Motion-induced radiation of charged particles in curved electromagnetic space

Cerenkov radiation has hinted people since its birth as a basic observable phenomenon to unfold energy transfer from kinetic energy of moving electrons to electromagnetic waves, evanescent or traveling, whose physical principle is shared by transition radiation and Bremsstrahlung as well. However, such dissipative motion-induced radiations require particles to move faster than light in medium or to encounter velocity transition to pump energy. Whereas a recent emerging Transformation Optics strategy¹ provides such a possibility, which enables manipulating light flow almost arbitrarily, for instance to invisiblize objects hidden inside an ad-hoc device-cloak, of inhomogeneous permittivity and permeability. Invariance form of Maxwell´s equations, under various coordinates, including curvilinear, guarantees light to behave according to man´s design, shaped by curved electromagnetic space, in contrast to still-flat mechanical space, asymmetrically.