Preamble Human beings, this infinitely curious and complex entity, have since the dawn of time tried to locate and define themselves in relation to what they considered to be infinitely large and infinitely small. His intelligence combined with his perspicacity, allowed him to gradually unravel the secrets of creation to all those around him.The sciences of the cosmos and the conquest of space, excite and enthuse the man who looks at the stars. The infinitely large fascinates him with the beauty and the diversity of the images collected by astronomers: vast spiral galaxies, multicolored interstellar clouds, astronauts walking on the lunar soil, astonishing diversity of planetary surfaces captured by space probes.... All these marvelous photographs rich in detail, stimulate our imagination, incite us to dream of alien worlds and excite our greed to penetrate and explore the infinite spaces of our Universe The other infinite is more mysterious and more austere: the images of atomic particles belong to the infinitely small, this field is that of particle physics. Its observation instruments are electron microscopes and gigantic colliders. However, these devices do not provide the public with such spectacular images as those of astronomical telescopes. And yet we are all the more tied to this universe of elementary particles that we are made of, as well as all the rest of the Universe. This is why I invite you to accompany me on this fabulous journey to the ends of matter. We will discover an infra-terrestrial world where our common sense is challenged and where matter flirts with emptiness.We will then try to go back in time from the confirmed hypothesis of the extension of the Universe, to the approach of time Zero and the resulting limits for distance, density, temperature and l 'energy. At this point we will reach the Planck wall beyond which time and space no longer exist. Finally, we will ask the question: where is the universe going? Will its extension come to an end? Which ? How to explain and prove it? We will try in this book, to find the answer to all these questions, so follow us and be part of this extraordinary journey.Once back, we'll try to wrap up.Amor Abbassi