sharplittleteeth

The Large Hadron Collider got turned on while we were away. And the Universe totally failed to end.

This is completely unsurprising.

Why?

Here's the deal -- the LHC is trying to find the fundamental building blocks of reality.

It does this by firing a stream of sub-atomic particles called protons around its 27km loop, using super-powerful magnets to accelerate them to nearly the speed of light,  then smashing them into other protons racing along in the opposite direction. The collisions shatter the protons into the elementary particles they're made out of.

It's a bit like ramming two Lego toy cars together - they fall apart into the bricks used to build them.

Scientists are hoping that if they smash the protons together hard enough, they'll find some elementary particles that theoretical physicists think exist, but no one has ever actually seen before.

These types of experiments aren't new. Scientists have been smashing particles together and sifting the debris for decades. What makes the Large Hadron Collider special is that it can smash things together harder and faster than any collider before it. Consequently, it stands a good chance of uncovering new particles that other colliders are just too weak to shake loose.

There's a problem, though. Those elementary particles they looking for? They're the tiniest things humanity has ever tried to detect. And most of them only exist for less than a trillionth of a second.

Given that, if you were in charge of this project, would you:

1. Turn the LHC on, and immediately start conducting experiments at maximum power, just praying that everything works
2. Spend some time running experiments with known results, using them to test and calibrate the detectors

If you answered 2), congratulations! Go get a job at CERN.

Because that's what the Large Hadron Collider teams will be doing for the next few months - running tests.

On September 10, they tested that protons can actually be fired all the way around the loop.

In October, they'll run the first test collisions to check that the detectors are actually detecting.

Then -- after shutting down over the New Year -- in March 2009 they'll run the first experiments at maximum collision energy.

Even that won't destroy the world.

Because the physicists there aren't stupid. They've run the calculations. They've worked out the risks.

As CERN point out on their website, this may be the highest-energy collider ever built by humanity, but cosmic rays collide with greater energy than the LHC can muster all the time. "Over the past billions of years, Nature has already generated on Earth as many collisions as about a million LHC experiments – and the planet still exists."


DISCLAIMER: I am not a physicist. This entry is based on reading New Scientist and the CERN website. Repeat: I am not a physicist. But the Large Hadron Collider is the biggest machine in the world. It may uncover the true nature of reality. Come on. Aren't you just a little bit excited?