I borrowed the title from Pythagoras and Kepler. In my score, what interested me was not the theoretical aspect of their work, but rather the poetic and metaphorical aspect of their thoughts, regarding the various geometrical lines drawn by the stars in the universe. Throughout the score, I also tried to preserve the idea of the three dimensions of space, by writing a purely instrumental work, and by creating true sonic perspectives, without making use of electroacoustic spatialization, or even the specific positioning of the musicians in the concert hall. The first part, "Symmetries", develops the interlacing of multiple "ribbon figures" (in arabesque shape) split by means of various types of mirrors (flat, oblique or distorting). The evolution of these "ribbon figures" is controled by a small "3a-table" software created during a work with OpenMusic at IRCAM. The second part, "Malaise of Adolescence", draws an endless straight line. In this part, I attempted to realise what Giacinto Scelsi sought to include in his music: "the sound is spherical and round". A number of jarring 'shakes', as violent as they are brief, sometimes disturb the apparent tranquility of this section. Finally, "Quantic Movements" (the third and final part), takes us to another universe, that of the infinitely small, where the universe was probably created. Other lines were drawn, and these lines contain their own spherical movements, revolving independently on themselves. The ensemble evolves in a sort of beaded canvas, demultiplied, and ends in the centre of a galaxy. Here, in this scorching nucleus, the infinitely small and the infinitely vast meet and join.