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Title: How does a single unitary theory avoid wormhole-induced ensemble averaging?
Plain: The wormhole geometries used to get the Page curve also connect separate copies of a system, which normally happens only when one averages over many random theories. A single definite theory should not behave like an average, so something must cancel these wormhole effects.
Precise: In AdS/CFT, two decoupled boundary theories have a factorized partition function $Z(J1, J2) = Z(J1) Z(J2)$, while the bulk path integral includes connected wormhole saddles that do not factorize. Determine the bulk mechanism that restores factorization for a fixed (non-averaged) dual, such as $N=4$ super-Yang-Mills at large $N$, and its effect on the replica-wormhole derivation of the Page curve. An answer is a bulk computation, in a model with a single fixed dual, showing which contributions cancel the wormhole correlations and at what order in $\exp(-S)$.
Settled by: A bulk calculation in a higher-dimensional holographic pair with a fixed dual that exhibits the cancellation of wormhole contributions to products of partition functions.
Kind: phenomenon
Answer type: mechanism
References: (empty)
Literature status: partially-resolved
Status note: Half-wormhole saddles restore factorization in SYK-type models with fixed couplings (Saad, Shenker, Stanford, Yao 2021); no comparable bulk account exists for higher-dimensional AdS/CFT as of 2026.
Posed since: 2004