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<h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">G-Parität</span></h1>
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<div id="mw-content-text" class="mw-body-content mw-content-ltr" lang="de" dir="ltr"><div class="mw-content-ltr mw-parser-output" lang="de" dir="ltr"><p>Die <b>G-Parität</b> ist eine multiplikative <a href="Quantenzahl" title="Quantenzahl">Quantenzahl</a>, die die Werte +1 und −1 annehmen kann. Sie verallgemeinert die <a href="C-Parit%C3%A4t" class="mw-redirect" title="C-Parität">C-Parität</a> auf Teilchen<a href="Multiplett" class="mw-redirect" title="Multiplett">multipletts</a>.
</p><p>Dies ist sinnvoll, da die <i>C</i>-Parität nur für neutrale Systeme definiert ist (so hat z. B. im <a href="Pion" title="Pion">Pionen</a>-Triplett nur das π<sup>0</sup> <i>C</i>-Parität), die <a href="Starke_Wechselwirkung" title="Starke Wechselwirkung">starke Wechselwirkung</a> jedoch unabhängig von der elektrischen Ladung wirkt (gleichermaßen auf π<sup>0</sup>, π<sup>−</sup> und π<sup>+</sup>).
</p><p>Da die <i>G</i>-Parität jeweils auf ein ganzes Multiplett angewendet wird, sieht die <a href="Ladungskonjugation" title="Ladungskonjugation">Ladungskonjugation</a> das Multiplett als ein neutrales Ganzes. Daher können nur Multipletts mit mittleren Ladungen von 0 <a href="Eigenzustand" title="Eigenzustand">Eigenzustände</a> von <i>G</i> sein, d. h. nur Multipletts, für die gilt:
</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 {\bar {Q}}={\bar {B}}={\bar {Y}}=0}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mover>
<mi>Q</mi>
<mo stretchy="false">¯<!-- ¯ --></mo>
</mover>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mover>
<mi>B</mi>
<mo stretchy="false">¯<!-- ¯ --></mo>
</mover>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mover>
<mi>Y</mi>
<mo stretchy="false">¯<!-- ¯ --></mo>
</mover>
</mrow>
</mrow>
<mo>=</mo>
<mn>0</mn>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {\bar {Q}}={\bar {B}}={\bar {Y}}=0}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/cd38383ef63bffe12b0af0bfe7e1083bbb2649f9.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:15.833ex; height:2.843ex;" alt="{\displaystyle {\bar {Q}}={\bar {B}}={\bar {Y}}=0}" loading="lazy"></span></dd></dl>
<p>mit der <a href="Elektrische_Ladung" title="Elektrische Ladung">elektrischen Ladung</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 Q}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>Q</mi>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle Q}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/8752c7023b4b3286800fe3238271bbca681219ed.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:1.838ex; height:2.509ex;" alt="{\displaystyle Q}" loading="lazy"></span>, der <a href="Baryonenzahl" title="Baryonenzahl">Baryonenzahl</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 B}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>B</mi>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle B}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/47136aad860d145f75f3eed3022df827cee94d7a.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.764ex; height:2.176ex;" alt="{\displaystyle B}" loading="lazy"></span> und der <a href="Hyperladung" title="Hyperladung">Hyperladung</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 Y}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mi>Y</mi>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle Y}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/961d67d6b454b4df2301ac571808a3538b3a6d3f.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.171ex; width:1.773ex; height:2.009ex;" alt="{\displaystyle Y}" loading="lazy"></span>.
</p>
<div class="mw-heading mw-heading2"><h2 id="Formulierung_mit_Operatoren">Formulierung mit Operatoren</h2></div>
<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 {\mathcal {G}}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}=\eta _{G}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi class="MJX-tex-caligraphic" mathvariant="script">G</mi>
</mrow>
</mrow>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mo>(</mo>
<mtable rowspacing="4pt" columnspacing="1em">
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mo>+</mo>
</mrow>
</msup>
</mtd>
</mtr>
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
</mrow>
</msup>
</mtd>
</mtr>
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mo>−<!-- − --></mo>
</mrow>
</msup>
</mtd>
</mtr>
</mtable>
<mo>)</mo>
</mrow>
</mrow>
<mo>=</mo>
<msub>
<mi>η<!-- η --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>G</mi>
</mrow>
</msub>
<mrow class="MJX-TeXAtom-ORD">
<mrow>
<mo>(</mo>
<mtable rowspacing="4pt" columnspacing="1em">
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mo>+</mo>
</mrow>
</msup>
</mtd>
</mtr>
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>0</mn>
</mrow>
</msup>
</mtd>
</mtr>
<mtr>
<mtd>
<msup>
<mi>π<!-- π --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mo>−<!-- − --></mo>
</mrow>
</msup>
</mtd>
</mtr>
</mtable>
<mo>)</mo>
</mrow>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {\mathcal {G}}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}=\eta _{G}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/99c69babec7e1f4afad122bb9fdeb03091ee823d.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -4.171ex; width:22.497ex; height:9.509ex;" alt="{\displaystyle {\mathcal {G}}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}=\eta _{G}{\begin{pmatrix}\pi ^{+}\\\pi ^{0}\\\pi ^{-}\end{pmatrix}}}" loading="lazy"></span></dd></dl>
<p>Hierbei sind <i>η<sub>G</sub></i> die <a href="Eigenwerte" class="mw-redirect" title="Eigenwerte">Eigenwerte</a> der <i>G</i>-Parität (für Pionen im Speziellen ist <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 _{G}(\pi )=-1}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>η<!-- η --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>G</mi>
</mrow>
</msub>
<mo stretchy="false">(</mo>
<mi>π<!-- π --></mi>
<mo stretchy="false">)</mo>
<mo>=</mo>
<mo>−<!-- − --></mo>
<mn>1</mn>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle \eta _{G}(\pi )=-1}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/d6f7f21c5a1607f2079d59fd2641ef037a31343e.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:11.89ex; height:2.843ex;" alt="{\displaystyle \eta _{G}(\pi )=-1}" loading="lazy"></span>).
</p><p>Der <a href="Operator_(Mathematik)" title="Operator (Mathematik)">Operator</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 {\mathcal {G}}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi class="MJX-tex-caligraphic" mathvariant="script">G</mi>
</mrow>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {\mathcal {G}}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/b8a980c59d42c003fd07fdf3646e1fb95ff82f99.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:1.392ex; height:2.343ex;" alt="{\displaystyle {\mathcal {G}}}" loading="lazy"></span> der <i>G</i>-Parität ist definiert als:
</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 {\mathcal {G}}={\mathcal {C}}\,e^{(i\pi I_{2})}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi class="MJX-tex-caligraphic" mathvariant="script">G</mi>
</mrow>
</mrow>
<mo>=</mo>
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi class="MJX-tex-caligraphic" mathvariant="script">C</mi>
</mrow>
</mrow>
<mspace width="thinmathspace"></mspace>
<msup>
<mi>e</mi>
<mrow class="MJX-TeXAtom-ORD">
<mo stretchy="false">(</mo>
<mi>i</mi>
<mi>π<!-- π --></mi>
<msub>
<mi>I</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
</mrow>
</msub>
<mo stretchy="false">)</mo>
</mrow>
</msup>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {\mathcal {G}}={\mathcal {C}}\,e^{(i\pi I_{2})}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/28fc89831a6bfb2295b507e1cd1b13959d5e8ced.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:11.776ex; height:3.009ex;" alt="{\displaystyle {\mathcal {G}}={\mathcal {C}}\,e^{(i\pi I_{2})}}" loading="lazy"></span></dd></dl>
<p>mit dem Operator <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 {\mathcal {C}}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<mrow class="MJX-TeXAtom-ORD">
<mrow class="MJX-TeXAtom-ORD">
<mi class="MJX-tex-caligraphic" mathvariant="script">C</mi>
</mrow>
</mrow>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle {\mathcal {C}}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/e7b3edab7022ca9e2976651bc59c489513ee9019.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.338ex; width:1.239ex; height:2.176ex;" alt="{\displaystyle {\mathcal {C}}}" loading="lazy"></span> der <i>C</i>-Parität und der zweiten Komponente <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 I_{2}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>I</mi>
<mrow class="MJX-TeXAtom-ORD">
<mn>2</mn>
</mrow>
</msub>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle I_{2}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/5e3506ae39df854f347365bae6f326ef4f565be5.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.077ex; height:2.509ex;" alt="{\displaystyle I_{2}}" loading="lazy"></span> des <a href="Isospin" title="Isospin">Isospins</a>. Damit ist die <i>G</i>-Parität eine Kombination aus Ladungskonjugation und einer 180°-Drehung um die 2-Achse im Isospin-Raum.
</p>
<div class="mw-heading mw-heading2"><h2 id="Formulierung_mit_Eigenwerten">Formulierung mit Eigenwerten</h2></div>
<p>Allgemein gilt
</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 \eta _{G}=\eta _{C}\,(-1)^{I}}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>η<!-- η --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>G</mi>
</mrow>
</msub>
<mo>=</mo>
<msub>
<mi>η<!-- η --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>C</mi>
</mrow>
</msub>
<mspace width="thinmathspace"></mspace>
<mo stretchy="false">(</mo>
<mo>−<!-- − --></mo>
<mn>1</mn>
<msup>
<mo stretchy="false">)</mo>
<mrow class="MJX-TeXAtom-ORD">
<mi>I</mi>
</mrow>
</msup>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle \eta _{G}=\eta _{C}\,(-1)^{I}}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/382636083fd05431928f8e62e80d2b1459de458c.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:14.642ex; height:3.176ex;" alt="{\displaystyle \eta _{G}=\eta _{C}\,(-1)^{I}}" loading="lazy"></span></dd></dl>
<p>mit dem Eigenwert <i>η<sub>C</sub></i> der <i>C</i>-Parität und dem Isospin <i>I</i>.
</p><p>Für <a href="Fermion" title="Fermion">Fermion</a>-Antifermion-Systeme wird daraus
</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 \eta _{G}=(-1)^{S+L+I}\,}">
<semantics>
<mrow class="MJX-TeXAtom-ORD">
<mstyle displaystyle="true" scriptlevel="0">
<msub>
<mi>η<!-- η --></mi>
<mrow class="MJX-TeXAtom-ORD">
<mi>G</mi>
</mrow>
</msub>
<mo>=</mo>
<mo stretchy="false">(</mo>
<mo>−<!-- − --></mo>
<mn>1</mn>
<msup>
<mo stretchy="false">)</mo>
<mrow class="MJX-TeXAtom-ORD">
<mi>S</mi>
<mo>+</mo>
<mi>L</mi>
<mo>+</mo>
<mi>I</mi>
</mrow>
</msup>
<mspace width="thinmathspace"></mspace>
</mstyle>
</mrow>
<annotation encoding="application/x-tex">{\displaystyle \eta _{G}=(-1)^{S+L+I}\,}</annotation>
</semantics>
</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/d5e3633f12129437fca2b30936a1483975897533.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:16.742ex; height:3.176ex;" alt="{\displaystyle \eta _{G}=(-1)^{S+L+I}\,}" loading="lazy"></span></dd></dl>
<p>mit dem Gesamt<a href="Spin" title="Spin">spin</a> <i>S</i> und der Gesamt-<a href="Quantenzahl#Nebenquantenzahl" title="Quantenzahl">Drehimpulsquantenzahl</a> <i>L</i>
</p><p>und für <a href="Boson" title="Boson">Boson</a>-Antiboson-Systeme
</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 \eta _{G}=(-1)^{L+I}\,}">
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<annotation encoding="application/x-tex">{\displaystyle \eta _{G}=(-1)^{L+I}\,}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/ace57e9c54089b97d42b44adee9bb53f21ec620a.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:14.403ex; height:3.176ex;" alt="{\displaystyle \eta _{G}=(-1)^{L+I}\,}" loading="lazy"></span>.</dd></dl>
<div class="mw-heading mw-heading2"><h2 id="Invarianz_und_Erhaltung">Invarianz und Erhaltung</h2></div>
<p>Die <i>G</i>-Parität ist invariant unter der starken Wechselwirkung, da diese sowohl Ladungskonjugation als auch Isospin erhält. Unter der <a href="Elektromagnetische_Wechselwirkung" title="Elektromagnetische Wechselwirkung">elektromagnetischen</a> und der <a href="Schwache_Wechselwirkung" title="Schwache Wechselwirkung">schwachen Wechselwirkung</a> ist die <i>G</i>-Parität jedoch nicht invariant.
</p><p>Da es sich um eine multiplikative Quantenzahl handelt, ist die <i>G</i>-Parität für ein System aus <i>n</i> Pionen:
</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 \eta _{G}(n)=\left(-1\right)^{n}}">
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<mi>η<!-- η --></mi>
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<mi>G</mi>
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<annotation encoding="application/x-tex">{\displaystyle \eta _{G}(n)=\left(-1\right)^{n}}</annotation>
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</math></span><img src="./_assets_/eb734a37dd21ce173a46342d1cc64c92/7392494d7e7999afd0cdedfce23730ee22000424.svg" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:14.98ex; height:3.009ex;" alt="{\displaystyle \eta _{G}(n)=\left(-1\right)^{n}}" loading="lazy"></span>.</dd></dl>
<p>Daraus ergibt sich für Prozesse, in denen nur Pionen auftauchen, eine interessante Konsequenz aus der Erhaltung von <i>G</i>: unter der starken Wechselwirkung kann sich die Anzahl der Pionen nur um eine gerade Zahl ändern.
</p>
<div class="mw-heading mw-heading2"><h2 id="Literatur">Literatur</h2></div>
<ul><li><a href="T._D._Lee" class="mw-redirect" title="T. D. Lee">T. D. Lee</a> and <a href="Chen_Ning_Yang" title="Chen Ning Yang"> C. N. Yang</a>: <cite style="font-style:italic">Charge conjugation, a new quantum number G, and selection rules concerning a nucleon-antinucleon system</cite>. In: <cite style="font-style:italic">Il Nuovo Cimento</cite>. 3. Jahrgang, <span style="white-space:nowrap">Nr.<span style="display:inline-block;width:.2em"> </span>4</span>, 1956, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>749–753</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/10.1007/BF02744530">10.1007/BF02744530</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:G-Parit%C3%A4t&rft.atitle=Charge+conjugation%2C+a+new+quantum+number+G%2C+and+selection+rules+concerning+a+nucleon-antinucleon+system&rft.au=T.+D.+Lee+and++C.+N.+Yang&rft.date=1956&rft.doi=10.1007%2FBF02744530&rft.genre=journal&rft.issue=4&rft.jtitle=Il+Nuovo+Cimento&rft.pages=749-753&rft.volume=3.+Jahrgang" style="display:none"> </span></li>
<li>Charles Goebel: <cite style="font-style:italic">Selection Rules for NN<span dir="auto" style="font-style:normal">̅</span> Annihilation</cite>. In: <cite style="font-style:italic">Phys. Rev.</cite> 103. Jahrgang, <span style="white-space:nowrap">Nr.<span style="display:inline-block;width:.2em"> </span>1</span>, 1956, <span style="white-space:nowrap">S.<span style="display:inline-block;width:.2em"> </span>258–261</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/PhysRev.103.258">10.1103/PhysRev.103.258</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:G-Parit%C3%A4t&rft.atitle=Selection+Rules+for+NN%CC%85+Annihilation&rft.au=Charles+Goebel&rft.date=1956&rft.doi=10.1103%2FPhysRev.103.258&rft.genre=journal&rft.issue=1&rft.jtitle=Phys.+Rev.&rft.pages=258-261&rft.volume=103.+Jahrgang" style="display:none"> </span></li>
<li>Christoph Berger: <i>Teilchenphysik – Eine Einführung</i>. Springer, Berlin 1992, S. 110f, ISBN 978-3-540-54218-6</li></ul></div><!--htdig_noindex--><div><div class="zim-footer">
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