<p>Let <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10587_2025_8924_Article_IEq1.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="14" /> </InlineMediaObject> <EquationSource Format="TEX">\(\Bbbk\)</EquationSource> <EquationSource Format="MATHML"><math display="block"> <mi mathvariant="double-struck">k</mi> </math></EquationSource> </InlineEquation> be a field, and let <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10587_2025_8924_Article_IEq2.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="203" /> </InlineMediaObject> <EquationSource Format="TEX">\(S=\Bbbk[x_1, \dots, x_m, y_1, \dots, y_n]\)</EquationSource> <EquationSource Format="MATHML"><math display="block"> <mi>S</mi> <mo>=</mo> <mi mathvariant="double-struck">k</mi> <mo stretchy="false">[</mo> <msub> <mi>x</mi> <mn>1</mn> </msub> <mo>,</mo> <mo>…</mo> <mo>,</mo> <msub> <mi>x</mi> <mi>m</mi> </msub> <mo>,</mo> <msub> <mi>y</mi> <mn>1</mn> </msub> <mo>,</mo> <mo>…</mo> <mo>,</mo> <msub> <mi>y</mi> <mi>n</mi> </msub> <mo stretchy="false">]</mo> </math></EquationSource> </InlineEquation> denote a standard bigraded polynomial ring over <InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10587_2025_8924_Article_IEq1.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="14" /> </InlineMediaObject> <EquationSource Format="TEX">\(\Bbbk\)</EquationSource> <EquationSource Format="MATHML"><math display="block"> <mi mathvariant="double-struck">k</mi> </math></EquationSource> </InlineEquation>. Consider <i>M</i>, a finitely generated bigraded <i>S</i>-module, and set <i>Q</i> = 〈<i>y</i><sub>1</sub>,…, <i>y</i><sub><i>n</i></sub>〉. Assume that there exists <InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10587_2025_8924_Article_IEq4.gif" Format="GIF" Height="17" Rendition="HTML" Resolution="72" Type="Linedraw" Width="84" /> </InlineMediaObject> <EquationSource Format="TEX">\(\frak{p} \in \text{Ass}_{S}M\)</EquationSource> <EquationSource Format="MATHML"><math display="block"> <mrow> <mi mathvariant="fraktur">p</mi> </mrow> <mo>∈</mo> <msub> <mtext mathvariant="fraktur">Ass</mtext> <mrow> <mi mathvariant="fraktur">S</mi> </mrow> </msub> <mi mathvariant="fraktur">M</mi> </math></EquationSource> </InlineEquation> such that <InlineEquation ID="IEq5"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10587_2025_8924_Article_IEq5.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="139" /> </InlineMediaObject> <EquationSource Format="TEX">\(\text {cd}(Q, S/\frak{p})=j&gt;0\)</EquationSource> <EquationSource Format="MATHML"><math display="block"> <mtext>cd</mtext> <mo stretchy="false">(</mo> <mi>Q</mi> <mo>,</mo> <mi>S</mi> <mrow> <mo>/</mo> </mrow> <mrow> <mi mathvariant="fraktur">p</mi> </mrow> <mo mathvariant="fraktur" stretchy="false">)</mo> <mo mathvariant="fraktur">=</mo> <mi mathvariant="fraktur">j</mi> <mo mathvariant="fraktur">&gt;</mo> <mn mathvariant="fraktur">0</mn> </math></EquationSource> </InlineEquation>. We demonstrate that H<Stack> <sub><i>Q</i></sub> <sup><i>j</i></sup> </Stack>(<i>M</i>) is not finitely generated. Furthermore, we explore a more general version of this result.</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

Non-finitely generated bigraded local cohomology modules

  • Ahad Rahimi

摘要

Let \(\Bbbk\) k be a field, and let \(S=\Bbbk[x_1, \dots, x_m, y_1, \dots, y_n]\) S = k [ x 1 , , x m , y 1 , , y n ] denote a standard bigraded polynomial ring over \(\Bbbk\) k . Consider M, a finitely generated bigraded S-module, and set Q = 〈y1,…, yn〉. Assume that there exists \(\frak{p} \in \text{Ass}_{S}M\) p Ass S M such that \(\text {cd}(Q, S/\frak{p})=j>0\) cd ( Q , S / p ) = j > 0 . We demonstrate that H Q j (M) is not finitely generated. Furthermore, we explore a more general version of this result.