Exploring the Higgs boson's dark side

July 21, 2015 by Pete Wilton

In 2012 CERN's Large Hadron Collider (LHC) discovered the Higgs boson, the 'missing piece' in the jigsaw of particles predicted by the Standard Model.

Last month, after two years of preparation, the LHC began smashing its beams together at 13 Trillion electron Volts (TeV), close to double the energy achieved during its first run.

'We do not know what we will find next and that makes the new run even more exciting,' Daniela Bortoletto of Oxford University's Department of Physics, a member of the team running the LHC's ATLAS experiment, tells me. 'We hope to finally find some cracks in the Standard Model as there are many questions about our universe that it does not answer.'

One of the big questions concerns , the invisible 'stuff' that astrophysicists estimate makes up over 80% of the mass of the Universe. As yet nobody has identified particles of dark matter although physicists think it could be the lightest supersymmetric (SUSY) particle.

'In the new run, because of the highest-ever energies available at the LHC, we might finally create dark matter in the laboratory,' says Daniela. 'If dark matter is the lightest SUSY particle than we might discover many other SUSY particles, since SUSY predicts that every Standard Model particle has a SUSY counterpart.'

Then there's the puzzle of antimatter: in the early Universe matter and antimatter were created in equal quantities but now matter dominates the Universe.

'We still do not know what caused the emergence of this asymmetry,' Daniela explains. 'We have finally discovered the Higgs boson: this special particle, a particle that does not carry any spin, might decay to dark matter particles and may even explain why the Universe is matter dominated.'

Discovering the Higgs boson was a huge achievement but now the race is on to understand it: a prospect that Daniela is particularly excited about.

'This particle is truly fascinating,' she says. 'Spin explains the behaviour of elementary particles: matter particles like the electron have spin 1/2 while force particles like the photon, which is responsible for the electromagnetic interaction, have spin 1. Spin 1/2 particles obey the Pauli principle that forbids electrons to be in the same quantum state.

'The Higgs is the first spin 0 particle, or as particle physicists would say the first 'scalar particle' we've found, so the Higgs is neither matter nor force.'

Because of its nature the Higgs could have an impact on cosmic inflation and the energy of a vacuum as well as explaining the mass of elementary particles.

Daniela tells me: 'Because of the Higgs the electron has mass, atoms can be formed, and we exist. But why do elementary particles have such difference masses? The data of run 2 will enable us to study, with higher precision, the decays of the Higgs boson and directly measure the coupling of the Higgs to quarks. It will also enable us to search for other particles similar to the Higgs and determine if the Higgs decays to dark matter.'

Daniela is one of 13 academics at Oxford working on ATLAS supported by a team of postdoctoral fellows, postgraduate students and engineering, technical, and computing teams. The Oxford group plays a lead role in operating the SemiConductor Tracker (SCT), most of which was assembled in an Oxford lab. This provides information on the trajectories of the particles produced when the LHC's beams collide, which was crucial to the discovery of the Higgs boson.

Whilst the next few years will see the Oxford group busy with research that exploits the LHC's new high-energy run, the team are also looking ahead to 2025 when the intensity or 'luminosity' of the beams will be increased.

The LHC is filled with 1,380 bunches of protons each containing almost a billion protons and colliding 40 million times per second. This means that every time two bunches of protons cross they generate not one collision but many, an effect called 'pile-up'.

'After this luminosity upgrade the LHC will operate at collision rates five to ten times higher than it does at present,' Daniela explains. 'In run 1 of the LHC we had a maximum of 37 pile-up collisions per crossing but with the upgrade to the High Luminosity LHC, or 'HL-LHC', this will increase to an average of 140 pile-up events in each bunch crossing.'

With the HL-LHC generating many more collisions, the international Oxford-led team are designing and prototyping parts of a new semiconductor tracker that will be needed to help reconstruct particles from the complex web of decay trails they leave inside the machine.

As the LHC ramps up both its energy and luminosity it promises to give scientists working on experiments such as ATLAS answers to some of the biggest questions in physics. One thing is certain: this new physics will also lead to a whole set of new questions about the matter that makes up us and the Universe around us.

Explore further: What will we find next inside the Large Hadron Collider?

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53 comments

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bschott
1.7 / 5 (11) Jul 21, 2015
When future scholars look back at these experiments, they will be embarrassed that their predecessors thought that they were learning about the nature of reality from them.

we might finally create dark matter in the laboratory,


How do you plan to detect it?

The Higgs is the first spin 0 particle, or as particle physicists would say the first 'scalar particle' we've found, so the Higgs is neither matter nor force.'


This would explain the length of it's tenure in OUR reality

that will be needed to help reconstruct particles from the complex web of decay trails they leave inside the machine.


The decay rate is a clue about their significance to our reality

the LHC began smashing its proton beams together at 13 Trillion electron Volts (TeV)


One place observed in the natural universe where this takes place...not mathematically hypothesized...one actual place please.
arom
Jul 21, 2015
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docile
Jul 21, 2015
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docile
Jul 21, 2015
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TechnoCreed
5 / 5 (14) Jul 21, 2015
@bschott
One place observed in the natural universe where this takes place...not mathematically hypothesized...one actual place please.
Right here in earth's atmosphere, we can monitor particles that have been accelerated with many times more energy than at the LHC. https://en.wikipe...particle
PhysicsMatter
1.7 / 5 (6) Jul 21, 2015
Danish scientists last year analysed all the LHC data (Phys.Rev Lett.) from previous run and concluded that data is insufficient to make any judgment. I guess Hicks was sick or told them he was sick so they rushed to give to him his bozon Nobel since dead would not get it.
By the way, was in this post any news?
They are running it for over two months now. What's going on?
Another embarrassing mishap? I mean 10 billion euro embarrassing?
bschott
1 / 5 (7) Jul 21, 2015
@bschott
One place observed in the natural universe where this takes place...not mathematically hypothesized...one actual place please.
Right here in earth's atmosphere, we can monitor particles that have been accelerated with many times more energy than at the LHC. https://en.wikipe...particle


Well, we can. But at no point can any of those accelerated particles collide with a stationary one, the field which is responsible for accelerating those particles will not allow one of the same charge to remain stationary.
docile
Jul 21, 2015
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Job001
1 / 5 (3) Jul 21, 2015
The simplest theory is that the missing mass of the universe is alternate forms of hydrogen, most likely molecular rather than atomic, and even possibly fractional atomic forms created within condensed matter. http://www.newton...dex.html
Occam's razor would advise us to accept the simplest theory.
In this case, it is likely the most abundant element hydrogen in alternate forms constitutes the majority of the missing mass of the universe. Supporting evidence is abundant yet ignored by funding biased researchers who seek continued funding for WIMP ghost hunts. Only in recent history has spectroscopy instrumentation advanced sufficiently to illuminate the issue.
docile
Jul 21, 2015
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Hyperfuzzy
1.8 / 5 (5) Jul 21, 2015
OK, if you buy the above, I have a particle; of which, if the owner purchases it from me, it will transform into an anti-gravity particle. In order to duplicate the particle, simply place it in front of a mirror. Asking price 1T$. Will negotiate with the right buyer.
Hyperfuzzy
1.8 / 5 (5) Jul 21, 2015
Also, I know where dark matter is hiding. For the answer, send 50, 000$ to ... Trust me, it's not in the dark! You will want to know this, miracles revealed! Just think, the TV show will make 100s of millions. The movie! Not to mention the answer to all the mysteries in your head!
Hyperfuzzy
1 / 5 (3) Jul 21, 2015
Danish scientists last year analysed all the LHC data (Phys.Rev Lett.) from previous run and concluded that data is insufficient to make any judgment.
Do you mean http://phys.org/n...cle.html at all cost - or they would face the lost of jobs and money.

Problem is, what are the simulated effects? Oh, forgot, they first have to define the mystery, find a mode, and name it Higgs; still, mystery unresolved!
Hyperfuzzy
1 / 5 (3) Jul 21, 2015
The simplest theory is that the missing mass of the universe is alternate forms of hydrogen, most likely molecular rather than atomic, and even possibly fractional atomic forms created within condensed matter. http://www.newton...dex.html
Occam's razor would advise us to accept the simplest theory.
In this case, it is likely the most abundant element hydrogen in alternate forms constitutes the majority of the missing mass of the universe. Supporting evidence is abundant yet ignored by funding biased researchers who seek continued funding for WIMP ghost hunts. Only in recent history has spectroscopy instrumentation advanced sufficiently to illuminate the issue.

eh, i don't think because nature disagrees with your theory, she is hiding something.
liquidspacetime
1 / 5 (2) Jul 21, 2015
The mass which fills 'empty' space is beginning to be referred to as the 'dark mass' in order to distinguish it from the baggage associated with dark matter.

'Dark Energy/Dark Mass: The Slient Truth'
https://tienzengo...t-truth/

"That is, all that we are certain about [is] the dark mass, not dark matter, let alone to say about the dark 'particle'."

What physics mistakes for the density of the dark matter is actually the state of displacement of the dark mass.

Particles of matter move through and displace the dark mass, including 'particles' as large as galaxies and galaxy clusters.

The Milky Way moves through and displaces the dark mass.

The Milky Way's halo is the state of displacement of the dark mass.

The Milky Way moves through and curves spacetime.

The Milky Way's halo is curved spacetime.

The state of displacement of the dark mass *is* curved spacetime.
Steve 200mph Cruiz
5 / 5 (5) Jul 21, 2015
We could detect it through inferences through the law of conservation of energy. We know the mass of the higgs, when it decays, it should decay in a sensible way. If there is energy missing from its decay, and that energy is equal to a hypothesized dark particle, that would give us an excellent direction to look.

That's how neutrinos were first theorized, they noticed missing energy in certain nuclear decays, and eventually the neutrino model was proven to be correct.
Seeker2
1 / 5 (1) Jul 21, 2015
Here's one for Occam: matter particles displace the dark energy or maybe the Higgs field. Therefore the density of dark energy inside large objects is less than that in small objects. The difference in these densities causes a dark energy pressure gradient we perceive as gravity. Antimatter particles compress dark energy, so the density of dark energy inside antimatter objects is greater than the dark energy in a vacuum. Antimatter objects would cause an even greater gradient in dark energy density and a higher unstable state. Antimatter objects would then decay very rapidly and reach their most stable energy state when they are distributed evenly throughout space time. So there's plenty of antimatter particles out there, all trying to stay as far away from each other as possible. Could be why overall the universe is flat - positive curvature of matter is overall balanced by the negative curvature of antiparticles.
OceanDeep
1 / 5 (1) Jul 21, 2015
What I want to know is why does each "copy" of matter and energy (electrons, protons, etc.) each have features exactly identical to each other? Every proton is the same as every other proton, isn't it? Or is it?

For some reason this article made me think of this for the first time in a long, long time. It's kind of amazing - countless exactly identical copies of these things spread out across all of the observable universe. I know it seems self-evident and obvious, but I can't help thinking there is a big clue in that fact - unless it isn't true and some electrons are inexact copies of each other - not sure if antimatter counts.

I have no formal scientific training, just wondering. :-)
TechnoCreed
5 / 5 (4) Jul 21, 2015
@OceanDeep
What I want to know is why does each "copy" of matter and energy (electrons, protons, etc.) each have features exactly identical to each other? Every proton is the same as every other proton, isn't it? Or is it?
Yes. They are all perfectly alike, but as far as fermions are concerned, they are fighting for their own distinctiveness through the Pauli exclusion principle. https://en.wikipe...rinciple , https://www.youtu...b3Pc4PA4
docile
Jul 21, 2015
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bluehigh
2.5 / 5 (4) Jul 22, 2015
If something is made as simple as possible then, logically, it's impossible to make it simpler.

Einstein was just messing with your mind for fun.

docile
Jul 22, 2015
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antialias_physorg
5 / 5 (4) Jul 22, 2015
Every proton is the same as every other proton, isn't it?

Depends on the context. While you can plug in a proton/electron instead of another proton/electron without any changes in chemical/electrical properties each proton does have unique set of features (position, velocity (to within the uncertainty limit), spin direction, ...). So they're not fully identical.

Their makeup is identical (i.e. each proton is made up of the same types of quarks - which means all properties that are associated with just such a conglomerate of quarks - like electrical charge - is the same).
That there are so many identiacl gismos whirring around is an indication that when nucleosynthesis happened there were only a few likely/stable configurations
https://en.wikipe...ynthesis
(Note that the neutron is NOT a stable configuration by itself - which accounts for the drop in proton-neutron ratio early on)
docile
Jul 22, 2015
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docile
Jul 22, 2015
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docile
Jul 22, 2015
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bschott
1 / 5 (3) Jul 22, 2015
We could detect it through inferences through the law of conservation of energy. We know the mass of the higgs, when it decays, it should decay in a sensible way. If there is energy missing from its decay, and that energy is equal to a hypothesized dark particle, that would give us an excellent direction to look.

That's how neutrinos were first theorized, they noticed missing energy in certain nuclear decays, and eventually the neutrino model was proven to be correct.


But DM has no EM energy, no vibration, no frequency. To infer that missing energy from a decay event departed the EM spectrum to become DM violates a few laws (including the one you named to support your position). Your method of detection only works for objects detectable in the EM spectrum.

3 X 5 out of 5 for that, I'm guessing there are people here who think science is "cool" but don't actually understand it....
Steve 200mph Cruiz
5 / 5 (3) Jul 22, 2015
Bschott,
What are you talking about?
Neutrinos do not interact electromagneticly either.

The law of conservation of energy states "energy can not be created or destroyed, it can only change form" also since mass is energy, and energy is mass, the conservation of energy is equivalent to a law of the conservation of mass.

You're also assuming properties of dark matter that have not been conclusively proven. There is some possible evidence that dark matter could decay into photons.

What laws are being violated and specifically how is it a violation?
bschott
2 / 5 (4) Jul 22, 2015
You're also assuming properties of dark matter that have not been conclusively proven.


What exactly are mainstream theorists doing? What do you think you just did by assuming it could be detected as a decay product? EVERYTHING about DM is assumed so debating it's properties is a futile endeavor for both sides isn't it?

Again, for you and your 3 amigos, if it has photons as a decay product this means that it has an EM energy component that is detectable...so when you find it, let's discuss it's properties.

Neutrino:

" Various detection methods have been used. Super Kamiokande is a large volume of water surrounded by phototubes that watch for the Cherenkov radiation emitted when an incoming neutrino creates an electron or muon in the water." - Wiki

Neutrinos do not interact electromagneticly either.


What are YOU talking about?

bschott
1 / 5 (3) Jul 22, 2015
The law of conservation of energy states "energy can not be created or destroyed, it can only change form" also since mass is energy, and energy is mass, the conservation of energy is equivalent to a law of the conservation of mass.


Yep, these would be the laws. Gravity does not equal mass, gravity does not equal energy. You really need a particle of DM to further a discussion on it's properties.
docile
Jul 23, 2015
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TechnoCreed
5 / 5 (5) Jul 23, 2015
@bschott
" Various detection methods have been used. Super Kamiokande is a large volume of water surrounded by phototubes that watch for the Cherenkov radiation emitted when an incoming neutrino creates an electron or muon in the water." - Wiki
Neutrinos do not interact electromagneticly either.
What are YOU talking about?
Neutrinos themselves are totally invisible to detectors. We only detect after-effects of their interactions with nucleons. For us on earth of flux of "about 65 billion solar neutrinos per second pass through every square centimeter"._wiki: neutrino_Only the few that happen to have an interaction with a nucleon leave traces of their existence. Those interactions are mediated by the weak nuclear force only.
Seeker2
1 / 5 (1) Jul 23, 2015
So if we know, how the dark matter fluctuations look like, we can also predict the geometry of Higgs field - and vice-versa.

Assuming dark matter displaces the Higgs field, the density of the displaced Higgs field would follow the geometry of dark matter displacing the Higgs field. If the Higgs field is what gives the vacuum its matter, its variable density also gives the gravitational field. Then what I was talking about earlier with the dark energy should actually be the energy of the Higgs field.
In spontaneous Lorentz symmetry breaking, energy pushes the vacuum higher up in the potential well added to the Lagrangian, resulting in higher energy particle creation. So the power of the Higgs mechanism would be driven by the dark energy, and you could just as well refer to the dark energy as the Higgs field.
bschott
1.8 / 5 (5) Jul 23, 2015
@TechnoCreed

Creation of an electron or a Muon is an electromagnetic reaction. The weak force has been changed to the "electroweak" force by the powers that be due to the hypothesized nature of it.

We can only detect something if it produces a reaction in the EM spectrum.

docile
Jul 23, 2015
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bschott
1.8 / 5 (5) Jul 23, 2015
LMAO...I have a new fan. Thank you Tooty, for creating a PO account today just to go back and downvote every one of my posts. You are clearly a well grounded individual, but you may have too much time on your hands. Perhaps a science news forum isn't what you really need to pass your time enjoyably. This place is hilarious.
Seeker2
5 / 5 (1) Jul 24, 2015


Assuming dark matter displaces the Higgs field,
Wrong assumption. Dark matter is a displacement of the Higgs field at the macroscopic level. Massive Higgs particles are displacements of the Higgs field at the microscopic level. Good luck finding dark matter particles at the microscopic level.
viko_mx
1 / 5 (2) Jul 24, 2015
Let us first find the bright side of the Higgs boson. In the dark one more easily can lose the way.
viko_mx
1 / 5 (2) Jul 25, 2015
"Neutrinos themselves are totally invisible to detectors. We only detect after-effects of their interactions with nucleons."

So this after efect with the same probability can happen due to very dufferent physical mechanisms that do not involve ilusive particles like neutrinos. May be something in structure of cosmic vacuum cause this efects? Fundamental physical relaity is closed book for us before humans became responsible enough and with willingness to accept the moral standards of the Creator.
TechnoCreed
5 / 5 (6) Jul 25, 2015
@Viko
Ask yourself this; if neutrinos were only a scientific fantasy, would it be possible to send a coded message with them? http://phys.org/n...nos.html , http://arxiv.org/abs/1203.2847
Osiris1
not rated yet Jul 26, 2015
Maybe it will decay into gravitons that compress space that re expands when the gravitons ...move on.
mytwocts
4.2 / 5 (5) Jul 26, 2015

Neutrinos do not interact electromagneticly either.


What are YOU talking about?


He's talking about neutrino's.
He says they do not interact electromagnetically.
He's right.
mytwocts
4.2 / 5 (5) Jul 26, 2015
Creation of an electron or a Muon is an electromagnetic reaction.

No it is not. It is a weak reaction.
mytwocts
4.2 / 5 (5) Jul 26, 2015

So this after efect with the same probability can happen due to very dufferent physical mechanisms that do not involve ilusive particles like neutrinos. May be something in structure of cosmic vacuum cause this efects? Fundamental physical relaity is closed book for us before humans became responsible enough and with willingness to accept the moral standards of the Creator.

You don't make any sense, but sweet little cuddly baby Jesus, you are good at it!

docile
Jul 26, 2015
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mytwocts
4.2 / 5 (5) Jul 26, 2015
The evolution of discussions at PhysOrg resemble the behavior of scientific community at the larger scale - someone (like me) proposes a coherent explanation in many posts,

In science most if not all proposals are rejected. When an idea is unfounded and especially when it is accompanied by unwarranted statements about "mainstream" physics making this mistake and that mistake, without an unassailable analysis to back that up, as is the dominant style at phys.org, then there is little chance that the author will be successful. Otherwise it would become a mess.
But when you have a viable, well explained idea, even without analysis, and it withstands criticism, by all means post it.
mytwocts
4.2 / 5 (5) Jul 26, 2015
If something is made as simple as possible then, logically, it's impossible to make it simpler.

Einstein was just messing with your mind for fun.


Let me explain. By "simpler than possible" Einstein meant "wrong".
docile
Jul 26, 2015
This comment has been removed by a moderator.
viko_mx
1 / 5 (2) Jul 26, 2015
@TechnoCreed

"Fig. 6. Statistic used for synchronization of frames. The open circles identify the locations of
correctly reconstructed frames. Some frames were not correctly found because of accelerator aborts or data acquisition deadtimes"

In fact almost all frames are not corectly catched by detector as can be seen on fig.6. Which raises the question what actually have been captured by the detector. It seems that wishfull thinking related to the desire for regulary funding to the project hinders objectivity. I personally did not find evidence for the existence of a neutrino in this article.
mytwocts
5 / 5 (5) Jul 26, 2015
The simplest theory is that the missing mass of the universe is alternate forms of hydrogen, most likely molecular rather than atomic,

Interstellar and intergalactic hydrogen is observable. Search on "Lyman forest".
Returners
1 / 5 (2) Jul 26, 2015
When future scholars look back at these experiments, they will be embarrassed that their predecessors thought that they were learning about the nature of reality from them.

we might finally create dark matter in the laboratory,


How do you plan to detect it?



OMG LOL.

I have laughed so hard my sides hurt after reading this response.

The amount of psuedoscientific conjecture in the first few paragraphs of this article was so bad that I couldn't help it, I just quit reading the rest of it.

So sad that this is the state of "science".
Returners
1 / 5 (2) Jul 26, 2015
Here's how it will work...

They collide two protons together at ridiculously relativistic speeds. The particles released doesn't quite add up to the energy of the original two protons.

They will say, "Well, we are missing such and such amount of 'mass' from the collision. We believe this means we have created Dark Matter in the laboratory, as it 'must' be there somewhere!"

Cheers...

DM is so non-falsifiable that failure to find it in the particle collider will be considered evidence of its existence by the particle physicists.

The likes of Hawking, Krauss, and Tyson will hail this "discovery" as monumental, and they'll award Vera Rubin the Nobel prize in Physics...for the discovery of ....drum roll... ...absolutely nothing...
Seeker2
5 / 5 (1) Jul 28, 2015
They will say, "Well, we are missing such and such amount of 'mass' from the collision. We believe this means we have created Dark Matter in the laboratory, as it 'must' be there somewhere!"
Happens all the time. The missing matter goes into radiation.

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