Quantum gravity: general introduction and recent developments

  title={Quantum gravity: general introduction and recent developments},
  author={Claus Kiefer},
  journal={Annalen der Physik},
  • C. Kiefer
  • Published 29 August 2005
  • Physics
  • Annalen der Physik
I briefly review the current status of quantum gravity. After giving some general motivations for the need of such a theory, I discuss the main approaches in quantizing general relativity: Covariant approaches (perturbation theory, effective theory, and path integrals) and canonical approaches (quantum geometrodynamics, loop quantum gravity). I then address quantum gravitational aspects of string theory. This is followed by a discussion of black holes and quantum cosmology. I end with some… 

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