Robustness of key features of loop quantum cosmology

Abhay Ashtekar, Alejandro Corichi, Parampreet Singh

Research output: Contribution to journalArticle

271 Citations (Scopus)

Abstract

A small simplification based on well-motivated approximations is shown to make loop quantum cosmology of the k=0 Friedman-Robertson-Walker model (with a massless scalar field) exactly soluble. Analytical methods are then used i) to show that the quantum bounce is generic; ii) to establish that the matter density has an absolute upper bound which, furthermore, equals the critical density that first emerged in numerical simulations and effective equations; iii) to bring out the precise sense in which the Wheeler-DeWitt theory approximates loop quantum cosmology and the sense in which this approximation fails; and iv) to show that discreteness underlying loop quantum cosmology is fundamental. Finally, the model is compared to analogous discussions in the literature and it is pointed out that some of their expectations do not survive a more careful examination. An effort has been made to make the underlying structure transparent also to those who are not familiar with details of loop quantum gravity.

Original languageEnglish (US)
Article number024046
JournalPhysical Review D - Particles, Fields, Gravitation and Cosmology
Volume77
Issue number2
DOIs
StatePublished - Jan 29 2008

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Quantum Cosmology
cosmology
Robustness
Bounce
Quantum Gravity
Approximation
simplification
approximation
Analytical Methods
Simplification
Scalar Field
examination
gravitation
scalars
Upper bound
Numerical Simulation
Model
simulation

All Science Journal Classification (ASJC) codes

  • Nuclear and High Energy Physics
  • Physics and Astronomy (miscellaneous)

Cite this

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Robustness of key features of loop quantum cosmology. / Ashtekar, Abhay; Corichi, Alejandro; Singh, Parampreet.

In: Physical Review D - Particles, Fields, Gravitation and Cosmology, Vol. 77, No. 2, 024046, 29.01.2008.

Research output: Contribution to journalArticle

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