Bosonic Fluctuations in Semiclassically Quantized Strings

Abstract

The overall focus of this thesis is the calculation of observables such as Wilson loops using string theory. In the first part of the thesis, Wilson loops are introduced. Then, the quark-antiquark potential in an AdS5×S5 background is calculated using string theory, reproducing the result by Juan Maldacena in 1998. Then, the vacuum expectation value (vev) of a circular Wilson loop is calculated in the same ten-dimensional background. The second part of the project investigates bosonic fluctuations over a classical string solution in a general curved background and interprets them in terms of intrinsic and extrinsic geometric invariants. The objective is to extend the results of the 2015 paper by Forini et al. to the action involving the antisymmetric 2 tensor. An expression for the bosonic mass matrix is obtained. The second-order fluctuations thus obtained can be used to precisely calculate the expectation value of observables such as the Wilson loop and the free energy beyond the classical order.