Algebraic k-systems of curves

Autor: Charles Daly, Simran Nayak, Max Lahn, Jonah Gaster, Aisha Mechery
Rok vydání: 2020
Předmět:
Zdroj: Geometriae Dedicata. 209:125-134
ISSN: 1572-9168
0046-5755
DOI: 10.1007/s10711-020-00526-6
Popis: A collection $ \Delta $ of simple closed curves on an orientable surface is an algebraic $ k $-system if the algebraic intersection number $\langle \alpha,\beta \rangle$ is equal to $k $ in absolute value for every $ \alpha , \beta \in \Delta $ distinct. Generalizing a theorem of [MRT14] we compute that the maximum size of an algebraic $k$-system of curves on a surface of genus $g$ is $2g+1$ when $g\ge 3$ or $k$ is odd, and $2g$ otherwise. To illustrate the tightness in our assumptions, we present a construction of curves pairwise geometrically intersecting twice whose size grows as $g^2$.
Comment: 7 pages, 2 figures
Databáze: OpenAIRE