Researchers Demonstrate Black Holes Decohere Superpositions Via Entanglement with Internal Degrees of Freedom

Black holes, long considered simple objects defined by gravity, now appear to actively scramble information and destroy quantum coherence, a phenomenon with profound implications for our understanding of reality. Gautam Satishchandran, from the Princeton Gravity Initiative, and colleagues demonstrate how black holes achieve this decoherence, effectively dissolving quantum superpositions that venture too close to their event horizons. The research reveals three interconnected mechanisms driving this process, involving entanglement with internal components of the black hole, absorption of emitted radiation, and interactions with fluctuating quantum properties. This work clarifies the relationship between “soft hair”, subtle features on the horizon, and internal dynamics, offering new insights into the fundamental nature of horizons and potentially reshaping theories of quantum gravity.

Radiation emitted by the superposition and interactions with the quantum, fluctuating multipole moments of a black hole arising from ultra low frequency Hawking quanta are considered. The relationship between “soft hair” and interactions with “internal degrees of freedom” is emphasized, and some implications for the nature of horizons in a quantum theory of gravity are discussed.

Black Hole Interiors and Quantum Information Retrieval

This research addresses the long-standing black hole information paradox, a conflict between quantum mechanics and general relativity. Classical physics suggests information falling into a black hole is lost forever, violating a fundamental principle of quantum mechanics which states information cannot be destroyed. This work explores potential mechanisms by which information might escape, focusing on subtle quantum effects that could be observable even in these massive objects. It investigates how gravity and quantum mechanics might coexist, fundamentally altering our understanding of reality. The research investigates interconnected ideas, including “soft hair” and BMS symmetry, suggesting black holes are more complex than previously thought, possessing subtle quantum properties that could encode information.

Quantum hair, subtle quantum correlations near the black hole horizon, could potentially store information about what falls in. The team explores whether black holes possess a smooth horizon, as predicted by classical physics, or a firewall, a region of intense energy. They also consider the ER=EPR conjecture, which proposes that entangled particles are connected by wormholes, potentially allowing information to escape the black hole’s interior. A key theme is that quantum gravity effects, normally relevant only at extremely small scales, might be observable in macroscopic systems like black holes, potentially encoding information in the quantum state of the black hole and retrieving it through processes like Hawking radiation. This research is significant because it could resolve the information paradox, provide insights into the nature of quantum gravity, and suggest ways to test quantum gravity experimentally through observations of black holes. It also has implications for our understanding of the early universe and the connections between black hole physics and quantum information theory, suggesting black holes might function as quantum information processors.

Black Holes Decohere Quantum Superpositions Nearby

Researchers have demonstrated that black holes, and any horizon-like structure, fundamentally destroy quantum superpositions in their vicinity. This groundbreaking work reveals that a black hole doesn’t simply appear to possess internal degrees of freedom, but actively behaves as if it does, becoming entangled with any nearby quantum superposition. The team discovered this decoherence arises from multiple interconnected mechanisms, including entanglement with internal degrees of freedom and absorption of “soft” radiation. This soft radiation, representing ultra-low frequency gravitational waves, carries information about the superposition and entangles with the black hole, causing the quantum state to collapse.

Experiments revealed that even an observer attempting to measure the superposition from within the black hole would inevitably cause decoherence, as the black hole itself acts as the measuring device. The key finding is that the event horizon fundamentally “measures” any quantum superposition via its gravitational field, regardless of attempts to shield or isolate the experiment, occurring at a constant rate implying a universal property of black holes and horizons in any theory of quantum gravity. The research demonstrates that the horizon itself is sufficient to cause decoherence, even in scenarios where the experiment is performed adiabatically, suggesting that the very structure of the horizon, and its interaction with gravitational fields, is responsible for the observed effect, offering profound implications for our understanding of quantum gravity and the nature of information near black holes.

Horizons Inevitably Destroy Quantum Superposition

This research demonstrates that black holes, and any horizon-possessing object, inevitably cause the decoherence of quantum superpositions in their vicinity. This decoherence arises not from information loss, but from fundamental principles of quantum mechanics and causality, specifically through entanglement with degrees of freedom inside the black hole, absorption of emitted radiation, or interactions with fluctuating gravitational fields. The work establishes a connection between the “soft hair” of black holes and their internal structure, suggesting that horizons actively interact with and disrupt quantum coherence. The findings imply that maintaining quantum superposition near a black hole is impossible, not due to a breakdown of quantum mechanics, but because the horizon effectively acts as a measuring device. The authors emphasize that the gravitational field of a superposition can penetrate the horizon and induce decoherence, focusing on establishing the fundamental mechanism rather than detailing specific consequences.