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Kevin Dungs
32 lines
2.0 KiB
HTML
32 lines
2.0 KiB
HTML
<p class="lead">You discovered CP violation!</p>
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<h4>CP Symmetry</h4>
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<p data-min-level="1">C (Charge) and P (Parity) are discrete transformations that can be applied to a physical system.</p>
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<p data-min-level="1">If a theory is symmetric under C, then it works the same if all particles are exchanged with their antiparticles.
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If it has P-symmetry, then it is invariant under inversion ("mirroring") of all spatial coordinates</p>
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<p data-min-level="5">For a long time, physicists believed that all of physics is invariant under the combination CP of both symmetries.
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It turned out that this is wrong, as was discovered by Cronin, Fitch et al. in 1964 when they studied the decay of the neutral K meson.</p>
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<div class="container">
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<div class="row">
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<h5>CPV in the Kaon System</h5>
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<div class="col-md-3">
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<img class="img-responsive" src="assets/info/cpv.png" alt="A plot from the original publication">
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</div>
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<div class="col-md-3">
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<p>In 1964, Cronin, Fitch, et al. showed that CP symmetry is broken in the decay of the long-lived neutral K meson.</p>
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<p>If all of physics was invariant under CP transformation, then this long-lived version of the K meson would never decay into two pions.</p>
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<p>However, this kind of decay was discovered!</p>
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<p>You can see their results on the left: In the middle plot (the one relevant for K-meson decays), a clear excess is recognizable.</p>
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<p>For their discovery, Cronin and Fitch received the Nobel Prize in Physics in 1980.</p>
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</div>
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</div>
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<h5><b>Resources</b></h5>
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<ul>
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<li><a href="http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.13.138" target="_blank">The original publication by Cronin, Fitch et al.</a></li>
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<li><a href="http://en.wikipedia.org/wiki/CP_violation" target="_blank">Wikipedia on CP violation</a></li>
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<li><a href="http://en.wikipedia.org/wiki/Kaon#CP_violation_in_neutral_meson_oscillations" target="_blank">Neutral kaon mixing on Wikipedia</a></li>
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</ul>
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</div>
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