Field theory is a fundamental basis of moden theoretical physics, in particular in elementary particle physics, nuclear and hadron physics and condensed matter physics. The mathematical framework of field theory can be shared and applied beyond the boundaries among various subjects in physics. Our aim is to reveal hidden theoretical structure of nature at various scales, by using powerful tools of field theories.

The most advanced formulation of physics is quantum field theory, which combines two basic principles of modern physics – relativity and quantum theory. The rich structure of it provides surprising new understanding of nature. String theory is the most promising candidate of the "unified theory" which unites the quantum field theory of elementary particles and the gravity theory of Einstein. The research of string theory brings about deep and hidden new aspects of nature and field theories.

Quantum field theory, string theory and related theories.