CERN tour notes Part II: The door leading to the Big Bang

LHCb is one of the four experiments at CERN, which specializes in detecting antimatter created after the proton collisions in the LHC accelerator. Record a tour of the depths of the earth. Second article in the series.

This is the door leading to the Big Bang - this is how Prof. Richard Jacobson, a researcher in the LHCb experiment, defined a yellow iron door, 100 meters below the surface of the ground in a rural area in France, under the Jura Mountains, on the tops of which you can still see remnants of snow at this time of the year (April 29 2014).

The tour, attended by Israeli journalists who came to CERN in a delegation organized by the National Academy of Sciences and Arts, following Israel's accession as a full member of CERN.

LHC is designed to answer two basic questions - one of which is the most basic components of matter, and the second question is to understand how they communicate with each other, what is the glue that holds the entire universe together. The familiar structure of particles and forces was not always in the current state. When we 'go' back in time, we reach a time when everything was more compressed and the forces were different. We at Seren not only want to examine the universe, we do that with telescopes, but we try to recreate the preconditions.
As we know, even with telescopes we can look back in time. When we look at the sun, we see it eight minutes late. The next star is four light years away, to view the nearest galaxy we need to look 2 million years into the past. But there is a problem, when you look through a telescope, it can be assumed that you can look back to the big bang that the ink is still chasing us today. However, there is a small problem. In the period that occurred about 380 thousand years after the big bang there is a kind of wall. Up to that point, there is no problem 'moving backwards in time', because the universe is transparent, but before it was 380 years old the universe was actually opaque. If you look at that period you just see a blurry patch of material. The temperature of the universe at that time was about 3,000 degrees. We are all familiar with this elliptical image known as the "Mona Lisa of the Universe". We call this the "cosmic background radiation" and we see it all the time in the newspapers. This is a photograph of the moment the light began to move freely. Radiation surrounds us and is everywhere. Therefore we cannot observe through a telescope. All we can say is that these are the properties of the universe today, and that the foundations for these properties must have been laid at a much earlier stage.

Therefore there is no choice but to take the step of restoring the conditions that prevailed in the early universe. We know the pressure and temperature were high. To emulate these conditions I am required to use an accelerator. I accelerate two particle beams, slam them together, and I get exactly the same conditions that particles collided with in the early universe. The higher the energy of the collision, the higher the temperature and we can mimic events that occurred earlier in time. We examine what types of particles are created as a result of these collisions and what types of forces controlled their behavior. The LHC can be defined as a time machine.

The energy of the LHC is such that during collisions we get heat measurements equivalent to a billion times the temperature at the center of the Sun. In the center of the sun there is a temperature of 10 million degrees. This is a typical temperature and there are many stars that is the degree of heat in their center. There are even stars whose temperature in the center reaches 100 million degrees. In the early universe, heat dimensions a billion times stronger than this prevailed, and we reproduce them at the LHC. Remember, at the time when the universe can already be seen, at the age of 380 thousand years, it has already cooled to a temperature of 3,000 degrees. The amount of heat I'm talking about prevailed one hundredth of a billionth of a second after the big bang, meaning if you take a second and divide it into a hundred billion little units, the moment we're investigating is the first unit of it. It's very close to the Big Bang, but the Big Bang was an era where things happened very, very fast. Something happened every fraction of a billionth of a second. The goal of the LHC is to return to that moment that if you blink you miss it."

"The interesting thing is that we have theories that not only explain what happened but also predict what should have happened next. We have a very good understanding of how the universe behaved at those moments and from that moment on, for example a microsecond after the big bang, the process in which the protons and neutrons were created took place. Three minutes after the big bang the first nucleus was already formed, the first atom was formed 380 thousand years after the big bang, the first stars were formed half a billion to a billion years after the big bang, the galaxies were formed shortly after, but to know the origin of all this we have to go back To recreate the time when the foundations were laid for things that were created hundreds of millions of years and billions of years later."

"One of these things is mass. In the sixties, some people predicted the existence of a mechanism by which nature gives objects a type of mass that stops them from moving at the speed of light, a basic force in the universe that made possible the creation of complex objects such as the human body, planets and stars. They predicted this decades ago and two years ago we predicted the particle that makes this possible, and it has exactly the predicted properties."

In search of antimatter

"Now that we have this information, we are looking for answers to other important questions, one of which is the dark matter, and we will now look for particles that will shed light on the dark matter.
The role of the LHCb is to study so-called antimatter. When we look at the universe today, we see no antimatter at all. However, this does not mean that antimatter is the work of science fiction. It can be produced, studied, seen how it behaves, but it does not exist in nature. There is no star, or planet composed of antimatter. He had to disappear. However, when I apply energy in an accelerator, I always produce the same amount of matter and antimatter, but I see that in their development they behave differently. To some extent, nature treats antimatter differently than matter in a small number of cases and we don't fully know why. The small differences in the properties of matter and antimatter cannot explain why all the antimatter in the universe disappeared in the first fraction of a second of the universe, leaving only matter.

In response to the question of the science website, is the antimatter hidden in the 95% (the components of the universe that are not normal matter - i.e. dark matter and dark energy AB), Jacobson said: "This is one of the possibilities, and we can say that we may be in a rare universe where matter flies In one direction and the antimatter flies in the other direction but after 14 billion years you would expect to see some sign of a mixture between matter and antimatter and of course you would expect to see their collisions which cause the ionization of the two particles and the form of radiation that we would sense in our devices.

Photo: Avi Blizovsky

In the same topic on the science website:

• Cern CEO Rolf Hoyer: My dream is to find the first particle of dark matter. First article following a tour of the Cern facilities
• LHCb confirmed the existence of an exotic hadron
• The bright future of the dark universe
• The CEO of CERN at the ceremony of joining Israel to the organization: Israel and CERN have a rich past of cooperation

"There were events that were suspected to be the ionization of matter and antimatter, but a quick check of the spectrum coming from these events proved that it was not an ionization between matter and antimatter. The LHCb has a neat program to try to better characterize the small differences between matter and antimatter. Our detector makes it possible to absorb matter and antimatter and study the evolution of both. During a pico second or so we look for a way to locate the differences in behavior. We examine all types of matter and antimatter, but the most interesting ones are the beauty quark and the beauty antiquark, and also the magic quark and the magic antiquark. Of course we are interested in all of them, but these are the heaviest quarks and antiquarks and we are sure that they existed a hundred billionth of a second after the big bang." Jacobson concludes.

After this introduction, we went down to the yellow door, at a depth of 107 meters underground, to see the facility, and you can get an impression of it mainly in the photo gallery attached to this article.