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Update CP violation info

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Igor Babuschkin
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<p class="lead">You discovered CP-violation in the Kaon system.</p>
<h5><b>CP-Violation</b></h5>
<img class="img-responsive" src="assets/info/cpv.png" alt="A plot from the original publication" align="right">
<p>In the Standard Model of Particle Physics the CP-symmetry states that the laws of physics should be the same if a particle is interchanged with its antiparticle (C symmetry), and the its spatial coordinates are inverted (P symmetry). The violation of the CP-symmetry is the consequence of the appearing of a complex phase in the Cabibbo-Kobayashi-Maskawa (CKM) matrix describing the quark mixing, or the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix describing the neutrino mixing. </p>
<p class="lead">You discovered CP-violation!</p>
<h5><b>CPV in the Kaon System</b></h5>
<p>The CP-violation was discovered in 1964 by James Cronin and Val Fitch at the Alternating Gradient Synchrotron at the Brookhaven laboratory, during the investigation of the deacy of kaon. For this discovery they received the Nobel Prize in Physics in 1980.</p>
<h4>CP Symmetry</h4>
<p>C (Charge) and P (Parity) are discrete transformations that can be applied to a physical system.</p>
<p>If a theory is symmetric under C, then it works the same if all particles are exchanged with their antiparticles.
If it has P-symmetry, then it is invariant under inversion ("mirroring") of all spatial coordinates</p>
<p>For a long time, physicists believed that all of physics is invariant under the combination CP of both symmetries.
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>
<div class="container">
<div class="row">
<h5>CPV in the Kaon System</h5>
<div class="col-md-3">
<img class="img-responsive" src="assets/info/cpv.png" alt="A plot from the original publication">
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<div class="col-md-3">
<p>In 1964, Cronin, Fitch, et al. showed that CP symmetry is broken in the decay of the long-lived neutral K meson.</p>
<p>If all of physics was invariant under CP transformation, then this long-lived version of the K meson would never decay into 2 pions.</p>
<p>Yet, this kind of decay was discovered!</p>
<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>
<p>For their discovery, Cronin and Fitch received the Nobel price in 1980.</p>
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<h5><b>Resources</b></h5>
<ul>
<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>
<li><a href="http://en.wikipedia.org/wiki/CP_violation" target="_blank">CP violation on Wikipedia</a></li>
<li><a href="http://en.wikipedia.org/wiki/CP_violation" target=_blank">Wikipedia on CP violation</a></li>
<li><a href="http://en.wikipedia.org/wiki/Kaon#CP_violation_in_neutral_meson_oscillations" target="_blank">Neutral kaon mixing on Wikipedia</a></li>
</ul>
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