what happens when ordinary matter is sogreatly pressed that the electrons form a relativisticdegenerate gas, as in a white dwarf star? what happens when thematter is pressed even further so that atomic nuclei overlap toform superdense nuclear matter, as in a neutron star? what happenswhen nuclear matter is heated to such great temperatures that thenucleons and pions melt into quarks and gluons, as in high-energynuclear collisions? what happened in the spontaneous symmetrybreak-ing of the unified theory of the weak and electromagicinteractions during the big bang? questions like these havefascinated us for a long time. the purpose of thiook is todevelop the fundamental principles and mathematical techniques thatenable the formulation of answers to these mind-boggling questions.the study of matter under extreme con-ditions halossomed into afield of intense interdisciplinary activity and global extent. theanalysis of the collective behavior of interacting rela-tivisticsystems spans a rich palette of physical phe
