Analysis of geometric, scalar field, and thermodynamic properties of Hayward-like AdS black holes with phantom global monopoles

Abstract

In this work, we investigate the geodesic motion, scalar field perturbations, and thermodynamic properties of a static, spherically symmetric Hayward-type black hole that becomes singular due to phantom global monopoles within anti-de Sitter (AdS) spacetime. The inclusion of phantom global monopoles introduces significant modifications to the geometry and dynamics of the black hole, altering both classical trajectories and field behavior. We derive the effective potential governing the motion of test particles and analyze the effects of the Hayward-like parameter and phantom global monopoles on the stability and structure of test particle (massless and massive) orbits. Beyond the geodesic analysis, we examine spin-zero scalar field perturbations by formulating and analyzing the corresponding perturbative potential. This perturbation analysis highlights how the interaction between the Hayward-like parameter and global monopole affects the propagation of spin-zero scalar fields in the selected black hole background. Additionally, we extend our study to the thermodynamic system by computing key quantities-such as the Hawking temperature, entropy, and specific heat capacity. Our results show deviations from the standard black hole thermodynamics, particularly in the presence of phase transitions and regions of thermodynamic instability, which are influenced by both the Hayward-like parameter and phantom global monopoles.