# 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…

## 9 Citations

Piecewise Flat Gravity in 3+1 dimensions

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We study a model for gravity in 3+1 dimensions, inspired in general relativity in 2+1 dimensions. In contrast regular general relativity in 3+1 dimensions, the model postulates that space in absence…

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We consider the (3 + 1)-dimensional locally finite gravity model proposed by 't Hooft (2008 Found. Phys. 38 733–57). In particular we revisit the problem of resolving collisions of string defects. We…

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M ay 2 01 2 The new spin foam models and quantum gravity

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Piecewise flat gravitational waves

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We examine the continuum limit of the piecewise flat locally finite gravity model introduced by 't Hooft. In the linear weak field limit, we find the energy–momentum tensor and metric perturbation of…

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In this article we give a systematic definition of the recently introduced spin foam models for four dimensional quantum gravity reviewing the main results on their semiclassical limit on fixed…