Men obviously do not like prisons; or anything that can limit their lives. They do not like boundaries or constraints imposed on them by the brevity of their lives, or those imposed on them by physics. So, all the human adventure is made of escape attempts: thus, man lives longer and longer, knows the entire globe, learned how to fly, and explores the universe.
However, he met, much to his surprise, a century ago, a prison that he was told was irreducible: according to the theory of relativity, developed in 1905, he would never be able to go faster than the speed of light in a vacuum. More precisely, once we accelerate protons or electrons, their speed increases less and less and never reaches that of light. And even if it is a very distant limit, it is for man, unbearable.
So it is necessary to understand the importance of the result obtained by chance at the European Centre for Nuclear Research in Geneva: the high-energy neutrinos (very particular particles, whose mass is less than 1 electron-Volt, and which interact very little with matter), would have traveled underground the 730 kilometers separating the French-Swiss border from a neutrino detector installed in the Gran Sasso mountain near Rome, at a speed of 6 km/s faster than that of light. That is to say they would have arrived 20 meters ahead on the light! Not believing themselves in their result, researchers have been carrying out the experiment for the last three years, observing more than 15,000 neutrinos, checking measuring instruments, the length of the road, even taking into account the possible influence of the continental drift and the earthquake in L’Aquila. Nothing helped: neutrinos have traveled faster than light.
Pending further checks, the United States and Japan have confirmed this unlikely result, one must ask what such a transgression would mean: how the neutrinos could have escaped such a limit, imposed by the theory of relativity, whose validity is well proven in our universe in 4 dimensions (with time)? They could have done it only by escaping in another space, with more dimensions than ours, and by finding there a shortcut bringing them back faster to our universe.
Fascinating hypothesis, which would open, if confirmed, many avenues. First to address some major enigmas of modern science, which cast doubt on current theories: why is the physics of gravitation different from the other two fundamental interactions (electromagnetic force and nuclear force)? How to explain that an important mass is missing in the Universe? How to describe the state of matter in a black hole? How to tell the first millisecond after the Big Bang?
Then, perhaps, to escape one day from the ultimate prison, closely guarded, that of causality, which forbids any event to occur before its cause. And which makes it impossible to travel in time, neither forward nor back. Leaving prediction, for a long time to come, to remain the most fascinating activity of humanity.