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I would really like to understand Higgs-Englert’s discovery that earned them the 2013 physics Nobel prize. I tried reading their work, but understood nothing of it unfortunately.

The reason why I’m asking here is because, unfortunately, it is very hard to find physics principles explained in such a way that a non-physicist can understand them. Either the explanations are far too simplified and/or incomplete, or they require a lot of prior knowledge and/or ask you to accept certain concepts that most of us would find unusual or unnatural.

I’m a mechanical engineer. As such, I have a basic understanding of physics, but no way near enough to understand Higgs-Englert’s work. I have many friends and colleges in the same situation as I am who would also like to understand what has been discovered, how, and why it’s important.

Therefore, could someone provide a simple, but complete and thorough explanation of this work? Preferably including explanations of the basic concepts/principles it makes use of.

David Z
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Percy
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    Look at the Higgs articles on Matt Strassler's blog - http://profmattstrassler.com/ – John Rennie Oct 09 '13 at 16:31
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    Possible duplicates: http://physics.stackexchange.com/q/6450/2451 , http://physics.stackexchange.com/q/17944/2451 and links therein. – Qmechanic Oct 09 '13 at 16:39
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    "Therefore, could someone provide a simple, but complete and thorough* explanation of this work?" The simple answer is: no. You can have a simple explanation of this work or* a complete and thorough explanation. If you're after a complete and thorough understanding of this work (why else would you want a complete and thorough explanation?), you've got some homework to do. – Alfred Centauri Oct 09 '13 at 18:02
  • Matt Strassler's what if higg-field were zero is good introduction. – user6972 Oct 09 '13 at 18:07
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    This question in particular is very close to being a duplicate, I think, but I don't know that it is actually an exact duplicate. – David Z Oct 09 '13 at 18:59

3 Answers3

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In few words:

All the data gathered on particle physics can be beautifully classified in what is called the Standard Model. It is based on group symmetries in the behavior of particles, three groups two of them special unitary groups and one a simple unitary group. 

     SU(3) x  SU(2) x U(1)
     strong    weak electromagnetic

each group representing one of the three forces as labeled above.

What does this mean? It means that all the elementary particles can be found as a member of an irreducible representation of these combined groups, the quark model classification finds its mathematical justification.

an example of an SU(3) group representations is the baryon octet, where the quantum numbers of the particles allow them to be entered in the octet representation of an SU(3) group.

octet

Figure 4. The S = 1⁄2 ground state baryon octet

The mathematical unification of the three forces when expressed in the proper lagrangian formalism, is on the basic elementary particles in the table: the quarks, the leptons and the intermediate force carriers, photons and gluon and W/Z. In the first version of the model the masses were zero if the symmetries were to be respected mathematically, whereas the real particles had masses .

It was necessary to find a way to give masses to the elementary particles and that way was found by the Higgs mechanism, which broke the symmetry in such a way as to allow for the appearance of masses for the particles.

Another plot for symmetries shows the Higgs field breaking the symmetry:

symmetries and higgs

The pattern of weak isospin, T3, weak hypercharge, YW, and color charge of all known elementary particles, rotated by the weak mixing angle to show electric charge, Q, roughly along the vertical. The neutral Higgs field (gray square) breaks the electroweak symmetry and interacts with other particles to give them mass.

The Higgs mechanism permeates all space, it is a field. Nevertheless, when included into the mathematical equations defining the Standard Model a prediction was made: There should be a particle with a fixed mass, which is the Higgs found at CERN, which would not be there if the Higgs mechanism were nonexistent.

Thus the particle found at CERN confirmed that the Higgs mechanism is at work and real, breaking the zero mass symmetry and giving masses to all paraticles, including the Higgs particle itself.

The mathematical formulation and solutions of the Standard Model Lagrangian is something one could study in a semester course. If you look at the link, it isn't that simple to be discussed on this board.

anna v
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Have a look at Prof Susskind's video, Demystifying the Higgs Boson. There are other videos in mechanics, relativity etc as part of the course.

Larry Harson
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I think this link explains it in a very simple way for a non-physicist. For a more detailed explanation (you don't need to be a professional physicist to understand it) watch this. Particularly from minute 10 to minute 40.

Hopefully that is what you are looking for!

Gotaquestion
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