WEBVTT

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What is the Higgs?

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Since 1964 we've had this idea

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proposed by Englert, Brout and Higgs

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that empty space is like a medium

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and as particles travel through this medium

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some of them interact with it,

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some of them don't interact with it,

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The ones that do interact with this medium,

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they acquire masses,

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and the ones that pass through it without interacting,

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those are massless particles.

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Let me give you an analogy:

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imagine an infinite field of snow

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extending thoughout all of space,

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flat, featureless, going in all directions,

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maybe the middle of Siberia.

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Now imagine that you're trying to cross

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this field of snow.

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So maybe you're a skier,

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and you skim across the top,

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that's like a particle that a particle that

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does not interact with the Higgs field,

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it does not sink into the snow, it goes very fast,

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that's like a particle with no mass travelling at the speed of light.

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But maybe you've only got snw shoes,

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in that case you sink into the Higgs snow field,

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you've got less speed that the skier,

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less that the speed of light,

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that's like a particle with mass, because you are

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connecting, interacting, with that Higgs snow field.

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And then finally if you've just got boots on,

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then you you sink deeply into the snow,

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you go very very slowly,

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and that's like a particle with a big mass.

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So, think of this Higgs field as being

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like this universal field of snow.

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Now, where does the Higgs boson come in?

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We all know what snow is made out of.

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it's made out of snow flakes.

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In the same way this universal Higgs snow fields,

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is made up out of little quanta,

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those quanta are like snowflakes, that's what we call the Higgs boson.

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The Higgs boson has this job of giving masses

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to all the other elementary particles.

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If you look at the basic equations

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of the Standard Model, as written on my T-shirt,

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they're very symmetric, that way in which

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all the different particles appear is the the same.

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At least on the top two lines there're nothing

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to distinguish particles that have different masses for eaxample.

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But this symmetry has to be broken,

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electrons are lighter than muons,

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the top quark is much much heavier

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than the quarks that make up everyday nuclei.

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So, the top two lines, the symmetric lines,

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cannot be all there is,

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there has to be something to discriminate,

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to distinguish, between the different types of particle.

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And that's the job of the Higgs boson,

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that's the job of the two bottom lines.

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Depending on how those different types of quark

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or the electron and muon,

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depending on how they connect to that Higgs field,

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that Higgs boson,

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we believe they get different masses.

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The symmetry between these particles is broken.