The Redemption of Time

At the end of the fourth year of the Crisis Era, Yun Tianming, riddled with cancer, chose to end his life. But death is no release for Yun Tianming - merely the first step in a journey that will place him on the frontline of a war that has raged since the beginning of time. As Yun Tianming lay dying, his brain was extracted from his body, flash frozen, put aboard a spacecraft and launched on a trajectory to
intercept the Trisolarian First Fleet. It was a desperate plan, almost certain to fail. But there was an infinitesimal chance that one-day Tianming may, somehow, send valuable information back to Earth. And so he does. But not before he succumbed to subjective centuries of alien torture and betrayed humanity.