| Abstract: | Upcoming astronomical surveys like Euclid and LSST will probe the matter distribution down to scales of less than 1 Mpc/h with percent-level precision. Confronting these observations with theoretical predictions will be challenging for at least two reasons: On the one hand, these scales lie within the multi-streaming regime of collisionless dark matter dynamics where Eulerian and Lagrangian descriptions break down. On the other hand, baryonic effects like the influence of gas dynamics become relevant on these small scales. In this talk I will present an analytic framework for structure formation dubbed Kinetic Field Theory (KFT), which aims at overcoming both of these challenges without having to resort to computationally expensive numerical simulations. I will describe how KFT allows to take the actual Hamiltonian dynamics of dark matter as well as the gas dynamics of baryons into account, and show results for the power spectra obtained for both types of matter. |