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arXiv · 1406.6254

On the stability and causality of scalar-vector theories

Pierre Fleury·Juan P. Beltran Almeida·Cyril Pitrou·Jean-Philippe Uzan
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Abstract

Various extensions of standard inflationary models have been proposed recently by adding vector fields. Because they are generally motivated by large-scale anomalies, and the possibility of statistical anisotropy of primordial fluctuations, such models require to introduce non-standard couplings between vector fields on the one hand, and either gravity or scalar fields on the other hand. In this article, we study models involving a vector field coupled to a scalar field. We derive restrictive necessary conditions for these models to be both stable (Hamiltonian bounded by below) and causal (hyperbolic equations of motion).

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Pierre Fleury, Juan P. Beltran Almeida, Cyril Pitrou, Jean-Philippe Uzan. 2014-11-30. On the stability and causality of scalar-vector theories. https://doi.org/10.1088/1475-7516%2F2014%2F11%2F043

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