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Smooth and Oscillating Configurations in String Theory
Chennai Mathematical Institute.
We explore gravitational aspects of string theory in different contexts.
We begin by studying timelike shells and balls in AdS space that undergo oscillatory motion. We confirm that the two-point function of the boundary CFT exhibits an oscillatory behavior following the motion of the shell. We show that similar oscillatory dynamics is possible when the perfect fluid on the shell has a polytropic equation of state. Further, we show that plausible ball-like configurations in AdS also admit oscillating solutions. We also demonstrate that the weak energy condition is satisfied for all these oscillatory configurations.
We then move on to constructing smooth solutions of supergravity. We construct a linearized left-moving perturbation on two-charge non-extremal JMaRT solutions. The perturbation is constructed by matching solutions to the perturbation equations in the inner and outer regions of the geometry to leading order and is found to be smooth and normalizable.
We then employ the Riemann-Hilbert approach to the problem of studying smooth solutions. We initiate a systematic study of monodromy matrices for multi-center solutions of five-dimensional U(1)^3 supergravity. We obtain explicitly the monodromy matrices for a class of collinear Bena-Warner bubbling geometries and show that they obey properties required for an inverse scattering construction to work.