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arXiv · 0904.0453

Constraints on emergent gravity

Alejandro Jenkins
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Abstract

In this essay we review the central difficulty in formulating a viable quantum field theory in which gravity is emergent at low energies, rather than mediated by a fundamental gauge field. The Weinberg-Witten theorem forbids spin 2 massless modes from carrying Lorentz covariant stress-energy. In General Relativity the stress-energy is not covariant because it violates a gauge symmetry, but a gravitational theory without fundamental spin 2 gauge invariance must either lack a stress-energy operator or have a non-relativistic graviton. The latter option is incompatible with the principle of equivalence, though such theories are not necessarily ruled out at low energies.

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Alejandro Jenkins. 2009-12-15. Constraints on emergent gravity. https://doi.org/10.1142/s0218271809015941

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