Finite size scaling in 2d causal set quantum gravity. (15th January 2018)

• Record Type: Journal Article
• Authors: Glaser, Lisa; O'Connor, Denjoe; Surya, Sumati
• Is Part Of: Classical and quantum gravity. Volume 35:Number 4(2018:Feb.)
• Publication Date: 2018-01-15
• Subjects: quantum gravity -- causal sets -- finite size scaling -- Monte Carlo simulations; Quantum gravity -- Periodicals; Gravitation -- Periodicals; Relativity (Physics) -- Periodicals; Space and time -- Periodicals; Periodicals; 521.1
• DOI: 10.1088/1361-6382/aa9540
• Languages: English
• ISSNs: 0264-9381

Abstract

Abstract: We study the dependence on size, N, of 2 d causal set quantum gravity. This theory is known to exhibit a phase transition as the analytic continuation parameter β, akin to an inverse temperature, is varied. Using a scaling analysis we find that the asymptotic regime is reached at relatively small values of N . Focussing on the 2 d causal set action S, we find that β ⟨ S ⟩ scales like N ν where the scaling exponent ν takes different values on either side of the phase transition. For β > β c we find that ν = 2 which is consistent with our analytic predictions for a non-continuum phase in the large β regime. For β < β c we find that ν = 0, consistent with a continuum phase of constant negative curvature thus suggesting a dynamically generated cosmological constant. Moreover, we find strong evidence that the phase transition is first order. Our results strongly suggest that the asymptotic regime is reached in 2 d causal set quantum gravity for N ≳ 65 .