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The existence of local continuous spaces at the simplices level with global discrete connectivity between simplices makes the analysis of dynamical systems on simplicial complexes a challenging problem. In this work, we provide some examples of complex systems in which this representation would be a more appropriate model of real-world phenomena. Here, we generalize the concept of metaplexes to embrace that of geometric simplicial complexes, which also includes the definition of dynamical systems on them. A metaplex is formed by regions of a continuous space of any dimension interconnected by sinks and sources that works controlled by discrete (graph) operators. The definition of simplicial metaplexes given here allows the description of the diffusion dynamics of this system in a way that solves the existing problems with previous models. We make a detailed analysis of the generalities and possible extensions of this model beyond simplicial complexes, e.g., from polytopal and cell complexes to manifold complexes, and apply it to a real-world simplicial complex representing the visual cortex of a macaque.<\/jats:p>","DOI":"10.3390\/e25121599","type":"journal-article","created":{"date-parts":[[2023,11,29]],"date-time":"2023-11-29T03:48:24Z","timestamp":1701229704000},"page":"1599","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["What Is in a Simplicial Complex? A Metaplex-Based Approach to Its Structure and Dynamics"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0424-6211","authenticated-orcid":false,"given":"Manuel","family":"Miranda","sequence":"first","affiliation":[{"name":"Institute of Cross-Disciplinary Physics and Complex Systems, IFISC (UIB-CSIC), 07122 Palma de Mallorca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6202-9384","authenticated-orcid":false,"given":"Gissell","family":"Estrada-Rodriguez","sequence":"additional","affiliation":[{"name":"Departament de Matem\u00e0tica, Universitat Polit\u00e8cnica de Catalunya, 08034 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3066-7418","authenticated-orcid":false,"given":"Ernesto","family":"Estrada","sequence":"additional","affiliation":[{"name":"Institute of Cross-Disciplinary Physics and Complex Systems, IFISC (UIB-CSIC), 07122 Palma de Mallorca, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,11,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6105872","DOI":"10.1155\/2020\/6105872","article-title":"An introduction to complex systems science and its applications","volume":"2020","author":"Siegenfeld","year":"2020","journal-title":"Complexity"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Thurner, S., Hanel, R., and Klimek, P. 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