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Gravitational Physics

3
Open Unknowns
0
Cross-Domain Bridges
2
Active Hypotheses

Open Unknowns (3)

Unknown Does the island formula (quantum extremal surface prescription) provide a complete resolution of the black hole information paradox in full quantum gravity, or only within the semiclassical approximation where the bulk geometric saddle points are well-defined — and what is the mechanism by which bulk quantum fields reconstruct the interior from boundary data after the Page time? u-black-hole-information-paradox-bulk-reconstruction
Unknown What is the precise mathematical mechanism by which AdS/CFT duality maps quantum gravity in anti-de Sitter space to conformal field theory on its boundary? u-gauge-gravity-duality-mechanism
Unknown How does quantum gravity reduce to general relativity in the semiclassical limit, and what observable corrections to GR does quantum gravity predict? u-quantum-gravity-semiclassical-limit

Active Hypotheses

Hypothesis The nanohertz gravitational wave background detected by pulsar timing arrays is dominated by a stochastic superposition of gravitational waves from supermassive black hole binary inspirals, with a characteristic strain spectrum h_c(f) ∝ f^{-2/3} confirming the circular inspiral origin, and the amplitude encoding the SMBHB merger rate × mass function. high
Hypothesis The island formula's quantum extremal surface is the gravitational analog of the decoding threshold in quantum error correction: islands appear precisely when the entanglement wedge reconstruction map transitions from reconstructing exterior to interior operators, providing a quantum-information-theoretic derivation of the Page time as the threshold for interior information recovery. medium

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Generated 2026-05-10 · USDR Dashboard