
What is the Higgs? - subsystem
http://www.nytimes.com/interactive/2013/10/08/science/the-higgs-boson.html
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yk
(Sorry for ranting instead of explaining, but I do not have much time at the
moment.)

I really hate this molasses explanation of the Higgs field. The problem is, it
is wrong, suggests a wrong intuition and obstructs actually interesting
physics. It is wrong, because the mass is something very different from
friction. It suggests a wrong intuition, because the snow field, or the
molasses, generates a force when something is moving through the medium. But
there is no medium to move through. ( And mass acts, when there is a change of
velocity, friction if there is velocity.) And the last point, the Higgs
mechanism is a mathematical manipulation, which gets a term into the
equations, that looks exactly like a mass term would. ( But without breaking
electro weak symmetry.) There is really a lot of interesting physics going on
here. The most fundamental question is probably, what is the relation between
reality and physical models. If in one model the Z boson is massive, and in a
equivalent model the Z boson is massless, but both models agree on every
quantitative prediction. In which sense can we say that the Z boson is
massive?

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saraid216
Not being a theoretical physicist whatsoever, the last thing I understood in
this comment was "It suggests the wrong intuition".

It's super that there's a lot of interesting physics going on here, but you
haven't explained _any_ of it in a way I can understand, and I'm half-decent
for a layman. (I don't quite understand basic quantum mechanics yet, for
instance.)

I sympathize with the problem of bad analogies providing incorrect intuitions.
That's a problem in popularizing science, especially cutting-edge science. But
you're not going to make any headway against these inaccuracies unless you
push against the door from the other side with _correct_ intuitions.

~~~
yk
I am actually not sure what a good explanation would be. The problem is to a
large part, that the particle explanation for high energy physics offers no
good analogy. ( You will often hear that a photon is exchanged between
interacting particles, with the implicit understanding that a photon is
something like a billiard ball.) But perhaps I can at least describe the
problem better.

The way physicists currently construct theories is based on mathematical
symmetries. And in particular the theory of the electro weak interaction is
build on a symmetry between the electro magnetic force and the weak force. So
this gives the prediction that the weak force should be similar to the electro
magnetic force, especially that it should have infinite range. But the
experimental observation is, that the weak force acts only on very small
distances, usually less than a femto meter.

The solve this problem, Peter Higgs noted that the symmetry between
electromagnetism and the weak force should exist in the lofty world of
mathematics, while in the messy real world the symmetry is broken somehow. So
he invented a additional field, which breaks the symmetry. This is somewhat
similar to the claim, that a car can go in any direction (the symmetry), but
in realistic situations all cars follow the same road. So the road breaks the
symmetry, without taking anything away from the ability of the car to go in
any direction.

In quantum field theories forces correspond to particles. And the particles
associated with the weak force, W and Z bosons, should therefore be similar to
photons, the particles associated with electro magnetism. But a force that
acts only on small distances means that the field quanta are massive, unlike
photons which are massless. So in this view, the Higgs mechanism adds mass to
the W and Z bosons, but does not add mass to the photons. But a better
explanation would probably be, that the Higgs field limits the range of the
electro weak force to the experimentally observed short distances.

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kachnuv_ocasek
Back in 1993 there was a competition whose target was to explain the Higgs in
one page of text. I found these very enlightening as well. Here are the
winners:

[http://www-cdf.fnal.gov/~bernd/higgs/](http://www-cdf.fnal.gov/~bernd/higgs/)

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ChrisArchitect
great link, neat to read the various approaches.

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InclinedPlane
The best explanation of the Higgs mechanism I've seen so far has been from
"minute physics":

Part 1:
[http://www.youtube.com/watch?v=9Uh5mTxRQcg](http://www.youtube.com/watch?v=9Uh5mTxRQcg)

Part 2:
[http://www.youtube.com/watch?v=ASRpIym_jFM](http://www.youtube.com/watch?v=ASRpIym_jFM)

Part 3:
[http://www.youtube.com/watch?v=6guXMfg88Z8](http://www.youtube.com/watch?v=6guXMfg88Z8)

(If you only watch one part, watch part 2, it's only 170 seconds long.)

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davrosthedalek
Nicely made, however most visible mass (i.e. the mass of protons/neutrons) is
generated dynamically by the quark interactions.

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gibybo
I have a basic understanding of electrons and the electric field. Can I think
about a Higgs particle like a particle with a mass charge? Does the field work
similarly to the electric field? Do all particles with mass have a Higgs
particle in them?

~~~
cshimmin
To answer your questions: 1) sorta. "mass charge" is just mass. In quantum
field theory, particles can have an intrinsic mass parameter. The higgs mass
parameter is interesting in that it is imaginary (i.e. its value squared in
negative).

2) Not really. In quantum field theory, the fundamental spacetime entity is a
field, and quantized excitations of the field are interpreted as particles. So
the "Higgs field" is just a postulated field in spacetime, which is associated
with the observable particle called the Higgs Boson.

3) No. Roughly speaking, the mathematical mechanism by which the Higgs "gives
particles mass" is like this: You write down the theory with the Higgs
particle doing its own thing; it turns out this theory can be "viewed" from
different perspectives (physicists refer to this as a gauge). If you view the
theory from a certain perspective (see: spontaneous symmetry breaking), the
algebra of the equation gets all jumbled up. When you untangle the equation by
factoring etc, you get back to something that looks like a physics theory, but
now the Higgs got mixed into various places in the equation. In some places,
it looks just like a "mass charge". This mechanism was originally proposed to
get around a nasty problem in physics; our super-awesome theory of electroweak
interactions was _very_ clear that the weak bosons (W and Z) _must_ be
massless. But when we discovered these particles they were really heavy. The
Higgs mechanism is a loophole that allows these bosons to be formally massless
in the theory, but which get mixed with the Higgs to give an observable mass
as described.

The whole idea of a field having "imaginary mass", and that our universe could
be in a spontaneously broken vacuum state (i.e. that we're viewing the theory
from a weird perspective) are pretty hard to swallow. This is while the
discovery of the Higgs boson is a _huge_ vindication for theoretical physics;
it puts all these crazy-sounding ideas on empirical footing.

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Le_SDT
Very good presentation for someone like me with no knowledge in physics but
still facinated by all those discoveries! :) Thanks

~~~
gueno
+1 much more "understandable" with the metaphor of snow

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ssivark
That's a very nice illustration.

If you'd like a quick read, here's an "elevator pitch" explaining the Higgs
mechanism/boson -- [http://dickfeynman.ruhoh.com/physics/higgs-for-
laypeople/](http://dickfeynman.ruhoh.com/physics/higgs-for-laypeople/)

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geldedus
Higgs boson, not the Higgs

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khuckzz
The animation and illustrations are cool but I still have no idea what a Higgs
is.

