The FORCE mission: focusing on relativistic universe and cosmic evolution

We present the concept of a future Japan-lead X-ray mission, FORCE (Focusing On Relativistic universe and Cosmic Evolution). FORCE is characterized by broadband (1-80 keV) X-ray imaging spectroscopy with high angular resolution (<15"). The sensitivity above 10 keV will be 10 times higher than that of any previous hard X-ray missions. FORCE will trace the cosmic evolution by searching for ``missing black holes'' in the entire range of their mass spectrum and investigate the nature of relativistic particles at various astrophysical shocks by observing their non-thermal X-ray emission.