From the Introduction: Earth is overpopulated. Has been for as long as anyone alive can remember. Nations don't fight over moral disagreements anymore, or even political. They fight over food and space for their people to live. Pollution has devastated large portions of the world, lowering even further the available space to inhabit. We tried for many years to find a way to colonize space. Every attempt failed drastically, ending every time with the death of all volunteers. Things were looking bleak. Then some of our scientists discovered Eden. This wasn't a new planet, but a dimension the runs perpendicular to our own. In the place where the two meet is a natural weak spot. However, we found we couldn't colonize Eden, at least not the way we wanted, without endangering all who already lived there. That's when the Janus Project began and the creation of the Reactors became necessary...