# Is the higgs boson the mediator of the higgs field?

Gold Member
I'm a little confused about whether the higgs boson is the mediator of the higgs field. I haven't had a chance to study in depth the higgs field theory, but I have tried finding information from seemingly reliable sources and there are some apparent contradictions. I watched Leonard Susskinds lecture on the higgs boson, and he along with other sources have said that the higgs boson can be thought of as a dense region in the higgs field. Leonard susskind says that it is a particles exchange with another particle that he calls the "ziggs boson"; both absorbing and then reemitting the "ziggs" back into the condensate(higgs field?) that gives their mass. He then says the higgs boson is an excited state of the higgs field after the fact. This seems to imply that the higgs boson is not a mediator of the higgs field. I did read on fermilab's site saying that the higgs boson can interact with particles in more ways than the higgs field and in this sense the higgs boson can be thought of as a mediator of the higgs field. It was made clear that it's the higgs field that gives mass, so I'm not sure yo what extent the higgs boson mediates there. Finally, on the hyperphysics site here http://hyperphysics.phy-astr.gsu.edu/hbase/forces/higgs.html and some more popular science sites, the higgs boson is described as the mediator of the higgs field and giving mass. I really appreciate any help sorting out my confusion.

Homework Helper
Leonard Susskind ... with other sources ... seem to imply that the higgs boson is not a mediator of the higgs field.
Sounds to me like he did imply exactly that - but just went into details about how it happens.

fermilab's site saying that the higgs boson can ... be thought of as a mediator of the higgs field.
(my emphs)

hyperphysics ... and some more popular science sites, the higgs boson is described as the mediator of the higgs field and giving mass.

I think I see the problem.

Compare:

The particle associated with the electromagnetic field is the photon.
Photons mediate the electromagnetic interaction and may be thought of as mediators for electromagnetic field.

The particle associated with the Higgs field is the Higgs boson.
Higgs Bosons mediate the Higgs interaction which is what gives particles their mass.
They can be though of "mediators of the Higg's field" in this sense.

Susskind just described the Higgs interaction in more detail ... thinking of these particles "mediators" is something of a simplification for people who don't have the math.

That help?

1 person
Gold Member
The particle associated with the Higgs field is the Higgs boson.
Higgs Bosons mediate the Higgs interaction which is what gives particles their mass.
They can be though of "mediators of the Higg's field" in this sense.

Susskind just described the Higgs interaction in more detail ... thinking of these particles "mediators" is something of a simplification for people who don't have the math.

That help?

To some extent. I think what's throwing me off is Susskind's use of the "ziggs boson" as something completely different than the Higgs Boson. It seemed to me that it was the "ziggs" that is the "mediator" of the higgs interaction and that the higgs had no play in the particle acquiring mass. In Susskind's lecture, he goes on to say that it isn't really the higgs that gives mass, but the "ziggs".

Gold Member

OK, so that makes it more clear how the ziggs can give mass to a particle. I still don't see how the higgs boson plays a role. Unless Susskind is saying that particles interact with these dense regions of the condensate(higgs boson) which therefore acts as the mediator of the ziggs boson and higgs field which then give mass?

Homework Helper
Yeah, we may have to wait a bit for the theory to work itself out.
It's still at the esoteric math stage.

I'm a little confused about whether the higgs boson is the mediator of the higgs field. I watched Leonard Susskinds lecture on the higgs boson, and he along with other sources have said that the higgs boson can be thought of as a dense region in the higgs field. He then says the higgs boson is an excited state of the higgs field after the fact. This seems to imply that the higgs boson is not a mediator of the higgs field. I really appreciate any help sorting out my confusion.
It's more important to understand what's going on rather than the semantics of a particular word, but for the record, fields do not have "mediators", fields have excitations.

One can speak of a force having a mediator, meaning a particle that serves to transmit the force from one object to another. The photon mediates the electromagnetic force, the graviton (if it exists) mediates the gravitational force, the W and Z mediate the weak force, and the gluon mediates the strong (aka color) force. There is no Higgs force to mediate.

Leonard susskind says that it is a particles exchange with another particle that he calls the "ziggs boson"; both absorbing and then reemitting the "ziggs" back into the condensate(higgs field?) that gives their mass.
Susskind is just trying to be cute. Unfortunately, in trying to come up with fanciful ways to dance around the Higgs idea he's just causing more confusion. The blog that Simon cited is even worse - total crackpottery.

Gold Member
By Susskin's lecture, I thought that the ziggs boson is a goldstone boson... no wonder since he got it photonlike so massless... so it comes from fluctuations around the minimum of the higgs potential.
The higgs boson however,being massive, comes from fluctuations along the other possibility.
What I mean is that having the complex field F you can write it F=F1+i F2 but you can also write it as F=R exp[iB] as "polar coords". The goldstone boson then would come from fluctuations on B and the higgs from R.

So i hope I helped in your understanting. In SM from all I know, you can get rid of the goldstone bosons -B- by working on the unitary gauge, and giving some extra degrees of freedom to your W bosons.

Gold Member
It's more important to understand what's going on rather than the semantics of a particular word, but for the record, fields do not have "mediators", fields have excitations.

One can speak of a force having a mediator, meaning a particle that serves to transmit the force from one object to another. The photon mediates the electromagnetic force, the graviton (if it exists) mediates the gravitational force, the W and Z mediate the weak force, and the gluon mediates the strong (aka color) force. There is no Higgs force to mediate.

Susskind is just trying to be cute. Unfortunately, in trying to come up with fanciful ways to dance around the Higgs idea he's just causing more confusion. The blog that Simon cited is even worse - total crackpottery.

OK, if that's the case then my question really is, does the higgs boson plays any role in a particles interaction with the higgs field? Or what role if any does the higgs boson play in a particle attaining mass? As I said in one of my other posts, the higgs boson seems to be something after the fact.

Staff Emeritus
This is always going to be confusing if you try to run first before learning how to walk. So let's probe this a bit more and see if you already understood OTHER things first.

Let's try the electromagnetic interaction. Have you already understood the QFT picture of this interaction that is mediated via virtual photons?

Zz.

Gold Member
This is always going to be confusing if you try to run first before learning how to walk. So let's probe this a bit more and see if you already understood OTHER things first.

Let's try the electromagnetic interaction. Have you already understood the QFT picture of this interaction that is mediated via virtual photons?

Zz.

I am aware of that, yes.

Staff Emeritus
I am aware of that, yes.

OK then. If you know that, then you should be familiar with the concept that the virtual photons are the quantum field excitations of the EM field, no?

Zz.

Gold Member
OK then. If you know that, then you should be familiar with the concept that the virtual photons are the quantum field excitations of the EM field, no?

Zz.

I didn't know the details of what that meant, so no I didn't know that virtual photons are quantum field excitations of the EM field.

Is this what the Higgs Boson is but for the Higgs field?

OK, if that's the case then my question really is, does the higgs boson plays any role in a particles interaction with the higgs field? Or what role if any does the higgs boson play in a particle attaining mass? As I said in one of my other posts, the higgs boson seems to be something after the fact.
You got it right. The Higgs field allows particles to have mass, while the Higgs boson plays no direct role in that. You can think of it as a side effect, but an important one, one that can be detected. Finding the Higgs boson is only the beginning, the LHC will spend the next 10-20 years exploring its properties.

Staff Emeritus
I didn't know the details of what that meant, so no I didn't know that virtual photons are quantum field excitations of the EM field.

Is this what the Higgs Boson is but for the Higgs field?

In a naive way, yes, that is what the Higgs is with respect to the Higgs field, but in the sense that the collisions that we created caused the Higgs make its existence known briefly so that we can infer about the Higgs field.

Zz.

Gold Member
In a naive way, yes, that is what the Higgs is with respect to the Higgs field, but in the sense that the collisions that we created caused the Higgs make its existence known briefly so that we can infer about the Higgs field.

Zz.

OK, so by making these collisions, we excited the higgs field which created the higgs bosons which I see is important in confirming the existence of the higgs field. But as in the hyperphysics link I posted in the OP, it says, "The theories attribute the symmetry-breaking to a field called the Higgs field, and it requires a new boson, the Higgs boson, to mediate it." This sounds like for a particle to acquire mass, it must interact with a higgs for the higgs field. In the same way, I assume that virtual photons are necessary for a charged particles interaction with an EM field. But as in the susskind lecture, and post #14, it sounds like the boson is merely a side effect.

Here's a quote from a livescience article: "In physics, when particles interact with fields, the interaction must be mediated by a particle. Interactions with the electromagnetic (EM) field, for example, are mediated by photons, or particles of light. When a negatively charged electron is pulled by the EM field toward a positively charged proton, the electron experiences the EM field by absorbing and emitting a constant stream of "virtual photons" â€” photons that momentarily pop in and out of existence just for the purpose of mediating the particle-field interaction. Furthermore, when the EM field is "excited," meaning its energy is flared up in a certain spot, that flare-up is, itself, a photon â€” a real one in that case.

Along the same lines, the Higgs particle mediates interactions with the Higgs field, and is itself an excitation of the Higgs field. Particles are thought to trudge through the Higgs field (thereby acquiring mass) by exchanging virtual Higgs particles with it." http://www.livescience.com/21400-what-is-the-higgs-boson-god-particle-explained.html

So here, now it's "virtual Higgs particles" that mediate the interaction. I feel like I'm sort of going in circles here.

I feel like I'm sort of going in circles here.
I feel like you are too!

Here's a quote from a livescience article:

Gold Member

Perhaps that's what's contributing to a lot of my confusion then! I can think of the higgs field as being responsible for giving mass and the higgs boson as being a side effect. Also, that the higgs boson is simply an excitation of the higgs field. I guess the question really is, does the higgs boson do anything? I mean, does it do anything to other particles?

I guess the question really is, does the higgs boson do anything? I mean, does it do anything to other particles?
The Higgs field is a permanent feature of the vacuum, and can therefore have a permanent effect on particles. By comparison the Higgs boson is very short-lived, predicted to live about 10-22 secs, and therefore any effect it has must be brief. Like other particles it collides with other particles, decays into other particles, etc. All we can measure are its decay probabilities and decay rates.

But these reflect the properties of the Higgs field. For example the fact that the mass of a fermion is determined by how strongly it interacts with the Higgs field will be reflected in a property of the Higgs boson, namely the boson must interact more strongly with the heavier fermions, proportionally to their mass.

1 person
Gold Member
The Higgs field is a permanent feature of the vacuum, and can therefore have a permanent effect on particles. By comparison the Higgs boson is very short-lived, predicted to live about 10-22 secs, and therefore any effect it has must be brief. Like other particles it collides with other particles, decays into other particles, etc. All we can measure are its decay probabilities and decay rates.

But these reflect the properties of the Higgs field. For example the fact that the mass of a fermion is determined by how strongly it interacts with the Higgs field will be reflected in a property of the Higgs boson, namely the boson must interact more strongly with the heavier fermions, proportionally to their mass.

That's what I would have expected. When it comes to the higgs mechanism then, we don't need to consider the action of the higgs boson. It seems that popular press as created a confusion in portraying the higgs as an actor in the process. With that behind me, what particle exchange does occur that allows some particle to interact with the higgs field?

Gold Member
With that behind me, what particle exchange does occur that allows some particle to interact with the higgs field?

Would it actually be the "ziggs boson" that susskind was referring to?

what particle exchange does occur that allows some particle to interact with the higgs field?
None, there is no particle exchange involved. As we said earlier (post #7), the idea that particle exchange "mediates" an interaction does not apply to the interaction between a particle and a field. The particle simply interacts with the field, without any help! We listed in #7 the cases in which mediators are involved.

The mass term for a fermion is simply proportional to the value v of the Higgs field, the constant of proportionality being different for each type of fermion.

1 person
Gold Member
None, there is no particle exchange involved. As we said earlier (post #7), the idea that particle exchange "mediates" an interaction does not apply to the interaction between a particle and a field. The particle simply interacts with the field, without any help! We listed in #7 the cases in which mediators are involved.

The mass term for a fermion is simply proportional to the value v of the Higgs field, the constant of proportionality being different for each type of fermion.

Oh that's right! A particle interacts with the higgs field and that's it since the higgs field is not a force. The higgs boson is merely excitations in the higgs field, so it's just a side effect. I think this is starting to clear up for me now!

Gold Member
you should look at the mathematical derivation of the higgs mechanism an interpret it...there you see everything happening and you can know what's going on and where.

Gold Member
you should look at the mathematical derivation of the higgs mechanism an interpret it...there you see everything happening and you can know what's going on and where.

I agree, that would be the best way to understand it. I would appreciate any recommendations for any textbooks on particle physics if anyone knows of any. Thanks!

Gold Member
I agree, that would be the best way to understand it. I would appreciate any recommendations for any textbooks on particle physics if anyone knows of any. Thanks!

Any book that deals with Standard Model in advanced (graduate) level, will surely have what you ask. This paper
http://arxiv.org/pdf/1312.5672v1.pdf
also was the last one I read recently, and I find it nice.
But to be honest, I have never found a textbook that does the whole calculations, the most you need to do by your own...

Gold Member
Any book that deals with Standard Model in advanced (graduate) level, will surely have what you ask. This paper
http://arxiv.org/pdf/1312.5672v1.pdf
also was the last one I read recently, and I find it nice.
But to be honest, I have never found a textbook that does the whole calculations, the most you need to do by your own...

Thanks for that! I'll check it out.

StandardsGuy
I feel like you are too!

Then what is the truth (in your opinion)?

Homework Helper
StandardsGuy said:
Bil_K said:
Then what is the truth (in your opinion)?
Knowing falsehood does not imply knowing the truth.
(... and physical reality is not usually a matter of opinion.)

However - we can talk about how an article misrepresents a physical model from knowledge of that model.
I'll have a go - Bill K will, probably, fill in the bits I miss. I suspect the objections go something like this:

The quote in question is from "Livescience" - a pop-science news-site not known for being scientifically accurate. To be fair on the authors, they are trying to get some subtle points of field theory across to a target audience that struggles with high-school maths. This is not easy, we can't really expect them to get everything just right.

I'll break the quote up into individual points:

"In physics, when particles interact with fields, the interaction must be mediated by a particle.

... or, indeed, when they interact with each other, or, at all.
The statement is stronger than I'd make it but it is probably fair.

Interactions with the electromagnetic (EM) field, for example, are mediated by photons, or particles of light.

It is the interaction that is "mediated" by the virtual particle, not the field.

When a negatively charged electron is pulled by the EM field toward a positively charged proton, the electron experiences the EM field by absorbing and emitting a constant stream of "virtual photons",
The picture you get here is that electrons are firing and getting hit by a constant stream of photons - this is not correct.

Compare with:
http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html
... which gives you a better idea how virtual particles mediate forces.

photons that momentarily pop in and out of existence just for the purpose of mediating the particle-field interaction.

That's quite iffy - how do these virtual photons know to "pop" into existence at just the right moment to mediate the field? (Covered in previous link.)

Furthermore, when the EM field is "excited," meaning its energy is flared up in a certain spot, that flare-up is, itself, a photon, a real one in that case.

This is so confused it is hard to know where to start: see the following -
http://profmattstrassler.com/articl...ysics-basics/virtual-particles-what-are-they/

... and all this is before you get close to thinking about Higgs.

But like I said before, the authors are trying to explain in a single chatty sentence something that actually requires many paragraphs - and, even then, it's incomplete. Of course they got it wrong!
They got it cringe-worthily wrong.
How could they not?

StandardsGuy
Thanks. I agree that we can't expect the authors to get everything exactly right. Somebody had to tell them those things. Oversimplification is highly probable, but I think they did an amazingly good job. In your first link, the authors admitted that they used gross oversimplification. In the second one they said virtual particle'' is a problematic term. I found the first one a little ad-hoc. They seemed to have a "two-worlds" theory with a "position-space universe" and a "momentum-space universe." Still, I appreciate the links. I was, however, more interested in the Higgs mechanism.

Homework Helper
Oversimplification is highly probable, but I think they did an amazingly good job.
As a basis for learning more about the standard model and the Higgs mechanism (the context in which is was quoted) - not really. As something to give a lay reader a sense of exciting things happening - better. The second is what it was written for, after all.

Both links are oversimplified - I can give you a link to the actual, unsimplified, stuff if you like: how's your maths?

Note: If those are "gross simplifications" - where does that leave the quoted passage, that was the context, which is even more oversimplified still?

In the second one they said virtual particle'' is a problematic term.
... and they explained why it is problematic and addressed the problem in a way that illustrated why the associated part of the LiveScience article was "baloney"... in an accessible way.

I found the first one a little ad-hoc. They seemed to have a "two-worlds" theory with a "position-space universe" and a "momentum-space universe."
The position and momentum spaces are fourier transforms of each other - they describe the same World.

Still, I appreciate the links. I was, however, more interested in the Higgs mechanism.
Well, when you asked the question, you wrote that you were interested in the truth by the opinion of Bill_K. I hoped that I'd interpreted your intention correctly... you asked about a passage Bill_K had criticized which was quoted from a LiveScience article linked to earlier.

The quoted passage made no reference to the Higgs mechanism.
phy-infinite quoted it.

Please understand: In order to get a good idea about the Higgs mechanism, the interested student really needs a better picture of the standard model than the LiveScience article gives you.

Perhaps something like:
Bernstein J. Spontaneous symmetry breaking, gauge theories, the Higgs mechanism and all that (1974) Rev Mod Phys.

Maybe:
Organtini G. Unveiling the Higgs mechanism to students Eur. J. Phys. 33 (2012) 1397-1406

There are no end of lecture summaries:
i.e. http://www.physics.buffalo.edu/pasi/HiggsbosonLecture1.pdf

Basically you'll need to pick one that is suitable to your education.
Enjoy.