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arXiv · 2607.15897

On dark sector scalar field theories driven by cosmological $c$-fields

Alex E. Bernardini·Orfeu Bertolami
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Abstract

The interplay of Hoyle-Narlikar (HN) creation field cosmology and scalar field models for the dark sector, including the generalized Chaplygin Gas (GCG), is investigated . Though originating from distinct theoretical frameworks, both the inclusion and the non-inclusion of the creation field degree of freedom (DoF) involve a scalar DoF, which addresses some of the limitations of the standard $\Lambda$CDM model. Using a Lagrangian scalar field formulation and the first-order Hamiltonian reconstruction method, the HN $c$-field dynamics is shown to be encompassed by the GCG equation of state through an equivalent modified scalar field theory. Late-time acceleration and stability of linear perturbations are derived within this unified description. Our results suggest that creation field cosmologies may be embedded in a broader class of scalar field models which encompasses subtle modifications to the Hubble expansion rate and related physical observables.

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Alex E. Bernardini, Orfeu Bertolami. 2026-07-17. On dark sector scalar field theories driven by cosmological $c$-fields. https://doi.org/10.3390/universe12070215

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