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Comments on area spectra in loop quantum gravity

 

A. Corichi

 

Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México. Apartado Postal 70-543, México D.F. 04510, México e-mail: corichi@nuclecu.unam.mx.

 

Recibido el 20 de febrero de 2004.
Aceptado el 6 de julio de 2004.

 

Abstract

We examine and compare different area spectra that have been recently considered in Loop Quantum Gravity (LQG). In particular we focus our attention on an Equally Spaced (ES) spectrum operator introduced recently by Alekseev et al that has gained some attention. We show that such operator is not well defined within the LQG framework, and comment on the issues regarding area spectra and QNM frequencies.

Keywords: Quantum gravity; Area spectrum; spin networks.

 

Resumen

Se examinan y comparan diferentes espectros del operador de área considerados recientemente dentro del formalismo cuántico de lazos. En particular se considera el operador con un espectro uniformemente espaciado introducido recientemente por Alekseev et al. y que ha recibido cierta atención. Se muestra que dicho operador no está bien definido dentro del formalismo cuántico de lazos y se comenta sobre la relación entre gravedad de lazos y los modos cuasinormales de hoyos negros.

Descriptores: Gravedad cuántica; espectro de área; redes de espín.

 

PACS: 04.60.Pp; 04.70.Dy

 

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Acknowledgments

The author would like to thank C. Fleischhack for comments. This work was partially supported by a DGAPA-UNAM grant No. IN112401 and a CONACyT grant No. J32754-E.

 

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