Dr. Horacio S. Vieira

My primary research interest addresses the interaction of quantum systems with gravitational fields. The theoretical studies concerning physical processes which occur in the spacetime surrounding black holes can help us to understand the physics of these interesting objects predicted by general relativity. I have specifically worked on resonant frequencies, scattering of particles and fields of different spins, and Hawking radiation.I am working in another branch of quantum gravity, namely, active and passive quantum fluctuations of spacetime geometry. I calculated the resulting mean squared fluctuations in the relative velocity of test particles. The effect of the quantum fluctuations of the spacetime geometry is given in terms of the Riemann tensor correlation function. The source of these fluctuations is taken to be gravitons in several different states.In addition to my current research, I have worked on another collaborative project dealing with the f(R) theory of gravity. I have also analyzed quantum effects in the scenarios which consider particle self- force, asymptotically safety, and Horava-Lifshitz gravities.