Dirk Bertels

The greatest malfunction of spirit
is to believe things (Louis Pasteur)

Higgs Force, the 5th universal force

Last updated 08 September 2012


The discovery of Higgs-like particles at Cern caused quite a stir in the general community. Many people sensed that something important had happened but were unable to come to an appreciatable understanding of the basic concepts involved.

While reading up on this topic many articles might as well have been written in Chinese while others treated their audience with primary school images like wet sponges. An additional nuisance was to be confronted with people's desire to defend their views and personal theories.

In the end, there's nothing like hearing it from those physicists that were at the head of the experiments - as we were lucky to do here in Australia at the Melbourne International Physics conference. Present at this presentation were

  • Prof David Jamieson - university of Melbourne.
  • Prof Albert de Roeck - CMS experiment - university of Antwerp
  • Dr Steven Goldfarb - university of Michigan - ATLAS experiment
  • Dr Raman Sundrum - university of Maryland
  • Prof Young-Kee Kim - Fermilab USA

The following writing has been based on these conference lectures.

Detecting the Higgs Boson

The Large Hadron Collider (LHCD) located 100m underground in Cern, Geneva, Switzerland is essentially a 27km long ring in which protons are accelerated through magnetic fields up to the speed of light. Protons are used because protons, not counterbalanced by electrons as would be the case in an atom, acquire a charge. Magnetic fields can act upon this charge to bring on acceleration. All this is manipulated by 3000 scientists, mostly phycisists, 700 of which directly work with the Higgs experiments.

A big part of the LHC are its detectors. Two of them are very large (larger than your average lecture hall) and are capable of detecting the Higgs Boson: The Compact Muon Solenoid (CMS) detector, headed by Prof Albert de Roeck and the Atlas detector, headed by Dr Steven Goldfarb. Both gave talks at this conference. The results from the experiments at these detectors are held separate, neither one aware of the other's results so as not to influence each other.

An event constitutes the collision of 2 protons travelling head-on at the speed of light. Tens of billions of events have so far been fired, and only about 100 or so are suspected of having created Higgs Bosons.

Using the E=mc2 principle, it is easy to see that since all acceleration is brought to a sudden halt, the enormous amount of energy created in a collision must be converted into mass. Various particles come into existence from a potential (quantum) field of particles. These newly created particles can be much heavier than the initial protons who caused the collision.

Just like there is a table of elements, there is something akin to a table of particles. Scientist can predict which ones will be discovered and what mass they will have. In fact, apart from the Higgs Boson, at least 4 new particles have been discovered, all of which were predicted. The physicists think this newly discovered particle is a Higgs particle because it is within the predicted range of mass which is 125 times the mass of a proton.

The postulation that a Higgs Boson should exist stems from a simple insight. At the moment of the big bang all particles are traveling at the speed of light. So there must have been something that influenced these particles in order to slow them down (and according to E=mc2, consequently acquire mass). This is what Prof Higgs postulated years ago in the early 1950's. At any rate, the maths fitted beautifully.

The word Boson was chosen in honour of the Indian physicist Bose who, with Einstein, played a crucial part in determining the behaviour of at least half of the particles in nature. Bosons are classified as such because they can be put into a special state that creates force fields.

So discovering the Higgs Boson paramounts to discovering a new force of nature. Joining electro-magnetism, the weak nuclear force, the strong nuclear force and gravity there is now also the Higgs force. The Higgs force is a short range force like the weak nuclear force.

Further comments on the Higgs field

  • Higgs particles make up the Higgs field, just as photons makes up the electromagnetic field.
  • The youngest of the forces that were born soon after the big bang were electromagnetism and weak nuclear force that underlies radioactivity. We have very compelling evidence that they fit into an electro-weak unified theory. This unity is partially hidden by an all pervasive field in space, the Higgs field.
  • The Higgs field came into existence in our universe only a few instances after the big bang, as the universe expanded and cooled. Just as water vapour condences into liquid water, the Higgs field condences into the Higgs Condensate.
  • At the big bang, matter and anti-matter (twin species born out of relativity and quantum mechanics) engaged in mutual annihalation, creating pure energy. A tiny sliver survived this, our current universe. So what tipped the balance? It may well be the process of Higgs condensation that tipped the balance.

Relationship between mass, gravity and Higgs field

  • There are 2 main aspects to particle physics: interaction and propagation. Looking at the propagation of particles, mass determines how fast you can travel given a certain amount of energy. That's what mass is to a relativist.
  • Higgs field is responsible for giving all the particles their mass, except for dark matter [and neutrinos?]
  • Gravity responds to mass (Gravitons are also Bosons).
  • Gravitons and Higgs Bosons don't seem to be related.

What next + some research ideas

  • It is possible that we can use the Higgs force to catch dark matter, which is not made of the electrons, protons and neutrons that our known matter is made of.
  • The mass of the Higgs Boson suggests an even grander unification. the unification of electromagnetism, weak nuclear force and strong nuclear force, occuring at an earlier instance after the big bang.
  • The mass of the Higgs Boson is vagely troubling to supersymmetry (which conjectures a suggested addition to the grammar of quantum mechanics and relativity).
  • The mass is opportune for studying new types of physics, since the particle decays in a number of different ways.
  • String theories have ideas that unifies the forces, though experimentally not verifiable at this time.

Some notes on Particles in general

  • The true significance of particles lies within their collective behaviour. There is even a kind of family tree that seems to be emerging. The grammar of particle physics is given by quantum mechanics and relativity.
  • every second, a trillion neutrinos zip through your body.
  • neutrinos are a million times lighter than electrons
  • origin of neutrino mass is still unknown.