The Large Hadron Collider (LHC) is one of the most ambitious science project to date, rivalling that of the space project to sent humans into outer space. Costing an enormous US$6 billion to build (for comparison, the space shuttle Endeavour cost only US$1.7 billion, and the NASA Mars Project is US$1.2 billion), it boggles the mind that the main purpose of its construction is to determine the existence of an infinitesimally minute elementary particle called the "Higgs Boson".
More photos of the LHC at http://www.darkroastedblend.com/2008/03/time-machine-worlds-biggest-particle.html
There is a very engrossing talk by Professor Brian Cox about the LHC. It compresses in 20 minutes a presentation of the best scientific explanation of "what the universe is", and why the LHC is such an important project. I am sure you will enjoy this talk:
http://www.ted.com/index.php/talks/view/id/253
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If you need a primer of what is a "Higgs Boson" particle, here is my simplified explanation:
Back in my early school days, I was taught about how all matter is composed of atoms. In fact, the theory of atoms being the fundamental building block of matter was first written by the ancient Greeks back in 400 BC.
However, in the late 19th century, scientists discovered that the atom is not the most fundamental particle (a fundamental particle is a subatomic particle that is not composed of any other subatomic particle). Instead, they found that atoms were composed of electron particles orbiting a nucleus containing protons and a neutrons.
This is probably the level of science that most of us were taught up to in secondary school.
In the mid-20th century, scientists discovered that while electrons are fundamental particles, protons and neutrons were not. Protons and neutrons are composed of an even smaller particle called the quark.
Quarks never exist alone. They are always found in groups of other quarks. A composite particle made of several quarks is known as a "Hadron", which is what the LHC (Large Hadron Collider) is named for.
Thus, the scientists now have 2 fundamental particles: the quark, and the electron.
Unlike the quarks which always exist in groups (you always find quarks in groups of two or three quarks), the electron is always alone (they are said to be solitary particles). However, scientists found that electrons were not the only solitary particle. Besides the electron, scientists found other solitary particles like the muon, the tau, and the neutrino. Scientists categorised these solitary particles as "leptons".
So basically, matter is made of the fundamental particles of quarks and leptons.
(There is actually another group of fundamental particles called "anti-quarks" and "anti-leptons", which are the components of "anti-matter". However, I will not discuss anti-matter in this explanation).
But how do protons and neutrons bind themselves together in the nucleus? Why do magnets attract iron nails? Why do uranium decay, (causing harmful radiation in the process)? Why does the Earth revolve around the Sun?
All these actions are actually forces that are exerted by particles on other particles. Scientists identified 4 kinds of forces, mainly:
Strong Nuclear force (the force that binds protons and neutrons in the nucleus of an atom)
Electro-Magnetism force (the force that allows a magnet to attract iron nails)
Weak Nuclear force (the force that causes radioactive decay)
Gravity (the force that stops us from falling into space)
To explain how particles exert this forces on each other, scientists proposed another form of particle called the "force-carrier particle" that interact between quarks and the leptons. The force-carrier particles for each of the 4 forces are:
Gluon : Strong Nuclear force
Photon : Electro-Magnetism force
W+, W-, Z : Particles for the Weak Nuclear force
Graviton : Gravity
In summary, matter is basically composed of quarks, leptons, and force-carrier particles.
Now, quarks and leptons are "space occupying particles". For example, two quarks cannot share the same "space".
However, force-carrier particles do not behave in the same way. For example, 2 or more photons can share the same "space".
Scientists classify "space occupying particles" as fermions, and "space sharing particles" as bosons.
Thus, all quarks and leptons are fermions, while all force-carrier particles are bosons.
The "Higgs Boson" is a force-carrier particle that that has been predicted by the mathematics of particle physics, but has not been physically observed. If found, it will provide the explanation of why particles acquire mass!
If you are interested in learning more about particle physics, I can't recommend enough the following site:
http://particleadventure.org/index.html
More photos of the LHC at http://www.darkroastedblend.com/2008/03/time-machine-worlds-biggest-particle.html
There is a very engrossing talk by Professor Brian Cox about the LHC. It compresses in 20 minutes a presentation of the best scientific explanation of "what the universe is", and why the LHC is such an important project. I am sure you will enjoy this talk:
http://www.ted.com/index.php/talks/view/id/253
-------------------------------------------------------------
If you need a primer of what is a "Higgs Boson" particle, here is my simplified explanation:
Back in my early school days, I was taught about how all matter is composed of atoms. In fact, the theory of atoms being the fundamental building block of matter was first written by the ancient Greeks back in 400 BC.
However, in the late 19th century, scientists discovered that the atom is not the most fundamental particle (a fundamental particle is a subatomic particle that is not composed of any other subatomic particle). Instead, they found that atoms were composed of electron particles orbiting a nucleus containing protons and a neutrons.
This is probably the level of science that most of us were taught up to in secondary school.
In the mid-20th century, scientists discovered that while electrons are fundamental particles, protons and neutrons were not. Protons and neutrons are composed of an even smaller particle called the quark.
Quarks never exist alone. They are always found in groups of other quarks. A composite particle made of several quarks is known as a "Hadron", which is what the LHC (Large Hadron Collider) is named for.
Thus, the scientists now have 2 fundamental particles: the quark, and the electron.
Unlike the quarks which always exist in groups (you always find quarks in groups of two or three quarks), the electron is always alone (they are said to be solitary particles). However, scientists found that electrons were not the only solitary particle. Besides the electron, scientists found other solitary particles like the muon, the tau, and the neutrino. Scientists categorised these solitary particles as "leptons".
So basically, matter is made of the fundamental particles of quarks and leptons.
(There is actually another group of fundamental particles called "anti-quarks" and "anti-leptons", which are the components of "anti-matter". However, I will not discuss anti-matter in this explanation).
But how do protons and neutrons bind themselves together in the nucleus? Why do magnets attract iron nails? Why do uranium decay, (causing harmful radiation in the process)? Why does the Earth revolve around the Sun?
All these actions are actually forces that are exerted by particles on other particles. Scientists identified 4 kinds of forces, mainly:
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