A Locally Finite Model for Gravity

@article{tHooft2008ALF,
  title={A Locally Finite Model for Gravity},
  author={Gerard ’t Hooft},
  journal={Foundations of Physics},
  year={2008},
  volume={38},
  pages={733-757}
}
Matter interacting classically with gravity in 3+1 dimensions usually gives rise to a continuum of degrees of freedom, so that, in any attempt to quantize the theory, ultraviolet divergences are nearly inevitable. Here, we investigate matter of a form that only displays a finite number of degrees of freedom in compact sections of space-time. In finite domains, one has only exact, analytic solutions. This is achieved by limiting ourselves to straight pieces of string, surrounded by locally flat… 
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