MonkeyGG2
72 lines
4.1 KiB
HTML
72 lines
4.1 KiB
HTML
<p class="lead">You discovered CP violation!</p>
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<section data-min-level="1">
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<h4>The Mystery of CP Violation</h4>
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<p>
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The study of CP violation is concerned with some very fundamental questions:<br>
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<ul>
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<li>Are the laws of physics different for matter and antimatter?</li>
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<li>Why is there an abundance of matter in our universe, instead of equal amounts of matter and antimatter?</li>
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</ul>
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</p>
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</section>
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<section data-min-level="5">
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<h4>What is CP?</h4>
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<p>
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CP is a possible <em>symmetry</em> of nature.
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If the laws of nature were symmetric under CP, then matter and antimatter would be governed by the same rules.
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This means that if we communicated with aliens from a distant galaxy, there would be no way to find out if they are made from matter or antimatter:
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No experiment they could perform would allow us to deduce if they lived in a matter or antimatter world.
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On the other hand, if there was a fundamental difference between matter and antimatter, such an experiment would be possible.
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It turns out that this is the case in our universe!
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</p>
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</section>
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<section data-min-level="10">
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<h4>How was CP violation discovered?</h4>
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<p>
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In 1964, a team lead by Val Fitch and Jim Cronin performed experiments with <em>neutral Kaons</em>, particles formed by a strange and an anti-down quark.
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These neutral Kaons have the amazing property that they can spontaneously transform into their own antiparticle.
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Fitch and Cronin discovered that the rate at which these Kaons changed from matter to antimatter and vice versa was different, clear evidence for CP violation!
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This discovery came as a total surprise to physicists (it was assumed that nature was symmetric under CP) and earned Cronin and Fitch the <a target="_blank" href="http://www.nobelprize.org/nobel_prizes/physics/laureates/1980/">Nobel Prize</a> in 1980.
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</p>
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</section>
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<section data-min-level="15">
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<h4>How is CP violation currently understood?</h4>
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<p>
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In 1973, two Japanese physicists, <a target="_blank" href="http://en.wikipedia.org/wiki/Makoto_Kobayashi_(physicist)">Makoto Kobayashi</a> and <a target="_blank" href="http://en.wikipedia.org/wiki/Toshihide_Maskawa">Toshihide Maskawa</a>, found a very simple and elegant way to explain the occurrence of CP violation in our universe.
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The only problem: The explanation required a third generation of quarks (the <em>top</em> and <em>bottom</em> quarks) for which there was zero evidence at the time.
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</p>
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<p>
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This turned out to be an incredible prediction, when both of these quarks were discovered decades later.
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So far, the idea of Kobayashi and Maskawa, called the <a target="_blank" href="http://en.wikipedia.org/wiki/Cabibbo–Kobayashi–Maskawa_matrix">CKM mechanism</a>, has been able to explain every single occurrence of CP violation that physicists managed to detect in the lab.
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They were awarded the Nobel Prize in 2008.
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</p>
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</section>
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<section data-min-level="20">
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<h4>What's next for CP violation?</h4>
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<p>
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CP violation is one of the necessary ingredients for explaining the abundance of matter over antimatter in our universe.
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But there is one problem: The CKM mechanism predicts too little of it.
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The amount of matter in our universe suggests that a correction or even a complete revolution in our understanding of CP violation is necessary.
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</p>
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<p>
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CP violation remains a hot topic in Physics research.
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Specialized experiments like the <a href="http://lhcb-public.web.cern.ch/lhcb-public/Welcome.html">LHCb detector</a> at CERN in Switzerland are currently searching for hints of New Physics that could explain how our universe came to be the way it is.
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</p>
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</section>
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<section data-min-level="5">
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<hr>
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<h5>Resources</h5>
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<ul>
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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 data-min-level="10"><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 data-min-level="10"><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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</section>
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