[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.25,0:00:03.51,Default,,0000,0000,0000,,What is the Higgs?
Dialogue: 0,0:00:03.78,0:00:07.33,Default,,0000,0000,0000,,Since 1964 we've had this idea
Dialogue: 0,0:00:07.58,0:00:11.03,Default,,0000,0000,0000,,proposed by Englert, Brout and Higgs
Dialogue: 0,0:00:11.59,0:00:15.29,Default,,0000,0000,0000,,that empty space is like a medium
Dialogue: 0,0:00:16.12,0:00:19.58,Default,,0000,0000,0000,,and as particles travel through this medium
Dialogue: 0,0:00:19.78,0:00:21.75,Default,,0000,0000,0000,,some of them interact with it,
Dialogue: 0,0:00:21.80,0:00:23.91,Default,,0000,0000,0000,,some of them don't interact with it.
Dialogue: 0,0:00:24.12,0:00:26.89,Default,,0000,0000,0000,,The ones that do interact with this medium,
Dialogue: 0,0:00:26.98,0:00:28.67,Default,,0000,0000,0000,,they acquire masses,
Dialogue: 0,0:00:28.74,0:00:31.45,Default,,0000,0000,0000,,and the ones that pass through it without interacting,
Dialogue: 0,0:00:31.51,0:00:33.56,Default,,0000,0000,0000,,those are massless particles.
Dialogue: 0,0:00:34.06,0:00:36.42,Default,,0000,0000,0000,,Let me give you an analogy:
Dialogue: 0,0:00:36.42,0:00:39.98,Default,,0000,0000,0000,,imagine an infinite field of snow
Dialogue: 0,0:00:40.14,0:00:42.77,Default,,0000,0000,0000,,extending thoughout all of space,
Dialogue: 0,0:00:43.11,0:00:46.82,Default,,0000,0000,0000,,flat, featureless, going in all directions,
Dialogue: 0,0:00:47.47,0:00:49.56,Default,,0000,0000,0000,,maybe the middle of Siberia.
Dialogue: 0,0:00:50.22,0:00:52.26,Default,,0000,0000,0000,,Now imagine that you're trying to cross
Dialogue: 0,0:00:52.28,0:00:53.72,Default,,0000,0000,0000,,this field of snow.
Dialogue: 0,0:00:54.03,0:00:56.30,Default,,0000,0000,0000,,So maybe you're a skier,
Dialogue: 0,0:00:56.36,0:00:58.50,Default,,0000,0000,0000,,and you skim across the top,
Dialogue: 0,0:00:58.50,0:00:59.94,Default,,0000,0000,0000,,that's like a particle that
Dialogue: 0,0:00:59.94,0:01:02.29,Default,,0000,0000,0000,,does not interact with the Higgs field,
Dialogue: 0,0:01:02.29,0:01:05.87,Default,,0000,0000,0000,,it does not sink into the snow, it goes very fast.
Dialogue: 0,0:01:06.05,0:01:09.98,Default,,0000,0000,0000,,That's like a particle with no mass travelling at the speed of light.
Dialogue: 0,0:01:10.87,0:01:13.24,Default,,0000,0000,0000,,But maybe you've only got snow shoes,
Dialogue: 0,0:01:13.24,0:01:16.84,Default,,0000,0000,0000,,in that case you sink into the Higgs snow field,
Dialogue: 0,0:01:17.44,0:01:20.68,Default,,0000,0000,0000,,you've got less speed that the skier,
Dialogue: 0,0:01:20.77,0:01:23.01,Default,,0000,0000,0000,,less that the speed of light.
Dialogue: 0,0:01:23.07,0:01:25.53,Default,,0000,0000,0000,,That's like a particle with mass, because you are
Dialogue: 0,0:01:25.53,0:01:29.09,Default,,0000,0000,0000,,connecting, interacting, with that Higgs snow field.
Dialogue: 0,0:01:29.62,0:01:33.11,Default,,0000,0000,0000,,And then finally if you've just got boots on,
Dialogue: 0,0:01:33.16,0:01:35.77,Default,,0000,0000,0000,,then you you sink deeply into the snow,
Dialogue: 0,0:01:35.77,0:01:37.59,Default,,0000,0000,0000,,you go very very slowly,
Dialogue: 0,0:01:37.64,0:01:40.17,Default,,0000,0000,0000,,and that's like a particle with a big mass.
Dialogue: 0,0:01:40.51,0:01:44.59,Default,,0000,0000,0000,,So, think of this Higgs field as being
Dialogue: 0,0:01:44.59,0:01:47.47,Default,,0000,0000,0000,,like this universal field of snow.
Dialogue: 0,0:01:48.15,0:01:51.73,Default,,0000,0000,0000,,Now, where does the Higgs boson come in?
Dialogue: 0,0:01:52.26,0:01:55.19,Default,,0000,0000,0000,,We all know what snow is made out of, right.
Dialogue: 0,0:01:55.19,0:01:57.25,Default,,0000,0000,0000,,It's made out of snow flakes.
Dialogue: 0,0:01:57.44,0:02:01.92,Default,,0000,0000,0000,,In the same way this universal Higgs snow field,
Dialogue: 0,0:02:01.92,0:02:04.91,Default,,0000,0000,0000,,is made up out of little quanta,
Dialogue: 0,0:02:04.91,0:02:09.65,Default,,0000,0000,0000,,those quanta are like snowflakes, that's what we call the Higgs boson.
Dialogue: 0,0:02:13.08,0:02:16.89,Default,,0000,0000,0000,,The Higgs boson has this job of giving masses
Dialogue: 0,0:02:16.89,0:02:19.25,Default,,0000,0000,0000,,to all the other elementary particles.
Dialogue: 0,0:02:21.84,0:02:25.41,Default,,0000,0000,0000,,If you look at the basic equations
Dialogue: 0,0:02:25.41,0:02:29.63,Default,,0000,0000,0000,,of the Standard Model, as written on my T-shirt,
Dialogue: 0,0:02:30.31,0:02:33.01,Default,,0000,0000,0000,,they're very symmetric, that way in which
Dialogue: 0,0:02:33.20,0:02:35.68,Default,,0000,0000,0000,,all the different particles appear is the same.
Dialogue: 0,0:02:36.21,0:02:38.96,Default,,0000,0000,0000,,At least on the top two lines there is nothing
Dialogue: 0,0:02:39.03,0:02:42.89,Default,,0000,0000,0000,,to distinguish particles that have different masses for example.
Dialogue: 0,0:02:43.89,0:02:46.46,Default,,0000,0000,0000,,But this symmetry has to be broken,
Dialogue: 0,0:02:46.100,0:02:49.19,Default,,0000,0000,0000,,electrons are lighter than muons,
Dialogue: 0,0:02:49.32,0:02:51.32,Default,,0000,0000,0000,,the top quark is much much heavier
Dialogue: 0,0:02:51.35,0:02:53.66,Default,,0000,0000,0000,,than the quarks that make up everyday nuclei.
Dialogue: 0,0:02:54.03,0:02:57.68,Default,,0000,0000,0000,,So, the top two lines, the symmetric lines,
Dialogue: 0,0:02:57.77,0:02:59.35,Default,,0000,0000,0000,,cannot be all there is,
Dialogue: 0,0:02:59.44,0:03:02.48,Default,,0000,0000,0000,,there has to be something to discriminate,
Dialogue: 0,0:03:02.54,0:03:05.22,Default,,0000,0000,0000,,distinguish, between the different types of particle.
Dialogue: 0,0:03:05.82,0:03:07.85,Default,,0000,0000,0000,,And that's the job of the Higgs boson,
Dialogue: 0,0:03:07.92,0:03:11.08,Default,,0000,0000,0000,,that's the job of the two bottom lines.
Dialogue: 0,0:03:11.15,0:03:15.46,Default,,0000,0000,0000,,Depending on how those different types of quark
Dialogue: 0,0:03:15.56,0:03:17.76,Default,,0000,0000,0000,,or the electron and muon,
Dialogue: 0,0:03:17.81,0:03:22.84,Default,,0000,0000,0000,,depending on how they connect to that Higgs field, that Higgs boson,
Dialogue: 0,0:03:22.84,0:03:25.05,Default,,0000,0000,0000,,we believe they get different masses.
Dialogue: 0,0:03:25.14,0:03:27.97,Default,,0000,0000,0000,,The symmetry between these particles is broken.