Ateliers action Dark Energy / GDR CoPhy 2023

Session

Contributions

5 juin 2023, 15:30

IAP

13. Jemu

Jean-Eric Campagne (LAL-IN2P3-CNRS and Univ. Paris 11)

05/06/2023 15:30

This is a brief introduction to "another" simple & non-official P(k,z) CLASS emulator designed in the context of jax-cosmo library.
After a flash on Jax-Cosmo lib, I will flash the design of the emulator based on Gaussian Processes, and gives sanity check results.
Summarizing, I will mention CosmoPower-JAX and the new initiative to standardize the emulator interface in the context of the...

18. ECLAIR: a complete toolbox for cosmological inference

Stéphane Ilic (IJCLab)

05/06/2023 15:50

In this talk, I will present the ECLAIR (Ensemble of Codes for Likelihood Analysis, Inference, and Reporting) suite of codes, meant to be used as a general inference tool. It allows the sampling -- via massively parallelizable MCMC techniques -- of the posterior distribution of a set of parameters corresponding to a particular physical model, under the constraint of a number of recent...

16. CosmoFlow

Denis Werth (Sorbonne University -- IAP)

05/06/2023 16:10

Correlation functions of primordial density fluctuations provide an exciting probe of the physics governing the earliest moments of our Universe. However, the standard approach to compute them is technically challenging. Theoretical predictions are therefore available only in restricted classes of theories, which can completely bias the interpretation of data.

In this talk, I will present...

20. LyAl-Net: a neural network emulator for Lyman-α forest simulation

Chotipan Boonkongkird (Sorbonne University)

06/06/2023 15:30

I will present a demo of LyAl-Net, an emulator for cosmological simulation which has been trained on Horizon-noAGN at z-2.43. It is designed to emulate hydrogen temperature and density from any dark matter simulation with the resolution of ~0.0976 Mpc/h in the field level.

14. ESR and katz

Deaglan Bartlett (Institut d'Astrophysique de Paris (CNRS & Sorbonne Université))

06/06/2023 15:50

Symbolic Regression algorithms learn analytic expressions which fit data accurately and in a highly interpretable manner. As such, these methods can be used to help uncover "physical laws" from data or provide simple and interpretable effective descriptions of complex, non-linear phenomena. In this talk I will present two codes aimed to address this task. The first, ESR, efficiently yet...

15. JAX-LPT: differentiable Lagrangian Perturbation Theory simulator

Axel Lapel (Institut d'Astrophysique de Paris)

06/06/2023 16:10

This talk introduces JAX-LPT: a novel code implementing fast, GPU-compatible, and differentiable simulations based on first and second-order Lagrangian Perturbation Theory. JAX-LPT can facilitate the swift generation of initial conditions for N-body simulations and integrate effectively within Bayesian hierarchical models for field-level inference, contributing to a community-wide effort to...

19. A quick introduction to the RayGal data for the investigation of relativistic effects

M. Yann RASERA (LUTH/Obs. de Paris/Univ. de Paris)

07/06/2023 15:30

In this talk I will make a quick presentation of RayGal data : https://cosmo.obspm.fr/public-datasets/ . They can be used to investigate the impact of relativistic effects on the apparent shape/distribution of large scale structures (e.g. dipole of the halo cross-correlation, magnification bias, cross-correlation of two distant shells, ISW-RS effect, gravitational redshift, etc.)

17. The e-MANTIS emulator: fast predictions for the non-linear structure formation in modified gravity

Iñigo Sáez-Casares (LUTH - Universté Paris Cité - Observatoire de Paris)

07/06/2023 15:50

In order to probe modifications of gravity at cosmological scales, accurate theoretical predictions are required. N-body simulations are needed to explore the non-linear regime of structure formation, but are very time consuming. This talk presents an emulator, dubbed e-MANTIS, that performs an accurate and fast interpolation between the predictions of a given set of cosmological simulations...