Geometric purity and the frame of smashing ideals

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Authors: Juan Omar Gómez, Maurcio Medina-Barcenas, Greg Stevenson, Villarreal, Bernardo, Ángel Zaldívar
Cited by: 0

Abstract

We introduce the notion of geometric purity in rigidly-compactly generated tt-categories by considering exact triangles that are pure at each tt-stalk. We develop a systematic study of this concept, including examples and applications. In particular, we show that geometric purity is, in general, strictly stronger than ordinary purity, and that it naturally leads to the notion of geometrically pure-injective objects. We prove that such objects arise as pushforwards of pure-injective objects from suitable tt-stalks. Moreover, we give a detailed analysis of indecomposable geometrically pure-injective objects in the derived category of the projective line. Under mild additional assumptions, we identify the geometric part of the Ziegler spectrum as a closed subset. As an application, we demonstrate that this new notion of purity can be used to tackle the problem of spatiality of the frame of smashing ideals via the geometric Ziegler spectrum. In particular, we show that our approach rules out the counterexamples of Balchin and Stevenson to existing methods.

Fields of Study & Subjects

Algebraic structures and combinatorial models Homotopy and Cohomology in Algebraic Topology Algebraic Geometry and Number Theory

Publication details

Journal / source
arXiv (Cornell University)
Publication date
28 January 2026
Document type
Preprint