What's a collider?
When people talk about the Great Hadron Collider, the first thing that comes to their mind is that it's the biggest experiment in human history, because it's a 27-kilometre ring in the foot of the Swiss Alps. The picture below is what it would look like on the surface, but it's actually a ring that's dropped in a tunnel between 50 and 150 metres underground.
The device accelerates the protons and the cores of lead to speeds only a few metres per second less than the speed of light. Having this speed, the proton passes these 27 km 10,000 times per second. Then it hits them, the particles inside the device rotate both clockwise and counterclockwise. At four points, these beams intersect and impact, a huge temperature is reached and we study how the universe behaved in the first minutes of the Big Bang.
Another interesting fact about the BAC is that it has the highest temperature in human history, which is about 40,000 billion degrees Celsius, and that's the temperature that happens at the moment of the collision of particles with enormous energy, and if you look at how the universe evolved, it's going to match the first microseconds after the Big Bang.
At the same time, the collider has the lowest temperature in the universe. For example, Antarctica has a temperature of -95 °C, in outer space -270 °C. And the liquid helium temperature inside the Hadron Collider is 273.3 °C. It's needed for magnets that make up a 27-kilometre-long ring to be superconductive.
How much energy does the collider use?
CERN consumes as much energy as the entire canton of Geneva, with approximately 50,000 inhabitants living there, and around 15,000 engineers and scientists from all over the world worked on the Great Hadron Collider.
It's the most expensive human terrestrial experiment, and it's overrun only by ISS, which is a few times more expensive, but the cost of this project is because it's very expensive to get into space. If you compare it to normal things, you could build 20 Samara Aren or 6 Gazprom Aren for the cost of a collider.
If such examples are also difficult to understand, then here's another example: If the value of the Hadron Collider is divided by the Rollon price for 2016, 13 towers can be built from this number of packages that reach the Moon.
Why would you do that?
To explain the importance of the Hadron Collider, let's first look at what we're made of as matter and what surrounds us. It's all made up of atoms, supertight matter inside the atom and electrons. In the picture that we're used to studying these structures at school, there's a big mistake. It's on the scale, imagine that the atomic core is the size of a fingernail. Then the electron has to rotate from it at a distance of 100 km. So we're all empty space.
But why isn't the atom falling apart, why isn't everything that we're made of? It's all about electromagnetic interactions: if there's two identical charges, they push back, if there's two different ones, they're drawn. But why? From the point of view of modern physics, these attractions and push-ups are caused by the exchange of other particles. So we don't break up because the electronic shell and atoms that interact with other atoms and exchange photons, they're connected.
The atom consists of electrons and nuclei that exchange photons, so they're connected together. And the core is made of neutrons and protons. And why isn't the core falling apart? Because the protons are positively charged and pushed away, and the neutrons are not charged. So they also have some kind of interaction within the core, which is called strong. Strong interaction is the exchange of gluons.
It's the kind of stuff that we're made of. Protons and neutrons are made of two types of quarks. They're connected by helions -- blue letters. They've formed protons and neutrons, and then they've got to put electrons on them, they're chained with photons. And there's neutrino particles, even through my arm's finger -- billions of particles per second, and they're being caught by huge particle detectors. For example, one of them's in Japan -- it's a huge mine filled with water, where neutrino can be caught piece by piece.
There are other types of particles that don't surround us because they're unstable, short-lived, and heavier, they don't break down into lighter particles.
How does energy work?
To understand BAC's work, you also have to know how energy works. The school program explains that the body has energy when it can do work. I would say that the body has energy when it can do something. For example, if I drop an object, then when it falls, it can fall -- it's work, it's broken electromagnetic connections, it has potential energy when I plant it. It's also important that there's a law of energy conservation -- if I plant an object, then I give it kinetic energy, as much as it goes into potential energy, and then it goes back.
Warm energy is also kinetic energy. If you lose your hand, it becomes warmer, that is, kinetic energy is transferred to heat, the molecule starts to move faster, and so kinetic energy goes back to the kinetic energy of my hand molecules.
But then Einstein came in and, using his famous formula, he said that mass is energy, and it opened up huge possibilities, and it turns out that kinetic energy can be pumped into mass energy and back, and if we push the particles to huge energy and hit them, then the stored kinetic energy can turn into the birth of new particles, and that's how the Hadron Collider works.
That's why boosters are needed: they're pushing proton particles to kinetic energy, which is 10,000 times higher than its mass energy, and at the moment of impact, they're producing new particles that don't surround us, so from a physicist perspective, BAC is needed to create new particles, for example, that's how the Higgs Boson was discovered.
What's Collider doing?
In order to disperse the particles, radio frequency resonators are used. A 27-kilometre booster has resonators in two places, constantly changing the electrical field, the particle is flying, it gets a kick, it flies another 27 km, then it gets a kick and so on again. It flies almost at the speed of light, so it happens 10,000 times a second. Even as it moves for a few minutes, it already gets a huge amount of energy.
We need magnets that hold particles in the circle. The size of the collider depends on the magnets. If we could make a more powerful magnet, the device would be smaller. But there's another reason why we need magnets. Because the beam is made up of protons that are pushed away from each other, and they need to be focused in order to have as many collisions as possible.
That's how the BAC works -- it runs hundreds of known particles to get one new one. It lives in a very small period of time, falls into particles that fly in different directions at the speed of light. But how do you record a new particle if it doesn't live so much?
How do we record the discovery?
This role uses a huge particle detector, it removes every impact of protons and lead kernels. On the BAC of these detectors four. One of them, ALICE, weighs 10,000 tons like the Eiffel Tower. The most heavy detector is CMS, its mass is about 18,000 tons, and it's the one that discovered the Higgs Boson.
This is the image of a proton collision on the Great Hadron Collider. Each line here is a trace of a birthed particle. This is a real photograph, on the left, you can see that it was taken on July 4, 2016 at 4:18 p.m., 25 seconds.
How to make a discovery?
To be simple, let's say there's a new particle that breaks down on the particles we know, for example, when they were looking for the Higgs Boson, scientists already assumed that it had to fall into two photons, which means that the detector has to understand not just where and what sort of trajectory the particles were, but what they were.
So the size of the detector and the structure of the detector is the so-called structure of the mattress. The first layers of detectors are pixelous, they're like pixels in the smartphone cameras, but they're not picking up photons, they're picking up particles. Let's say the charged particle flies and the pixels light up, then you can see their trajectory, and if there's no trace, then the particle was uncharged.
Then the calorimeter that destroys the particles and then leaves the "livers," you can measure the energy of the particles by their size, and you can understand the proton pulse, the calibrators can determine their energy, and then you can understand the mass of the particles.
How did the Higgs Beacon come into being?
Imagine there's a collision where only photons are born, so we can catch them, and they'll appear in different processes.
Now it's assumed that it's very rare in these same processes to have a Boston Higgs. It has a mass, it's split into two photons, and in this process it has to respect the law of impulse and energy conservation. How are these two photons different from the photons that appear in other processes? The laws of conservation -- the Boston Higgs has a certain mass and impulse, and if we count the so-called invariant mass, that is, their total pulse and energy, we can count the mass of the boson.
But there's a huge background -- a billion large photons -- to separate some photons from others, we assume that they were all born from the Higgs bosons, that we get a smooth distribution and that we look at the heterogeneity, so you can see that some pairs of photons are a little larger than others, so that's where the particle that's falling into the photons with specific characteristics is born, and that's how it looks like the opening of the Higgs boson.
What else do you need a BAC for?
There are a lot of unknown processes in the universe that we don't understand, for example, the universe exists and, according to modern theories, the amount of matter and antimatter should be the same. If five quarks were born in a collider collision, then five antique quarks were born, but if it was done after the Big Bang, we shouldn't have existed, the universe would have been empty, filled with photons.
There's another goal: to look into the past of the universe, the speed of light is limited, and when we look at the telescope, we see galaxies in the past, but the method has a limit of 400,000 years after the Big Bang, when the universe was not transparent, the only way to look at it is by boosters of elementary particles.
There are other challenges for scientists -- for example, to determine the composition of the universes that surround us -- which the BAC is also trying to answer, there's an antimatter factory where scientists drop antiatoms and watch them fall, and look at them as gravity affects them, or they push particles to try to create a piece of antimatter, but to do that, you have to upgrade BAC to make more collisions.
The construction of a 100-kilometre collider at CERN is currently under discussion, and its energy will be 10 times higher than that of today's collider. It will be called Future Circle Collider, the circular collider of the future. It will appear in the 2050s.
Why do BACs need more than physicists?
Most of these studies don't have practical applications, but everything that's done is happening for the first time, so it's data for unexpected discoveries. In the future, they can become technologies that we use -- for example, the Internet was invented at CERN 30 years ago, and they downloaded the first giff.
Because of the accelerators, for example, the first GRID system is a network of computing capabilities all over the planet, and it was needed to store a huge amount of data that the collider produces every second.
In the early '70s, CERN came up with a sensor screen, but it took another 40 years before the first iPhone came out and revolutionized the usual.
There are a lot of medical technologies that have originally been invented for accelerators. For example, PET is a method that, for example, is detected by cancer tumors. In fact, it's a particle detector where a person is placed, where they inject a small dose of radioactive material, the cancer begins to fly photons out of the cancer that show that a person has a tumor, or there's a special technique for the removal of cancer tumors, which is an adrone therapy. Where a beam removes a tumor that is difficult to get surgically. So the answer to this question about why BAC is needed depends on who you ask. With it you can learn how the universe works, a politician will say that it can be used to develop science, and an economist can make a profit.