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Discrete Approaches to Quantum Gravity in Four Dimensions.

Renate Loll1

  • 1Max-Planck-Institut für Gravitationsphysik, Schlaatzweg 1, D-14473, Potsdam, Germany.

Living Reviews in Relativity
|February 14, 2017
PubMed
Summary

Researchers explore discrete quantum gravity theories to solve a major physics problem. This review covers gauge-theoretic, Regge calculus, and dynamical triangulation methods in four dimensions.

Area of Science:

  • Theoretical Physics
  • Quantum Gravity
  • Discrete Spacetime

Background:

  • A consistent theory of quantum gravity remains an unresolved challenge in theoretical physics.
  • Discretizing spacetime and the Einstein action is a promising approach to developing quantum gravity.

Purpose of the Study:

  • To review major research areas in discrete quantum gravity.
  • To focus on strictly four-dimensional, discrete, and quantum approaches.

Main Methods:

  • Review of gauge-theoretic approaches (path-integral and Hamiltonian formulations).
  • Review of quantum Regge calculus.
  • Review of dynamical triangulations.

Main Results:

  • The abstract does not contain specific results, but outlines areas of research.

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  • Focus on methods that are strictly four-dimensional, discrete, and quantum.

    • Conclusions:

    • The reviewed approaches represent significant efforts towards a theory of quantum gravity.
    • Further research in these discrete, quantum frameworks is ongoing.