CERN’s historic discovery of the elusive Higgs boson — the subatomic particle thought to be at the root of what gives normal matter its mass — may actually represent only a portion of a more complicated and heretofore unexplored particle physics paradigm, say researchers.
After new analysis of CERN (the European Organization for Nuclear Research) observations of the Higgs particle, the authors of a paper recently published in the journal Physical Review D crack the door on the possibility that the Higgs particle actually detected by CERN’s Large Hadron Collider (LHC) may not be fundamental (or point-like). Instead, they argue it could be a composite particle made up of two even smaller techni-quarks, bound by a theoretical “Technicolor” force. Yet much of the particle physics community still needs convincing.
For more than three decades, this hypothetical new force of nature has been termed “Technicolor” and would require the Higgs particle be composed of two techni-quarks.
In contrast to protons and neutrons that are made up of quark particles, bound by nature’s fundamental strong nuclear force, particle physicists say that the force that would hold such techni-quarks together cannot be one of the existing known forces of nature. That’s because neither gravity, the electromagnetic force, the weak nuclear force nor the strong nuclear force are strong enough to do so.
“[The paper] points out that the particle we discovered at CERN might not turn out to be the simple particle predicted in the Standard Model, but a similar particle predicted by a different theory called Technicolor,” UCLA particle physicist Jay Hauser, now on assignment as a CERN project manager, told Forbes.
An example of simulated data modeled for the CMS particle detector on the Large Hadron Collider (LHC) at CERN. Here, following a collision of two protons, a Higgs boson is produced which decays into two jets of hadrons and two electrons. The lines represent the possible paths of particles produced by the proton-proton collision in the detector while the energy these particles deposit is shown in blue. (Credit: Wikipedia)
The key to the Higgs particle is the Higgs field itself which has been compared to “cosmic molasses.” Particles which have mass interact with this unseen field of Higgs particles. And the more mass a given particle has, the more it interacts.
But the Higgs boson has only been measured to a certain precision at the energy levels CERN is currently using. Theorists are quick to point out that there may be more than one Higgs boson or even that the Higgs boson as CERN has currently probed it — at energies of 125 Giga electron Volts (125 GeV), is not sufficiently high to definitively say whether this new particle is composite.
Even so, Mads Toudal Frandsen, one of the study’s co-authors and a particle physicist at the University of Southern Denmark in Odense, told Forbes it will come as a surprise to some how close the properties of a Techni-Higgs can be to those of CERN’s Higgs particle. He notes that although <span display=”Technicolor remains a “time-honored idea for the origin of mass, it has been abandoned by most of the community.”
“The paper studies CERN findings in the light of a Technicolor Higgs,” said Frandsen. “This paper demonstrates that a Techni-Higgs can look very much like a Standard Model Higgs and thus potentially be what LHC has found.”
Critics of the study outlined in the paper, however, point out that their techni-Higgs arguments are neither provable nor disprovable.
But Frandsen counters their Technicolor specifics and arguments can be proven or disproven by future experiments with the Large Hadron Collider and so-called lattice supercomputer simulations of the Higgs particle’s underlying technical dynamics.
“We are certainly not saying that current LHC data does prove Technicolor as the origin of mass for the elementary particles,” said Frandsen. “But we find that some Technicolor models could plausibly still explain our data. Our arguments can be improved and they can ultimately tested by supercomputer simulations and by LHC experiments.”
To that end, Frandsen notes that he and colleagues are actually currently working with CERN collaborators on strategies to verify or falsify the Technicolor scenario as the origin of mass. He points out that if Technicolor were true, with a sufficiently high energy collider, physicists would be able to see the Techni-quark constituents of the Techni-Higgs — the same way they can see the quark particle constituents of protons.
Hauser says the prospect of confirming a Techni-Higgs makes the idea of taking more data at CERN all the more exciting. He notes that in 2015, the accelerator will produce collisions of protons at higher energy (13 versus 8 trillion electron-volts).
At present, there is still no evidence that the Standard Model needs extending to include a Technicolor scenario, says Darin Acosta, a particle physicist at theUniversity of Florida in Gainesville. That is, Acosta told Forbes, even if the conventional model does leave many unanswered questions, such as the makeup of some 85 percent of mass in the universe, by so-called “non-baryonic” (or exotic) Dark Matter.
Still, Frandsen says at least one such configuration of techni-quarks could explain Dark Matter.
Is there room for Higgs physics beyond the Standard Model?
Although there is room for deviations from the Standard Model, no statistically significant ones have thus far been established, Robert Shrock, a theoretical particle physicist at Stony Brook University in New York, told Forbes. The bottom line, he says it that CERN’s Higgs-like particle is consistent with the Standard Model Higgs boson.
As Shrock points out, the LHC experiments test this consistency by measuring the production and decay of the Higgs in a number of different channels to within theoretical and experimental uncertainties. Thus far, all point to the CERN’s discovery being what he terms a “point-like Standard Model Higgs boson.”
When can we expect definitive answers?
“The next 2015 CERN run will be three years long and produce about 10 times as many of the higher-energy collisions as all the data we took during 2010-2012,” said Hauser. “We might discover one or more of the additional particles predicted by Technicolor or maybe something ‘funny’ about the Higgs [itself].”
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