From the computational to the observed Universe: Studying galaxy formation through stellar kinematics and strong gravitational lensing

点击翻译按钮获取中文摘要

Cosmological simulations of galaxy formation provide the most powerful technique for calculating the non-linear evolution of cosmic structure formation. This approach starts from initial conditions determined during the Big Bang - which are precisely specified in the cosmological standard model - and evolves them forward in time to the present epoch, thereby providing detailed predictions that lend themselves to testing the cosmological paradigm. At the same time, modern galaxy surveys, such as LAMOST and MaNGA, have reached an unprecedented quality and richness of their data, producing tight observational constraints on the evolution of galaxies across cosmic time. This is calling for intensified efforts to compare the computational with the observed Universe. Such a comparison promises transformative advances in our understanding of galaxy formation and answers to long standing questions in the field. This project brings together leading German and Chinese groups in galaxy formation, who have already a past history of successful collaboration. The work proposed here focuses on studying galaxy formation through stellar kinematics and strong gravitational lensing. It combines world-leading hydrodynamical simulation models with state-of-the- art analysis techniques and modern survey data. By combining the complementary expertise of the German and Chinese investigators, we aim to tackle long standing questions in the field, among them: What is the real cause of flux-ratio anomalies and what do they tell us about the viability of the CDM cosmology? What does kinematic data of galaxies reveal about their formation history? Are the internal density distributions measured for observed galaxies consistent with the dark matter cosmology? Are the chemical enrichment patterns seen in observational data reproduced in simulated galaxies? What is the frequency of galactic bars and what role do they play in setting the internal structure of galaxies? Can observations constrain the magnetic fields predicted in the simulated galaxies? Our collaboration is particularly well positioned to answer these important questions, through the use of the most advanced simulation models to date and privileged access to observational data. We will also train a new generation of astrophysicists that are at the forefront of the field, strengthening at the same time the scientific ties between the German and Chinese research communities.