<p>We study the supersingular locus of a reduction at an inert prime of the Shimura variety attached to <InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="42543_2025_102_Article_IEq1.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="93" /> </InlineMediaObject> <EquationSource Format="TEX">\(\textrm{GU}(2,n-2)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <mtext>GU</mtext> <mo stretchy="false">(</mo> <mn>2</mn> <mo>,</mo> <mi>n</mi> <mo>-</mo> <mn>2</mn> <mo stretchy="false">)</mo> </mrow> </math></EquationSource> </InlineEquation>. More concretely, we realize irreducible components of the supersingular locus as closed subschemes of flag schemes over Deligne–Lusztig varieties defined by explicit conditions after taking perfections. Moreover, we study the intersections of the irreducible components. Stratifications of Deligne–Lusztig varieties defined using powers of Frobenius action appear in the description of the intersections.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

The Supersingular Locus of the Shimura Variety of \(\textrm{GU}(2,n-2)\)

  • Maria Fox,
  • Naoki Imai

摘要

We study the supersingular locus of a reduction at an inert prime of the Shimura variety attached to \(\textrm{GU}(2,n-2)\) GU ( 2 , n - 2 ) . More concretely, we realize irreducible components of the supersingular locus as closed subschemes of flag schemes over Deligne–Lusztig varieties defined by explicit conditions after taking perfections. Moreover, we study the intersections of the irreducible components. Stratifications of Deligne–Lusztig varieties defined using powers of Frobenius action appear in the description of the intersections.