Acceleration and Radiation: Classical and Quantum Aspects

Ever since the works of Rohrlich and Boulware it was realized that radiation is not a covariant concept. They found that uniformly accelerated electric charges should not emit radiation with respect to co- accelerated observers. Since then, the connection between acceleration and radiation and their relation to the equivalence principle keeps puzzling the community. More recently, this issue was investigated quantum-mechanically in the framework of quantum field theory in curved space-times and it was found what appears to be a striking connection between the bremsstrahlung and the Unruh effect. In this context, zero-energy Rindler photons play a crucial role, which have kept some physicists unsettled and hesitant in accepting such connection. In this PhD project, we aim to study both classical and quantum aspects of the radiation emitted by an accelerated charge and the exact role played by zero-energy Rindler photons already at the classical realm. Building on that, we will go a step ahead and analyze the analogous problem of the gravitational radiation emitted by a uniformly accelerating mass and its relation with zero-energy (Rindler) particles and the Unruh effect. We end the project by studying the possibility of a more general definition of radiation (and under which conditions such a concept is valid).