<p>The generalization of the Morse theory presented by Goresky and MacPherson is a landmark that divided completely the topological and geometrical study of singular spaces. Let {<InlineEquation ID="IEq5"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq5.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="35" /> </InlineMediaObject> <EquationSource Format="TEX">\(X_t\}_t\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>X</mi> <mi>t</mi> </msub> <msub> <mrow> <mo stretchy="false">}</mo> </mrow> <mi>t</mi> </msub> </mrow> </math></EquationSource> </InlineEquation> be a suitable family of germs at 0 of complete intersection varieties in <InlineEquation ID="IEq6"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq6.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="21" /> </InlineMediaObject> <EquationSource Format="TEX">\({\mathbb {C}}^n\)</EquationSource> <EquationSource Format="MATHML"><math> <msup> <mrow> <mi mathvariant="double-struck">C</mi> </mrow> <mi>n</mi> </msup> </math></EquationSource> </InlineEquation> and <InlineEquation ID="IEq7"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq7.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="81" /> </InlineMediaObject> <EquationSource Format="TEX">\(\{f_t\}_t, \{g_t\}_t\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mrow> <mo stretchy="false">{</mo> <msub> <mi>f</mi> <mi>t</mi> </msub> <mo stretchy="false">}</mo> </mrow> <mi>t</mi> </msub> <mo>,</mo> <msub> <mrow> <mo stretchy="false">{</mo> <msub> <mi>g</mi> <mi>t</mi> </msub> <mo stretchy="false">}</mo> </mrow> <mi>t</mi> </msub> </mrow> </math></EquationSource> </InlineEquation> families of non-constant polynomial functions on <InlineEquation ID="IEq8"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq8.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="22" /> </InlineMediaObject> <EquationSource Format="TEX">\(X_t\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>X</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation>. If the germs <InlineEquation ID="IEq9"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq8.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="22" /> </InlineMediaObject> <EquationSource Format="TEX">\(X_t\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>X</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation>, <InlineEquation ID="IEq10"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq10.gif" Format="GIF" Height="21" Rendition="HTML" Resolution="72" Type="Linedraw" Width="85" /> </InlineMediaObject> <EquationSource Format="TEX">\(X_t \cap f_t^{-1}(0)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>X</mi> <mi>t</mi> </msub> <mo>∩</mo> <msubsup> <mi>f</mi> <mi>t</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msubsup> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <InlineEquation ID="IEq11"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq11.gif" Format="GIF" Height="21" Rendition="HTML" Resolution="72" Type="Linedraw" Width="149" /> </InlineMediaObject> <EquationSource Format="TEX">\(X_t\cap f_t^{-1}(0) \cap g_t^{-1}(0)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>X</mi> <mi>t</mi> </msub> <mo>∩</mo> <msubsup> <mi>f</mi> <mi>t</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msubsup> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> <mo>∩</mo> <msubsup> <mi>g</mi> <mi>t</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msubsup> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> are non-degenerate, locally tame, complete intersection varieties, for each <i>t</i>,&#xa0; we prove that the difference of the Brasselet numbers, <InlineEquation ID="IEq12"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq12.gif" Format="GIF" Height="20" Rendition="HTML" Resolution="72" Type="Linedraw" Width="61" /> </InlineMediaObject> <EquationSource Format="TEX">\(\textrm{B}_{f_t,X_t}(0)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mtext>B</mtext> <mrow> <msub> <mi>f</mi> <mi>t</mi> </msub> <mo>,</mo> <msub> <mi>X</mi> <mi>t</mi> </msub> </mrow> </msub> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation> and <InlineEquation ID="IEq13"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq13.gif" Format="GIF" Height="24" Rendition="HTML" Resolution="72" Type="Linedraw" Width="103" /> </InlineMediaObject> <EquationSource Format="TEX">\(\textrm{B}_{f_t,X_t\cap g_t^{-1}(0)}(0)\)</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mtext>B</mtext> <mrow> <msub> <mi>f</mi> <mi>t</mi> </msub> <mo>,</mo> <msub> <mi>X</mi> <mi>t</mi> </msub> <mo>∩</mo> <msubsup> <mi>g</mi> <mi>t</mi> <mrow> <mo>-</mo> <mn>1</mn> </mrow> </msubsup> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </mrow> </msub> <mrow> <mo stretchy="false">(</mo> <mn>0</mn> <mo stretchy="false">)</mo> </mrow> </mrow> </math></EquationSource> </InlineEquation>, is related with the number of Morse critical points on the regular part of the Milnor fiber of <InlineEquation ID="IEq14"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq14.gif" Format="GIF" Height="17" Rendition="HTML" Resolution="72" Type="Linedraw" Width="17" /> </InlineMediaObject> <EquationSource Format="TEX">\(f_t\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>f</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation> appearing in a morsefication of <InlineEquation ID="IEq15"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq15.gif" Format="GIF" Height="12" Rendition="HTML" Resolution="72" Type="Linedraw" Width="17" /> </InlineMediaObject> <EquationSource Format="TEX">\(g_t\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>g</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation>, even in the case where <InlineEquation ID="IEq16"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="40863_2025_498_Article_IEq15.gif" Format="GIF" Height="12" Rendition="HTML" Resolution="72" Type="Linedraw" Width="17" /> </InlineMediaObject> <EquationSource Format="TEX">\(g_t\)</EquationSource> <EquationSource Format="MATHML"><math> <msub> <mi>g</mi> <mi>t</mi> </msub> </math></EquationSource> </InlineEquation> has a critical locus with arbitrary dimension. This result connects topological and geometric properties and allows us to determine some interesting formulae, mainly in terms of the combinatorial information from Newton polyhedra.</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

Stratified Morse critical points and Brasselet number on non-degenerate locally tame singularities

  • Thaís M. Dalbelo,
  • Hellen Santana

摘要

The generalization of the Morse theory presented by Goresky and MacPherson is a landmark that divided completely the topological and geometrical study of singular spaces. Let { \(X_t\}_t\) X t } t be a suitable family of germs at 0 of complete intersection varieties in \({\mathbb {C}}^n\) C n and \(\{f_t\}_t, \{g_t\}_t\) { f t } t , { g t } t families of non-constant polynomial functions on \(X_t\) X t . If the germs \(X_t\) X t , \(X_t \cap f_t^{-1}(0)\) X t f t - 1 ( 0 ) and \(X_t\cap f_t^{-1}(0) \cap g_t^{-1}(0)\) X t f t - 1 ( 0 ) g t - 1 ( 0 ) are non-degenerate, locally tame, complete intersection varieties, for each t,  we prove that the difference of the Brasselet numbers, \(\textrm{B}_{f_t,X_t}(0)\) B f t , X t ( 0 ) and \(\textrm{B}_{f_t,X_t\cap g_t^{-1}(0)}(0)\) B f t , X t g t - 1 ( 0 ) ( 0 ) , is related with the number of Morse critical points on the regular part of the Milnor fiber of \(f_t\) f t appearing in a morsefication of \(g_t\) g t , even in the case where \(g_t\) g t has a critical locus with arbitrary dimension. This result connects topological and geometric properties and allows us to determine some interesting formulae, mainly in terms of the combinatorial information from Newton polyhedra.