Hello everybody ! This is my question: Suppose you have a mass m0 inside an ellipse (at rest). Suposse someone see it from another frame, from this frame he will see the ellipse contracted. I know there's no black hole, but, how can explain our observer this result? I'm trying to see only the frame of our observer, I know he knows about relativity and he can calculate our m0, and our r0 (ellipse's radius at rest), and then conclude there's no black body. But what is seeing at really our observer? I mean, he can explain it seeing our viewpoint and noting that there's no black hole, but how can explain it from his own frame? Thanks ! PS: I have read many times articles like: If you go too fast do you become a black hole? http://www.math.ucr.edu/home/baez/physics/Relativity/BlackHoles/black_fast.html and again, I don't think there's a paradox here, I'm just trying to see what is seeing our observer. Maybe is analogous to: When we see a moving frame, we see their atoms contracted in the direction of motion. Then the orbitals don't follow the expected symmetry, how can be stable these "deformed" atoms?