Higgs boson

[questionposter]

The Higgs is a scalar boson and not vector boson. It cannot be understood in terms of a connection and so is not directly related to gauge symmetry, which is really the origin of the forces.

 

However, the Higgs can be understood in terms of a superconnection in the sense of Quillen.

 

A Higg's boson is what's suppose to be carrying mass in the fundamental mass particles right? Well how can a force carry mass? Plus, isn't there already some other type of boson to describe how the force of gravity is carried like a W boson or Z boson or something like that?

[ajb]

A Higg's boson is what's suppose to be carrying mass in the fundamental mass particles right?

 

The Higgs is believed to be reasonable for the generation of mass. This is the mass of the [math]W^{\pm}[/math] and [math]Z^{0}[/math] bosons as well as the mass of the leptons.

 

 

 

Plus, isn't there already some other type of boson to describe how the force of gravity is carried like a W boson or Z boson or something like that?

 

Gravitons would be the quanta associated with gravity. These would be spin-2 and massless.

[Amr Morsi]

A question: Do Higgs bosons mediate interactions in Color (strong) Force, taking into account that Leptons don't experience this type of force?

 

But, I am sure of something, which is: As long as Color Charge has its own unique type away from the Electric Charge, then Higgs Bosons can't be involved in the strong force, unless leptons can be proven to consist of certain quark-composition that makes its interaction in Color Force is null, or do have small color charge, because at that instance the Higgs boson will have a color charge, no doubt. And, since this suppose is BELIEVED to be wrong, then Higgs Boson can't contribute in Strong Force. A philosophical discussion.

 

A good point: mediators are mostly believed to interact, themselves, by the force they mediate, I don't know how. So, do Higgs bosons are believed to interact with any force, especially the weak force (and so they do have an electric charge and interacting with electromagnetic force {Electro-Weak})?

 

Do Higgs Boson have Electric Charge? Note that they breaks the symmetry in/of a charge medium.

[ajb]

We have models in which the Higgs is neutral and we have various charged Higgs models, which I believe is needed in supersymmetric models. There are models in which the Higgs is also coloured, but I know nothing about these.

[Amr Morsi]

The following may be true: "If Higgs has color charge, then it will consequently have electric charge and will be used to unify (and most probably: alone) the Standard Model".

 

But, a question: "Does the symmetry ALWAYS get broken in Electro-Weak Interaction?".

[ajb]

But, a question: "Does the symmetry ALWAYS get broken in Electro-Weak Interaction?".

 

You need a mechanism that provides the mass for the gauge bosons, but keeps the renormalisability. The key point is that gauge symmetry cannot be an exact symmetry if the gauge bosons are massive.

 

The most popular model is to use the Higgs-Kibble mechanism, with various different details for the Higgs field, say neutral or charged. The other well studied mechanism is technicolor where the symmetry is dynamically broken by adding new gauge interactions. The basic idea is to follow what is known bout QCD.

 

There maybe other models out there, but variants of the Higgs or technicolor seem by far the most popular and studied.

[Amr Morsi]

I don't think that it is a force, ajb ..... a fifth (fourth) force? Or, do you mean that it is the mediator of Electro-Weak? Can't be. Then, consequently it is a particle and even if virtual, its effect is sensed which is an intermediate stage in Nuclear Weak Force in particular, or NSF in addition.

 

Anyway Higgs effect is recorded, like quarks' one. And, I do stress on this, from my side. But, it is not a must for electromagnetism ... what do you think?

[ajb]

Or, do you mean that it is the mediator of Electro-Weak?

 

The higgs is certainly not the mediator of the electroweak nor the broken electromagnetic + weak.

 

 

Then, consequently it is a particle and even if virtual, its effect is sensed which is an intermediate stage in Nuclear Weak Force in particular, or NSF in addition.

 

You mean mass, as we have a duality between fields and particles. Subject to conservation laws etc all matter can appear as internal loops in Feynman diagrams. Not that I would want to say that matter also mediates forces they do contribute.

 

 

Anyway Higgs effect is recorded, like quarks' one. And, I do stress on this, from my side. But, it is not a must for electromagnetism ... what do you think?

 

I am not sure what you are saying. The electromagnetic sector is not broken, the photon remains massless.

[Amr Morsi]

This is absolutely what I want to stress upon, ajb. It can be an important tool in next discussion.

[36grit]

This maybe a dumb queastion but here it is anyway, Is it possible, or is there any models, that would have the Higgs interacting with all four forces?

[ajb]

This maybe a dumb queastion but here it is anyway, Is it possible, or is there any models, that would have the Higgs interacting with all four forces?

 

The Higgs is one way of giving mass to all massive particles, not just the W's and Z. That is the Higgs-Kibble mechanism could be responsible for the mass for all leptons. So, in this respect the Higgs interacts with all four forces. For example the Higgs does couple to quarks and therefore it does "interact" with the strong force. Though the mass of the hardrons is largely not due to the Higgs, but due to the binding energy.

 

Also the Higgs will carry energy momentum and thus would act as a source of gravity. However, the gravitational interaction will be swamped by the other forces in experiments based at CERN. Unless we have large extra dimensions or something else exotic going on.

[Amr Morsi]

The Higgs is one way of giving mass to all massive particles, not just the W's and Z. That is the Higgs-Kibble mechanism could be responsible for the mass for all leptons. So, in this respect the Higgs interacts with all four forces.

 

Then do it is the origin ..... or a like .......... ajb. Can you make a research in this, to cut it out? GO ahead buddy.

 

But, is it a mechanism also for electrons-positrons interaction for example? I am just trying to open a way or even a door.

[ajb]

Then do it is the origin ..... or a like .......... ajb. Can you make a research in this, to cut it out? GO ahead buddy.

 

The Higgs-Kibble mechanism will be covered in most quantum field theory books. However, they often just look at giving mass to the gauge bosons or a scalar field. I am sure there is a book with the details in, but this is not really my area of expertise. I am unable to recall details off the top of my head. However, if I recall right one uses a Yukawa coupling between the massless fermions and the Higgs field. This then generates a mass term.

 

 

But, is it a mechanism also for electrons-positrons interaction for example? I am just trying to open a way or even a door.

 

Can the Higgs appear as an internal line in a Feynman diagram describing electron-positron scatterings?

 

You can have Higgs decay into a fermion and antifermion. So I see no immediate reason why you cannot have the Higgs as an internal line in electron-positron interactions. I imagine they are suppressed as compared to the photon exchange.

 

We would need to talk to a real particle physicist to get at the guts of this.

[Dekan]

As we now know, the latest data from the LHC's ATLAS and CMS dectectors, excludes a Higg's mass of between 145 and 466 GEV. Higgs might be in the lower range 115 - 145 GEV. But this range seems difficult to work in. So a final verdict may be delayed.

 

Suppose the verdict is - there's no trace of Higgs. Would that mean the end of the Higgs concept. Or just that the LHC is inadequate to detect such a radical particle.

 

A particle which endows mass, might possess radical properties. Possibly, higher Dimensional properties. Eg, a (non-time related) 4th Dimensional extension. Would such a 4-D extension be visible to the LHC? The LHC is, after all, an apparatus built in only 3 Dimensions.

 

So perhaps the 3-D "eye" of the LHC, can't detect the Higgs - just as the 2-D eye of a "Flatlander", couldn't detect a 3-D object such as an atom?

[Amr Morsi]

Suppose the verdict is - there's no trace of Higgs. Would that mean the end of the Higgs concept. Or just that the LHC is inadequate to detect such a radical particle.

 

A great but destructive approach / question.

 

"A concept that satisfies all facts with nothing contradicting it [including unjustification delimas], is a satisfier, but not mainly THE solution" ...... A good rule (if correct to you) in the science of "Modelling".

 

I mean: Is there something that says that Higgs is the only satisfying concept - i.e. the solution? If yes then GET SURE that it is the correct one and that it will never end up.

 

But, we must make checks to discriminate the situation, i.e. to confirm exactly the known model. I am just commenting.

[Dave World]

There are times that I feel that I am having a conversation with a random text generator.

 

That bit of levity is truly appreciated by this Lepton.

 

 

 

Something else. Stay tuned.

 

I hesitate to intrude with a simple question, but here it is. If the Higgs boson is neither a particle nor a force, might it be the interface between the two? Hmm. A conundrum, isn't it?

Edited August 29, 2011 by Dave World

[ajb]

I hesitate to intrude with a simple question, but here it is. If the Higgs boson is neither a particle nor a force, might it be the interface between the two? Hmm. A conundrum, isn't it?

 

Quantum field theory does not really make a distinction between particles and fields. Particles have a field nature and fields have a particle nature. Though the usual formulation is to take the fields as fundamental and the particles as a derived notion.

 

So I don't really understand what you are getting at.

 

My question relies on the assertion that matter is made of fermions and forces are made of bosons (very loosely). The statistics seem to be important rather than the field or particle nature of stuff.

[Dave World]

I'm beginning to understand. Thanks.

[Mystery111]

I guess this is rather a philosophical question than a real physics/mathematics question.

 

If we assert that fundamental matter particles are always fermions and that forces are always mediated by bosons, or at least within the standard model, then should the Higgs be considered as matter or as a force?

 

My own through is that it is really neither and should be dealt with carefully when trying to assert matter <-> fermions and forces <-> bosons.

 

Then when we introduce supersymmetry the situation is even more mixed up, but lets not get ahead of ourselves.

 

So, do you think of the Higgs as matter or as a force, or as something else?

 

You can't assert this. Fundamental particles are not just fermionic, they can be bosonic. You can't divide a photon any more than you can divide a quark. Also, if forces where only explainable in terms of fermion fields, then how does one explain the photon carrying the electromagnetic interaction? Higgs is a particle which carries the mass charge to other particles. The charges are the coefficients of the Lie algebra of the locally gauged group. The fact the Higgs is a boson, does not get tied to just one being part of a field or a force carrier. There are forces inherent in all fields, as they contain momentum. A higgs boson though also is part of the higgs field - it's field permeates all space and time. Interestingly though, it only couples to a very small amount of matter in our universe, either a little over or just a little less than just 1% of all matter in the universe.

Edited August 29, 2011 by Mystery111

[ajb]

You can't assert this. Fundamental particles are not just fermionic, they can be bosonic.

 

I think you have misunderstood what my question is about. Fundamental particle can indeed be fermionic or bosonic.

 

The standard model tells us that matter, that is leptons and quarks are fermions as where forces have bosonic quanta, for example the quanta of the electromagnetic field is the photon.

 

 

You can't divide a photon any more than you can divide a quark.

 

Ok, so there is to date no experimental evidence to suggest any substructure to the photon or quarks.

 

 

 

A higgs boson though also is part of the higgs field - it's field permeates all space and time. Interestingly though, it only couples to a very small amount of matter in our universe, either a little over or just a little less than just 1% of all matter in the universe.

 

Most of the mass of "composite stuff" is not due to the Higgs, sure.

[Mystery111]

 

If we assert that fundamental matter particles are always fermions and that forces are always mediated by bosons, or at least within the standard model, then should the Higgs be considered as matter or as a force?

 

 

Right ok, you seem to be saying that the forces are exchanged by bosons specifically, obviously those being the gluon for the strong, photon for the EM, W and Z bosons for the weak force, and of course the graviton for the gravitational force. Ok... your question would have been a bit clearer if you had said:

 

''If we assert that fundamental matter particles are always fermions and that forces are always mediated by fundamental bosons''

 

 

That way it wouldn't have looked as though you were setting the term fundamental specifically to any one family. My fault though. I should have been more vigilant.

[Dave World]

Please recommend to me a "101" level textbook on the subject of particle physics. - dw

 

"I hear and I forget. I see and I remember. I do and I understand" - Confucius

[ajb]

I assume you know some quantum mechanics and relativity? If so then...

 

Das and Ferbel. Introduction to nuclear and particle physics, World Scientific Publishing Company; 2nd edition (December 23, 2003).

 

Griffiths. Introduction to Elementary Particles, Wiley-VCH; 2nd edition (October 21, 2008).

 

Neither of these will give you the necessary quantum field theory to really understand what is going on. But that can wait...

Edited August 30, 2011 by ajb

[Mystery111]

Apparently a growing number of scientists have been reported recently admitting that the standard model seems more likely now not to have the Higgs Mechanism. Has anyone read this? I have a link if wanted.

 

ajb

 

You said ''Particles have a field nature and fields have a particle nature.''

 

I was wondering if you agreed that initially the aether field could have been attributed to the former example here. Yet in a sense, the aether is replaced by the quantum field where the wave nature of particle is a distortion as a propogation of the field - the momentum of the field described by a wave. When a detector fires, some kind of collapse in the wave function [math]\int |\psi|^2[/math], there is by experimentation the appearance of a single particle form. So the idea of the wave form as a momentum of the field propogating as a wave was initially mistaken as some kind of... ''homogeneous'' physical medium. But I ask, what is a quantum field but a medium itself for a distortion of that field? What is the physical difference? I don't believe there is one. Would you agree?

[timo]

Apparently a growing number of scientists have been reported recently admitting that the standard model seems more likely now not to have the Higgs Mechanism. Has anyone read this? I have a link if wanted.

The Standard Model contains the Higgs boson - by definition. Whether what we currently call the Standard Model correctly describes nature, and in that sense whether the Higgs boson exists in nature, is another question that is still open. It is no new idea that the Higgs boson may not exist, and people stating that this possibility might in fact be the most exciting result of LHC is no news (it has been a standard statement in particle physics ~5 years ago, and probably way before then). I am not aware that much about this has changed since then. I remotely heard that LHC recently excluded some values for the possible mass of the Higgs boson. But if I remember correctly then these were ranges in which no one really expected the Higgs boson to be found in, anyways (although technically they would have been possible). Is it this exclusion of a mass range that you are referring to?