WEBVTT

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If you've had any interested in physics at all you've heard about a thing called the

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Higgs boson.

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But just what is it then why is it interesting?

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In 1964 a physicist by the name of Peter Higgs

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took some ideas that were floating around at the time,

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added an insight or two of his own, and proposed that there was an energy field

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that permeated the entire universe.

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This energy field is now called the "Higgs field."

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The reason he proposed this field was that nobody understood why some

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subatomic particles had a great deal of mass

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while others had little and some had none at all!

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The energy field that Higgs proposed would interact

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with the sub-atomic particles and give them their mass. Very massive particles

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would interact a lot of the field while massless particles wouldn't interact at all.

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To better understand the idea, we can use the analogy of water and swimmers.

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In our analogy the water serves the role

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of the Higgs field.

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A barracuda, being supremely streamlined, interacts only slightly with

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the field and can move through it very easily.

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The barracuda would then be similar to a low-mass particle.

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In contrast, my buddy Eddie, no stranger to doughnuts

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can only move very slowly through the water.

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In our analogy, Eddie is a massive particle made massive by interacting a lot with

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the water.

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The lightest of the familiar subatomic particles is the electron, while in the subatomic

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world the king of mass is the top quark.

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It weighs about as much as an entire atom of gold,

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about three hundred and fifty thousand times more than the electron!

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I'd like to stress that we believe the top quark is not more massive because

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it's bigger. It's not!

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In fact, we believe that both the top quark and the electron are exactly the same size!

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Indeed, they both have zero size!

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The top quark is more massive than the electron simply because it interacts

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more with the Higgs field. Actually,

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if the Higgs field didn't exist,

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neither of these particles would have any mass at all!

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Now, in the press

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you don't hear about the Higgs field but rather the Higgs boson.

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How are these two things related?

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The Higgs boson is the smallest bit of the Higgs field.

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To understand how that works we should again return to water.

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Everyone knows what water is.

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If you're immersed in it you know that water is everywhere. It's a continuous medium

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and there are no holes in it.

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We also know that water is made of molecules - specifically H20.

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If you hold these two ideas in your head with the realization that water consists

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of countless individual molecules you can now begin to appreciate

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the Higgs boson.

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The Higgs field that gives subatomic particles their mass is made of countless individual

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Higgs bosons, just like water is made of individual molecules.

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You should keep in mind that the Higgs boson hasn't been discovered yet, and

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what I'm describing is simply the most popular idea as to why subatomic

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particles have the masses that they do.

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As I speak

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my colleagues and I are studying data taken at huge particle accelerators to see if

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this idea is true.

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Stay tuned!

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