Work

Partial absence of cosine problem in 3D Lorentzian spin foams

Year: 2024

Type: article

Abstract: We study the semi-classical limit of the recently proposed coherent spin foam model for (2+1) Lorentzian quantum gravity. Specifically, we analyze the gluing equations derived from the stationary phase approximation of the vertex amplitude. Typically these exhibit two solutions yielding a cosine of the Regge action. However, by inspection of the algebraic equations as well as their geometrical realization, we show in this note that the behavior is more nuanced: when all triangles are either spacelike or timelike, two solutions exist. In any other case, only a single solution is obtained, thus yielding a single Regge exponential.

Source: Classical and Quantum Gravity

DOI: 10.1088/1361-6382/ad9700

Authors: Alexander F Jercher, José D Simão, Sebastian Steinhaus

Institutions: Munich Center for Quantum Science and Technology, Friedrich Schiller University Jena, Ludwig-Maximilians-Universität München

Language: English

Topic: Noncommutative and Quantum Gravity Theories

Subfield: Statistical and Nonlinear Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $3,165

Funders: Deutsche Forschungsgemeinschaft, Munich Center for Quantum Science and Technology