arXiv 1509.005502015-09math.CO

A family of $m$-ovoids of parabolic quadrics

Tao Feng, Koji Momihara, Qing Xiang

备注：: 10 pages. The revised version

英文摘要：

We construct a family of $\frac{(q-1)}{2}$-ovoids of $Q(4,q)$, the parabolic quadric of $\textup{PG}(4,q)$, for $q\equiv 3\pmod 4$. The existence of $\frac{(q-1)}{2}$-ovoids of $Q(4,q)$ was only known for $q=3, 7,$ or $11$. Our construction provides the first infinite family of $\frac{(q-1)}{2}$-ovoids of $Q(4,q)$.Along the way, we also give a construction of $\frac{q+1}{2}$-ovoids in $Q(4,q)$ for $q\equiv 1\pmod 4$.

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