Elementary particle physics

The question of what matter is made of at the most elementary scale and what role fundamental interactions play has always sparked human curiosity. This is all the more true since we know that the elementary particle physics was a crucial part of the evolution of our primordial universe. Studying the infinitely small will, therefore, allow us to better understand the infinitely large.

In this course, we will discuss elementary constituents of matter, such as quarks or leptons, and the different forces at play: electromagnetism, strong, and weak interactions. This ensemble of particles and interactions, which is called the "standard model", cannot be described and understood without the strange and fascinating framework of quantum theory, to which we must add the concepts of relativistic mechanics. One particular example that perfectly illustrates the mysterious aspect of elementary particles are neutrinos. These particles are produced in gigantic quantities in the heart of the Sun as well as in nuclear power plant reactors or in the upper layers of our atmosphere. They almost interact with nothing, have almost zero mass, and have no electric charge. This does not prevent physicists from studying these ghosts of the infinitely small by making them "oscillate" over distances of more than 290 kilometers.

An important part of the course will be devoted to the concepts of modern physics (symmetry, conservation laws, internal degrees of freedom and additional dimensions, ...) successfully used for infinitesimal scales, for the spectacular results obtained at particle accelerators, and for the great fundamental questions that we continue to ask after more than eighty years of research. The experimental demonstration and theoretical understanding of the difference between matter and antimatter represents an example of a major research challenge in this field of physics. Our primordial universe should have produced an equal quantity of matter and antimatter. This raises the question of the "disappearance" of antimatter in our present universe, which perfectly illustrates the close links between the physics of the two infinities.

The goal of this course is to introduce in a simple way the concepts of elementary particle physics without requiring complicated theoretical developments. First and second year quantum mechanics courses are sufficient prerequisites to follow this course without any particular effort.

 

Bibliographic references:
Introduction to subatomic physics

    • by André Rougé (2005)

Available on: Editions de l'Ecole Polytechnique.

 

Course language: French