Patch-wise localization with Chern-Simons forms in five dimensional supergravity
Edoardo Colombo, Vasil Dimitrov, Dario Martelli, Alberto Zaffaroni
TL;DR
This work develops a patch-wise equivariant localization framework for five-dimensional gauged supergravity with vector multiplets to compute on-shell actions of general supersymmetric solutions, including nontrivial topology and gauge-field fluxes. The on-shell Lagrangian is recast as a topological term plus a total derivative, enabling the action to be determined from topological data via localization on toric bases. The authors derive a universal localized action formula that captures bulk and boundary contributions, and verify it with explicit examples such as Kerr–Newman black holes, black rings, lenses, and solitons, both in AdS and asymptotically flat settings. They connect the topological data to thermodynamic potentials, magnetic flux quantization, and flat connections through UV–IR relations, providing a robust tool to predict entropy and thermodynamics of yet-unknown AdS solutions. The results bridge holographic extremization and the equivariant volume viewpoint, offering a powerful approach to explore a broad landscape of supersymmetric gravitational configurations without solving the full field equations explicitly.
Abstract
In this paper, using equivariant localization for foliations, we compute the on-shell action of a general class of supersymmetric solutions of five-dimensional gauged supergravity with vector multiplets. Unlike previous literature, we also allow for a non-trivial topology for the space-time as well as for the gauge fields. In practice, we achieve this by covering the spacetime manifold with patches and localizing in each patch. We derive a general formula for the on-shell action that depends on topological data only and can be used without a detailed knowledge of the solution. Our final result is relevant for the physically interesting examples of multi-center black holes, black rings and black lenses, topological solitons and Euclidean black saddles. We also show how to connect the topological data with the thermodynamic data: electrostatic potential, the magnetic fluxes and the possible flat connections of the solutions. Our formula for the on-shell action is derived in the context of gauged supergravity, but it is straightforward to take the ungauged limit. Thus, we reproduce known results for a large class of explicit asymptotically flat supersymmetric solutions, and we provide predictions for AdS solutions still to be found.
