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arXiv · 1812.07530

The general scalar-tensor Hamiltonian with deformed covariance

Rhiannon Cuttell·Mairi Sakellariadou
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Abstract

We derive the scalar-tensor Hamiltonian constraint to all orders of momenta when the canonical constraint algebra is deformed by a phase space function as predicted by some studies into loop quantum cosmology. We find that the momenta and spatial derivatives from gravity and matter fields must combine in a very specific form to maintain a deformed general covariance. This suggests that the deformation should be equally caused by matter field derivatives as it is by gravitational curvature. We demonstrate the cosmological consequences of a variety of deformation functions. Some cause a big bounce at high energy densities and others cause a sudden singularity.

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Rhiannon Cuttell, Mairi Sakellariadou. 2018-12-18. The general scalar-tensor Hamiltonian with deformed covariance. https://doi.org/10.1088/1361-6382%2Fab1d80

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