午夜福利1000集合

Next month Fabiola Gianotti takes over as head of at the at CERN in Switzerland. The largest experiment of its kind, it could answer some of the mysteries of the universe. She talks to Anil Ananthaswamy about dark matter and deep truths

What are your thoughts on becoming the first woman to head a particle physics experiment at the LHC?
CERN is such a rich environment: there are people from all over the world, young students work with established scientists and Nobel prizewinners. So geographical origin, age and gender make no difference here. I don鈥檛 feel there is anything special about a woman leading a big scientific project. On the other hand, I hope that as a woman scientist who has achieved a level of visibility in a big experiment like , I can be an encouragement to young women who are thinking of a scientific career.

Why did you decide to become a particle physicist?
I came to physics from very far away. When I was a young girl, I loved art and music. I had been studying piano quite seriously at a conservatory and had taken courses in high school targeted towards literature, languages like ancient Greek and Latin, philosophy and history of art. I loved these subjects but I was also a very curious little girl. I was fascinated by the big questions. Why are things the way they are? This possibility of answering fundamental questions has always attracted me 鈥� my mind, my spirit, everything.

So, when I had to choose what I wanted to do with my life, I thought that physics could answer these big questions in a more concrete way than philosophy. I was right 鈥� in that I鈥檓 very happy now.

Give us a sense of the size and scope of ATLAS.
The ATLAS collaboration consists of almost 3000 physicists from 169 institutions, 37 countries and five continents. ATLAS is the biggest detector ever built at a particle collider and its spectacular size strikes people immediately when they visit the underground cavern it is housed in 鈥� it鈥檚 as big as a five storey building. This size is combined with an enormous complexity. There are 100 million independent electronic signals that we need to record in order to reconstruct the hundreds of particles produced in every proton-proton collision. The trajectories of the particles must be reconstructed with micrometre precision. This amazing combination of size, complexity and precision has made the technology very challenging. ATLAS and indeed the other detectors at the LHC are instruments without precedent.

What are the key goals of ATLAS?
ATLAS will sift through particles created by extremely high-energy proton-proton collisions. We are starting on a fantastic scientific journey. We believe that at this energy scale, new physics should manifest itself, physics beyond the so-called standard model [which explains all known particles and the forces that act upon them]. We expect to find answers to some fundamental questions and mysteries, many of which have been with us for decades. For instance, what is the origin of mass? It鈥檚 a question related to the existence of the Higgs boson. Are there other forces of nature, in addition to the four forces we already know of? Are there additional dimensions of space? What is the composition of the universe鈥檚 dark matter?

What would you personally like to see ATLAS discover first?
Dark matter. I would be very, very happy if we discover the particle that explains 20 per cent of the universe鈥檚 composition. Accelerators like the LHC allow us to study the infinitely small 鈥� the basic constituents of matter 鈥� and this can tell us about the structure and evolution of the universe, stressing the link between the infinitely small and the infinitely big.

Have you thought about what would happen if no new physics is discovered at the LHC?
It is a good question, but it鈥檚 difficult to answer. Based on what we have learned from experimental and theoretical work over the last few decades, there must be something new at the energy scales that the LHC will offer. Perhaps there will be just one Higgs boson, or a new mechanism playing the same role, but we expect more. We know that the standard model is not a complete theory of elementary particles, because it cannot answer all our questions. We expect it to start to break down at the energy scale of the LHC. There must be new physics there. Perhaps they won鈥檛 be the answers that we have in mind, but there must be answers. Nature could well present us with surprises and this will be one of the most exciting possibilities. After all, research is about looking for something that we don鈥檛 know a priori.

鈥淲e have to find something, and nature could well present us with surprises鈥�

What has it been like working on ATLAS?
Building the LHC and experiments like ATLAS is an unprecedented scientific, technological and human adventure. What makes my life as a scientist at CERN so special is the combination of three elements. One is the exciting physics goals. Then, to address these questions, we had to develop high-tech instruments which are at the cutting edge of technology in various sectors, from electronics to cryogenics, and which have spin-off benefits to society. Thirdly, these projects have been carried out in an international environment, with physicists, engineers and technicians from all over the world, bringing nations together through science and breaking political barriers. In our project, we have people from countries that are historically not the best of friends.

What鈥檚 the mood at CERN, given that the start of the LHC got delayed?
The inauguration of the LHC on 10 September was a big success, there was a lot of excitement. And then 19 September, when the accident happened, was like a cold shower. There was of course big disappointment, especially among the younger people, who were so excited and so happy during the first few days when the LHC was circulating single beams. On the other hand, this is a very difficult project technologically. It was started almost 20 years ago and will last for another 20 years, and such hiccups have to be taken into account. We are on a path which otherwise has been very successful until now, and will be very successful. We just have to be a little bit more patient.

The LHC and ATLAS could potentially reveal some deep truths about how the universe works. What do you feel when you think about it?
Feelings of excitement, of course, and the awareness of being close to something very important and great for humankind. Fundamental research is a duty and a need of human beings. The 13th century Italian poet Dante said that we were not created to live as animals but to pursue virtue and knowledge. As human beings, the pursuit of fundamental research and knowledge is a need for us, which separates us from animals or vegetables. It is like the need for art. Research bring knowledge, and knowledge brings progress, always.

If we discover something fundamental at the LHC, it will be a bit like going to the heart of the universe. When you are getting closer to the fundamentals, to the basic questions of where the universe comes from and where it is going, there鈥檚 a very special feeling.

Read more about the world鈥檚 biggest experiments: 鈥�Monsters of the universe鈥�