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arXiv · 2005.01041

Polarized rigid del Pezzo surfaces in low codimension

Muhammad Imran Qureshi
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Abstract

We provide explicit graded constructions of orbifold del Pezzo surfaces with rigid orbifold points of type $\left\{k_i\times\frac{1}{r_i}(1,a_i): 3\le r_i \le 10,k_i \in \ZZ_{\ge 0}\right\}$; as well-formed and quasismooth varieties embedded in some weighted projective space. In particular, we present a collection of 147 such surfaces such that their image under their anti-canonical embeddings can be described by using one of the following sets of equations: a single equation, two linearly independent equations, five maximal Pfaffians of $5\times 5$ skew symmetric matrix, and nine $2\times 2$ minors of size 3 square matrix. This is a complete classification of such surfaces under certain carefully chosen bounds on the weights of ambient weighted projective spaces and it is largely based on detailed computer-assisted searches by using the computer algebra system \textsc{magma}.

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Muhammad Imran Qureshi. 2020-05-03. Polarized rigid del Pezzo surfaces in low codimension. https://doi.org/10.3390/math8091567

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