# Will LHC season 2 tell us more about the Higgs Field?

1. Jun 3, 2015

### Michel_vdg

The data from the previous LHC season has indicated that the Higgs is sufficiently heavy enough to suggest that the Higgs Field is meta-stable (False Vacuum) with the potential of an another minimum with lower energies (True Vacuum).

So the question is if the second season of the LHC will tell us more about the Higgs Field itself, giving some more insight on its properties; and perhaps even provide a prediction for at what energies one could expect a decay towards the True Vacuum, indicating a region were the vertical tip-over-line is situated?

2. Jun 3, 2015

### Orodruin

Staff Emeritus
This assumes that there is nothing else than the Standard Model. A pretty boring scenario which we also have strong reason to doubt.

Yes, the new run of the LHC will indeed provide us more knowledge about the Higgs field and its properties - and hopefully even more than that.

3. Jun 3, 2015

### Michel_vdg

The LHC focuses on particle creation-discovery and its properties ... so lots of posibilies there to go beyond the Standard Model.

But how can a new property-deviation be assigned to either the particle or to the field?

For the magnetic field it is easy, as it is located around a particular point in space and spreads out ... but the Higgs Field is everywhere.

4. Jun 3, 2015

### Orodruin

Staff Emeritus
Yes, I am fully aware of that. What I am saying is that the current vacuum being a metastable one is predicated on there being nothing apart from the Standard Model.

The magnetic field is also everywhere. It may have an average value near zero, but the field itself is there. In fact, all fields are everywhere. What makes the Higgs special is that it is a scalar field and therefore can have a vacuum expectation value which does not break Lorentz invariance.

5. Jun 3, 2015

### Michel_vdg

Alright, that makes sense.

The magnetic filed lines don't tell us anything about the magnetic field itself, they tell us only something about the matter that generates them and the ripples (photons) moving through the field, the field itself is constant. Which makes it weird that the Higgs Field could decay and be flexible(?) vs. the Magnetic field; but I guess that's what you meant when pointing out that it is a Scalar field.

This seems to suggest that the field can be different at different places in Space vs. the Magnetic field which is unchangeable, so it possibly could be more energetic or less stable close to a more massive object like the Sun ... matter having a direct effect on the Higgs Field itself.

Makes me wonder what the difference is between the creation of a Higgs boson and something were the Higgs field starts to decay? Is the former more a compression like a black hole while the latter relates more to something the cooling and freezing of matter where it stops being vivid?

6. Jun 6, 2015

### ChrisVer

The difference between the scalar field (like the Higgs field) and a vector field (like the electromagnetic field) is that the first can have a vacuum expectation value without breaking down the Lorentz invariance (because it's a scalar).
The decay of the field, I guess you mean a transition from a false to a true vacuum? In that case you need to have more vacuum expectations values than the trivial ones, again only possible for a scalar field.

The field can be different at different places? Again the electromagnetic field can be different in different positions, the field is described by $A^\mu(x)$ (depends on $x$). The same goes for the Higgs field $\Phi (x)$. However the vacuum expectation value is fixed (and from space for now we moved in the field's configuration space like the diagram you showed), and it can be $v$, or more than one value (if you put more vacua). However all space that we live in exists in a given vacuum, otherwise you would have the formation of domain walls and strings (where the two vacua collide).

The Higgs field decaying, again if seeing as a transition, is totally different to a Higgs boson creation. The Higgs boson can be some perturbation around the vacuum expectation value (you write the physical field as $\phi_{phys}(x) = v + h(x)$, where you interpret $h(x)$ as the Higgs boson), so you are moving perturbatively on your x axis in the diagram around the vev. The other thing (passing from a false to a true vacuum) is a phase transition thing - moving from a higher energetic vev to a lower one.

Last edited: Jun 6, 2015
7. Jun 6, 2015

### ChrisVer

Also I have a feeling that the metastable thing assuming the Standard Model is the only thing there is from our scale up to the Planck scale, does not have more than one vacuum. It has one vacuum and the next is thing there is, is a drop to -infinity of the potential energy... that is more like a valley...

8. Jun 7, 2015

### Michel_vdg

It weren't so much conclusions ... rather thinking/rambling out loud ... as for a Vector field there's always direction while for Scalar field its about magnitude, sort of like water flowing at a point vs. water having a temperature at a point ... I was (wrongly) interpreting the Higgs field as the water substance itself, and the Magnetic field sort of as the channel / field for the water to run in.

Alright. The thought/mistake I made was putting the image from the the false vacuum in the 1st post together with that of the symmetry breaking of the Higgs field ...

... and coming up with this:

... but in you eyes it is more like a bottomless pit ... and that the Vacuum and Higgs bosons that we have now are probably more like footprints on a snow-slope that can fade once there's an large avalananche which would be the ∞