Bargueño, Pedro, Fuenmayor, Ernesto, Contreras, Ernesto Complexity factor for black holes in the framework of the Newman–Penrose formalism Annals of Physics. 2022, 443: 169012. https://doi.org/10.1016/j.aop.2022.169012 URI: http://hdl.handle.net/10045/124999 DOI: 10.1016/j.aop.2022.169012 ISSN: 0003-4916 (Print) Abstract: In this work, we introduce the complexity factor in the context of self-gravitating fluid distributions for the case of black holes by employing the Newman–Penrose formalism. In particular, by working with spherically symmetric and static AdS black holes, we show that the complexity factor can be interpreted in a natural way at the event horizon. Specifically, a thermodynamic interpretation for the aforementioned complexity factor in terms of a pressure partially supporting a Van der Waals-like equation of state is given. Keywords:Black holes, Complexity factor, Spectral geometry Elsevier info:eu-repo/semantics/article