WEBVTT

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You've probably heard of electrons and protons,

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the building block particles that make up atoms.

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But there are all kinds of other particles in the universe,

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and we have a pretty good idea of what they are and how they interact.

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But even our best theories struggle when it comes to big nasty questions.

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Like, where does mass come from?

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And what is dark matter made of?

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There may be a theory that can answer these questions at a stroke.

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It's elegant, mathematically speaking, but is it true?

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It's called "Super Symmetry".

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If you wanted to explain why all stuff in the universe behaves the way it does,

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you could do a lot worse than the so-called "Standard Model".

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Developed in the 1960's and 70's,

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it categorises all fundemental particles as either "leptons", like electrons,

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"quarks", the building blocks of protons and neutrons,

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or "force carriers", like photons, which transmit electric and magnetic force.

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The Standard Model is a triumph of modern physics,

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every particle the theory predicts has been observed in experiments,

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except for one.


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The Higgs boson, a force carrrier thought to give other particles the property of mass,

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has so far eluded direct detection.

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And what's worse, experiments suggest that if the Higgs boson exists,

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it would likely be way lighter than the simple Standard Model predicts.

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But all is not lost.

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Physicists can get around this problem with a little mathematical tweaking.

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Think of the Standard Model as an old school hi-fi stereo system,

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and the variables in the theory are like the knobs on the amplifier.

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To get the sound you want you can twiddle the various bass, mid and high levels,

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tweaking by tiny amounts until it sounds just right.

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That's fine for listening to [Led] Zeppelin records, but instead of just 3 knobs

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the Standard Model has almost 20.

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How would you know how to set them all?

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With no real physical reason for turning one know one way, and another the other way,

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it's all very arbitrary, and not how we'd like to think the universe actually works.

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It would be nice if there were a more elegant solution.

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As it turns out the theory of Super Symmetry allows the mass of the Higgs boson

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to be in the right range without fine tuning the math.

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It does so by introducing a whole new cast of particles to pair up with the ones

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we already know about.

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These super partners are like bizarre world versions of the Standard Model particles only more massive.

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And not only do they interact to solve the Higgs mass problem,

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they also provide a plausible explanation for dark matter.

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The mysterious mass that makes up the bulk of the universe.

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The problem is none of these super particles have been detected yet.

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Even by the Large Hadron Collider, which many thought would have found them by now.

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This doesn't mean Super Symmetry isn't true, but it leaves the door open

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for all kinds of other theories, from messier versions of the Standard Model

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to more exotic theories envoking extra dimensions.

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So far, with no Higgs boson and no super partners, the chance of having

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a simple theory to explain everything seems to be getting smaller.

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But that may be ok.

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After all, there's nothing that says the physical world has to follow elegant mathematical rules.

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As much as we might hate to admit it, it could be that even at its most fundamental levels,

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reality is just messy.