2021/03/31 by Bardia H. Fahim, Masoud Ghezelbash
Mathematics · Physics and Astronomy · #Advanced Differential Geometry Research #Black Holes and Theoretical Physics #Cosmological constant #Cosmology and Gravitation Theories #Coupling constant #Dilaton #Einstein #Field (mathematics) #Geometry #Mathematical physics #Mathematics #Physics #Pure mathematics #Quantum mechanics #Type (biology) #gr-qc
paper · pdf · doi:10.1140/epjc/s10052-021-09395-z
published as The European Physical Journal C 81, 587 (2021) · 38 pages, 15 figures, two new appendices added, typos corrected
arxiv created 2021/06/30 · openalex publication_date 2021/07/01 · arxiv updated 2021/07/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We construct new classes of cosmological solution to the five dimensional Einstein-Maxwell-dilaton theory, that are non-stationary and almost conformally regular everywhere. The base geometry for the solutions is the four-dimensional Bianchi type IX geometry. In the theory, the dilaton field is coupled to the electromagnetic field and the cosmological constant term, with two different coupling constants. We consider all possible solutions with different values of the coupling constants, where the cosmological constant takes any positive, negative or zero values. In the ansatzes for the metric, dilaton and electromagnetic fields, we consider dependence on time and two spatial directions. We also consider a special case of the Bianchi type IX geometry, in which the geometry reduces to that of Eguchi-Hanson type II geometry and find a more general solution to the theory.