This book is a course in modern quantum field theory as seen through the eyes of a theorist working in condensed matter physics it contains a gentle introduction to the subject and therefore can be used even by graduate students the introductory parts include a derivation of the path integral representation feynman diagrams and elements of the . G rickayzen greens functions and condensed matter h bruus and k flensberg many body quantum theory in condensed matter physics j rammer quantum field theory of non equilibium states g mahan quantum field theoretical methods fetter walecka quantum theory of many particle systems yu v nazarov ya blanter quantum transport. Why is quantum field theory of condensed matter physics necessary condensed matter physics deals with a wide variety of topics ranging from gas to liquids and solids as well as plasma where owing to the inter play between the motions of a tremendous number of electrons and nuclei rich. Various applications to quantum field theory and condensed matter physics have been outlined this work has been carried out in collaboration with m aizenman d brydges j and l chayes b