The
God(less) particle
The Higgs boson is named
after Professor Peter Higgs, who proposed the mechanism that
suggested such a particle in 1964. -- PHOTO: REUTERS
Andy Ho
SENIOR WRITER
THE scientific world was abuzz last week with the "God
particle".
Or, at least, that was how the world media hyped it up.
Scientists at Europe's US$10 billion (S$12.7 billion) Large Hadron
Collider called a press conference to announce their discovery of a
subatomic particle called the Higgs boson.
A Nobel laureate in physics decades ago gave it this
evocative name, which scientists now hate. But the legions of
non-physicists who logged in to follow "live" the online streaming
of their press conference on July 4 must have largely been
attracted by this moniker.
Let's be honest about it: few non-physicists would have
bothered with a press conference about bosons, fields and "five
sigma", terms that featured liberally in the proceedings.
To be sure, it was a significant finding. And since Big
Science requires Big Money, the media coverage will work wonders
for its funding in Europe. Legislators will now be suitably
intimidated by (their lack of understanding of) the God particle to
suggest reducing Collider funding any time soon.
Trouble is, there isn't anything particularly "godly"
about this particle. So what is the Higgs particle?
To explain it requires some backgrounding. The concept of
that seeming emptiness we call "space" actually contains fields
invisible to the eye, like electromagnetic fields and gravitational
fields. Every point of space said to be empty contains these
fields.
Particles are packets of energy which interact with one
another and with space (fields). When particles interact with
fields, there is exchange of energy, which can be transformed into
particles with or without mass.
This exchange of energy occurs through the agency of
something called the exchange particle. For example, you may recall
from high school science that when electrons orbiting an atomic
nucleus drop from a higher orbit to a lower orbit, a photon - which
is a massless particle or packet of light energy - is emitted. When
a photon collides with and absorbs another, an electron can jump up
to a higher orbit. Thus the photon is an exchange particle of the
electromagnetic field.
All exchange particles are species of what is called a
boson particle. The Higgs particle is one type of such a boson.
Scientists came up with a theory that such a particle must exist,
in order to explain why some particles like photons have no mass
whereas others like protons and electrons which make up matter do
have mass.
Using their best model called the standard model,
physicists can describe every kind of particle in the cosmos and
how large their masses should be, including no mass. But the model
cannot explain why mass should exist at all.
To get around this, physicists postulate that there is
something called the Higgs field in "empty" space that produces
mass. If particles (like neutrinos) moving through this field can
interact with it, the "drag" gives rise to mass. If particles (like
photons) moving through a Higgs field cannot interact with it, then
they won't have mass.
Now all you have to do is prove that Higgs fields do
exist.
Using the standard model, physicists know the mass that a
Higgs boson must have - if it exists. If you detect Higgs bosons of
this precise mass, then you would have proven that Higgs fields do
exist. This is what the European scientists said on July 4 that
they had achieved.
How is the Higgs boson related to the Higgs field? It's
somewhat akin to the relationship between the pattern of vibration
of a guitar string to the string itself. To find out how tightly
strung up the string is, just pluck it, and the sound (waves)
emitted will tell you so. Likewise, to know about the Higgs field,
collide one proton with another as they did at the Collider and
study the waves that result, which are Higgs bosons.
Because such collision data is very complex, errors creep
in very easily. To be sure that a particle's mass detected is that
of a Higgs boson and not random statistical chance, scientists use
a measure called sigma. One sigma means there is a 32 per cent
chance that your results are due to happenstance and not the real
phenomenon. Two sigmas equal about 5 per cent chance your data is
not real. This drops rapidly so that at five sigmas certainty, you
are 99.999 per cent sure you have really found what you were
looking for, that your results did not occur by random chance. This
is what the Collider scientists declared recently, that their data
was five sigmas sure to be correct.
So they were almost 100 per cent sure they had found the
Higgs boson, which proves that Higgs fields do exist. And this, Dr
Lawrence Krauss, a theoretical physicist at Arizona State
University says, explains how all mass and matter came into
existence out of nothing since space is nothing - though it really
contains fields.
In his recent book, A Universe From Nothing (2012), Dr
Krauss, like many in the field, explains that the Higgs field
permeates all of space and brought into existence, through the
Higgs boson, the stars, planets and people. Some may consider it
the "God particle" for explaining how mass formed. But Dr Krauss
views it as the "God-less" particle that would explain the
existence of everything without a Creator.
If we live and move in a universe that came out of
nothingness, the meaning of life changes radically and all religion
is claptrap, Dr Krauss asserts.
Yet proving that Higgs fields exist (because you have
proven Higgs bosons do), thus explaining how mass came into being,
simply pushes the question back one step. We now must ask: "Why
were there Higgs fields - and particles - there in 'empty' space in
the first place?"
But Dr Krauss takes for granted the laws of quantum
mechanics, which Higgs fields have to obey and do obey for mass and
matter to come into existence. He only alludes to these laws of
relativistic quantum field theories in passing in the last few
pages of his book. He does not ask where those laws that govern
what arrangements of quantum fields are possible and which aren't
come from.
Did some other property - animate or inanimate - give
rise to those laws or to the fact that the universe is made up of
particular kinds of fields? So the Higgs boson discovery does not
prove creation from nothingness. Nor, of course, does it prove the
existence of a Creator, despite the media dubbing it the God
particle. What it proves is just that mass comes from Higgs fields,
which is a long way from proving whether there is a Creator or
not.
Opinon, The Straits Times, Wednesday, July 11 2012, Pg A24