I once met a former physicists turned ERP consultant at IBM, who also told me that there was a small energy band between LEP and LHC, that was actually unreachable in LHC (too low for the beam as designed), and there was a tiny chance the Higgs had a mass that would make the LHC miss the finding (but then some boosted linear accelerators should be able to find first)

Pierre

Basically they have to rule out very masses by proving that they can't see them. experiments at LEP and the Tevatron have put the mass limits between 114 and ~200Gev.

All the standard model higgs (where it's just a higgs boson with no other weird physics) decay into two particles. It depends on the mass of the higgs what these decays are - for instance i'm studying 165Gev which is roughly 2 times the W mass, so in this region this is by far the most likely decay.

So far they've not seen this above the background and the more data they have, the more they can rule it out. The LHC will provide more data at the low (~114) region, where the main decays are b/bbar quarks, photons, tau lepton, c/cbar quarks and two gluons. All of these occur anyway in the detector so it's hard to spot - which is why there has been the least work in this region so far, and why ruling out the less likely WW and ZZ decays has been easier. Although it's the decay that occurs the least, the photon decay is the easiest to spot.

If they don't find the Higgs at any of these energies, it means it's not just a standard model one - i.e. it behaves not just by the laws we already know, but by new physics we've never seen. Supersymmetry and Extra Dimensions are two of the more prominent theories why the Higgs may not be in the standard model region.

That's true. But it is even better. Unless the Higgs has pretty much exactly 116 GeV, so called loop corrections will destroy the model once more, if there are not more particles to shield these effect. As this is a kind of fine tuning people are not heavy with it, there are basically two classes of models introducing new particles.

The one is supersymmetry. This gives to each particle we already know a heavier superpartner, which has the property to cancel the contribution of its original particle in these loops (for physicists not connected to the matter, it makes a boson partner for every fermion and vice versa. In Feynman diagramms fermions come in with a negative sign, bosons with a positive, so the superpartners cancel their normal partners). The proposed particle I wrote in the diary to catlyse fusion is the stau, the superpartner of an even much heavier partner of the electron than the muon. In some parameter space it can be realively long living.

The other is some variation of 'techni color' or 'warped extra dimensions'. This is in general the more 'natural' solution of the problem, but even more than in the case of supersymmetry one would have expected to find deviations of the standard model about 20 years ago.

The good things about the LHC is, that we really enter the region in which these models have to exist, if they should help to solve any problem.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers

One needs something to explain masses, basically a scalar field. There are some theories biulding the scalar field up as a composite of vector fields, but its rather weird.

I think darrkespur was referring to non-standard model Higgses. But as explained elsewhere on the comment section, if the Higgs isn't in the low mass region, there have to be more particles to prevent other problems making the theory inconsistent.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers

You underestimate the importance of HTML in creating the web.

Particle physics had progressed so fast since the 1940's that the particle physics community had developed a system of "preprints" in which people circulated drafts of their papers to colleagues at their institutions and others months before they were published in journals. The story goes that Tim Berners Lee got tired of e-mailing documents back and forth to colleagues at CERN and decided to invent HTML and code a bare bones browser to allow him to (we would today way) webcast his research. There is something about the pace of information exchange within CERN and in the particle physics community that supports the idea that HTML might have taken 5 more years to be developed elsewhere (and it would have been some university or other: USENET and the text-based tools to go with it, and GOPHER, developed in that environment).

The large particle physics laboratories do employ thousands of physicists, engineers and programmers specifically for particle physics experiments purposes, and that is a nonnegligeable fraction of the respective academic communities. If the large labs didn't exist these people would be competing for academic jobs elsewhere and it would result in more people going to industry, as well as fewer people getting doctorates.

If LHC funding hadn't gone through, CERN would have stagnated and maybe shrunk. You need far fewer people to run the existing facilities than you do to develop a new facility, and the LHC research programme is much more intense that what can be carried out at the existinc facilities (not that that isn't useful, too, but it's on a smaller scale in terms of people and resources).

Consider CERN and the LHC a Keynesian stimulus package for physics and engineering.

We have met the enemy, and he is us — Pogo

Three related reasons: Sputnik angst, there was a race with the Soviet Union in every field, and areospace technology development for military purposes.

But the fact is, the Apollo program was a one-shot thing. It was wound down and the US lost its ability to fly to the moon. It also discontinued its high-payload rockets in favour of the Space Shuttle, so now the rocket market is occupied by the European Ariane and the Russian Proton.

The Soviet manned space program made more scientific and technical sense than the American one, and the ISS owes more to the Russian Soyuz and Mir than to the American Skylab, which was also discontinued and folded into the Shuttle.

We have met the enemy, and he is us — Pogo

(1) Spend money on chip research for what? What would the chips be used for? The great proliferation of electronics came on the back of very advanced requirements for components for space programs, etc. One could argue that only once they had been developed for such purposes were it possible to consider their use for more mundane matters. The personal computer only became possible with a maturation of integrated circuit technology, computation infrastructure, and computational techniques that allowed for cheap mass manufacture. The driver for this technology were expensive research programmes in fields requiring processing of large data sets, such as say high energy physics research. Forget about the direct spinoffs, I would argue that the influences of these expensive programmes are far more subtile.  Technological diffusion requires that the basic building blocks are already lying about looking for a different application. You don't start developing processor technology because you think that in 20 years you'll be able to make a machine to play games on.

(2) Missile programmes you say? Because military programmes with large destructive potential are soooo useful while high energy physics, space exploration and the like are vanity projects! And you know how the military loves to share the technology it develops and would not like to keep it secret. One of the great advantages of the large lab high energy physics environment is exactly that it is not a military programme. We don't build things to kill people, I think this is a plus. Further, there is not a tendency to keep progress secret. Quite the opposite in fact, thus a greater chance that progress made here can defuse faster and wider.

(Disclosure, I work at CERN.)

It would be interesting to compare commercial to military / government revenues over time. I should study the topic further because it occurs at the intesection of several topics I'm interested in.

The early commercial viability of mainframes is a good point that I managed to forget. I'll still make my vague 20 year claim, though.

I agree that it all happened shockingly fast.

Most of what's happened has been faster and cheaper, but not so truly innovative.

I disagree. Reading IEEE mags since I became an EE major in college, there has been some stunning work over the years in the semiconductor physics realm that has been required to get the commercially viable transistor sizes we have today. From the computing point of view, though, I agree what you're saying.

you are the media you consume.

An interesting episode in the killing of the SSC was how, during the Congressional hearings, a prominent physicists (someone big, like John A. Wheeler or Murray Gell-Mann or Steven Weinberg) was asked by a congressman whether the LHC would provide evidence of the existence of God. The negative answer did not help.

We have met the enemy, and he is us — Pogo