Is the Higgs boson a piece of the matter-antimatter puzzle?

December 16, 2014
In this illustration, two protons collide at high energy, producing a Higgs boson that instantly decays, producing two tau particles. The rest of the energy from the collision sprays outward in two jets (pink cones). Measuring the angle between these jets could reveal whether or not the Higgs is involved in charge-parity (CP) violation, which says that nature treats a particle and its oppositely charged antiparticle differently. A SLAC researcher and his colleagues propose such an experiment in a recent paper in Physical Review D. Credit: SLAC National Accelerator Laboratory

( —Several experiments, including the BaBar experiment at the Department of Energy's SLAC National Accelerator Laboratory, have helped explain some – but not all – of the imbalance between matter and antimatter in the universe. Now a SLAC theorist and his colleagues have laid out a possible method for determining if the Higgs boson is involved.

In a paper published in Physical Review D, they suggest that scientists at CERN's Large Hadron Collider (LHC), where the Higgs was discovered, look for a specific kind of Higgs decay when the collider starts up again in 2015. The details of that decay could tell them whether or not the Higgs has a say in the -antimatter imbalance.

"The time to plan a search strategy is now," said Matt Dolan, a research associate in SLAC's Particle Theory group and co-author of the paper. "That way, when the LHC begins to operate at full strength we'll be ready."

Why there's more matter than antimatter is one of the biggest questions confounding particle physicists and cosmologists, and it cuts to the heart of our own existence. In the time following the Big Bang, when the budding universe cooled enough for matter to form, most matter-antimatter particle pairs that popped into existence annihilated each other. Yet something tipped the balance in favor of matter, or we – and stars, planets, galaxies, life – would not be here.

The recently discovered Higgs boson is directly connected to the issues of mass and matter. Asking whether the Higgs is involved in the preponderance of matter over antimatter seems a reasonable question.

The paper is based on a phenomenon called CP – or charge-parity – violation, the same phenomenon investigated by BaBar. CP violation means that nature treats a particle and its oppositely charged mirror-image version differently.

"Searching for CP violation at the LHC is tricky," Dolan said. "We've just started to look into the properties of the Higgs, and the experiments must be very carefully designed if we are to improve our understanding of how the Higgs behaves under different conditions."

First, researchers need to confirm that the Higgs fits into the Standard Model, our current best explanation of matter, energy and the processes that turned them into us. A Higgs that fits the Standard Model where CP violation is concerned is called CP-even; one that does not is called CP-odd. A tell-tale sign that the Higgs is involved in CP violation is if it's a mixture of even and odd.

The theorists proposed that experimenters look for a process in which a Higgs decays into two tau particles, which are like supersized cousins of electrons, while the remainder of the energy from the original proton-proton collision sprays outward in two jets. Any mix of CP-even and CP-odd in the Higgs is revealed by the angle between the two jets.

"This is a very high-profile and involved analysis," said Philip Harris, a staff physicist at CERN and co-author of the paper along with Martin Jankowiak of the University of Heidelberg and Michael Spannowsky of Durham University. A member of the CMS collaboration, Harris focuses on Higgs-to-tau-tau decays, evidence of which has only recently begun to mount.

"I wanted to add a CP violation measurement to our analysis, and what Matt, Martin and Michael proposed is the most viable avenue," Harris said, adding that he's looking forward to all the data the LHC will generate when it starts up again early next year at its full design strength.

"Even with just a few months of data we can start to make real statements about the Higgs and CP violation," he said.

Explore further: Maybe it wasn't the Higgs particle after all

More information: Matthew Dolan et al., Physical Review D, 21 October 2014 . DOI: 10.1103/PhysRevD.90.073008

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Dec 16, 2014
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2.1 / 5 (7) Dec 16, 2014
Whatever caused CP violation (and something obviously did, so we don't live in a universe that is charge parity neutral) is probably VERY subtle. I think it's gonna be hard to find. It would be great if the higgs gave us the answer.
2.3 / 5 (3) Dec 16, 2014
imido: that graph doesn't display that the higgs is composed of "two" ones. The Higgs can decay in a number of ways. One way it can decay is to two photons (gamma gamma, the red trace), and another is to two Z bosons (the blue trace) which in turn decay into 4 leptons (electron and neutrino - like particles).

Because detectors work in different ways, the ways in which they detect the Higgs may be off-set from each other to some degree.

So if you just took *one* measurement, you'd think the Higgs falls within the dashed line with 95% confidence and the solid line to 68% confidence. But when you combine the two *separate* measurements, and see where they overlap, you can see the new combined measurement (in black).
Dec 16, 2014
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1 / 5 (2) Dec 17, 2014
It only make sense that there are imbalances in local space. Otherwise things does not stabilize as matter. Only real question for me is weather anti-matter dominant side is on other part of this universe or in other dimensions.
Dec 17, 2014
This comment has been removed by a moderator.
2 / 5 (4) Dec 17, 2014
RightO I'll add my two cents in. It was just the other day an article mentioned that a newly examined Newtonian Gravity showed that there could be two Universes, both reaching out from the BigBang heading in opposite directions in Time. Either Universe would appear normal, but times is going backward compared with each other. Now what if... what if this other Universe happens to be Anti-Matter???? YEah I know, throw the single votes at me, as this isn't really science, just conjecture, but it shouldn't be ignored either!!!! I seem to remember Richard Feynman saying that anti-matter is just matter travelling backwards in time and he somehow indicated this on his feynman diagrams.
1.7 / 5 (6) Dec 17, 2014
The "fundamental" model yields a an endless number of particles.
A Nobel prized said one should be careful not to include more than one "new" particle per article.
99.99998% of all events in the LHC are discarded BEFORE being analysed because they don't "fit" in the "model"...
If you just know fundamental statistics you know this is absolutely, crap.
Read the book The Higgs Fake to have just a glimpse on the state of the "art" of the standard model and all downstream research.
1 / 5 (2) Dec 17, 2014
The Explorer just leaving the solar system appears to have struck a "bow wave" of energy that is being pushed around our system. If this is the case that suggests a very large amount of energy free in the universe which can add theories on both dark matter and suggest that the "imbalance" between matter and anti-matter is a great deal smaller than suggested.

Is the problem in the motions of the universe not with dark matter but with free energy that the matter has to claw it's way through?
1 / 5 (3) Dec 17, 2014
Supersymmetry exists INSIDE the photon structure. With all larger particles composed of these building blocks, there actually is no imbalance. BTW, the background red shift is due to a gradual loss of photonic energy as they propagate and interact with various fields in their journey through space: no expansion is required.
1 / 5 (3) Dec 17, 2014
Also, the universal "single force", that Einstein said was the only force that originally exists, is the charge attraction of opposite charges. A 'finding' from the LANL plasma research facility was that the interaction of opposite charges acts at right-angles, thereby inducing a rotation. For particles of equal mass but opposite charge, the attraction can be equally balanced by the rotational centrifugal force, resulting in a stable photon. For particles of mass lower than threshold gammarays (1.0216 Mev), the photon remains stable, but with a smaller rotational radius external fields can affect the bond, resulting in pair formation. Without external fields, stability could be maintained to form larger energy particles -- up to, at least, meson mass.
5 / 5 (1) Dec 17, 2014
", two protons collide at high energy, producing a Higgs boson that instantly decays, producing two tau particles. The rest of the energy from the collision sprays outward in two jets (pink cones). Measuring the angle between these jets could reveal whether or not the Higgs is involved in charge-parity (CP) violation..."

How can you collide two protons without knowing the mass.radius relationship of the proton?

The proton radius problem is not able to be explained by the standard model (see polynomial fits article), thus, how can the standard model physics be used to extract any information from the collision of the protons when the proton data (CODATA) is not understood?

I'm just asking questions.... ;-)
3.7 / 5 (6) Dec 18, 2014
The "fundamental" model yields a an endless number of particles
Oh yeah? Name 'em. Use aleph numbers if you need.
If you just know fundamental statistics you know this is absolutely, crap
If you just know fundamental statistics you have a great deal more to learn about high-energy physics, and science in general.
Read the book The Higgs Fake to have just a glimpse on the state of the "art" of the standard model and all downstream research.
If only a glimpse is required, provide one, and let's just see about fakery, shall we?

Oh, and see Amazon's "Most Helpful Customer Reviews" on it –
5 / 5 (1) Dec 21, 2014
higgs boson is only a flux of quantum vacuum, it is not a real stable
not rated yet Dec 28, 2014
The solution to the proton mass.radius problem implies there is no Higgs:
MpRp=4LM <-- THIS IS THE SOURCE OF MASS OF MATTER, the vacuum fluctuation dynamic, the fabric of spacetime.

Mp=Mass of proton
Rp=Radius of proton
L=Planck Length
M=Planck Mass


Mp=1.67262177774e-27 kg
Rp=Radius of proton
L=1.61619926e-33 cm
M=2.1765113e-8 kg

Google Calculator for Rp=

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