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Higgs boson is running out of places to hide

The elusive Higgs boson, thought to give all other particles mass, is running out of places to hide. A new deluge of data from the Large Hadron Collider's twin particle detectors has ruled out a wide range of possible masses for the theoretical particle.

The Higgs is the last undiscovered particle in the standard model of physics, the leading theory for how particles and forces interact.

Data from the LHC's ATLAS and CMS detectors have now ruled out – with a confidence level of 95 per cent – all masses for the Higgs between 145 and 466 gigaelectronvolts (GeV). That covers the bulk of the mass range that is easiest for physicists to explore.

"We're ruling out the easy bits, and we're leaving the harder bits still to study," says James Gillies, spokesman for CERN, the particle physics lab in Switzerland where the LHC is based. "There's still a lot of space left, but it's the space that's harder for us to analyse."

Hiding out

The announcement, made on Monday at the biennial Lepton-Photon conference in Mumbai, India, came on the heels of a hopeful whiff of the Higgs announced at the Europhysics Conference in Grenoble, France, in July. The LHC has collected twice as much data in the month since the Grenoble conference.

That intriguing signal was found around 140 GeV, which is still in the allowed range, albeit barely. But physicists at the time warned that the signal could just be due to statistical fluctuations. With the extra data, the significance of the signal has indeed gone down, CERN says.

The Higgs is most likely hiding out between 115 and 145 GeV – at the low end of what the LHC can detect, Gillies said. The LHC's predecessor, the Large Electron Positron Collider (LEP), ruled out masses below 115 GeV before it shut off in 2000.

'End game'

"We are definitely approaching the end game in looking for the Higgs," Gillies says. "But we don't want to give the impression that the answer is just around the corner." Teams at the LHC hope to double the amount of data they currently have by the end of this year, but they will need to double that again to say for sure if the Higgs is there or not. Collecting that much data will probably take the better part of a year if nothing goes wrong, Gillies says.

Physicists are not panicking about the fate of the Higgs yet, but they may be getting frustrated. If the Higgs is indeed hiding in the low mass range, "a malicious deity has carefully chosen the Higgs mass to make it as hard as possible for physicists to study it", said Peter Woit of Columbia University on his blog, Not Even Wrong.

They're also starting to worry about what it means for physics if the Higgs isn't there, Gillies said. If it doesn't exist, physicists will have to come up with another explanation for why matter has mass.

And even if the LHC comes up Higgs-less at the end of next year, there could be other, stranger versions of the Higgs that do not fit into the standard model – and thus could point to entirely new physics.

"[That] would be really cool," says Gillies, adding that these bizarro versions could potentially lie in the mass range that has just been excluded for the "garden-variety" Higgs. "That's what everyone wants – something that goes beyond the standard model."


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Told You So

Tue Aug 23 12:54:51 BST 2011 by Julian Mann

I have been saying that there is no Higgs particle for a long time now in comments on articles that have appeared in the past on the Higgs. In fact I believe that most scientists suspected this because the range of likely masses for it had already been tested by the Tevatron and other detectors, long before the LHC was built. Thus the justification for the LHC itself is highly dubious. Was that the best way to spend such a colossal amount of resources? Also I do not think the Graviton will be found either. The Standard model is in error to assume the existence of either so called particle. Instead I think we should be looking at extending the Big Bang model to incorporate the survival, not annihilation of antimatter. Mass and Gravity may well be the result of the interaction between matter and dark matter(which I hold to be antimatter suspended in an alternate quantum phase)

Apart from any of this I find it highly paradoxical, that the Higgs which is supposed to give particles mass, also has mass.Where did it's mass come from? (and I don't accept the answer "from another type of Higgs")

Told You So

Tue Aug 23 14:05:44 BST 2011 by Mark Bridger

A lot of people have been saying that there should not be a particle that nominally gives others mass. Mass is the energy that a particle possesses, so the idea of the Higgs particle is absurd. Theorists may see a pattern in the standard model and then extend the pattern to speculate on the existence of other particles but that is not proper logic. You need to first understand why there is a model before theorising why or how any apparent pattern should be extended

Told You So

Tue Aug 23 15:45:06 BST 2011 by ajax

I think we must start thinking quantum this time!! I mean it I say quantum field theory!! It can explain space time mass energy dimensions etc etc etc

Told You So

Thu Aug 25 01:15:39 BST 2011 by Gary B

Your idea is based on the idea of a 'particle' as a solid thing, which after struggling with the same problem, I have come to recognize is not really very useful. Remember that light can be seen as both a wave and a 'particle' depending on how one looks at it. So a 'photon' is better seen as something that can appear as either one.

The same is true of all 'particles'. It's better to look at a particle as a locus of energy, or even better merely as an attractor in the field equations that happens to exhibit certain behaviors (I'm handwaving a bit here, on the terminology). that's really what all 'particles' - electrons, protons, whatever - are. They are just loci where the various fields of energy-stuff 'collect together' (for lack of a better term), that happen to be affected by, and affect, other energy-stuff around them.

One might even say that particles are the 'rogue waves' of the multi-dimensional quantum ocean. :D

Which raises a very odd question - would the anti-particles have started out analogously like the troughs that usually lead the rogue-wave peaks (in a water ocean? In a multi-dimensional 'ocean' it would be easy for the two components to get separated. :D

Told You So

Thu Aug 25 11:36:47 BST 2011 by Julian Mann

Gary, you refer to wave/particle duality. However in my view this still requires explantion. I would say that the wave part is due to propagation in "anti-time" We as classical observers can only observe events in classical time, events at the Quantum level take place in "anti-time" which we perceive as a "Wave".

I don't go for any of this multi-dimensional nonsense. We do not need anything beyond the usual 3 space dimensions and 1 time dimension(albeit bi-directional) Both time directions share the same space co-ordinates a la Minkowski.

Told You So

Tue Aug 23 21:42:37 BST 2011 by Adolph

You may have doubts if Higgs particle exists but how can you know for sure if you do not look for it?

The money spend on basic research (which LHC does) that attempts to find what are the fundamental building blocks of matter is nothing in comparison to money spend by governments on military. Do you ever think of better use for those founds?

Big Bang is a consequence of Standard Model and cannot replace it.

The survival of antimatter? What antimatter? There aren't any left, at least we can't see any.

Could you kindly explain what is it that you mean by "alternate quantum phase"?

Higgs can acquire mass by interaction with higgs field.

Told You So

Tue Aug 23 21:50:36 BST 2011 by Adolph

That's where you can find more about higgs boson

Told You So

Wed Aug 24 12:51:11 BST 2011 by Julian Mann

Adolph, The Higgs was virtually ruled out by other detectors before the LHC became operational, and there were heavy hints of this while the project was being planned. The problem of expending resources in this way is that the money could have been used to better purpose on another project. Also future funding of such projects may be problematical, given government cut-backs. The money spent on the LHC would have been enough for example to clear most of Ireland's national debt.

I cite Big Bang as being an area of research worth spending time and money on, because the explanation for Mass and Gravity may well be found there. Big Bang is a very useful model, but incomplete.

The Big Bang model at present has matter and antimatter annihilating, leaving a small remnant of matter surviving, which I find far fetched. If however antimatter survived Big Bang in equal quantities to matter, that would then explain a lot of outstanding issues facing physics today, especially if Dark Matter turns out to be antimatter(partitioned ex Big Bang) See my letter published about a year ago in New Scientist. The Alternate Quantum Phase was just a means of keeping matter and antimatter apart at big Bang. In simple terms please refer to Universe in a Nutshell by Stephen Hawkings, P48 where he deals with particles with Spin 1/2. These require 2 complete revolutions to return to their base state. I see either matter or antimatter as having been suspended at the half way house, i.e. after only one revolution. In that state it cannot interact normally with it's antimatter/matter counterpart and hence the antimatter part of this set-up would be invisible to us, but we are able to feel it's Gravitational force.(This must be Dark Matter, there is no other satisfactory explanation for it.)

The other piece of the jig-saw missing in the Big Bang theory is the alternative directional of time. I hold time must be bi-directional, and it is puzzling to a lot of scientists, that classical time appears only to travel in one direction. If however time is truly bi-directional, then we can derive explanations for other outstanding issues such as reconciling Relativity to QM

Told You So

Wed Aug 24 21:11:39 BST 2011 by Adolph

Julian. Particle colliders attempt to recreate conditions that were "out there" shortly after the big bang. The LHC being most powerful up to date brings us closer to the moment of big bang and allows scientists to study those condition in more details than ever before. This is where your theory of "alternate quantum state" could be tested or explored. Therefore I am not sure why do you think money spent on LHC misplaced.

There is a good reason why most scientist think that antimatter annihilated. It is because this is what is observed when they interact with one another. Therefore perhaps you should suggest the physical mechanism which would put it in the "alternated quantum state" thus creating dark matter. This then could be tested (perhaps using LHC) to confirm or disprove this theory.

"Spin" of the quantum particles does not refer to it going around it's axis. Spin is it's quantum mechanical property. This one is a bit tricky to envision but this is something fixed like charge or mass of the given particle.

Time is most persisting illusion as proven by Einstein. The idea of time being one directional is puzzling, no denying that, and our best explanation if it comes from second law of thermodynamics which in essence tells us of improbability of certain types of initial conditions (that is there is many more ways to break a cup and only relatively few to have it intact).

As to reconciling Relativity with QM... well the jury is still out there, so good luck.




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