, naturally lead to large-sca le anisotropies. Thus\, it is of great importance to test this broad assum ption. One possible method of probing these anisotropies involves the use of weak gravitational lensing. More specifically\, the imprints that these anisotropies would have on the weak shear of light beams on cosmological scales could be analysed in upcoming surveys like Euclid\, SKA\, and LSST. We outline how we applied the perturbative formalism developed by Pitrou et al. (arXiv:[1503.01125][1]\,[1503.01127][2]) in order to estimate the m agnitude of $B$-mode shear generated in the weak lensing signal by large-s cale\, late-time anisotropic expansion. We examine the possibility of usin g tomographic lensing in order to break the degeneracy between anisotropic expansion histories. Finally\, we investigate how coupling between non-li nearities and anisotropic expansion may affect observed $B$-mode power spe ctra.\n\n\n [1]: https://arxiv.org/abs/1503.01125\n [2]: https://arxiv.o rg/abs/1503.01127\n\nhttps://partphys-indico.unige.ch/event/1441/contribut ions/9789/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9789/ END:VEVENT BEGIN:VEVENT SUMMARY:Estimating covariant cosmographic parameters in the local universe DTSTART;VALUE=DATE-TIME:20240710T090000Z DTEND;VALUE=DATE-TIME:20240710T091500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9798@partphys-indico.unige.ch DESCRIPTION:Speakers: Basheer Kalbouneh (Aix-Marseille university/ CPT)\nW e present a comparative analysis of the fluctuation field in the expansion rate of the local universe ($z\n\nhttps://partphys-indico.unige.ch/event/ 1441/contributions/9798/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9798/ END:VEVENT BEGIN:VEVENT SUMMARY:Multipoles of the galaxy bispectrum on a relativistic light cone DTSTART;VALUE=DATE-TIME:20240709T141500Z DTEND;VALUE=DATE-TIME:20240709T143000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9758@partphys-indico.unige.ch DESCRIPTION:Speakers: Christopher Addis (Queen Mary University of London)\ nNew surveys of the large-scale structure will offer the chance to probe u p to the Hubble scale to with percentage level precision. Therefore\, in o rder to accurately infer information from these scales\, we must consider percentage level corrections to our theoretical corrections that affect ou r observables. These include contributions from Doppler-type relativistic projection effects as well as wide separation effects\, which are induced as we correlate points separated by large distances. In this talk we inves tigate these contributions to the bispectrum in some detail\, including bo th wide angle effects and\, for the first time\, radial redshift effects. We show how they are intrinsically dependent on the choice of line of sigh t\, and how we can make better choices of LOS to mitigate these effects. W e investigate how they mix with the relativistic corrections and are of th e same order\, appearing similarly in the odd and even multipoles and can add additional relativistic signal through their mixing which is typically ignored. Further\, if unaccounted for\, we show they can mimic local type $f_{NL} \\sim \\mathcal{O}(10)$ in the worst cases.\n\nhttps://partphys-i ndico.unige.ch/event/1441/contributions/9758/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9758/ END:VEVENT BEGIN:VEVENT SUMMARY:Relativistic dipole in galaxy-ellipticity correlations DTSTART;VALUE=DATE-TIME:20240709T151500Z DTEND;VALUE=DATE-TIME:20240709T153000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9762@partphys-indico.unige.ch DESCRIPTION:Speakers: Shohei Saga (Kobayashi-Maskawa Institute)\nWe invest igate the effects imprinted in a cross-correlation function between galaxy positions and intrinsic galaxy shapes (GI correlation). We present an ana lytical model of the GI correlation function\, from which we find that the relativistic effects induce non-vanishing odd multipole anisotropies.We t hen estimate the signal-to-noise ratio and show that the GI dipole induced by the relativistic effects is detectable in future large-volume galaxy s urveys.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9762/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9762/ END:VEVENT BEGIN:VEVENT SUMMARY:Amplitude and Importance of Relativistic Contributions to the Gala xy Bispectrum DTSTART;VALUE=DATE-TIME:20240709T143000Z DTEND;VALUE=DATE-TIME:20240709T144500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9765@partphys-indico.unige.ch DESCRIPTION:Speakers: Samantha Rossiter (Università degli Studi di Torino )\nUpcoming galaxy surveys aim to map the universe with unprecedented prec ision\, 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 differentiating various models of inflation. On the scales where local PNG is strongest\, Doppler and other relativistic effects beco me important and need to be included. In this work\, we investigate the de tectability of relativistic and local PNG contributions in the galaxy bisp ectrum. We compute the signal-to-noise ratio for the detection of the bisp ectrum including such effects. Furthermore\, we perform information matrix forecasts on the local PNG parameter fNL and on the parametrised amplitud es of the relativistic corrections. Finally\, we quantify the bias on fNL from neglecting relativistic effects. Our results show that detections of both first- and second-order relativistic effects are promising with forth coming spectroscopic survey specifications – and are largely unaffected by the uncertainty in fNL. Conversely\, we show for the first time that ne glecting relativistic corrections in the galaxy bispectrum can lead to alm ost 3σ bias on the detected value of fNL\, highlighting the importance of including relativistic effects in our modelling.\n\nhttps://partphys-indi co.unige.ch/event/1441/contributions/9765/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9765/ END:VEVENT BEGIN:VEVENT SUMMARY:Relativistic matter bispectrum of cosmic structures DTSTART;VALUE=DATE-TIME:20240709T144500Z DTEND;VALUE=DATE-TIME:20240709T150000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9777@partphys-indico.unige.ch DESCRIPTION:Speakers: Thomas Montandon (University of Montpellier)\nUpcomi ng surveys of cosmic structures will probe scales ranging from the nonline ar regime to scales close to the cosmological horizon. This opens up the p ossibility of probing the ΛCDM model\, as well as early universe scenario s with non-Gaussianity. Modeling the galaxy bispectrum is challenging\, as it involves general relativity\, radiation\, and large nonlinearities. In this talk\, I will present the latest developments we have achieved in th e numerical and theoretical modeling of the matter angular bispectrum on t he light cone\, including relativistic and radiation effects. This is a cr ucial step towards modeling the observable bispectra\, i.e.\, the galaxy n umber count bispectrum and the weak lensing bispectrum.\n\nhttps://partphy s-indico.unige.ch/event/1441/contributions/9777/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9777/ END:VEVENT BEGIN:VEVENT SUMMARY:Towards Rigorous Modeling of Counts-in-Cells Statistics DTSTART;VALUE=DATE-TIME:20240709T153000Z DTEND;VALUE=DATE-TIME:20240709T154500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9781@partphys-indico.unige.ch DESCRIPTION:Speakers: Anton Chudaykin (University of Geneva)\nWe study the simplest non-perturbative statistics -- the one-point probability distrib ution function (PDF) for the averaged matter density inside spherical cell s. The leading part to the PDF is defined by spherical collapse dynamics\, whereas the next-to-leading part comes from the integration over fluctuat ions around the saddle-point solution. The latter calculation receives siz able contributions from short modes and must be renormalized. We propose a new approach to renormalization by modeling the effective stress-energy t ensor for short perturbations. The model contains three free parameters. T wo of them are related to the counterterms in the one-loop matter power sp ectrum and bispectrum\, one more parameterizes their redshift dependence. This relation can be used to impose priors in fitting the model to the PDF data. We confront the model with the results of high-resolution N-body si mulations and find excellent agreement for cell radii $r_∗ ≥ 10\\\, {\ \rm Mpc/h}$ at all redshifts down to $z = 0$. \n\nAdditionally\, we explor e the sensitivity of the one-point PDF to the cosmological parameters. Our results suggest that our PDF model is sensitive to the value of $\\sigma_ 8$ at the sub-per cent level. Another promising direction is to model the counterterm parameters in the Effective Field Theory of Large Scale Struct ure. Our PDF model provides comparable or better constraints on the counte rterm coefficients than the correlation functions.\n\nThe talk is based on the published paper -- https://iopscience.iop.org/article/10.1088/1475-75 16/2023/08/079.\n\nhttps://partphys-indico.unige.ch/event/1441/contributio ns/9781/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9781/ END:VEVENT BEGIN:VEVENT SUMMARY:Relativistic effects and the streaming model DTSTART;VALUE=DATE-TIME:20240709T150000Z DTEND;VALUE=DATE-TIME:20240709T151500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9785@partphys-indico.unige.ch DESCRIPTION:Speakers: Lawrence Dam (University of Geneva)\nThere are sever al effects that distort the clustering of galaxies\, the largest of which being the well-known redshift-space distortion. In this talk I will discus s the more subtle effect of gravitational redshift. The impact of this non -kinematic effect in the auto-correlations is suppressed relative to RSD a nd is best probed in the odd multipoles of the cross-correlation function between distinct tracers. Here the dipole has emerged as the best prospect for detecting the gravitational redshift from large-scale structure. Rece nt work however has shown that the strongest detection will likely be from mildly nonlinear scales\, presenting a modelling challenge. To this end\, I will describe recent modelling efforts. In particular\, I will show how to generalise the workhorse model of the correlation function\, the so-ca lled streaming model\, to include in a compact way not only the gravitatio nal redshift but several other important effects (wide-angle effects\, evo lution effects\, nonlinearities\, magnification bias\, etc). Several insig hts related to computing correlations in redshift space will be discussed. \n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9785/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9785/ END:VEVENT BEGIN:VEVENT SUMMARY:Exact Modeling of Power Spectrum Multipole through Spherical Fouri er-Bessel Basis DTSTART;VALUE=DATE-TIME:20240709T101000Z DTEND;VALUE=DATE-TIME:20240709T102500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9769@partphys-indico.unige.ch DESCRIPTION:Speakers: Yunfei (Robin) Wen (California Institute of Technolo gy)\nThe three-dimensional galaxy power spectrum is a powerful probe of pr imordial non-Gaussianity and additional general relativistic effects\, whi ch become important on large scales. At the same time\, wide-angle (WA) ef fects due to differing lines-of-sight (LOS) on the curved sky also become important with large angular separation. In this talk\, we present a new w ay to non-perturbatively model WA and GR effects present in the commonly u sed power spectrum multipoles (PSM). We accurately model WA and GR effects using the spherical Fourier-Bessel (SFB) formalism\, before transforming the result into the PSM. Moreover\, for the first time\, we can compute th e analytical PSM Gaussian covariance on large scales\, exactly including W A-induced mode-couplings\, without resorting to any plane-parallel approxi mations.\n\nhttps://partphys-indico.unige.ch/event/1441/contributions/9769 / LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9769/ END:VEVENT BEGIN:VEVENT SUMMARY:Cosmological cartography - The full-sky Spherical Fourier-Bessel p ower spectrum in general relativity DTSTART;VALUE=DATE-TIME:20240709T102500Z DTEND;VALUE=DATE-TIME:20240709T104000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9890@partphys-indico.unige.ch DESCRIPTION:Speakers: Federico Semenzato (University of Padova)\nAs our ma ps of Large Scale Structure increase in scale and precision and larger vol umes are probed\, it is crucial to properly model the observable quantitie s to construct robust predictions and maximize the information extracted b y these new surveys. We present a full methodology for analyzing galaxy cl ustering on the lightcone with the 2-point correlation in the Spherical Fo urier-Bessel (SFB) formalism. SFB is a natural choice to account for all w ide-angle and relativistic (GR) effects\, allowing to efficiently extract information from large volume galaxy surveys. We extend previous studies using SFB by including all projection and GR effects\, and we develop an e fficient numerical implementation that does not rely on commonly (mis)used approximations and includes a full non-diagonal covariance. We investigat e the impact of neglecting GR corrections in cosmological parameter constr aints\, focusing on Primordial Non-Gaussianity and bias parameters. We als o present a novel prescription for multi-bin correlations that allow to si gnificantly boost the detectability of GR effects\, opening a new window o n general relativity testing.\n\nhttps://partphys-indico.unige.ch/event/14 41/contributions/9890/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9890/ END:VEVENT BEGIN:VEVENT SUMMARY:General relativistic effects in the Spherical Fourier Bessel power spectrum with SPHEREx DTSTART;VALUE=DATE-TIME:20240709T092500Z DTEND;VALUE=DATE-TIME:20240709T094000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9754@partphys-indico.unige.ch DESCRIPTION:Speakers: Henry Grasshorn Gebhardt (Caltech)\, Yunfei (Robin) Wen (California Institute of Technology)\nSPHEREx is a full-sky galaxy sur vey that will launch in early 2025. It will detect ~500 Million galaxies o ver a redshift range 0 to ~4 with spectro-photometric redshifts. SPHEREx i s designed to measure the scale-dependent galaxy bias due to primordial no n-Gaussianity on large scales. However\, general relativistic effects show a similar scale dependence in the power spectrum and are projected to hav e similar signal size as non-Gaussianity. Furthermore\, typical power spec trum estimators are afflicted by wide-angle effects stemming from the geom etry of the curved sky\, and these wide-angle effects interact with relati vistic effects. To avoid wide-angle effects\, we use the spherical Fourier Bessel basis that is the harmonic basis in spherical coordinates\, thus h aving a natural separation of angular and line-of-sight effects. This make s it the ideal basis for measuring large-scale perturbations and relativis tic effects. I will present how GR effects such as lensing magnification e nter the SFB power spectrum and how it affects the non-Gaussianity measure ment\, especially with an eye towards the SPHEREx mission.\n\nhttps://part phys-indico.unige.ch/event/1441/contributions/9754/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9754/ END:VEVENT BEGIN:VEVENT SUMMARY:The importance of accuracy in the modeling of large scale galaxy c lustering DTSTART;VALUE=DATE-TIME:20240709T095500Z DTEND;VALUE=DATE-TIME:20240709T101000Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9783@partphys-indico.unige.ch DESCRIPTION:Speakers: Francesco Spezzati (University of Padova)\nFuture ga laxy surveys will observe tens of million of sources over large fraction o f the sky and various cosmic epochs. Currently\, statistical analyses of g alaxy distributions and their clustering are performed employing simplifyi ng assumptions such as the flat sky and plane parallel ones. In order to o btain not only precise\, but accurate analyses for future datasets\, a mor e precise formalism will be required. In this talk I will show that a prop er 3D modeling of galaxy correlations is needed in order to avoid systemat ic errors when performing tests of cosmological models with future large s cale structure experiments.\n\nhttps://partphys-indico.unige.ch/event/1441 /contributions/9783/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9783/ END:VEVENT BEGIN:VEVENT SUMMARY:GaPSE.jl: a model for the Galaxy Power Spectrum Estimator DTSTART;VALUE=DATE-TIME:20240709T091000Z DTEND;VALUE=DATE-TIME:20240709T092500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9784@partphys-indico.unige.ch DESCRIPTION:Speakers: Matteo Foglieni (Leibniz Rechenzentrum)\nIn the next few years\, the upcoming large-scale structure surveys such as DESI\, Euc lid\, and particularly SPHEREx\, are expected to significantly enhance sen sitivity in detecting the signature of primordial local non-Gaussianities (PNG)\, through the scale-dependent bias on the large scale limit of the g alaxy power spectrum.\nHowever\, on such large scales\, this PNG could be confused with general relativistic (GR) effects arising from the full rela tivistic expressions of the galaxy number counts (GNC).\nFor this reason\, we developed an open-source code\, [GaPSE.jl](https://github.com/foglieni matteo/GaPSE.jl) [1]\, that computes efficiently and accurately the observ ed power spectrum including GR and wide-angle effects\, with any realistic survey geometry for single and multi tracers. In this talk\, I will prese nt the main features of GaPSE and its basic uses.\n\n[1] Foglieni\, Pantir i\, Di Dio\, Castorina\, _Large Scale Limit of the Observed Galaxy Power S pectrum_ (2023)\, Phys. Rev. Lett. 131\, 111201\, DOI: [10.1103/PhysRevLet t.131.111201](https://doi.org/10.1103/PhysRevLett.131.111201)\n\nhttps://p artphys-indico.unige.ch/event/1441/contributions/9784/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9784/ END:VEVENT BEGIN:VEVENT SUMMARY:A multi-tracer approach to constrain primordial non-Gaussianity: r adio-optical synergies and the analysis of MeerKAT data DTSTART;VALUE=DATE-TIME:20240709T140000Z DTEND;VALUE=DATE-TIME:20240709T141500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9778@partphys-indico.unige.ch DESCRIPTION:Speakers: Matilde Barberi Squarotti ()\nhttps://partphys-indic o.unige.ch/event/1441/contributions/9778/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9778/ END:VEVENT BEGIN:VEVENT SUMMARY:Wide-angle and Doppler corrections to the power spectrum DTSTART;VALUE=DATE-TIME:20240709T094000Z DTEND;VALUE=DATE-TIME:20240709T095500Z DTSTAMP;VALUE=DATE-TIME:20260713T023530Z UID:indico-contribution-1441-9753@partphys-indico.unige.ch DESCRIPTION:Speakers: SECLOKA LAZARE GUEDEZOUNME (DEPARTMENT OF PHYSICS & ASTRONOMY\, UNIVERSITY OF THE WESTERN CAPE\, SOUTH AFRICA)\nThe distortion s in the galaxy number count introduced by perturbations in the spacetime can be measured by the Fourier power spectrum and bispectrum. The study of these spectra often uses the distant observer approximation where the lin e-of-sight (LOS) vectors are always parallel. But\, it has been shown that going beyond this plane-parallel assumption introduces wide-angle correct ions to the power spectrum and bispectrum. For the bisector LOS definition \, the wide-angle effects are non-negligible and can potentially contamina te local f_{NL} measurements. In this work\, we generalize the results\, b oth in the single and multi-tracer cases\, for all possible LOS definition s that can be parameterized by a free parameter in the power spectrum. We focus on low redshifts where the wide-angle effects are larger and therefo re\, we can safely neglect the lensing contribution. We consider the non-i ntegrated redshift-space distortions and relativistic Doppler and Sachs-Wo lfe terms in our perturbative expansion of the wide-angle corrections and include the primordial non-Gaussianity through the bias tracers.\n\nhttps: //partphys-indico.unige.ch/event/1441/contributions/9753/ LOCATION:Sciences II Sciences II/0-A 150 - Tingry Auditorium URL:https://partphys-indico.unige.ch/event/1441/contributions/9753/ END:VEVENT END:VCALENDAR