Hello everybody, this is my first post to the forum. I am trying to learn concepts in physics at the moment. According to the theory, the concentrated mass of a black hole warps space-time so much, that not even light can escape the event horizon. I have a thought experiment. Say, half the mass of a black hole "instantaneously vanishes". According to general relativity, the nature of warp of the space-time surrounding the event horizon should change because of the new mass, giving rise to a gravitational wave at the instant of the change in mass. What bothers me here is that a change in the interior of the black hole can effect the space-time outside the event horizon. This would require a transfer of infomration form the interior to the surrounding space. Since, even information cannot travel faster than the speed of light, I struggle to see how space-time outside the event horizon could be effected by such a change. I understand that this is a thought experiment and am open to the validity of the instantaneous change in mass being questioned. It was intended along the lines of 'If the Sun disappears, the Earth would still continue to orbit for 500 seconds before it is cast into a tangential trajectory'