Understanding the Higgs Particle

[michael879]

I just read this book on the Standard Model. It goes over most things very briefly and one thing it explained badly was the higgs particle. Why exactly does it give every other massive particle mass? The Higgs field from a single particle would be negligible from far away right? If we managed to create a Higgs particle would all the particles around it become more massive? Or are their virtual higgs particles everywhere?

 

[mjsd]

badly explained? mm... what level is this? you sure need some advanced physics to understand it.

 

[Haelfix]

Try wikipedia. Very roughly (and sloppily) the gist is that most particles should theoretically be massless. To escape this disaster, and to make progress on the electroweak side of things (which at the time there was growing evidence for), several people invoked and utilized the Higgs mechanism. Whereby several terms in the lagrangian (one from symmetry breaking, the other a pure massless gauge term) conspire to add up and unite in such a way that a single new mass term appears. Happily, people then identify these new mass terms with all the known particles and the standard model was born.

Of course this neccessarily requires that symmetry breaking term to be present (also called a Goldstone boson), and this was called the Higgs particle.

 

[michael879]

yea that's the part I understand. I understand the basic concept. What I don't really get is the mechanism by which the higgs particle gives the other particles mass. The way it was explained in the book is that because the field of the particle is everywhere in space (by quantum field theory), when it breaks symmetry it "drags" the particles it interacts with it and makes their fields oscillate, giving them mass. However particle fields arent uniform throughout space. Because of this my first reaction was that particles closer to a higgs particle would be more massive than ones farther away. Obviously this isn't true so I am curious what I did wrong.

 

[Haelfix]

Yea, its a little bit off to think too seriously about the 'dragging particles through space, causing friction --> causing mass'. Its right in a sense, but can lead to misleading intuition.

I prefer to see it mathematically. After you have exploited local gauge invariance, and spontaneously broken the symmetry, and with a convenient choice of gauge. You are simply left with a massive scalar (the higgs) and a massive gauge field (what we wanted to give mass too).

These are no different than any other particle, they just are what they are.

The intuition is in a sense just a mirage, as we are simply free to transform it away into something more familiar and banal. Essentially the degree of freedom of the Goldstone boson is transformed into extra polarization degrees of freedom for the now massive gauge field. This happens everywhere (as it must, by local gauge invariance)

Thats about as much as I can explain with words I think

 

[nickthrop101]

the particles react with the higgs field in a way that gives them mass

 

[Vanadium 50]

This one is only four years old.