Multi-horizon Black Holes Enable 2-Qubit System Modelling, Unlocking Gravitational Physics

The enduring puzzle of how gravity and quantum mechanics intersect receives fresh attention with a new investigation into the behaviour of black holes, specifically the Schwarzschild-de Sitter variety. Ratchaphat Nakarachinda, from Ramkhamhaeng University, Lunchakorn Tannukij, of King Mongkut’s Institute of Technology Ladkrabang, and Pitayuth Wongjun, at Naresuan University, alongside Tanapat Deesuwan et al., demonstrate a novel approach to understanding these complex objects by modelling them as interconnected quantum bits, or qubits. The team successfully constructs a mathematical framework treating each event horizon of the black hole as a qubit, revealing correlations between them and building density matrices that describe the system’s quantum state. This work not only provides a new way to visualise black holes, but also suggests that gravity imposes stronger constraints on quantum correlations than previously understood, potentially reshaping our understanding of quantum information in extreme gravitational environments.

The study treated each event horizon, the black hole horizon and the cosmological horizon, as a single qubit, establishing a framework where these qubits exhibit correlations analogous to those found in quantum systems. This innovative method allows researchers to explore the interplay between gravity and quantum mechanics through the lens of quantum information theory. The research team constructed reduced density matrices for each subsystem, representing the two horizons, and a combined density matrix for the entire Schwarzschild-de Sitter black hole, effectively modelling the system as two correlating qubits. This construction relied on identifying the entropies of the individual horizons with those of qubits, enabling the application of quantum information principles to a gravitational system.

Black Hole Horizons as Correlated Qubits

Scientists have successfully modeled a Schwarzschild-de Sitter black hole as a system of correlated qubits, treating each event horizon as a distinct quantum bit and establishing correlations between them. The research team identified the entropies of subsystems within the black hole and used these values to construct reduced density matrices, effectively describing the quantum state of the two horizons and the black hole itself as a 2-correlating qubit system. This work represents a significant step towards reconciling gravitational physics with quantum mechanics by applying quantum information theory to black hole thermodynamics. Experiments revealed that gravitational effects impose constraints on the correlations between qubits, resulting in a lower bound more stringent than the established Araki-Lieb triangle inequality, a fundamental principle governing quantum correlations. The team’s calculations demonstrate that the established bounds on quantum correlations are modified in the presence of gravity, suggesting a deeper connection between spacetime and quantum entanglement.

Quantum Horizons, Correlated Qubits, and New Inequalities

This research successfully models a Schwarzschild-de Sitter black hole, which possesses both black hole and cosmological horizons, as a system of correlated qubits. The team achieved this by associating each horizon with a qubit and constructing the corresponding density matrices for both the individual horizons and the complete black hole system. This innovative approach allows for the exploration of quantum properties within the framework of gravitational physics, potentially bridging the gap between general relativity and quantum mechanics. The results demonstrate that gravitational effects impose stricter constraints on the correlations between qubits than those predicted by established quantum inequalities, specifically exceeding the limitations of the Araki-Lieb triangle inequality. This finding suggests that gravity fundamentally alters the nature of quantum entanglement, offering new insights into the behaviour of quantum systems in strong gravitational fields. Future research may focus on extending this qubit-based model to more complex black hole scenarios and exploring the potential connections to quantum gravity theories.