Probing Dark Matter and Dark Energy from Our Cosmic Neighbourhood

The standard cosmological model, while remarkably successful, faces persistent tensions. A major challenge lies in accurately mapping the distribution of dark matter and reconstructing 3D velocities, as traditional mass and dynamical estimation methods often rely on oversimplified assumptions. In this talk, I will present a multi-scale research programme that bridges cutting-edge cosmological simulations with next-generation observational surveys, aiming to resolve these issues.

I will first show how we can use the Local Universe — from binary galaxy systems like the Local Group to massive clusters such as Coma — to address discrepancies in mass estimates and develop new methods for determining cosmological parameters. Using high-precision data from Gaia and forthcoming surveys such as DESI and 4MOST, together with new techniques to reconstruct 3D velocities and calibrate dynamical mass estimators against simulations like IllustrisTNG and CLUES, I will outline a timely programme that significantly reduces uncertainties in dark matter constraints. Furthermore, by employing specialised simulation suites such as Quijote-MG, we can disentangle the effects of modified gravity, dark matter, and dark energy. This synthesis of simulations, theory, and observation provides a strong, self-consistent framework to address foundational questions in cosmology and probing gravity.

Note:
David is a candidate for a faculty position in the department. 

The talk will also be broadcast on https://biu-ac-il.zoom.us/j/9290951953, and recorded