The tropical Poincaré-Hopf theorem
نویسندگان
چکیده
We express the beta invariant of a loopless matroid as tropical self-intersection number diagonal its fan (a “local” Poincaré-Hopf theorem). This provides another example uncovering “geometry” matroids by expressing their invariants in terms tropicalised geometric constructions. also prove global theorem and initiate study more general Lefschetz-Hopf trace formula proving two special cases curves tori.
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ژورنال
عنوان ژورنال: Journal of Combinatorial Theory, Series A
سال: 2023
ISSN: ['0097-3165', '1096-0899']
DOI: https://doi.org/10.1016/j.jcta.2023.105733