What is the biggest discovery so far

"Greatest Discovery of the Century"

Deutsche Welle: Why don't physicists really want to decide whether they have found the Higgs particle or not?

Joachim Mnich: We are always a little careful. We can safely say that we have found a new particle. But to be sure that it is actually a Higgs particle, we still have to study its properties. We haven't had the opportunity to do this yet. The last data is only two weeks old.

Is that a sensation that we are experiencing here?

I consider this to be the greatest discovery of physics to date in this century. I am convinced that we saw a Higgs particle. But even if it was something else, that would be a sensation. Because there is absolutely no room for that in the model that we have today of the fundamental building blocks of matter. So that would definitely be world-shattering news.

Why exactly is it all so spectacular?

Over the last few decades we have developed a model that explains the components of visible matter. In this model, however, one assumes particles without mass. But they have a mass - thank God, otherwise the universe would not be as we know it today. Peter Higgs and other researchers developed a mathematical trick in the 1960s to reconcile the two. Using the Higgs boson, which we have in all probability now discovered.

What does this discovery mean for us?

With this discovery, we have taken an important step towards understanding the universe. For the first time, we now have a key to understanding the concept of mass. That is far from the end of the road, because Higgs could not explain why the particles have different masses. But it's the right approach. We are on the right path.

What could be the practical use of such a discovery?

Difficult to say, because this is about basic research. We are driven by curiosity and want to understand what holds the world together. It is not yet possible to foresee where the practical use will be. Maybe a look into the past will help. When the first physicists built particle accelerators 50 years ago, they did it for precisely this reason. Today we even find particle accelerators in hospitals, where they are used to treat cancer. People didn't even think of that 50 years ago.

Professor Joachim Mnich DESY

Now the CERN physicists are saying that more data is needed to be able to say clearly whether it is the Higgs particle. Was the press conference a snap shot to get ahead of other research teams in the USA?

I do not think so. I am frankly impressed. I did not expect that the experiments would be ready by now. This is because the research teams have refined their analysis methods very much. That is why one has already crossed the threshold to discovery. Our colleagues in the USA are still a long way from achieving this level of measurement accuracy.

Can you review that again: What exactly did the researchers at CERN do?

We shoot protons - the smallest particles - at each other and try to generate energy in the smallest of spaces. This is how we create the conditions that existed shortly after the Big Bang. The energy is then so high that particles like the Higgs particle are generated. The Higgs particle decays after a fraction of a second. In order to discover it, we have to measure the decay products with our detectors and draw conclusions from them. This is the only way we can prove that a particle is generated there that cannot be explained by other processes. This is fundamental quantum mechanics and it is dominated by probabilities and statistics.

Do you want to show a success to justify the high costs?

Of course we are happy to be able to justify the high costs that CERN causes with our discoveries. But that is not the reason for the present presentation. Experiments have shown that it is a discovery. Whether it's a Higgs boson or something else at least as exciting, we have to investigate a little more closely.

When the Higgs boson is found, CERN will actually have reached a milestone. What will the physicists research there next?

In the last few years everything revolved around the search for the Higgs particle. We knew that we could answer this question with the LHC particle accelerator and these experiments. This is how we designed the accelerator and detectors many years ago. The discovery of a Higgs boson means that we have come closer to the answer to the question of mass. That doesn't mean we've cleared the question, because Higgs and his mechanism don't explain why the particles have the mass that they have.

It doesn't solve many other questions either. Our model can only explain the visible matter in the universe. However, 96 percent of the matter is not visible, it does not even appear in the model. We cannot explain why there is only matter in the universe and no antimatter. Actually, matter and antimatter should have completely annihilated each other in the Big Bang. These questions will come to the fore in the future and the Higgs particle can help us find an answer.

The interview was conducted by Michael Hartlep.

Professor Joachim Mnich is a physicist and works at the German Electron Synchrotron DESY in Hamburg. In the course of his career he spent many years at the European research project CERN, where he explored the world of the smallest particles. Since 2008 Mnich has been director of the field of high energy physics and astroparticle physics at DESY.