Comments on critical electric and magnetic fields from holography

• Published in: The journal of high energy physics Vol. 2013; no. 1; pp. 1 - 26
• Main Authors: Bolognesi, S., Kiefer, F., Rabinovici, E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.01.2013; Springer Nature B.V
• Subjects: Barriers; Classical and Quantum Gravitation; Elementary Particles; High energy physics; Instability; Joining; Magnetic fields; Mathematical analysis; Pair production; Particle mass; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Relativity Theory; Stability; String Theory; AdS-CFT Correspondence; D-branes; Solitons Monopoles and Instantons
• ISSN: 1029-8479; 1029-8479
• DOI: 10.1007/JHEP01(2013)174

A bstract We discuss some aspects of critical electric and magnetic fields in a field theory with holographic dual description. We extend the analysis of [1], which finds a critical electric field at which the Schwinger pair production barrier drops to zero, to the case of magnetic fields. We first find that, unlike ordinary weakly coupled theories, the magnetic field is not subject to any perturbative instability originating from the presence of a tachyonic ground state in the W-boson spectrum. This follows from the large value of the ’t Hooft coupling λ, which prevents the Zeeman interaction term to overcome the particle mass at high B . Consequently, we study the next possible B-field instability, i.e. monopole pair production, which is the S-dual version of the Schwinger effect. Also in this case a critical magnetic field is expected when the tunneling barrier drops to zero. These Schwinger-type criticalities are the holographic duals, in the bulk, to the fields E or B reaching the tension of F1 or D1 strings respectively. We then discuss how this effect is modified when electric and magnetic fields are present simultaneously and dyonic states in the spectrum can be pair produced by a generic E − B background. Finally, we analyze finite temperature effects on Schwinger criticalities, i.e. in the AdS-Schwarzshild black hole background.