The fate of Lelouch as to weather or not he is still alive is based on your opinion. Even Goro Taniguchi, director of Code Geass, stated that the final scene was for the viewer to interpret. There is a number of evidence that people believe can prove that he is still alive, but that same evidence can be countered by other evidence. The bottom line is, Lelouch's death is a mystery and will remain a mystery until Gorō Taniguchi and Ichirō Ōkouchi reveal the ultimate proof that either Lelouch is alive, or that he truely is dead