Non-orientable genus of a knot in punctured $\mathbb{C}P ^2$

Kouki Sato; Motoo Tange

doi:10.3836/tjm/1452806057

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arXiv · 1403.1187

Non-orientable genus of a knot in punctured $\mathbb{C}P ^2$

Kouki Sato·Motoo Tange

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Abstract

For any knot $K$ which bounds non-orientable and null-homologous surfaces $F$ in punctured $n\mathbb{C}P^2$, we construct a lower bound of the first Betti number of $F$ which consists of the signature of $K$ and the Heegaard Floer $d$-invariant of the integer homology sphere obtained by $1$-surgery along $K$. By using this lower bound, we prove that for any integer $k$, a certain knot cannot bound any surface which satisfies the above conditions and whose first Betti number is less than $k$.

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BibTeX RIS

Kouki Sato, Motoo Tange. 2014-03-05. Non-orientable genus of a knot in punctured $\mathbb{C}P ^2$. https://doi.org/10.3836/tjm%2F1452806057

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