English

Nucleus I: Adjunction spectra in recommender systems and descent

Category Theory 2023-10-24 v4 Artificial Intelligence Information Retrieval

Abstract

Recommender systems build user profiles using concept analysis of usage matrices. The concepts are mined as spectra and form Galois connections. Descent is a general method for spectral decomposition in algebraic geometry and topology which also leads to generalized Galois connections. Both recommender systems and descent theory are vast research areas, separated by a technical gap so large that trying to establish a link would seem foolish. Yet a formal link emerged, all on its own, bottom-up, against authors' intentions and better judgment. Familiar problems of data analysis led to a novel solution in category theory. The present paper arose from a series of earlier efforts to provide a top-down account of these developments.

Keywords

Cite

@article{arxiv.2004.07353,
  title  = {Nucleus I: Adjunction spectra in recommender systems and descent},
  author = {Dusko Pavlovic and Dominic J. D. Hughes},
  journal= {arXiv preprint arXiv:2004.07353},
  year   = {2023}
}

Comments

46 pages, 40 figures. For readability, the previous longer version has now been split into several papers. This is part I

R2 v1 2026-06-23T14:52:59.480Z