V/O: November 26, 2007 promises to be an extraordinary day*.
V/O: The most advanced scientific instrument ever built will be switched on. The scientists behind this experiment are hoping to unlock our Universe's deepest secrets.
V/O: Their method: nothing less than recreating the moment that exploded everything into existence... the Big Bang.
BRIAN COX: Particle physics is a strange job. I mean, you do sometimes wake up and think, you know, I go to work every morning and my job is to recreate the conditions that were present less than a billionth of a second after the Big Bang.
V/O: The hope is that in recreating the moments following the Big Bang, we will get a glimpse of the fundamental particles that make up our entire Universe.
ALVARO DE RUJULA: Well, the very big questions that humanity has posed always are: where we come from, what are we made of, what is the future of the Universe? But the Universe, like everybody else, is made of little pieces, which need to be understood in order to understand how the Universe works.
V/O: There are 2000 scientists that inhabit a labyrinth of tunnels deep under the suburbs of Geneva.
V/O: Here lies the European Organisation for Nuclear Research where they are putting the finishing touches to the Large Hadron Collider or LHC.
V/O: When the LHC is up and running, sub-atomic particles called protons will be accelerated within this tunnel until they are almost at the speed of light.
JIM VERDI: So there's a beam of protons which comes at about this level one way and there's a counter rotating beam of protons coming the other way and they collide head on.
V/O: Every second there will be 800 million collisions. Just a tiny fraction will be of interest.
V/O: As the protons fragment, a magnetic field separates out the different types of matter.
V/O: Among these may be found our Universe's fundamental particles.
V/O: Twelve types of matter particle have already been observed in colliders across the globe.
V/O: Leon Lederman was among the first to set eyes on two of these.
LEON LEDERMAN: We have the outrageous ambition to understand the world, how it works. That's our objective.
V/O: To explain how these various particles interact to make the Universe tick, Lederman and his peers use something called the Standard Model.
V/O: But in piecing the Standard Model together, they have noticed that things don't quite add up.
LEON LEDERMAN: There's something spooky about the Standard Model. It doesn't really work. So we know that there is something sick in our theory.
V/O: The thing that is yet to be discovered in the Standard Model is that thing that gives the fundamental particles substance, that turns them into matter we can touch. It is called mass.
BRIAN COX: There's a big hole in our knowledge appeared, and the hole is related to what mass is.
V/O: In order to connect the Standard Model to the world we see around us, scientists had to think of a way for particles to gain mass.
BRIAN COX: The best theory we have at the moment for the origin of mass, or what makes stuff stuff, is called the Higgs mechanism. And the Higgs mechanism works by filling the Universe with a thing, it's almost like treacle. And by the Universe, I don't just mean the void between the stars and the planets, I mean the room in front of you. And some particles move through the Higgs field and - and talk to the Higgs field and slow down - and they're the heavy particles. So all the particles that make up your body are heavy because they're talking to the Higgs field.
V/O: The Higgs field is the missing link in the Standard Model. It can explain how we can have a world of solid objects from particles that appear to have no mass.
LEON LEDERMAN: The Higgs brings simplicity and beauty to a nature that looks too complicated. It makes nature simpler than we think it is. It introduces a kind of symmetry, a kind of beauty that gives us an understanding of one of the most puzzling features of the Standard Model.
V/O: To prove the existence of the Higgs field scientists have to find the particle linked with it. Yet in the forty years since it was first thought of, no one has.
V/O: Now the hopes of ever seeing it lie with the Large Hadron Collider.
LEON LEDERMAN: This is like a huge new microscope that will bring us visibility to a different world. It would be a tremendous discovery.
V/O: The LHC will generate energies seven times greater than any other collider. By doing so it will take us closer to the beginning of time than we have ever been before.
V/O: And somewhere in those first few moments the Higgs particle was created.
ALVARO DE RUJULA: Will we find the Higgs particle at the LHC? That, of course, is the question. And the answer is, science is what we do when we don't know what we're doing. And one reason to look for this thing is to see whether we find it or not. So I don't know whether we will find it or not.
V/O: If they don't find the Higgs, it could also mean that this elusive particle simply doesn't exist.
V/O: Yet rather than close the door to our understanding of the Universe, this prospect could actually enhance it.
ALVARO DE RUJULA: It can be argued that the most interesting discovery would be that we cannot find the Higgs, proving, practically, that it isn't there. That would mean that we really haven't understood something. That's a very good scene for science. Revolution sometimes comes from the fact that you hit a wall and you realise that you truly haven't understood anything.
BRIAN COX: I think we are on the verge of a revolution in our understanding of the Universe. And now I'm sure people have said that before, but the LHC is certainly, by far, the biggest jump into the unknown.
[*Please note, the LHC launch date has now changed since this Horizon programme was made.]