I know negative curvature of spacetime is close to impossible.. but reading about dark energy and how it is repulsive... I'm trying to find illustrations of what would happen when spacetime curvature is negative (locally as whole cosmos having negative curvature is different concept than local negative curvature, right?).. or beside negative curvature.. what form must the stress energy tensor be so instead of objects attracting via gravity.. they become repulsive... I'm not trying to spread disinformation but just want to imagine how the geodesics and curvature would look like if there were antimass and negative curvature locally. I know antimass doesn't exist. But I just want to visualize how the spacetime diagram would look like when it is negative. Or does the question make any sense at all? Just give me a youtube link for some illustration.. thank you.