Charged Black Hole Thermodynamics Modified by Non-Minimal Coupling and Entropy Corrections

Black holes, enigmatic objects with immense gravitational pull, continue to challenge our understanding of physics, and new research explores their thermodynamic properties and how light bends around them in extreme conditions. Erdem Sucu, Izzet Sakallı, and Ozcan Sert, from Eastern Mediterranean University and Pamukkale University, alongside Yusuf Sucu from Akdeniz University, investigate black holes within a modified theory of gravity, incorporating the effects of electromagnetic fields and the presence of plasma. Their work reveals that these black holes exhibit unique thermodynamic instabilities and lensing behaviours, differing significantly from predictions made by Einstein’s general relativity, and potentially offering new ways to probe the nature of gravity and the universe’s most extreme environments. The team’s analysis demonstrates how the interplay between gravity, electromagnetism, and plasma can dramatically alter the behaviour of black holes, with heat engines operating in these geometries achieving remarkably high efficiencies and light bending exhibiting frequency-dependent signatures.

Their work reveals that altering how gravity and electromagnetism interact can dramatically change the characteristics of black holes, including the very existence of event horizons. The team discovered that increasing the strength of this interaction can lead to the formation of naked singularities, potentially violating a long-held principle in physics known as cosmic censorship.

Black Hole Spacetimes and Quantum Gravity Studies

This extensive list comprises publications related to astrophysics, general relativity, black holes, quantum gravity, and related topics, representing a comprehensive research area. It encompasses studies of black hole shadows, accretion disks, jets, and the properties of black hole spacetimes, alongside solutions to Einstein’s field equations, tests of general relativity, and alternative theories of gravity. A significant number explore approaches to quantizing gravity, including loop quantum gravity and string theory, alongside work on black hole entropy and information paradoxes. The list also includes studies of jets emanating from black holes and active galactic nuclei, as well as the physics of accretion disks, cosmological models, and gravitational waves.

Exploration of theories beyond standard General Relativity and numerical simulations of black holes and gravitational phenomena are also prominent. The collection demonstrates a theoretical focus, with an emphasis on mathematical modeling and analysis, but also incorporates observational work, such as the Event Horizon Telescope and gravitational wave detections. This list would be an excellent starting point for a literature review, a foundation for a research project, or material for a graduate-level course on black holes, general relativity, or quantum gravity. It could also be used to identify leading researchers in the field and track the evolution of research in these areas over time. To enhance its usefulness, categorizing the papers, adding abstracts or keywords, and providing links to the publications would be beneficial.

Electromagnetism Alters Black Hole Event Horizons

Researchers have investigated black holes within the framework of symmetric teleparallel gravity, exploring how the strength of electromagnetic forces affects their structure and behavior. Their work reveals that by altering how gravity and electromagnetism interact, the characteristics of black holes, including the very existence of event horizons, can be dramatically changed. The team discovered that increasing the strength of this interaction can lead to the formation of naked singularities, potentially violating a long-held principle in physics known as cosmic censorship. The research demonstrates a sensitive relationship between the black hole’s properties and the coupling parameter, which governs the strength of the interaction between gravity and electromagnetism.

For certain combinations of this parameter and the black hole’s electric charge, the spacetime transitions from configurations with two distinct horizons to those with only one, or even no horizon at all, suggesting that the non-minimal coupling significantly modifies the causal structure of spacetime around these objects. Furthermore, the study extends to analyzing thermodynamic properties, revealing that the modified gravity theory impacts the efficiency of heat engines operating near the black hole, potentially approaching 99% efficiency under optimal conditions. The team also calculated how light bends around these black holes, finding that the interplay between the non-minimal coupling and the presence of plasma creates unique lensing signatures that differ from those predicted by Einstein’s general relativity, offering a potential observational pathway to distinguish this modified gravity from standard general relativity.

Charged Black Holes and Enhanced Heat Engine Efficiency

This research investigates electrically charged black holes within the framework of symmetric teleparallel gravity, incorporating the effects of electromagnetic coupling and plasma dispersion. The study demonstrates that non-minimal electromagnetic coupling modifies the standard black hole structure, preserving the existence of both inner and outer horizons for appropriate parameter ranges. Analysis of thermodynamic quantities reveals enhanced instability under strong coupling conditions and distinct cooling and heating behaviours in Joule-Thomson expansions, with charge enhancing the efficiency of heat engines operating in this geometry, approaching near-ideal performance. Furthermore, the research extends to gravitational lensing, demonstrating that non-minimal coupling and plasma environments create unique, frequency-dependent deflection angles that differ from predictions based on general relativity. The team derived analytical expressions for these angles using the Gauss-Bonnet theorem, highlighting potential observational signatures for distinguishing this modified gravity theory from standard models.