Towards quantum gravity

Document Type : Review article


Department of Physics, University of Toronto, 60 St. Georges St., Toronto, ON M5S 1A7, Canada. Canadian Quantum Research Center, 204-3002 32 Ave Vernon, BC V1T 2L7, Canada


We analyze different approaches to quantum gravity. It is stressed that nonperturbative methods to quantise gravity and the usage of diffeomorphism-invariant variables are very important. We pay attention on the Wheeler--DeWitt equation in the framework of canonical quantum gravity. The Wheeler--DeWitt equation is presented in the first order formalism with the hope that this form can solve some problems such as singularities and the ordering. Also, there is a problem of defining the time.


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Volume 3, Issue 2
June 2023
Pages 53-58
  • Receive Date: 25 May 2023
  • Revise Date: 20 June 2023
  • Accept Date: 30 June 2023