The flat '''curvature of spacetime''' does not reqire all of [[curvatures of spacetime]] to disappear since they, being non zero, may combine together in flat [[spacetime]] as it may happen in stationary universe where [[curvatures of space]] together with other [[curvatures of spacetime]] may produce a flat [[spacetime]]. | The flat '''curvature of spacetime''' does not reqire all of [[curvatures of spacetime]] to disappear since they, being non zero, may combine together in flat [[spacetime]] as it may happen in stationary universe where [[curvatures of space]] together with other [[curvatures of spacetime]] may produce a flat [[spacetime]]. |