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On the phases of strongly coupled gauge theories from holography. / James M Rafferty

Swansea University Author: James M Rafferty

Abstract

In this thesis we extract properties of strongly coupled quantum field theories using holography. Firstly, we compute the real time two point correlation functions of N = 4 supersymmetric Yang-Mills theory on dS3 x S1 with antiperiodic boundary conditions for fermions on the circle. When the circle...

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Published: 2011
Institution: Swansea University
Degree level: Doctoral
Degree name: Ph.D
URI: https://cronfa.swan.ac.uk/Record/cronfa42707
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Abstract: In this thesis we extract properties of strongly coupled quantum field theories using holography. Firstly, we compute the real time two point correlation functions of N = 4 supersymmetric Yang-Mills theory on dS3 x S1 with antiperiodic boundary conditions for fermions on the circle. When the circle radius is large, the dual geometry is the topological AdS5 black hole. Here it is possible to solve the wave equations dual to the scalar glueball and R-charge current operators and therefore the correlation functions can be calculated exactly in the limit of large N and strong coupling. Below the critical radius for the circle the topological black hole decays to the AdS bubble of nothing. Here we compute the glueball correlation function in the WKB approximation and find poles on the real axis, indicating stable bound states. The tunnelling from the topological black hole to the bubble is interpreted as a hadronization transition. In the second part we investigate three holographic theories with an imaginary chemical potential: N = 4 supersymmetric Yang-Mills coupled to fundamental flavours in the probe approximation, the same theory with flavours confined to a codimension k defect and the Sakai-Sugimoto model. There is an infinite; series of Roberge-Weiss transitions at high temperature in each of these models and a phase transition which occurs as a result of the presence of flavours in the high temperature phase. We show the latter phase transition is first order for all three models and hence it meets the Roberge-Weiss lines at triple points. We also compute the pressure due to flavours and find for both models dual to type IIB supergravity solutions it scales in a way expected from dimensional analysis. The Sakai-Sugimoto model exhibits unusual scaling. We show the models we consider are analytic in mu2 when is mu2 small.
Keywords: Theoretical physics.;Quantum physics.
College: Faculty of Science and Engineering