Maximum mass limit of strange stars in quadratic curvature-matter coupled gravity

Abstract

We explore the maximum mass limit of strange stars in quadratic curvature gravity with the non-minimal matter coupling. The characteristic parameters of the quadratic curvature coupling and the non-minimal matter coupling imply the contributions from higher-order curvature terms and the coupling between matter and geometry, respectively. We demonstrate, explicitly, that the conservation of energy-momentum tensor can be modified and in the case of negligible non-minimal matter coupling, the formalism of general relativity is recovered. By deriving the Tolman-Oppenheimer-Volkoff equations from the gravitational field equations and applying the MIT bag model equation of state, we obtain the corresponding mass-radius relationships for strange stars. Although the MIT bag model represents a simplified phenomenological equation of state, it remains an effective description of strange quark matter under the extreme conditions prevailing in neutron star/strange star interiors. Within the present framework, the adoption of this equation of state yields stellar radii that are in close agreement with those inferred from recent observations of compact stars as well as GW events. This consistency between theoretical predictions and observational results indicates that, despite its simplicity, the model captures essential features of dense matter and supports the reliability of the results reported in this work. Furthermore, we show that the maximum mass limit of strange stars can exceed the general relativistic counterpart. Specifically, we find that a maximum mass up to 3.11 solar mass is achievable which suggests that the lighter companion of GW190814 could plausibly be a strange star.

18 pages, 7 figures, version accepted for publication in The European Physical Journal C

References in corpus (21)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• f(R,T) gravity
• GW190814: Gravitational Waves from the Coalescence of a 23 M${}_{\odot }$ Black Hole with a 2.6 M${}_{\odot }$ Compact Object
• Extra force in $f(R)$ modified theories of gravity
• Dark Energy and Gravity
• The Mass and Radius of the Neutron Star in 4U 1820-30
• Dark energy and dark matter as curvature effects
• Dark Energy and Dark Gravity
• Extreme neutron stars from Extended Theories of Gravity
• Extended Gravity Description for the GW190814 Supermassive Neutron Star
• Causal Limit of Neutron Star Maximum Mass in $f(R)$ Gravity in View of GW190814
• The matter Lagrangian and the energy-momentum tensor in modified gravity with non-minimal coupling between matter and geometry
• Slowly rotating neutron and strange stars in $R^2$ gravity
• Dark matter and dark energy as a effects of Modified Gravity
• Strange quark matter fragmentation in astrophysical events
• Radial oscillations and stability of compact stars in $f(R,T)=R+2\beta T$ gravity
• Influence of three parameters on maximum mass and stability of strange star under linear $f(Q)-$action
• Supermassive Neutron Stars in Axion $F(R)$ Gravity
• Kaon meson condensate in neutron star matter including hyperons
• Maximal Masses of White Dwarfs for Polytropes in $R^2$ Gravity and Theoretical Constraints
• Withholding Potentials, Absence of Ghosts and Relationship between Minimal Dilatonic Gravity and f(R) Theories