<p>We consider the sEGB 4<i>d</i> gravitational model with a scalar field <InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq1.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="38" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varphi \left( u\right)\)</EquationSource> </InlineEquation>, Einstein and Gauss-Bonnet terms. The model action contains a potential term <InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq2.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="41" /> </InlineMediaObject> <EquationSource Format="TEX">\(U\left( \varphi \right)\)</EquationSource> </InlineEquation>, a Gauss-Bonnet coupling function <InlineEquation ID="IEq3"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq3.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="39" /> </InlineMediaObject> <EquationSource Format="TEX">\(f\left( \varphi \right)\)</EquationSource> </InlineEquation> and a parameter <InlineEquation ID="IEq4"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq4.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="53" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = \pm 1\)</EquationSource> </InlineEquation>, where <InlineEquation ID="IEq5"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq5.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="39" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = 1\)</EquationSource> </InlineEquation> corresponds to the usual scalar field, and <InlineEquation ID="IEq6"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq6.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="53" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = -1\)</EquationSource> </InlineEquation> to the phantom field. In this paper, the sEGB reconstruction procedure considered in our previous paper is applied to the metric of the Ellis-Bronnikov solution, which describes a massive wormhole in the model with a phantom field (and zero potential). For this metric, written in the Buchdal parameterization with a radial variable <i>u</i>, we find a solution of the master equation for <InlineEquation ID="IEq7"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq7.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="64" /> </InlineMediaObject> <EquationSource Format="TEX">\(f\left( \varphi \left( u\right) \right)\)</EquationSource> </InlineEquation> with the integration (reconstruction) parameter <InlineEquation ID="IEq8"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq8.gif" Format="GIF" Height="16" Rendition="HTML" Resolution="72" Type="Linedraw" Width="20" /> </InlineMediaObject> <EquationSource Format="TEX">\(C_0\)</EquationSource> </InlineEquation>. We also find expressions for <InlineEquation ID="IEq9"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq9.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="66" /> </InlineMediaObject> <EquationSource Format="TEX">\(U\left( \varphi \left( u\right) \right)\)</EquationSource> </InlineEquation> and <InlineEquation ID="IEq10"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq10.gif" Format="GIF" Height="20" Rendition="HTML" Resolution="72" Type="Linedraw" Width="83" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon \dot{\varphi }^2 = h\left( u\right)\)</EquationSource> </InlineEquation> for <InlineEquation ID="IEq11"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq4.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="53" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = \pm 1\)</EquationSource> </InlineEquation>. We prove that for all non-trivial values of the parameter <InlineEquation ID="IEq12"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq12.gif" Format="GIF" Height="17" Rendition="HTML" Resolution="72" Type="Linedraw" Width="50" /> </InlineMediaObject> <EquationSource Format="TEX">\(C_0 \ne 0\)</EquationSource> </InlineEquation> the function <InlineEquation ID="IEq13"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq13.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="36" /> </InlineMediaObject> <EquationSource Format="TEX">\(h\left( u\right)\)</EquationSource> </InlineEquation> is not of constant sign for all admissible <InlineEquation ID="IEq14"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq14.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="112" /> </InlineMediaObject> <EquationSource Format="TEX">\(u \in \left( -\infty , +\infty \right)\)</EquationSource> </InlineEquation>. This means that for a fixed value of the parameter <InlineEquation ID="IEq15"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq4.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="53" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = \pm 1\)</EquationSource> </InlineEquation> there is no non-trivial sEGB reconstruction in which the scalar field is a purely ordinary field (<InlineEquation ID="IEq16"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq5.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="39" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = 1\)</EquationSource> </InlineEquation>) or a purely phantom field (<InlineEquation ID="IEq17"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10773_2025_6139_Article_IEq17.gif" Format="GIF" Height="14" Rendition="HTML" Resolution="72" Type="Linedraw" Width="53" /> </InlineMediaObject> <EquationSource Format="TEX">\(\varepsilon = - 1\)</EquationSource> </InlineEquation>).</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

Generalized Ellis-Bronnikov Wormhole Solution in the scalar-Einstein-Gauss-Bonnet 4d Gravitational Model

  • K. K. Ernazarov

摘要

We consider the sEGB 4d gravitational model with a scalar field \(\varphi \left( u\right)\) , Einstein and Gauss-Bonnet terms. The model action contains a potential term \(U\left( \varphi \right)\) , a Gauss-Bonnet coupling function \(f\left( \varphi \right)\) and a parameter \(\varepsilon = \pm 1\) , where \(\varepsilon = 1\) corresponds to the usual scalar field, and \(\varepsilon = -1\) to the phantom field. In this paper, the sEGB reconstruction procedure considered in our previous paper is applied to the metric of the Ellis-Bronnikov solution, which describes a massive wormhole in the model with a phantom field (and zero potential). For this metric, written in the Buchdal parameterization with a radial variable u, we find a solution of the master equation for \(f\left( \varphi \left( u\right) \right)\) with the integration (reconstruction) parameter \(C_0\) . We also find expressions for \(U\left( \varphi \left( u\right) \right)\) and \(\varepsilon \dot{\varphi }^2 = h\left( u\right)\) for \(\varepsilon = \pm 1\) . We prove that for all non-trivial values of the parameter \(C_0 \ne 0\) the function \(h\left( u\right)\) is not of constant sign for all admissible \(u \in \left( -\infty , +\infty \right)\) . This means that for a fixed value of the parameter \(\varepsilon = \pm 1\) there is no non-trivial sEGB reconstruction in which the scalar field is a purely ordinary field ( \(\varepsilon = 1\) ) or a purely phantom field ( \(\varepsilon = - 1\) ).