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We study the "complexity equals volume" (CV) and "complexity equals action"(CA) conjectures by examining moments of of time symmetry for $\rm AdS_3$wormholes having $n$ asymptotic regions and arbitrary (orientable) internaltopology. For either prescription, the complexity relative to $n$ copies of the$M=0$ BTZ black hole takes the form $\Delta C = \alpha c \chi $, where $c$ isthe central charge and $\chi$ is the Euler character of the bulk time-symmetricsurface. The coefficients $\alpha_V = -4\pi/3$, $\alpha_A = 1/6 $ defined by CVand CA are independent of both temperature and any moduli controlling thegeometry inside the black hole. Comparing with the known structure of dual CFTstates in the hot wormhole limit, the temperature and moduli independence of$\alpha_V$, $\alpha_A$ implies that any CFT gate set defining either complexitycannot be local. In particular, the complexity of an efficient quantum circuitbuilding local thermofield-double-like entanglement of thermal-sized patchesdoes not depend on the separation of the patches so entangled. We also commenton implications of the (positive) sign found for $\alpha_A$, which requires theassociated complexity to decrease when handles are added to our wormhole.

We study the "complexity equals volume" (CV) and "complexity equals action"(CA) conjectures by examining moments of of time symmetry for $\rm AdS_3$wormholes having $n$ asymptotic regions and arbitrary (orientable) internaltopology. For either prescription, the complexity relative to $n$ copies of the$M=0$ BTZ black hole takes the form $\Delta C = \alpha c \chi $, where $c$ isthe central charge and $\chi$ is the Euler character of the bulk time-symmetricsurface. The coefficients $\alpha_V = -4\pi/3$, $\alpha_A = 1/6 $ defined by CVand CA are independent of both temperature and any moduli controlling thegeometry inside the black hole. Comparing with the known structure of dual CFTstates in the hot wormhole limit, the temperature and moduli independence of$\alpha_V$, $\alpha_A$ implies that any CFT gate set defining either complexitycannot be local. In particular, the complexity of an efficient quantum circuitbuilding local thermofield-double-like entanglement of thermal-sized patchesdoes not depend on the separation of the patches so entangled. We also commenton implications of the (positive) sign found for $\alpha_A$, which requires theassociated complexity to decrease when handles are added to our wormhole.

The AdS/CFT correspondence relates quantum entanglement between boundary conformal field theories and geometric connections in the dual asymptotically anti-de Sitter spacetime. We consider entangled states in the n-fold tensor product of a 1 + 1 dimensional CFT Hilbert space defined by the Euclidean path integral over a Riemann surface with n holes. In one region of moduli space, the dual bulk state is a black hole with n asymptotically AdS3 regions connected by a common wormhole, while in other regions the bulk fragments into disconnected components. We study the entanglement structure and compute the wave function explicitly in the puncture limit of the Riemann surface in terms of CFT n-point functions. We also use AdS minimal surfaces to measure entanglement more generally. In some regions of the moduli space the entanglement is entirely multipartite, though not of the GHZ type. However, even when the bulk is completely connected, there are regions of the moduli space in which the entanglement is instead almost entirely bipartite: significant entanglement occurs only between pairs of CFTs. We develop new tools to analyze intrinsically n-partite entanglement, and use these to show that for some wormholes with n similar sized horizons there is intrinsic entanglement between all n parties, and that the distillable entanglement between the asymptotic regions is at least (n + 1)/2 partite.