LHC PROJECT SIMULATOR

More than 1200 of these segments make up the 27km-long LHC

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Slide 1 - Back to the Big Bang!
The Large Hadron Collider, or LHC, is part of the biggest physics experiment in history.

Its purpose is to find out what the universe and everything in it, including us, is ultimately made of.

This presentation tells the story of this amazing quest for knowledge. And it's a story that starts at the very beginning of time…

Slide 2 - The Universe
Here's a photo of a tiny bit of the night sky. It covers an area about a fiftieth the size of the moon in the sky.

The smudges and dots aren't stars, they are whole galaxies. Each one is made of hundreds of billions of stars. There are about ten thousand of them here. This isn't a special part of the sky, you can point a powerful telescope in any direction you like and this is what you will see.

We're standing on a planet going round a fairly ordinary star, the Sun, which is part of a common sort of galaxy made of a few hundred billion stars.

Slide 3 - The B of the Bang
Most scientists believe the universe popped into existence around fourteen thousand million years ago. Asking “What was there before?” doesn’t really make sense, because there was no time for there to be a “before” in.

It sounds crazy, but there’s lots of evidence to support the idea. This idea is known as the Big Bang.

Slide 4 - The B of the Bang
The raw ingredients of the universe we see today must have all been there, but squeezed together way too tightly for anything like atoms or even light to exist.

If we could hop aboard a time machine and go back to study what was happening in the first fraction of a second after the Big Bang, we could see how well our ideas about what makes the universe the way it is hold up. And maybe get one or two surprises.

The next best thing to actually being there is to try to reconstruct the conditions just after the Big Bang and see what we find.

Slide 5 - What Would We Find There?
It sounds like science fiction, but that's exactly the plan: to recreate the beginning of everything.

Slide 6 - The Large Hadron Collider

Slide 7 - What is CERN?
CERN is a huge international laboratory. For over 50 years, scientists from around the world have been coming to CERN to study the building blocks of matter and the forces that hold them together.

CERN provides them with the tools they need to do this. These are accelerators, which accelerate particles to almost the speed of light, and detectors to make the particles visible. The LHC is the largest and most powerful in a series of particle accelerators, each more powerful than the one before. Over the last five decades each new accelerator has been enabling scientists to probe deeper and deeper into the structure of the atom.

Slide 8 - What is The Large Hadron Collider?
Hadrons are the group of particles that includes the protons and neutrons in the nucleus of an atom. For a while scientists thought these were "fundamental particles" that weren't made of anything smaller, just like earlier scientists thought the atom couldn't be split into smaller parts.

Experiments with atom-smashing particle accelerators at places like CERN have revealed that hadrons are made of even smaller things called quarks. Don't worry if you haven't heard of quarks - you don't come across them in school science unless you study Physics beyond 16.

Could it be that we're finally down to the ultimate building blocks of everything? It turns out that if you crash hadrons together hard enough, you get loads of other particles. These don't come from inside quarks. The collisions have so much energy that some of the energy actually creates particles that weren't there before.

The LHC will collide hadrons harder than ever before, which physicists are expecting will reveal particles we've never seen before. Studying these particles, and the particles they decay into, is an exciting branch of physics called particle physics.

Slide 9 - How Does It Work?
If you have an old-style non-flat-screen TV or PC monitor, that's a mini particle accelerator.

The idea is simple: use an electric field to accelerate charged particles like protons or lead nuclei, steer them with powerful magnets, then whack them together and see what happens.

Giving the hadrons this much energy without letting them fly off out the side of the circular LHC tunnel has taken 25 years and billions of pounds to achieve.

So, what are the big mysteries the LHC experiments might help us crack?

Slide 10 - What's It For?
For a start, 96% of the universe seems to be missing. Lots of careful measurements of the way galaxies move have led scientist to think only 4% of the universe is made of normal matter we can see and touch, and energy we can detect like heat and light. The rest of it seems to be made of something completely different that we can't perceive directly, so it's called dark matter and dark energy.

The trouble is nobody knows what this mysterious matter actually is, so scientists are pretty keen to find out. The LHC just might make us some particles of dark matter so we can take a look. Or if it doesn't, maybe that means we've got it all wrong and maybe gravity works differently than we thought.

What causes gravity isn't fully understood either. Are there particles that make gravity happen? We've made up a name for them - gravitons - as we suspect they might exist, but again no one has actually detected them.

And then there's mass itself. Why do different particles have different masses? In fact why does anything have mass in the first place? In other words, what gives stuff stuff? Sometimes the very simplest questions are the toughest. Might the LHC experiments show us a particle that gives things mass? Lots of scientists are betting on it, and they call it the Higgs particle after the scientist who first predicted that it should exist.

And there are other possible discoveries. The real point is you can dream up all the theories you like about what the universe is made of, but sooner or later you have to take the plunge and do experiments to see if your ideas hold up. Sometimes finding out we were completely wrong turns out to be the most exciting result.

Slide 11 - How Can You See What's Happened?
There are four main detectors around the LHC tunnel. They're really big, complex pieces of kit. This is a simulation of the pattern a Higgs particle might make in one of them.

The trouble is, with hundreds of millions of collisions every second, picking out the interesting ones is like trying to find a particular grain of sand on a beach. And the experiments will run for at least ten years.

Slide 12 - That's a LOT of Data…
You know what a scientist at CERN did last time they needed to share lots of information between scientists around the world? He invented the World Wide Web (www.) that we all use today!

Now, because of the vast amount of data that the LHC is going to produce, the scientists at CERN are using the Grid. The Grid networks computers around the world in order to share processing power as well as information.

It's the ultimate supercomputer, and they're going to need it to find that grain of sand as the total amount of data that the LHC will produce will be about equal to writing down every word spoken by everybody in the world, ever!

Slide 13 - Watch This Space!
The most exciting part of this experiment is that nobody knows for certain what will happen. If they did, the whole thing would be a huge waste of time and money. The only thing everyone is pretty sure about is that the experiments will reveal something, and that it will change our understanding of how the universe works. And the people in this control room at CERN will be at the centre of it!