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arXiv · 1811.09547

New Weyl-invariant vector-tensor theory for the cosmological constant

Pavel Jiroušek·Alexander Vikman
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Abstract

We introduce a new Weyl-invariant and generally-covariant vector-tensor theory with higher derivatives. This theory can be induced by extending the mimetic construction to vector fields of conformal weight four. We demonstrate that in gauge-invariant variables this novel theory reduces to the Henneaux-Teitelboim description of the unimodular gravity. Hence, compared with the standard general relativity, our new higher derivative vector-tensor theory has only one new global degree of freedom - the cosmological constant. Finally we discuss potential extensions of this vector-tensor theory.

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Pavel Jiroušek, Alexander Vikman. 2018-11-23. New Weyl-invariant vector-tensor theory for the cosmological constant. https://doi.org/10.1088/1475-7516%2F2019%2F04%2F004

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