Resolution of the problem of time in quantum gravity

T. A. Larsson

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arXiv · hep-th/0110166

Resolution of the problem of time in quantum gravity

T. A. Larsson

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Abstract

The metric determines the casual structure of spacetime, but in quantum gravity it is also a dynamical field which must be quantized using this causal structure; this is the famous problem of time. A radical resolution of this paradox is proposed: remove the concept of space-like separation entirely. This can be done by describing all fields in terms on p-jets, living on the observer's trajectory; all points on the trajectory have time-like separations. Such a description is necessary to construct well-defined representations the N-dimensional generalization of the Virasoro algebra Vir(N); this is the natural quantum extension of vect(N), which is the correct symmetry algebra of general relativity in N dimensions. The limit p -> oo, necessary for a field theory interpretation, only exists if N = 4 and there are three fermions for every two bosons, a relation that is satisfied in the standard model coupled to gravity.

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T. A. Larsson. 2003-06-17. Resolution of the problem of time in quantum gravity. https://arxiv.org/abs/hep-th/0110166

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