Seminar Talk at CTP-SCU / 理论物理中心学术报告

Speaker: Rakibur Rahman 博士  (德国马克斯-普朗克引力物理研究所(AEI))

Title: The Role of Mixed-Symmetry Fields

Abstract:
Mixed-symmetry fields are unitary irreducible representations of the Poincaré group in higher dimensions and do appear in the sub-leading Regge trajectories of String Theory. However, they are absent in the original formulation of Vasiliev Theory, which include only totally symmetric fields (without multiplicity in dimensions 4 or less). What qualitative difference does it make to have mixed-symmetry tensors in the spectrum of a theory involving massive and/or massless higher spins? In view of this, we consider the free propagation of massive bosonic fields in nontrivial electromagnetic and gravitational backgrounds. We argue that consistency of the system is governed by the closure of an algebra generated by a set of Poincaré-invariant operators. This can be motivated, for example, from the theory of charged open strings in a background gauge field, where the Virasoro algebra ensures consistent propagation. We find that absence of mixed-symmetry fields amounts for the deformed system to non-analyticity in the background curvature. Analyticity of the deformations may be achieved by the inclusion of mixed-symmetry fields like in String Theory.

Time: 05/19 (Thu) 2:00pm

Venue: Physics building 323, CTP-SCU