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<h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Dynamotheorie</span></h1>
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<p>Die <b>Dynamotheorie</b> beschreibt die Erzeugung und das Verhalten von <a href="Magnetismus" title="Magnetismus">Magnetfeldern</a> in <a href="Elektrische_Leitf%C3%A4higkeit" title="Elektrische Leitfähigkeit">elektrisch leitfähiger</a> Materie (<a href="Plasma_(Physik)" title="Plasma (Physik)">Plasma</a>). Sie ist Teil der <a href="Magnetohydrodynamik" title="Magnetohydrodynamik">Magnetohydrodynamik</a> (MHD).<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup>
</p><p>Der „Dynamoeffekt“, also die Erzeugung von Magnetfeldern, hat seine Ursache in der <a href="Elektromagnetische_Induktion" title="Elektromagnetische Induktion">elektromagnetischen Induktion</a> aufgrund der Wechselwirkung zwischen <a href="Konvektion" title="Konvektion">Konvektion</a> in elektrisch leitender Materie und ihrer <a href="Rotation_(Physik)" title="Rotation (Physik)">Rotation</a>.
</p><p>Die Magnetfelder der Erde, der Sonne und weiterer astronomischer Objekte lassen sich durch die Dynamotheorie erklären. Zur besseren Unterscheidung von technischen Dynamos (<a href="Elektrischer_Generator" title="Elektrischer Generator">elektrische Generatoren</a>) nennt man solche Dynamos dann auch Plasmadynamos, magnetohydrodynamische oder <a href="Magnetohydrodynamischer_Dynamo" class="mw-redirect" title="Magnetohydrodynamischer Dynamo">MHD-Dynamos</a>.
</p>
<div class="mw-heading mw-heading2"><h2 id="Induktionsgleichung">Induktionsgleichung</h2></div>
<p>Die theoretische Grundlage zur Beschreibung von Dynamos bildet die Induktionsgleichung:<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup>
</p>
<dl><dd><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\partial \mathbf {B} \over \partial t}=\nabla \times (\mathbf {v} \times \mathbf {B} )-\eta \nabla \times \nabla \times \mathbf {B} }">
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<mi mathvariant="normal">∂<!-- ∂ --></mi>
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<mi mathvariant="bold">B</mi>
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<mi mathvariant="normal">∂<!-- ∂ --></mi>
<mi>t</mi>
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<mo>=</mo>
<mi mathvariant="normal">∇<!-- ∇ --></mi>
<mo>×<!-- × --></mo>
<mo stretchy="false">(</mo>
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<mi mathvariant="bold">v</mi>
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<mo>×<!-- × --></mo>
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<mi mathvariant="bold">B</mi>
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<mo stretchy="false">)</mo>
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<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">B</mi>
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<annotation encoding="application/x-tex">{\displaystyle {\partial \mathbf {B} \over \partial t}=\nabla \times (\mathbf {v} \times \mathbf {B} )-\eta \nabla \times \nabla \times \mathbf {B} }</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/912e5bd8f9cb8e60084130db9ed0d32a880f6df0.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.005ex; width:35.355ex; height:5.509ex;" alt="{\displaystyle {\partial \mathbf {B} \over \partial t}=\nabla \times (\mathbf {v} \times \mathbf {B} )-\eta \nabla \times \nabla \times \mathbf {B} }" loading="lazy"></span></dd></dl>
<p>Hierbei bedeuten:
</p>
<dl><dd><table>
<tbody><tr>
<td><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathbf {B} }">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">B</mi>
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</mrow>
<annotation encoding="application/x-tex">{\displaystyle \mathbf {B} }</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/cafb0ef39b0f5ffa23c170aa7f7b4e718327c4d1.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.901ex; height:2.176ex;" alt="{\displaystyle \mathbf {B} }" loading="lazy"></span></td>
<td><a href="Magnetismus" title="Magnetismus">Magnetfeld</a>, genauer: <a href="Magnetische_Induktion" class="mw-redirect" title="Magnetische Induktion">magnetische Induktion</a>
</td></tr>
<tr>
<td><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mathbf {v} }">
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<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">v</mi>
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</mrow>
<annotation encoding="application/x-tex">{\displaystyle \mathbf {v} }</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/35c1866e359fbfd2e0f606c725ba5cc37a5195d6.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.411ex; height:1.676ex;" alt="{\displaystyle \mathbf {v} }" loading="lazy"></span></td>
<td>Geschwindigkeitsfeld der Materie
</td></tr>
<tr>
<td><span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \eta ={1/\mu _{0}\sigma }}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>η<!-- η --></mi>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mn>1</mn>
<mrow class="MJX-TeXAtom-ORD">
<mo>/</mo>
</mrow>
<msub>
<mi>μ<!-- μ --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
</mrow>
</msub>
<mi>σ<!-- σ --></mi>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle \eta ={1/\mu _{0}\sigma }}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/be66fc76a7027b245044a7e3d5e591b41b7e3937.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:10.378ex; height:2.843ex;" alt="{\displaystyle \eta ={1/\mu _{0}\sigma }}" loading="lazy"></span></td>
<td>magnetische Diffusivität, wobei <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \mu _{0}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>μ<!-- μ --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
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<annotation encoding="application/x-tex">{\displaystyle \mu _{0}}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/fe2fd9b8decb38a3cd158e7b6c0c6e2d987fefcc.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:2.456ex; height:2.176ex;" alt="{\displaystyle \mu _{0}}" loading="lazy"></span> die <a href="Magnetische_Feldkonstante" title="Magnetische Feldkonstante">magnetische Feldkonstante</a> und <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \sigma }">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>σ<!-- σ --></mi>
</mstyle>
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<annotation encoding="application/x-tex">{\displaystyle \sigma }</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/59f59b7c3e6fdb1d0365a494b81fb9a696138c36.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.33ex; height:1.676ex;" alt="{\displaystyle \sigma }" loading="lazy"></span> die <a href="Elektrische_Leitf%C3%A4higkeit" title="Elektrische Leitfähigkeit">elektrische Leitfähigkeit</a> bedeuten.
</td></tr>
</tbody></table></dd></dl>
<p>Je höher die <a href="Magnetische_Reynoldszahl" class="mw-redirect" title="Magnetische Reynoldszahl">magnetische Reynoldszahl</a> <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle R_{m}=\mu _{0}\sigma VL}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>R</mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>m</mi>
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<mo>=</mo>
<msub>
<mi>μ<!-- μ --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
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</msub>
<mi>σ<!-- σ --></mi>
<mi>V</mi>
<mi>L</mi>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle R_{m}=\mu _{0}\sigma VL}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/ae98c3d6f9d2909b08f899821e49f77ccdb56d50.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:13.693ex; height:2.676ex;" alt="{\displaystyle R_{m}=\mu _{0}\sigma VL}" loading="lazy"></span>, die von der Geschwindigkeit <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle V}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>V</mi>
</mstyle>
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<annotation encoding="application/x-tex">{\displaystyle V}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/af0f6064540e84211d0ffe4dac72098adfa52845.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.787ex; height:2.176ex;" alt="{\displaystyle V}" loading="lazy"></span> und der Länge <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle L}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>L</mi>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle L}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/103168b86f781fe6e9a4a87b8ea1cebe0ad4ede8.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.583ex; height:2.176ex;" alt="{\displaystyle L}" loading="lazy"></span> abhängt, desto eher kann die Diffusion des Magnetfeldes (bestimmt durch <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle -\eta \nabla \times \nabla \times \mathbf {B} }">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mo>−<!-- − --></mo>
<mi>η<!-- η --></mi>
<mi mathvariant="normal">∇<!-- ∇ --></mi>
<mo>×<!-- × --></mo>
<mi mathvariant="normal">∇<!-- ∇ --></mi>
<mo>×<!-- × --></mo>
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">B</mi>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle -\eta \nabla \times \nabla \times \mathbf {B} }</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/42b661674d4862784f8df3850cdf172cacb663c2.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:14.431ex; height:2.676ex;" alt="{\displaystyle -\eta \nabla \times \nabla \times \mathbf {B} }" loading="lazy"></span>) vernachlässigt werden. In diesem Fall werden die Magnetfelder mit der Flüssigkeit transportiert und der Plasmadynamo läuft an, indem er die Magnetfelder selbst erregt.<sup id="cite_ref-Stroth-66_4-0" class="reference"><a href="#cite_note-Stroth-66-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup>
</p><p>Die Induktionsgleichung lässt sich aus den <a href="Maxwell-Gleichungen" title="Maxwell-Gleichungen">Maxwell-Gleichungen</a> <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \left({\tfrac {\partial \mathbf {B} }{\partial t}}=-\nabla \times \mathbf {E} ,\quad \nabla \times \mathbf {B} =\mu _{0}\mathbf {j} +[{\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}]\right)}">
<semantics>
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<mi mathvariant="normal">∂<!-- ∂ --></mi>
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<mi mathvariant="bold">B</mi>
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<mi mathvariant="normal">∂<!-- ∂ --></mi>
<mi>t</mi>
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</mrow>
<mo>=</mo>
<mo>−<!-- − --></mo>
<mi mathvariant="normal">∇<!-- ∇ --></mi>
<mo>×<!-- × --></mo>
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<mrow class="MJX-TeXAtom-ORD">
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<mo>=</mo>
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<mi>μ<!-- μ --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
</mrow>
</msub>
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<mi mathvariant="bold">j</mi>
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<mo stretchy="false">[</mo>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="false" scriptlevel="0">
<mfrac>
<mn>1</mn>
<msup>
<mi>c</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
</mrow>
</msup>
</mfrac>
</mstyle>
</mrow>
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<mi mathvariant="normal">∂<!-- ∂ --></mi>
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<mi>t</mi>
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</mfrac>
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<mo stretchy="false">]</mo>
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<annotation encoding="application/x-tex">{\displaystyle \left({\tfrac {\partial \mathbf {B} }{\partial t}}=-\nabla \times \mathbf {E} ,\quad \nabla \times \mathbf {B} =\mu _{0}\mathbf {j} +[{\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}]\right)}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/c0d93a6b49a6d0210a496765d52cabb4c9079aa6.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:43.257ex; height:4.843ex;" alt="{\displaystyle \left({\tfrac {\partial \mathbf {B} }{\partial t}}=-\nabla \times \mathbf {E} ,\quad \nabla \times \mathbf {B} =\mu _{0}\mathbf {j} +[{\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}]\right)}" loading="lazy"></span> und dem <a href="Ohmsches_Gesetz" title="Ohmsches Gesetz">Ohmschen Gesetz</a> <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \left(\mathbf {j} =\sigma (\mathbf {E} +\mathbf {v} \times \mathbf {B} )\right)}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow>
<mo>(</mo>
<mrow>
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">j</mi>
</mrow>
<mo>=</mo>
<mi>σ<!-- σ --></mi>
<mo stretchy="false">(</mo>
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">E</mi>
</mrow>
<mo>+</mo>
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">v</mi>
</mrow>
<mo>×<!-- × --></mo>
<mrow class="MJX-TeXAtom-ORD">
<mi mathvariant="bold">B</mi>
</mrow>
<mo stretchy="false">)</mo>
</mrow>
<mo>)</mo>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle \left(\mathbf {j} =\sigma (\mathbf {E} +\mathbf {v} \times \mathbf {B} )\right)}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/846676da3c20cec331dce3dc15ccf799736098d2.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:19.613ex; height:2.843ex;" alt="{\displaystyle \left(\mathbf {j} =\sigma (\mathbf {E} +\mathbf {v} \times \mathbf {B} )\right)}" loading="lazy"></span> unter Vernachlässigung von <span class="mwe-math-element mwe-math-element-inline"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}\approx 0}">
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<annotation encoding="application/x-tex">{\displaystyle {\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}\approx 0}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/a173d7f76a255c0566e2a3f86a06ac49156dba64.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.505ex; width:9.651ex; height:4.009ex;" alt="{\displaystyle {\tfrac {1}{c^{2}}}{\tfrac {\partial \mathbf {E} }{\partial t}}\approx 0}" loading="lazy"></span> im Rahmen der MHD herleiten.<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="Geodynamo">Geodynamo</h2></div>
<p>Die Dynamotheorie der Magnetohydrodynamik beschreibt den Geodynamo im äußeren Erdkern. In diesem erzeugen konvektive Strömungen des flüssigen Eisens das irdische Magnetfeld.
</p><p>Im äußersten Kern herrscht ein heißes, leitfähiges Metall (hauptsächlich Eisen mit leichten Beimischungen). Durch die an der Kern-Mantel-Grenze bei der Kristallisation (Wachstum des inneren Kerns) freiwerdende Schmelzenergie entstehen konvektive Strömungen. Da die Erde schnell rotiert, wirken auf diese Strömungen starke Coriolis-Kräfte, die sie zu rotationssymmetrischen, säulenförmigen Wirbeln parallel zur Erdachse organisieren. Werden diese Säulen gestreckt, wird das Magnetfeld verstärkt.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="Antidynamotheoreme">Antidynamotheoreme</h2></div>
<p>Antidynamotheoreme machen Aussagen über Bedingungen, unter denen <i>kein</i> Dynamoprozess zustande kommen kann. Sie vermitteln einen Einblick in die Funktionsweise von Dynamos, da sie die Lösungsvielfalt der Dynamogleichung einschränken, und damit aufzeigen, welche Voraussetzungen für einen funktionierenden Dynamo wesentlich sind.
</p>
<div class="mw-heading mw-heading3"><h3 id="Cowling-Theorem">Cowling-Theorem</h3></div>
<p>Das Cowling-Theorem besagt, dass ein axialsymmetrisches Magnetfeld durch keinen Dynamoprozess aufrechterhalten werden kann.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading3"><h3 id="Elsasser-Theorem">Elsasser-Theorem</h3></div>
<p>Das Elsasser-Theorem (auch Toroidal-Theorem) besagt, dass eine rein <a href="Toroidal" class="mw-redirect" title="Toroidal">toroidale</a> Strömung keinen Dynamo aufrechterhalten kann. Dies ist jedoch in einer sphärischen Geometrie nur unter der einschränkenden Bedingung der Fall, dass die elektrische Leitfähigkeit nicht winkelabhängig ist.<sup id="cite_ref-10.1103_RevModPhys.28.135_8-0" class="reference"><a href="#cite_note-10.1103_RevModPhys.28.135-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup>
</p>
<div class="mw-heading mw-heading2"><h2 id="Einzelnachweise">Einzelnachweise</h2></div>
<ol class="references">
<li id="cite_note-1"><span class="mw-cite-backlink"><a href="#cite_ref-1">↑</a></span> <span class="reference-text"><span class="cite"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20150118213104/http://www.usgs.gov/faq/?q=categories/9782/2738"><i>How does the Earth's core generate a magnetic field?</i></a> In: <i>USGS.</i> Archiviert vom <style data-mw-deduplicate="TemplateStyles:r250917974">
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/* end https://de.wikipedia.org/ */
</style><span class="dewiki-iconexternal"><a class="external text" href="https://redirecter.toolforge.org/?url=https%3A%2F%2Fwww.usgs.gov%2Fscience%2Ffaqs%3Fq%3Dcategories%2F9782%2F2738">Original</a></span> (nicht mehr online verfügbar) am <span style="white-space:nowrap;">18. Januar 2015</span><span>;</span><span class="Abrufdatum"> abgerufen am 16. Februar 2023</span>.</span><span style="display: none;" class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rfr_id=info%3Asid%2Fde.wikipedia.org%3ADynamotheorie&rft.title=How+does+the+Earth%27s+core+generate+a+magnetic+field%3F&rft.description=How+does+the+Earth%27s+core+generate+a+magnetic+field%3F&rft.identifier=https%3A%2F%2Fweb.archive.org%2Fweb%2F20150118213104%2Fhttp%3A%2F%2Fwww.usgs.gov%2Ffaq%2F%3Fq%3Dcategories%252F9782%252F2738&rft.source=https://www.usgs.gov/science/faqs?q=categories/9782/2738"> </span></span>
</li>
<li id="cite_note-2"><span class="mw-cite-backlink"><a href="#cite_ref-2">↑</a></span> <span class="reference-text">Ulrich Stroth: <cite style="font-style:italic">Plasmaphysik: Phänomene, Grundlagen und Anwendungen</cite>. 2. Auflage. Springer Spektrum, Berlin 2018, ISBN 978-3-662-55235-3, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>67</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Ulrich+Stroth&rft.btitle=Plasmaphysik%3A+Ph%C3%A4nomene%2C+Grundlagen+und+Anwendungen&rft.date=2018&rft.edition=2.&rft.genre=book&rft.isbn=9783662552353&rft.pages=67&rft.place=Berlin&rft.pub=Springer+Spektrum" style="display:none"> </span></span>
</li>
<li id="cite_note-3"><span class="mw-cite-backlink"><a href="#cite_ref-3">↑</a></span> <span class="reference-text">Alexander Piel: <cite style="font-style:italic">Plasma Physics: An Introduction to Laboratory, Space, and Fusion Plasmas</cite>. 2. Auflage. Springer-Verlag, Berlin Heidelberg New York 2017, ISBN 978-3-319-63425-8, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>129</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Alexander+Piel&rft.btitle=Plasma+Physics%3A+An+Introduction+to+Laboratory%2C+Space%2C+and+Fusion+Plasmas&rft.date=2017&rft.edition=2.&rft.genre=book&rft.isbn=9783319634258&rft.pages=129&rft.place=Berlin+Heidelberg+New+York&rft.pub=Springer-Verlag" style="display:none"> </span></span>
</li>
<li id="cite_note-Stroth-66-4"><span class="mw-cite-backlink"><a href="#cite_ref-Stroth-66_4-0">↑</a></span> <span class="reference-text">Ulrich Stroth: <cite style="font-style:italic">Plasmaphysik: Phänomene, Grundlagen und Anwendungen</cite>. 2. Auflage. Springer Spektrum, Berlin 2018, ISBN 978-3-662-55235-3, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>66</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Ulrich+Stroth&rft.btitle=Plasmaphysik%3A+Ph%C3%A4nomene%2C+Grundlagen+und+Anwendungen&rft.date=2018&rft.edition=2.&rft.genre=book&rft.isbn=9783662552353&rft.pages=66&rft.place=Berlin&rft.pub=Springer+Spektrum" style="display:none"> </span></span>
</li>
<li id="cite_note-5"><span class="mw-cite-backlink"><a href="#cite_ref-5">↑</a></span> <span class="reference-text">Ulrich Stroth: <cite style="font-style:italic">Plasmaphysik: Phänomene, Grundlagen und Anwendungen</cite>. 2. Auflage. Springer Spektrum, Berlin 2018, ISBN 978-3-662-55235-3, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>61</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Ulrich+Stroth&rft.btitle=Plasmaphysik%3A+Ph%C3%A4nomene%2C+Grundlagen+und+Anwendungen&rft.date=2018&rft.edition=2.&rft.genre=book&rft.isbn=9783662552353&rft.pages=61&rft.place=Berlin&rft.pub=Springer+Spektrum" style="display:none"> </span></span>
</li>
<li id="cite_note-6"><span class="mw-cite-backlink"><a href="#cite_ref-6">↑</a></span> <span class="reference-text">Ulrich Stroth: <cite style="font-style:italic">Plasmaphysik: Phänomene, Grundlagen und Anwendungen</cite>. 2. Auflage. Springer Spektrum, Berlin 2018, ISBN 978-3-662-55235-3, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>70</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Ulrich+Stroth&rft.btitle=Plasmaphysik%3A+Ph%C3%A4nomene%2C+Grundlagen+und+Anwendungen&rft.date=2018&rft.edition=2.&rft.genre=book&rft.isbn=9783662552353&rft.pages=70&rft.place=Berlin&rft.pub=Springer+Spektrum" style="display:none"> </span></span>
</li>
<li id="cite_note-7"><span class="mw-cite-backlink"><a href="#cite_ref-7">↑</a></span> <span class="reference-text">Michel Rieutord: <cite style="font-style:italic">Fluid Dynamics - An Introduction</cite>. Springer Verlag, New York, Berlin, Heidelberg 2015, ISBN 978-3-319-09350-5, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>397</span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.au=Michel+Rieutord&rft.btitle=Fluid+Dynamics+-+An+Introduction&rft.date=2015&rft.genre=book&rft.isbn=9783319093505&rft.pages=397&rft.place=New+York%2C+Berlin%2C+Heidelberg&rft.pub=Springer+Verlag" style="display:none"> </span></span>
</li>
<li id="cite_note-10.1103_RevModPhys.28.135-8"><span class="mw-cite-backlink"><a href="#cite_ref-10.1103_RevModPhys.28.135_8-0">↑</a></span> <span class="reference-text">Elsasser, Walter M.: <cite style="font-style:italic">Hydromagnetic Dynamo Theory</cite>. In: <cite style="font-style:italic">Reviews of Modern Physics</cite>. <span style="white-space:nowrap">Band<span style="display:inline-block;width:.2em"> </span>28</span>, <span style="white-space:nowrap">Nr.<span style="display:inline-block;width:.2em"> </span>2</span>, 1956, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>153</span>, <a href="Digital_Object_Identifier" title="Digital Object Identifier">doi</a>:<span class="uri-handle" style="white-space:nowrap"><a rel="nofollow" class="external text" href="https://doi.org/10.1103/RevModPhys.28.135">10.1103/RevModPhys.28.135</a></span>.<span class="Z3988" title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rfr_id=info:sid/de.wikipedia.org:Dynamotheorie&rft.atitle=Hydromagnetic+Dynamo+Theory&rft.au=Elsasser%2C+Walter+M.&rft.date=1956&rft.doi=10.1103%2FRevModPhys.28.135&rft.genre=journal&rft.issue=2&rft.jtitle=Reviews+of+Modern+Physics&rft.pages=153&rft.volume=28" style="display:none"> </span></span>
</li>
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