Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Quick Search
My eDoc
Session History
Support Wiki
Direct access to
document ID:

          Institute: MPI für Gravitationsphysik     Collection: Canonical and Covariant Dynamics of Quantum Gravity     Display Documents

ID: 436549.0, MPI für Gravitationsphysik / Canonical and Covariant Dynamics of Quantum Gravity
(Broken) Gauge Symmetries and Constraints in Regge Calculus
Authors:Bahr, Benjamin; Dittrich, Bianca
Title of Journal:Classical and Quantum Gravity
Issue / Number:22
Sequence Number of Article:225011
Review Status:not specified
Audience:Not Specified
Abstract / Description:We will examine the issue of diffeomorphism symmetry in simplicial models of (quantum) gravity, in particular for Regge calculus. We find that for a solution with curvature there do not exist exact gauge symmetries on the discrete level. Furthermore we derive a canonical formulation that exactly matches the dynamics and hence symmetries of the covariant picture. In this canonical formulation broken symmetries lead to the replacements of constraints by so--called pseudo constraints. These considerations should be taken into account in attempts to connect spin foam models, based on the Regge action, with canonical loop quantum gravity, which aims at implementing proper constraints. We will argue that the long standing problem of finding a consistent constraint algebra for discretized gravity theories is equivalent to the problem of finding an action with exact diffeomorphism symmetries. Finally we will analyze different limits in which the pseudo constraints might turn into proper constraints. This could be helpful to infer alternative discretization schemes in which the symmetries are not broken.
External Publication Status:published
Document Type:Article
Communicated by:Bianca Dittrich
Affiliations:MPI für Gravitationsphysik/Quantum Gravity and Unified Theories
MPI für Gravitationsphysik/Canonical and Covariant Dynamics of Quantum Gravity
Full Text:
You have privileges to view the following file(s):
0905.1670v1.pdf  [367,00 Kb] [Comment:arXiv:0905.1670v1 [gr-qc]]  
cqg9_22_225011.pdf  [584,00 Kb]   
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.