English

General affine adjunctions, Nullstellens\"atze, and dualities

Category Theory 2018-03-14 v2 General Topology Logic

Abstract

We introduce and investigate a category-theoretic abstraction of the standard "system-solution" adjunction in affine algebraic geometry. We then look further into these geometric adjunctions at different levels of generality, from syntactic categories to (possibly infinitary) equational classes of algebras. In doing so, we discuss the relationships between the dualities induced by our framework and the well-established theory of concrete dual adjunctions. In the context of general algebra we prove an analogue of Hilbert's Nullstellensatz, thereby achieving a complete characterisation of the fixed points on the algebraic side of the adjunction.

Keywords

Cite

@article{arxiv.1412.8692,
  title  = {General affine adjunctions, Nullstellens\"atze, and dualities},
  author = {Olivia Caramello and Vincenzo Marra and Luca Spada},
  journal= {arXiv preprint arXiv:1412.8692},
  year   = {2018}
}

Comments

This new version noticeably differs from the previous one. Many changes, both stylistic and mathematical, were introduced to improve readability. Some sections were cut and new ones have been introduced to compare with the existing literature

R2 v1 2026-06-22T07:47:17.268Z