What the study found
The study shows that pointwise free and finitely generated persistence modules over a principal ideal domain can be decomposed into intervals exactly when every structure map has a free cokernel. It also shows that, in torsion-free settings, the integer persistent homology module of a filtration of topological spaces has an interval decomposition exactly when the associated persistence diagram is invariant to the choice of coefficient field.
Why the authors say this matters
The authors state that these results generalize prior work where the indexing category was finite. The study suggests a link between interval decompositions and field-independence of persistence diagrams in torsion-free settings.
What the researchers tested
The researchers studied pointwise free and finitely generated persistence modules over a principal ideal domain, indexed by a possibly infinite totally ordered poset category. They also examined integer persistent homology modules arising from filtrations of topological spaces and considered how the persistence diagram changes with coefficient field choice.
What worked and what didn't
The paper reports that interval decompositions occur if and only if every structure map has free cokernel. It also reports that, in torsion-free settings, the integer persistent homology module admits an interval decomposition if and only if the persistence diagram is invariant under the choice of coefficient field.
What to keep in mind
The abstract does not describe specific examples, datasets, or computational methods. It also does not give separate limitations beyond noting that the results extend prior finite-indexing-category work.
Key points
- Persistence modules over a principal ideal domain have interval decompositions exactly when every structure map has a free cokernel.
- For torsion-free integer persistent homology, interval decomposition is tied to persistence diagrams being invariant across coefficient fields.
- The study considers pointwise free and finitely generated modules indexed by a possibly infinite totally ordered poset category.
- The authors say their results generalize earlier work limited to finite indexing categories.
Disclosure
- Research title:
- Interval decompositions depend on free cokernels and field choice
- Authors:
- Jiajie Luo, Gregory Henselman‐Petrusek
- Publication date:
- 2026-04-21
- OpenAlex record:
- View
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