Introduction to stellar and substellar physics in modified gravity

Abstract: We discuss the standard Lane-Emden formalism as well as the one related to the slowly rotating objects. It is preceded by a brief introduction of different forms of the polytropic equation of state. This allows to study a wide class of astrophysical objects in the framework of a given theory of gravity, as demonstrated in a few examples. We will discuss light elements burning processes and cooling models in stars and substellar objects with the use of the Lane-Emden formalism.