CERN – Originaltranskript Protagonist/innen

PAULINE GAGNON

#00:03:46-2# Ok, welcome to CERN. This is in fact the control room for the ATLAS experiment. ATLAS is one of the four large experiments now going on at the LHC - the Large Hadron Collider. The Large Hadron Collider is a huge ring of 27km, and thats an accelerator where we accelerate protons in two different directions, and then they collide in four points. We are just above one of those colliding points at the ATLAS experiment. So ATLAS is both a large collaboration of about 3,000 people, I'm one of them - my name is Pauline Gagnon, I'm Canadian - I work for an American institute, Indiana University, and I live here in France and I work in Switzerland, but thats just about the kind of sociology that you have with the people here at CERN. So its a very mixed background, in ATLAS alone we have people from more than 70 different countries. There are only 38 countries participating in the experiment, but since people like me with - I'm Canadian and I grew up in an American institute - so, then there are people from different countries working together. The common language to work is broken English, so everybody speaks it with their own mistakes and all that, their own accent. So. But people get along and we usually get the work done.

#00:05:22-9# All this, you may wonder, what's the purpose of all this? Why do we go to such an extent? So much work, 3,000 people just to build the detector and work on it and analyse the data that comes out of it. Essentially, its just to increase the knowledge about what matter is made of. What is the universe where we live, what is this place we are in and where did it come from - where is it going. So, it's very fundamental questions, it's nothing that puts food on your plate right away. The food might come later on, because with research, you never know what will come out of it. We're going out and - let's see what we find! It's a bit like a mushroom hunt, you know, you can bring back something that is really good and you make a good dish and you might not come back with anything suitable.

#00:06:18-3# So, I was saying earlier that we have the accelerator which accelerates the particles and then we have the detectors that are there just to detect what comes up. A detector is just a very fancy camera, so we take a snapshot of what happens when two protons come into collision. All the energy released in the collision then is in one small tiny point and it allows you to create a particle because E = MC2, so the energy that you have put there, you can transform it into mass. the C squared is just the exchange rate between energy and mass. So we can create new particles and study how they behave.

LUCA BOTTURA

#00:09:11-8# I saw in 1995 there was an opening at CERN and LHC was due to start very soon. And so this is why I decided it could be a good opportunity and so that's why I jumped. Its actually beautiful to be part of a modern 'cathedral' - that's the way I see it. It's like being a community with a single aim and a single scope and we're producing machines that nobody has built before. Like a cathedral.

#00:09:48-2# I'm in charge of the magnets at CERN - everything that has to do with magnets for the machines and I arrived at CERN in 1995 after a few years of working in thermonuclear fusion. I think I was lured here by the the adventure of the LHC, so it was at the beginning of the LHC. In fact where we are today is the hall where we do all the maintenance, the work, the construction and the reconstruction of the LHC magnets. We do mostly dipoles here, and we work with quadrupoles as well - these are the main elements that make up the superconducting cryostat of the LHC.

#00:10:22-2# Well magnets are the main mass in an accelerator. As you've seen in accelerators at CERN, magnets guide particles - they drive them around on a circular path so that they can go back to the real accelerating component which is a cavity. But they need to do that thousands and tens of thousands of times a second, like in the LHC. So the main function of the magnet is to guide the particles back - this is what we call dipoles - and they have to focus them onto the closed orbit of the machine  - and these are the quadrapoles. In addition to that , the quadrapoles also squeeze the beam down to a small size - smaller than a hair - in the experimental region. This is the main function of the magnets.

#00:11:06-3# To give you an idea of power and strength... let's start with electrical power that we use because we need electrical power to run the machines. So CERN uses roughly 160 megawatts of electrical power only to run the accelerators and that's more or less the consumption of a small city like Geneva. So it requires indeed a lot of power in spite of the fact that we use superconductors. So the LHC itself uses about 60 megawatts and the whole complex before the pre-injectors uses also about 60 megawatts to inject the beam into the LHC. As to the magnetic field: to give you a feeling for how strong the magnetic field is you should imagine a magnetic field in our magnets of 8 tesla produces forces. These magnets are 15 meters long, and the forces produced on the magnet are in the order of 350 tonnes  per half magnet. So 350 tonnes per meter of magnet for every half of the magnet. So it's a lot of weight that needs to be held by the very strong structures that we put around them. This is why the magnets are all encircled in these very strong structural steel that keeps them together. As to the magnetic field itself - the nominal field is 8 tesla - you can compare that to the magnetic field of the earth which you can barely see with a magnetic needle. so here in Geneva the earth is producing about half a Gauss and if I compare that to the magnetic field of the LHC which is 8 Tesla - that's a factor of 100,000 more. So the LHC produces 100,000 more magnetic field than that of the earth.

BENIAMINO DI GIROLAMO

#00:15:47-4# We are 90 meters underground, between the Jura and the Lake of Geneva, and this is the cavern of the ATLAS experiment. Its the biggest experiment in high energy physics we ever built, so it's - the cavern is huge it's 60m by 30m. Inside there is a detector, it is 7,000 tons - it's the same weight as the Tour d'Eiffel in Paris. And, the cavern is fully occupied, in fact by our detector and this is one of the detectors that has measured the Higgs-Boson, this year and last year. And now we are in maintenance mode so, this is the period in which we stop, we open the detector and we work on it.

#00:16:42-9# So the aim of all this is quite varied - one of the main aims, one which you can also find in the press is the discovery of the Higgs-Boson. Apart from being a particle it's a mechanism - it's a field -  and it's the mechanism which gives the mass to all the other particles. But this is only one of the aims of this detector - this is a general purpose detector and can measure several aspects of nature. Several aspects of nature in very tiny dimensions. And this backwards in time - the accelerator itself is a time machine. Raising the energy allows us to go back in time and to reach a point a tiny amount of time after the big bang.

#00:17:39-0# The description of nature as we know today is at the moment, I would say, quite complete - especially after the discovery of the Higgs-Bosons. But there are many, many things we don't understand that ... for which this detector has been built for and these for example are questions about matter and well, there is one very basic question: that is the difference between the amount of matter and anti-matter. Because all this... knowledge, all this building of knowledge and building of theories tells you that ... the big bang bang and at a certain moment in time was..... beginning. And all the matter, all the matter that exists in the universe now comes from a very small point from where everything expanded, in a way. But to have this final tiny point with this enormous amount of energy and matter - density- you must have a way to put all together.... and, the only considerable way you can see about this is symmetric ... a symmetric way of thinking. That you must have the same amount of matter and anti-matter. And then of course you can ask yourself: so why is it not myself in anti-matter that is destroying me. So in a way there is a tiny difference between the matter and anti-matter that makes all this exist. And this is certainly a mystery, there are other mysteries like the amount of dark matter, we see that if we look ... we can look at this kind of phenomena also in space and we can look at matter in space and we can not really compute totally the matter that is in space, we can compute it but we see there is a deficit and and that is what we call the dark matter and the dark energy - that they are not exactly the same thing to make this size of universe and this way the matter is distributed possible. And this is certainly a mystery.

#00:20:07-0# Another mystery I would like to give you is that I explained to you that energy and time are correlated and the product of energy and time has to give you a constant. Now, if you think for a moment that the time you're aiming at is 'zero', then to keep this as a constant the energy has to be infinite. So there is in itself a paradox here and something that maybe we can't approach - we can do our best - but the time 'zero' is something which is difficult.

TATSUO KAWAMOTO

#00:23:00-7# What we do in research sounds a bit strange, on the one hand we want to test and confirm our present theory and at the same time we are always looking for things which destroy our present theories to find something new.

#00:23:49-0# You ............. want me to explain the Higgs particle? Yeah.... this is.... yes.... mmmh. I have been wondering how one can correctly and easily explain the role of the Higgs field, Higgs mechanism and the Higgs particle. This is something which is difficult for me to do. How can I explain? Higgs-Bosson has such a unique and important role - even one that allows us to exist - this important particle hadn't been discovered till just one year ago. So, in a way, this is a very frustrating situation. We know the theory works very well, however one of the key elements of the theory hasn't been confirmed by experiment - nobody has seen whether this exists or not. Now it's very likely this will be discovered. So in a sense, the last piece of our theory has been found and put into the jigsaw puzzle, but in a jigsaw puzzle this would be the completion, then you glue it and put it on the wall or take it apart. But in physics it doesn't work like this. Up to this point the analogy of the jigsaw puzzle works but after that it doesn't hold anymore. What we want to do is -  first of all, we have to confirm if this particle is really the last piece of the jigsaw puzzle, not something similar but it maybe something totally different.

YVES SCHUTZ

#00:28:13-4# We have a picture, a cosmological history of our universe, nobody tells us that is the truth. but within our present knowledge this is the best we can do and indeed it does explain very nicely everything we are able to observe. Remember, what we are studying at the LHC is matter, so matter, well visible matter,  constitutes only 4% of the universe. All the rest is unknown, dark matter - we know exists but we don't know what it is. And something even more mysterious is dark energy - again we suspect it exists cause we need it to explain given properties of the evolution of the universe but again we don't have any idea what it is. So today we are in a situation where we understand 4% of the universe and we ignore what the rest of it is.

#00:29:39-4# #  So the specific place where we are now - this is ALICE experiment we are looking to recreate primordial matter. Matter as it existed shortly after the big bang. Here we are talking fractions of a micro-second after the beginning of the universe. At that time temperatures were extremely high, energy density was very high and matter was in a completely different shape than today. So we recreate this  primordial matter, try to understand nature and properties of this matter and then how it evolved from its state in the early universe to the state as we know it today.

#00:30:31-7#Imagine in a single collision we are producing, about 10,000 particles, running through the equipment that must be identified. So we don't see the particle itself, we take a picture of the track a particle leaves as it passes through the detector. Like if you look at a ski slope - you don't see the skier but the you can identify weight, size and direction by the traces he leaves behind. And for a full trace of the skier you need a big field!

#00:31:30-9# We use brute force, we aren't very smart. We use the energy from a collision to create these new particles. We need to bring a small particle up to a very high speed, close to the speed of light, so for this we just need big machines! Using magnets to make the particle turn and electricity to accelerate it - and a million other things to make the whole thing work!

#00:32:14-3# And I think CERN is a really good example for humanity following a common objective. Even if we don't discover anything in science - I think having achieved that is a major achievement.

CLAUDIA WULZ

#00:35:09-7# In the beginning I was heavily involved in building a system that we call 'the trigger system'. This trigger system actually selects online , in real time, the interesting collisions to be recorded and analysed later. This involved the development of an electronic system which operates very fast. It looks at a collision 40 million times per second, like a digital camera, which takes 40 million pictures per second. It not only takes the pictures but it looks for interesting patterns for example. And if there are, which is only the case a few hundred times per second, then the trigger system recognizes these and marks them for recording. Like if you take lots of snapshots with a camera but you eliminate those that you do not like. But we do that online extremely fast.

#00:36:34-9# Our first important discovery was a particle that looks very much like the so-called Higgs particle which is also called God particle but this is a term which physicists don't really like.We have discovered a very new particle and now we are going to measure all its properties and make sure it is really the long sought Higgs particle or if it is indeed something completely new. But actually this experiment was built for another main purpose which was to discover if there are new forces in physics. We all know gravity, for example, but there are also other forces such as electro-magnetic forces in the universe. But maybe there are other forces we do not know about and this could be discovered here. We could also discover completely new spatial dimensions which might be very small meaning till now we haven't been able to see them, but with a tool like the Large Hadron Collider and this experiment we can use them like a giant microscope and look deep into nature and we hope to find something very new.

#00:37:57-6# For example it is imaginable that gravity becomes a very, very strong force. Much stronger than we are used to it when we go to very small distances. For example: when you smash 2 protons against each other as it is done in the LHC then you really come to very, very small distances. And it is possible that gravity becomes very strong. So if gravity becomes strong then we can also create mini black holes. Microscopic black holes. So this would be a spectacular new signature for up to now unknown physics.

#00:38:38-0# It's a constant struggle and of course sometimes the kids complain, 'Mummy there's nothing to eat!' but I'm not alone and one has to get all the help one can. I think even if the family suffers, in the end they see how enthusiastic we are and they see that we've achieved something really satisfying - normally families understand. But I should also say there have been lots of divorces at CERN, mainly because of just too much work. People are enthusiastic though - these are not people that come at 9 and leave at 5 and look at their watch, they really like to spend the time here and put in all the means possible to get results and also to get personal satisfaction.

MASSIMO LAMANNA

#00:39:45-4# This centre is at CERN and has essentially two main and very important connections. One connection brings us to the experiment, so essentially the main flux of data is from the experiments to here. So when beams collide, the results of the collision are recorded, filtered through different levels of filtering and eventually they are shipped here via a dedicated network. So this is the first connection. Data arrives here and is stored and ready to be immediately analysed. This is just the first part of the analysis, we call it 'general reconstruction'. The idea here is that from the raw data which we receive from the experiments we reconstruct, for example, trajectories, from which you can identify particles and assign them energies and directions.

#00:40:59-9# This data is also shipped outside. They are shipped directly from CERN to important computer centres, more or less comparable to this one which in turn redistribute data to other places like universities or university type facilities where the final analysis will be done or other activities connected with analysis of the data. I think one can visualize data coming from the experiment, being stored, used for initial reconstruction and also distributed. So this is the backbone of our activity.

#00:41:47-1# I was born in 1964, and, talking with people of my age, came to the conclusion that the Apollo period end of the 60's beginning of the 70's had a big influence on us. Initially it was a big fascination with astronomy and astronauts which eventually, getting older, became an interest in physics and so on. I think there's a specific correlation between astronomy, physics and that period of space exploration. On one side there's astronomy with gigantic distances, worlds you can not really visit directly, and there's particle physics which is a kind of mirror image - you go smaller and smaller. So you find worlds which are really fascinating, strange sometimes, bizarre but it's clearly one of the things which moved me to go into physics. And now, even if I'm more in computing, there's a pride in saying these experiments are something really interesting, really cool, and we are making our small contribution.

I think for somebody with a physics background that CERN, even if they move on, keeps this fascination. It's our home. It's our dream place. I think it is so.

SIGURD LETTOW

#00:45:55-8# We have our own fire brigade. We have our own emergency services. Actually we are like a city, and this is the challenge also in my job, because you asked me in the beginning where we are here. I have to, we have to manage a small city, and to give you an idea of what I mean by city - we have roughly 10,800 guest scientists coming from all over the world, 120 nationalities, we have roughly 2,500 staff, we have 500 postdocs , 500 students and apprentices. So it's a population and needs accommodation and services as any customer would need in a small city.

#00:46:52-5# In some sense we are both an organisation like any other, but we also provide our own legislation, if you like. Because the convention gives us the right and also the obligation to handle certain things ourselves. For example if we fix our salaries we cannot simply do it, we have to do it according to the rules approved by our 20 member states. In some sense we're a kind of state in the states. What we need is a long breath. This is sometimes a problem if you discuss things with politicians. They're used to working in horizons of 3 - 5 years. They expect a return on investment which is more or less immediate. Immediate means tomorrow. But we have seen by the example of the world wide web which was invented here at CERN , you need on average at least 10 - 15 years between the first basic ideas and the first industrial product.

CHRISTOPHE GROJEAN

#00:49:05-9#   So, I'm a theoretical physicist. My job is to come up with some ideas, some possible explanations, then I try to understand what are the consequences of these ideas and how you can test these ideas using experimental result. In particular, experimental results being obtained now in this LHC , this big machine that has been built here at CERN which is working pretty well at the moment.

#00:49:43-0# Good ideas can come at any moment and you have to be ready. It can be dangerous too! If you have an idea while your driving your car you have to keep your ideas. When you getting back home to take a little piece of paper to writing down your ideas and try to finish your computation.

#00:50:12-7# Most of the time you make mistakes but from time to time you are right - and you understand something new. That's fantastic - it's a good feeling when you come home in the evening because you know more than in the morning.The feeling of having thought of something nobody has done before is what's really exciting about research. For a few moments you are the only person on earth who has a clear understanding of a problem.

#00:51:00-7# Discovering the Higgs-Boson is not like discovering yet another particle. What we are really after is trying to understand some fundamental laws, some fundamental principles that govern the universe. So for a very long time one main theme of particle physics and theoretical physics was the Gauge principle. So the Gauge principle is really the process that explains how particles interact with each other - with the exchange of the Gauge-Boson. And maybe with the discovery of the Higgs-Boson we are about to discover a new fundamental principle of nature that could really govern how the universe is structured.

#00:51:45-0# But again - we are not so much interested in new particles. What we really want to understand is 'what is the principle behind these new particles?' Is the discovery of the new particle telling me something more fundamental things about nature - is there a new space-time dimension, is there a new interaction... a fundamental interaction between those particles. That's really what we are about. I mean, the fact that till now we understand interaction as the exchange of (incomprehensible) - that was a really big step forward in the understanding of nature. But still there are a few things that we don't quite understand. For instance the fact that electro-magnetism is described by one particular symmetry of nature, there is a weak interaction which is described by another symmetry, there is a strong interaction - yet another symmetry. Why those particular symmetries? Is there something deeper behind those symmetries - a bigger symmetry for instance? That will unify all those symmetries associated to the different interactions. And, yeah, we are trying to understand these kinds of things. We have good ideas but we still don't know if our ideas are true or not.

JUAN CARLOS PEREZ

#00:54:57-2# I'm not a physicist and I used to say I'm here to develop the toys for physicists. So I'm involved with the machines. There are several people at CERN who decide what has to be done on the physics' side and we are responsible for developing the tools for these people to carry out their research.

#00:55:37-3# There is not really hierarchies here at CERN, at least thats my feeling, there are people from the physics side deciding what has to be done and we're here to provide them with the required tools to be able to investigate what they are looking for so there is no real hierarchies, there are different specialties at CERN in the technical part. Our section is MDT - my section leader  used to translate that to Making Dreams True. People ask for dedicated tools and we are here to try to develop these tools.

#00:56:32-8# We are presently working on the new generation of superconducting magnets using new technology - Niobium 3 Tin (Nb3Sn) superconducting cables - in order to reach a higher field that will be required for the upgrade of the luminosity of the LHC. The magnets presently installed in the LHC are based on Niobium Titanium technology and will reach the limit of the magnetic field that can be reached with this kind of superconductor.

#00:57:09-4# For example we're working on a new dipole with 100mm Bohr and 13 Tesla. and to give you a rough idea of what this represents , the required niobium cable to produce one coil is around 100,000 Swiss francs per coil and we need 4 coils inside. You only need a few seconds to destroy the cable so, this is quite difficult to deal with.

MARTA BAJKO

#01:01:44-5# We're working with superconductivity so the magnets we have to test have to cool down to a very low temperature, in this case to 4.2 kelvin or to an even lower temperature which is 1.9 kelvin. To do that you need a kind of thermos - a vessel that is well insulated from the outside which is very warm with respect to the magnet. Basically you have a 300 kelvin difference which would be the same as saying 300 degrees because its a relative number. So then you have to make sure the heat 'inleak' is kept to a minimum. So we build equipment which is essentially made up of a vessel itself in which we can put the magnet, then obviously we close it and we can access it by liquid which is in this case liquid helium and cool it down to 4.2k. Then we have to connect the power to this equipment because obviously the power generation is on the surface and a nominal 20 degree temperature is in the hall. So you have to bring the current into the magnet through this vessel. This vessel also helps us make the interface between the magnet and outside. And then obviously we have all the information coming out which is in the form of wires and we plug them into and then we have a control room behind us where we get the information visible on computers in a graphical way - in such a way that we can analyze it later on. So that is essentially what we have here behind me and basically you have 3 test stations of this type - so 3 units which are nearly independent - one from another.

#01:03:58-5# Well, my whole family is here cause I have to say my husband works at CERN, my husband works in the same area as me , so also magnets. And ok, that's life - we have a 3 year old child and she goes to the kindergarten at CERN. So in the morning we come as a family to CERN and are dispatched all over the 3 sites - my husband works in the French area, I work between the swiss part and the french part (still in french territory) and my daughter is on the Swiss side in Kindergarten. My husband also has another son - he's in the control room. I also have a brother-in-law in the ATLAS detector so, we are really all a family.

#01:05:09-1# Well, when you say we have to leave some space for the imagination, you assume that what we are doing is enough to understand the world - how the universe works - I'm not so sure. I think that..... We are in a territory where we are so close to understanding the complete picture that it has become very very hard to improve. I'm not at all convinced that the big steps we make are big enough to get rid of the space that remains there. I think we're on the top but now it progresses very slowly - I think we are still far away, I'm not sure it will come next year where we explain Higgs and the dream is real. No, I think we will find elements that will bring us closer - that's the idea I believe - but I'm not convinced that we will understand the complete picture.

HERWIG SCHOPPER

#01:08:13-4# You might know there is a principle called the Anthropic Principle which says nature and the laws of nature were designed only to make it possible for humans to exist. But I doubt. Of course, we also realize that science and physics is only one perspective of understanding reality and nature. I had a long discussion here with the pope, when he visited CERN, not the present or previous pope - it was John Paul II. I discussed with him, can there be a conflict between science and religion and we agreed, no, there cannot be a conflict. He agreed to that. So I asked him, if you agree why don't you rehabilitate Galileo?

#01:09:27-3# Look, if you have a plate, a dinner plate, and you look at it from the top, you would say its a circle. If you look at it from the side, you wouldn't say its a circle - you would say it's a line. So they are 2 conflicting perspectives and you could ask forever 'Is it a line, or is it a circle?' So that's what religion and science does with reality, they are looking at different projections of reality. They see it differently but they are 2 projections of the same reality. It takes a long time to clarify a certain concept. How do we define something. The real imaginative nature of science is in creating a consensus which is necessary to find the laws of nature. Maybe these concepts are not unique - there might be other ways to describe nature by different concepts.