ABSTRACT
This chapter introduces the special relativistic version of spacetime and discusses classical relativistic point particles. It derives the special relativistic transformations of spacetime coordinates, the so-called Lorentz boosts, which generalize Galilei boosts. The chapter considers space and time as a unified entity, Minkowski space. It explores the relativistic generalization of the notions of force, momentum, energy, and other physical quantities. The chapter explores a manifestly relativistic version of Lagrangian mechanics. It discusses how Noether's symmetry theorem is expressed in this relativistic framework, and people derive the main conserved quantities. The constancy of light speed is an experimental fact, which people elevate to a principle. The theory of special relativity is concerned with the notion of spacetime, events and the transformations between inertial frames, where the speed of light is a universal constant, independent of any observer.
