Speaker
Description
A central question in quantum gravity is how the entropy of a black hole arises from its microstates. In string theory, individual microstates of D1-D5-P black holes are described by smooth, horizonless geometries known as superstrata, and holographic complexity offers a new tool to probe how these states differ from the black hole they build.
We compute the volume complexity (CV) of formation, relative to empty AdS, for the $(1,0,n)$, $(2,1,n)$ and $(2,0,n)$ superstratum families, in both their full 6D geometry and their 3D reduction. We obtain the complexity as a function of the rescaled microstate parameter $\hat{b}$ and the mode number $n$, together with its large-$n$ scaling.
Unlike BTZ, the microstate complexity is time-independent. In the supertube limit it is negative, so the microstate is simpler than the vacuum. The 3D and 6D prescriptions agree at leading order but differ at finite order, pointing to possible ambiguities in defining volume complexity in higher-dimensional embeddings.