The ILC physics working group is a mixture of experimentalists and theorists
mainly working in Japan. It has its origin in the previous LC physics study
group and has been reformed with the initiative of a JSPS Creative Scientific
Research project: "Research and Development of a Novel Detector System for the
International Linear Collider". The working group is, however, formally
independent of the JSPS project and is open to everybody who is interested in
ILC physics. The primary task of the working group is to reexamine the ILC
physics in the context of the expected LHC outcome and to further strengthen
the physics case for the ILC project. The topics covered in the working group
activities range from key measurements such as those of the Higgs self-coupling
and the top Yukawa coupling to uncover the secrets of the electroweak symmetry
breaking to various new physics scenarios like supersymmetry, large extra
dimensions, and other models of terascale physics.
The working group has held ten General Meetings in the period of May 2007 to
June 2009 to discuss the topics mentioned above. This report ummarizes the
progress made in this period and sets a milestone for future developments in
ILC physics