the Higgs boson is a scalar particle. It is defined, classically, by a single function

Gauge bosons are particles that exhibit a gauge symmetry–namely, they are written down using a certain number of functions, but the actual physics they describe involves a smaller number of functions. Therefore, in describing the actual physics involved with the gauge boson, we are free to set an arbitrary relationship between the various functions that we have written down, before we even begin to solve the problem. The most common example of this is the four dimensional vector potential function in Electricity and magnetism–we are free to add the gradient of an arbitrary function to the vector potential, and we will not change the electric or magnetic fields described by this potential.

In this sense, the graviton is certainly a gauge boson–in order to write down the gravitational field, we need ten functions. Careful analysis, however, reveals that there are only two physically meaningful local degrees of freedom to the gravitational field. Of course, we can’t write down a consistent quantum mechanical description of the graviton, so perhaps this description is wrong.

This leaves us with the vector particles, which are bosons of spin one, that are classically described by four dimensional vectors. We have a perfectly good quantum mechanical theory of vector particles. So, typically, when particle physicists talk of ‘gauge bosons’, the things that they are describing are vector particles.

Things like where the underlying group is SU(2)xSU(2) instead of SU(2)xU(1), and the missing two gauge bosons have a mass in excess of 150 GeV, or where there is no Higgs boson, but instead a cooper pair of two fermions looks like a Higgs, or something like that, ya?

However, new vector bosons possessing higgs-like functionality
(ie, interconversion of left and right fermions) could still exist
(even if no condensate is present); these bosons are also
well suitable for hunting:-).

I fully agree that a Higgs discovery would be useful and wonderful. In the same manner that the discovery of the electron, proton and neutron were. On each occasion much was made of the idea that a complete understanding of the nature of, well, nature, was at hand. Alas, closer inspection, based upon the new knowledge that emerged, only served to show a more subtle and counter-intuitive view.

Having barely enough knowledge to be marginally dangerous, I find a kind of Zen in the idea that all particles are infinitely divisible. OK, there may certainly be a practical, fundamental limit and that is not for me to say. But the idea that there is one ultimate particle strikes me with the same inner discomfort as the idea that there is one ultimate creator or one particular definition of the question to which the answer is 41.99999 . . . . I would sure hate to have to tell everyone that the show is over and pack up the tent in the rain to set off to the next gig not only without a map but without even the possibility of a map existing.

Funny how our individual perceptions and biases color our definitions yet, without actual observation, how can we otherwise define anything practical or fundamental? Ah! The joy of science, mankind’s only legitimate child.

Others have said that it is all not only stranger than we imagine it is; it is stranger than we can possibly imagine (given present knowledge and the tools at hand).

I am anticipating the advent of the LHC. Certainly both our knowledge and our tools will be changed. And then we will be able to draw the map to the next gig.

Nima Arkani-Hamed was at UC Davis a couple weeks ago and gave a talk where he said that if this were the outcome, that would be the “ordinary” outcome, the
easy solution to the problem. Not that we wouldn’t be excited to explore the new forces/particles we find! But finding a Higgs scalar, indicating this Higgs field permeating all spacetime, would be the “extraordinary” outcome, a truly new thing for this field o physics.

There are days when I think that these “compositeness” models might be right after all. And they are not at all out of fashion thee days…

Ultimately it’s an experimental question, and we ma know the answer soon.