Influence of quantum decoherence on black hole shadow visibility and time domain echoes
Abstract
The geometric shadow of a black hole cannot observationally distinguish horizonless exotic compact objects. We break this degeneracy by mapping the fundamental quantum decoherence of the horizon (the Danielson-Satishchandran-Wald mechanism) into a macroscopic effective reflectivity ℛ. Utilizing Kerr ray tracing, we show that a partially reflective boundary (ℛ>0) generates delayed electromagnetic echoes under both specular and diffuse (Lambertian) conditions. In the spatial domain, these echoes illuminate the inner shadow and alter low-frequency visibilities, while leaving metric-governed photon subrings unchanged. The signal strength scales with the membrane compactness ε as εΓ, where Γ=0 for specular reflection and Γ→1 for diffuse re-emission due to escape-cone collapse. This brings specular reflectivities down to ℛ≃0.12 (ngEHT) and $0.04$ (BHEX) within reach of static imaging. For Sagittarius A∗, we translate these echoes into a robust time-domain signature. Using an Autocorrelation Function (ACF) pipeline, we demonstrate that single-flare echoes can be cleanly extracted from severe accretion red noise, achieving a 3σ detection for amplitudes 𝒜≳0.3 within 15 to 33 hours of continuous monitoring. This framework provides a directly deployable pathway to test black hole unitarity.
Related
- Influence of quantum decoherence on the survival of quantumness in neutrino oscillations
- Shadow signatures and near-horizon energy accumulation in coherent quantum sine-integral black holes
- Coherent quantum state corrections in RN–black holes: Photon dynamics, shadow casts, and energy backreaction
- Does the Readout Bypass Leak the Input? A Feature-Visibility Audit of Hybrid Quantum-Classical Models
- Coherence controls the visibility of frozen disorder in an open quantum chain
BibTeX
@misc{guo2026influence,
title = {{Influence of quantum decoherence on black hole shadow visibility and time domain echoes}},
author = {Sen Guo and Xin Li and Yu Liang and Kai Lin and Li-Fang Li},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.03762},
eprint = {2610.03762},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.03762},
}
RIS
TY - UNPB
TI - Influence of quantum decoherence on black hole shadow visibility and time domain echoes
AU - Sen Guo
AU - Xin Li
AU - Yu Liang
AU - Kai Lin
AU - Li-Fang Li
PY - 2026
DA - 2026/10/01
PB - arXiv
DO - 10.48550/arxiv.2610.03762
UR - https://arxiv.org/abs/2610.03762
AB - The geometric shadow of a black hole cannot observationally distinguish horizonless exotic compact objects. We break this degeneracy by mapping the fundamental quantum decoherence of the horizon (the Danielson-Satishchandran-Wald mechanism) into a macroscopic effective reflectivity ℛ. Utilizing Kerr ray tracing, we show that a partially reflective boundary (ℛ>0) generates delayed electromagnetic echoes under both specular and diffuse (Lambertian) conditions. In the spatial domain, these echoes illuminate the inner shadow and alter low-frequency visibilities, while leaving metric-governed photon subrings unchanged. The signal strength scales with the membrane compactness ε as ε^Γ, where Γ=0 for specular reflection and Γ→1 for diffuse re-emission due to escape-cone collapse. This brings specular reflectivities down to ℛ≃0.12 (ngEHT) and $0.04$ (BHEX) within reach of static imaging. For Sagittarius A^∗, we translate these echoes into a robust time-domain signature. Using an Autocorrelation Function (ACF) pipeline, we demonstrate that single-flare echoes can be cleanly extracted from severe accretion red noise, achieving a 3σ detection for amplitudes 𝒜≳0.3 within 15 to 33 hours of continuous monitoring. This framework provides a directly deployable pathway to test black hole unitarity.
ER -