Spacetime structures from critical values in two-dimensional quantum gravity

Citation
V. Aldaya et Jl. Jaramillo, Spacetime structures from critical values in two-dimensional quantum gravity, CLASS QUANT, 17(7), 2000, pp. 1649-1666
Citations number
35
Categorie Soggetti
Physics
Journal title
CLASSICAL AND QUANTUM GRAVITY
ISSN journal
02649381 → ACNP
Volume
17
Issue
7
Year of publication
2000
Pages
1649 - 1666
Database
ISI
SICI code
0264-9381(20000407)17:7<1649:SSFCVI>2.0.ZU;2-5
Abstract
A model for two-dimensional (2D) quantum gravity is constructed out of the Virasoro group. To this end the quantization of the abstract Virasoro group is revisited. For the critical values of the conformal anomaly c, some qua ntum operators (SL(2, R) generators) lose their dynamical content (they are no longer conjugated operators). The notion of spacetime itself in 2D grav ity then arises as associated with this kinematical SL(2, R) symmetry. An e nsemble of different copies of AdS do co-exist in this model with different weights, depending on-their curvature (which is proportional to (h) over b ar(2)) and they are connected by gravity operators. This model suggests tha t, in general, quantum diffeomorphisms should not be imposed as constraints to the theory, except for the classical limit.