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arXiv · 1202.5978

On the presence of twinlike models in cosmology

D. Bazeia·J. D. Dantas
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Abstract

We study cosmological models described by a single real scalar field. We work within the first-order framework, and we show how the first-order equations simplify the investigation, leading to a direct search of twinlike theories. The procedure is used to introduce distinct models that support the same first-order equations, with the very same energy densities and pressure in flat spacetime. The presence of curvature forbids the construction of twinlike models in the cosmological scenario here investigated.

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D. Bazeia, J. D. Dantas. 2012-02-27. On the presence of twinlike models in cosmology. https://doi.org/10.1103/physrevd.85.067303

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