The evolution of white dwarfs with a varying gravitational constant

Abstract

Within the theoretical framework of some modern unification theories the constants of nature are functions of cosmological time. White dwarfs offer the possibility of testing a possible variation of G and, thus, to place constraints to these theories. We present full white dwarf evolutionary calculations in the case that G decreases with time. White dwarf evolution is computed in a self-consistent way, including the most up-to-date physical inputs, non-gray model atmospheres and a detailed core chemical composition that results from the calculation of the full evolution of progenitor stars. We find that the mechanical structure and the energy balance of white dwarfs are strongly modified by the presence of a varying G. In particular, for certain values of the rate of change of G, the evolution of cool white dwarfs is markedly affected. The impact of a varying G is more notorious in the case of more massive white dwarfs. In view of the recent results reporting that a very accurate white dwarf cooling age can be derived for the old and metal-rich open cluster NGC 6791, our study suggests that this cluster could be a potential target to constrain or detect a ypothetical secular variation of G.

5 pages, 4 figures, accepted for publication in A&A

References in corpus (16)

• The fundamental constants and their variation: observational status and theoretical motivations
• Updated Electron-Conduction Opacities: The Impact on Low-Mass Stellar Models
• New cooling sequences for old white dwarfs
• A white dwarf cooling age of 8 Gyr for NGC 6791 from physical separation processes
• Standard and Non-Standard Plasma Neutrino Emission Revisited
• Low-temperature gas opacity - AESOPUS: a versatile and quick computational tool
• A New Nucleosynthesis Constraint on the Variation of G
• Bounds on the possible evolution of the Gravitational Constant from Cosmological Type-Ia Supernovae
• New evolutionary models for massive ZZ Ceti stars: I. First results for their pulsational properties
• The Physics of crystallizing white dwarfs
• Crystallization of Carbon Oxygen Mixtures in White Dwarf Stars
• The energetics of crystallizing white dwarfs revisited again
• A new white dwarf constraint on the rate of change of the gravitational constant
• Time variation of G and αwithin models with extra dimensions
• Evolution of white dwarf stars with high-metallicity progenitors: the role of 22Ne diffusion
• Gravitational settling of 22Ne and white dwarf evolution

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