What is the Higgs Boson?

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July 11, 2012 Tags: Earth, Universe & Time

Today's entry was written by Gerald Cleaver. Please note the views expressed here are those of the author, not necessarily of The BioLogos Foundation. You can read more about what we believe here.

What is the Higgs Boson?
The image above shows three virtual views of an event recorded by CERN’s ATLAS detector on 18-Jun-2012. Muon tracks are colored red, electron tracks and clusters in the LAr calorimeter are colored green. The larger inset in the upper right shows a zoom into the tracking detector. The smaller inset lower right shows a zoom into the vertex region, indicating that the 4 leptons originate from the same primary vertex. ATLAS Experiment © 2012 CERN

At a press conference on July 4, 2012, and with 99.99994% confidence (5 sigma), CERN announced the discovery of a particle consistent with that of a Higgs boson (a.k.a. “the God particle”). This is very exciting for elementary particle physicists. It is also getting the attention of press and general public. But what is the Higgs particle, and what is its meaning?

It has been widely reported that the moniker “God particle” was not its originator’s first choice. Still, Leon Lederman, director emeritus of Fermilab and Nobel laureate for neutrino research, did accept the nickname “God particle” because the particle is “so central to the state of physics today, so crucial to our final understanding of the structure of matter, yet so elusive.” “God particle” was quickly accepted by the press and general public because it seemed an appropriate title for a particle theorized to give mass to all elementary matter particles and the force carrying W and Z bosons. Serving this mass-giving function since near the beginning of the universe, a Higgs field (more fundamental than the actual Higgs boson ) must necessarily exist everywhere in the universe and be unchanging. With an omnipresent and immutable field, analogies between the Higgs boson and God naturally developed within the press and the public—“God particle” became deeply rooted. Relatedly, the Higgs boson become an excellent source for theological analogies. (See for example this article.)

Nevertheless, as physicists seek to emphasize, neither the Higgs boson particle nor its field have religious properties. Thus, elementary particle physicists are not fond of the “God particle” appellation. In the opinion of Oliver Buchmueller, of CERN’s CMS group, calling the Higgs boson the “God particle is completely inappropriate. It’s not doing justice to the Higgs and what we think its role in the universe is. It has nothing to do with God“. As Pippa Wells, another CERN scientist expressed, “Calling [it] the God particle … confuses people about what we are trying to do at CERN”. (Source: Reuters)

One alternate name for the Higgs particle that is used within the physics community is the “BEH” particle. “BEH” stands for Brout–Englert–Higgs, three of the six authors of 1964 papers that first proposed a mechanism for giving mass to elementary particles. In addition to Peter Higgs, the five other authors are Robert Brout and Francois Englert, and Tom Kibble, C.R. Hagen, and Gerald Guralnik. The process for giving mass to particles is thus sometimes referred to not just as the Higgs mechanism, but as the Brout–Englert–Higgs–Hagen–Guralnik–Kibble (BEHHGK) mechanism. (Saying all six names a couple of times makes it obvious why we most often only call it the Higgs.)

But issues of naming aside, what is the Higgs and why is it so elusive? According to the Standard Model, the particles that compose matter (the quarks and leptons) are in a category called spin-1/2 particles. The force carrying particles (the photon, the W's, the Z, and the gluons) are spin-1 particles. What the physicists above proposed was the existence of a type of spinless, or spin-0 particle. Not only does the Higgs boson form its own class of particles, it also gives mass to itself and to all the other particles that have mass: to all of the leptons and quarks, and to the W's and Z bosons, but not photons or gluons. This set of relationships is shown in the image below, indicated by the lines connecting the Higgs to these other particles. There are no lines directly connecting the Higgs boson to photons and gluons because the Higgs boson does not interact with these force carrying particles and, thus, photons and gluons remain massless.

But the story of the Higgs particle actually begins with the associated Higgs field, an invisible field (something like a generalization of an electric field) that has a non-zero, constant value everywhere throughout the universe. This Higgs field continuously interacts with all matter particles and the W and Z force carrying particles. Matter and massive force particles are slowed down as they move through the Higgs field, just as are balls rolling through thick mud. The Higgs field is sometimes described as a “cosmic molasses”. Different particles interact with the Higgs field to varying degrees—those interacting more, are slowed down more, those interacting less are slowed down less. Slowing down more equates to acquiring more mass. If not for the Higgs field, all particles would be massless, zipping through the universe at the speed of light. The universe would be without structure—no galaxies, no plants, no life. Without the Higgs field, not even atoms could have formed.

It should be noted, however, that the majority of the mass of protons and neutrons (and thus of atomic mass) does not come from interaction with the Higgs field. Each proton and neutron is composed of three quarks, which do receive their mass from their interaction with the Higgs field. However, the masses of protons and neutrons are much greater than the sum of their constituent quarks and are a result of the additional mass contribution from the binding energies of the “trapped” quarks.

It was theoretically possible for elementary particles to have mass without needing to acquire it through interaction with a Higgs-like field. However, as the standard model of elementary particles developed in the 1950’s and 1960’s, elementary particle theorists realized that if particles had their own innate mass, rather than acquiring it, many beautiful symmetries of particle interaction equations would be broken. To keep the beauty and symmetry in the theory was the essential reason the BEHHGK mechanism was developed, which immediately led to the prediction of Higgs bosons.

When there is enough external energy in a given volume, the Higgs field also produces Higgs bosons. But the Higgs bosons are very unstable and quickly decay. This is the process that enabled the discovery of the Higgs boson at CERN. At CERN, protons are accelerated to high energies via electric fields and directed in circular paths via magnetic fields. The protons then collide and release large amounts of energy. When sufficient energy is released in a collision, the Higgs field can use this energy to produce Higgs bosons. The Higgs bosons quickly decay leaving evidence of their existence through particular combinations of leftover particles that they have decayed into. Among those predicted by the mathematics of the Standard model are the muons and electrons identified by the CERN experimenters. The image at the top shows the identities and paths of particles produced in one of the CERN proton-proton collisions whose results fit with what would be expected from the decay of a Higgs boson.

For a proton-proton collision at the CERN LHC, the above diagrams show both the dominant modes for creation of a Higgs with a mass around 125 GeV, and the two dominant decay channels (modes). The creation mechanism (shown schematically in the left half of each diagram above) involves virtual gluons, the carriers of the strong nuclear force (represented by squiggly purple lines) from the protons. The gluons fuse into a virtual top quark loop (medium blue triangle), which then emits a Higgs boson (squiggly yellow line). The top quark couples more strongly to the Higgs than any of the five other quarks, so the top quark contributes the dominant loop.

The Higgs boson then dominantly decays into either (i) 2 gamma ray photons (the squiggly green lines) via another intermediate virtual top quark loop or a virtual W gauge particle loop (dark blue triangle), or (ii) two Z0 gauge particles (squiggly dark blue lines), which each then decay into a lepton (specifically an electron or a muon)/anti-lepton pair (light blue lines).

The likely discovery of the Higgs boson, and its implied existence of the associated Higgs field, is an amazing success for CERN. Past research and experience at Fermilab and by elementary particle physicists throughout the world also contributed to the discovery. The Higgs boson was the remaining particle in the Standard Model of Particle Physics to be found. With it, the Standard Model is in some sense complete. (Nevertheless, many questions about the Standard Model still remain—many inspired once again by beauty and symmetry. In particular, several numeric values associated with particle masses and interactions could only be experimentally measured, as with the Higgs, and not predicted from the Standard Model.)

With the apparent success of these experiments and seeming confirmation that the physical universe is, indeed, reflected by the complex and beautiful mathematics of the Standard Model, the international physics community is eager to keep delving deeper into the structure of creation. In addition to trying to verify that the 125 GeV particle is, indeed, the Higgs spinless particle and not some more exotic, new particle, CERN physicists are simultaneously seeking to discover an entire new class of particles, resulting from a theorized symmetry called supersymmetry. Discovery of the associated particles, if they exist, will likely take a few more years. For these discoveries we can only wait in anticipation.



Updated July 12, 2012.


Gerald Cleaver is an Associate Professor of Physics at Baylor University. He is a member of the Physics Department's High Energy Physics group and also heads the Early Universe Cosmology and String Theory division of Baylor's Center for Astrophysics, Space Physics, and Engineering Research. Gerald earned his Ph.D. at Caltech in 1993, where he studied under John H. Schwarz, one of the founders of string theory. His research interests focus on elementary particles, fundamental forces, and superstring theory. His hobbies include radio-controlled model aviation, small-boat sailing, and tae kwon do.


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George Bernard Murphy - #71041

July 11th 2012

“But the story of the Higgs particle actually begins with the associated Higgs field, an invisible field (something like a generalization of an electric field)”

True but the Higgs field has no know source generating the field.

A magnet field is generated from a magnetic pole.

 And an electro magnetic field is generated from a magnetic pole.

 Where the Higgs field arises nobody knows.

 But I think the believe it was the first thing created.


George Bernard Murphy - #71042

July 11th 2012

Excuse my I meant to say an electric field is generated by an electric charge.


wesseldawn - #71057

July 12th 2012

This is a well written and easy to understand article on the complicated topic of physics. The discovery of the Higgs Boson then is really a giant leap for physics!

The world of particle physics reminds me somewhat of the world of biology where electron microscopes discovered a whole other world of micro organisms.

It seems to be a rule of this world that the smaller we go, the bigger we get - as if the universe is really inverse.

 


Francis - #71058

July 12th 2012

What is the Higgs Boson?

Among other things, it’s something that took 30 years and cost at least $10 billion to find.

Maybe someday they’ll find a use for the Higgs boson – like a better microwave oven or a more powerful bomb. I have my doubts.

$10 billion could provide a lot of clean water and mosquito nets for the millions of human beings dying every year from cholera, dysentery and malaria.

Well, at least we have some nice new particle physics charts.

 

P.S.

Typo correction needed by BL editors: “eager to keep devleing deeper”


wesseldawn - #71091

July 14th 2012

“The Higgs boson was the remaining particle in the Standard Model of Particle Physics to be found. With it, the Standard Model is in some sense complete”

I think if you were a particle physicist, this discovery would be an exciting one! As I understand it, the implications for future physics are profound.


HornSpiel - #71059

July 12th 2012

Thanks for the nice explanation of a Higgs boson and field. Glad you did not dwell on the “God particle” hype. There was a lot of good information here I had not heard from other news sources. I particularly found this sentence enlightening: “When there is enough external energy in a given volume, the Higgs field also produces Higgs bosons.” Kudos.

However, I am intrigued by the note in the sidebar—”However, the masses of protons and neutrons are much greater than the sum of their constituent quarks and are a result of the additional mass contribution from the binding energies of the ‘trapped’ quarks.” Would love a bit more explanation about that.

Also what is the relationship between the Higgs particle and the so-called Graviton, the carrrier of the gravitational force?

 


George Bernard Murphy - #71061

July 12th 2012

Well energy can be converted into mass.

 The formula is e=mc2 .

A young gentleman named Al Einstein declared that in the early part of the 19th century.

Energy from the strong nuclear force is required to bind proton together and energy is required to bind quarks into protons.

 [Releasing some of this energy is what makes an  atomic bomb explode!]


George Bernard Murphy - #71062

July 12th 2012

You cannot find the graviton anywhere in the standard model.

That is why string theory and particularly M-theory may replace the standard model.

 The graviton pops right out of those formulas.


John Moes - #71089

July 13th 2012

“I particularly found this sentence enlightening: “When there is enough external energy in a given volume, the Higgs field also produces Higgs bosons.”

I found the sentence puzzling. The Higgs field in a given volume? What is the “volume” and where did it come from? Where did the Higgs field come from? And they needed a huge amount of energy to produce the Higga boson that slowed energy down enough to squeeze the energy into bundles of massive energy - that don’t stay in masses?

That sentence needs some elaberation. It still seems to require something eternal or an uncaused cause.


George Bernard Murphy - #71090

July 13th 2012

Well to relate it to creation as described in Genesis  the Higgs field was the first thing created in Genesis.

 The Bible says the  universe was “without form”

   “but the spirit of God hovered over the surface of the waters” 

 In my opinion TTHT WAS WHEN GOD DESIGNED WHAT WE NOW CAL “THE STANDARD MODEL. 

HE SET THE STRENGTH OF GRAVITY.

 Hawking has said that at any other value for gravity the universe could not exist.

“GOD HOVERED OVER THE SURFACE OF THE WATERS”.

 

REMEMBER THAT!


wesseldawn - #71105

July 15th 2012

What are the waters?

“And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters.” (Genesis 1:6)

“And God made the firmament, and divided the waters which [were] under the firmament from the waters which [were] above the firmament: and it was so.” (Gen. 1:7)

There are clealry two waters: the waters above the firmament and waters below it!

 


George Bernard Murphy - #71114

July 15th 2012

Wess I think Day 2 of creation, when God created an “expanse” separating the “Waters” was about what is now called “cosmic inflation”.

 The uiverse suddenly expanded at a very rapid rate.

 The author of this idea is Alan Guth who conceived the idea in about 1970.

 [I have some personal prejudice against Guth because he seems to bash people of faith but his cosmic expansion idea waas great] 

The universe started as a point smaller than a proton.

It was made of something very hot but there were no particles an no fundamental forces, but seemingly the law existed that nothing within the universe could move faster than the speed of light.

Suddenly the universe began to expand at a rate much faster than tthe speed of light.

SO THE CONTENT OF THE UNIVERSE COULD NOT EQUILIBRATE.

THE DISTRIBUTION OF THE HOT GAS BECAME UNEVEN. The Gravy became lumpy, And it stayed that way.

 The lumps from that tiny ball  are the same, [planets ,galaxie etc] ,.. that we have today.

 The  lumps themselves were created by gravity consoliating matter so actually is was the SPACES that were the blue print for the design. The word “firmament” is not in the original text.

 I think the original word was “Raqua” which refers to hammered brass.

Reflect for a moment! When you hammer brass you produce THIN PLACES.

God designed the universe by producing THIN PLACES.

 Gravity did the rest.


wesseldawn - #71106

July 15th 2012

 


wesseldawn - #71107

July 15th 2012

Sorry I can’t seem to insert Strongs translation page but if you look up the word ‘firmament’ at BlueLetterBible.org you will read that the Jews believe that above the universe there is a heavenly ocean. Clearly the verses I quoted (and and there are many more) agree with that interpretation.


George Bernard Murphy - #71115

July 15th 2012

Look up “Raqua”

The ancient Jews were clearly wrong about that “heavenly Ocean”.

Alan Guth AND THE ACTUAL BIBLE,.. are right.


George Bernard Murphy - #71116

July 15th 2012

Strong ain’t scripture!


wesseldawn - #71120

July 15th 2012

At some time the ‘waters’ were divided: the waters ‘above’ the firmament and the waters ‘below’ it - meaning two kinds of waters!!

The waters below are obviously ‘cosmic expansion’ but what are the waters above?

And what caused the division in the first place?

You don’t consider Strong’s an authority (list of scripture verses, which is scripture) but you will have me look up Raqua, which is not scripture!!  Is Raqua your spiritual authority then?


George Bernard Murphy - #71124

July 15th 2012

The waters are not the expansion.

 The expansion separates the “waters  so that there a"waters” above and below the expansion.

This hot plasma was difficult to separate  so that this “expansion” of the stuff that contituted the early universe was a miracle.

Fuids and gasses expand immediately to fill empty space so they instantly redistribute evenly through out the space available.

How do you create an empty space in a glass of tea,.... a place where there is no tea?

 Well you could stick your finger into the tea but if you withdraw your finger from the tea the space will filli imediately.

[In fact here is an ancient folk-saying that “the only essential person in any organiation is the man who can stick his finger into a cup of coffee and leave a space there when he pulls his finger out.”]

But God created permanent spacees within the hot plasma of the early universe.

 It is a difficult thing to do. No one has ever done it.

 GRAVITY DID THE REST.

BUT WITHOUT THE SPACES, GRAVITY WOUD HAVE PULLED THE UNIVERSE BACK INTO A SINGULARITY.

BUT BECAUSE THE SPACES WERE THERE GRAVITY FORMED OUR UNIVERSE.

Nobel prize winer Dr. George Smoot has a video thowing this on Youtube,,.... and the pattern is tracable in the  microwave bckground radiation as mapped by the COBE and Wilkenson satellites.


George Bernard Murphy - #71125

July 15th 2012

http://www.youtube.com/watch?v=c64Aia4XE1Y

 

HEre is the George Smoot video onhow gravity formed te universe.

 It is 19 minutes long BUT THIS GUY WON THE  THE NOBEL PRIZE FOR WORK ON THE VERY SUBJECT WE ARE DISCUSSING.

HE ALSO SAID  WHEN HE FINISHED THAT HE HAD SEEN GOD’S BLUEPRINT BUT HE WAS BADGERED INTO WEAKENING THAT STATEMENT.

I THINK HE STILL BELIEVES IT THOUGH.


George Bernard Murphy - #71128

July 15th 2012

And if you liked that video try this one

http://www.youtube.com/watch?v=YtdE662eY_M&feature=relmfu

God created ALL OF THIS STUFF.


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