Spikes and spines in 3D Lorentzian simplicial quantum gravity

التفاصيل البيبلوغرافية
العنوان: Spikes and spines in 3D Lorentzian simplicial quantum gravity
المؤلفون: Borissova, Johanna, Dittrich, Bianca, Qu, Dongxue, Schiffer, Marc
سنة النشر: 2024
المجموعة: General Relativity and Quantum Cosmology
High Energy Physics - Theory
مصطلحات موضوعية: General Relativity and Quantum Cosmology, High Energy Physics - Theory
الوصف: Simplicial approaches to quantum gravity such as Quantum Regge Calculus and Spin Foams include configurations where bulk edges can become arbitrarily large while keeping the lengths of the boundary edges small. Such configurations pose significant challenges in Euclidean Quantum Regge Calculus, as they lead to infinities for the partition function and length expectation values. Here we investigate such configurations in three-dimensional Lorentzian Quantum Regge Calculus, and find that the partition function and length expectation values remain finite. This shows that the Lorentzian approach can avoid a key issue of the Euclidean approach. We also find that the space of configurations, for which bulk edges can become very large, is much richer than in the Euclidean case. In particular, it includes configurations with irregular light-cone structures, which lead to imaginary terms in the Regge action and branch cuts along the Lorentzian path integral contour. Hence, to meaningfully define the Lorentzian Regge path integral, one needs to clarify how such configurations should be handled.
Comment: v1: 31 pages, 13 figures
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2406.19169
رقم الأكسشن: edsarx.2406.19169
قاعدة البيانات: arXiv