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'''Curvatures of spacetime''' is a set of 10 various curvatures that may be specified as components of a curvature tensor that describes the [[curvature of spacetime]] (the same thing as the [[curvature of 4-space]]).  

'''Curvatures of spacetime''' (note the plural) is a set of 10 various curvatures that may be specified as components of a curvature tensor that describes the [[curvature of spacetime]] (the same thing as the [[curvature of 4-space]]).  

[[Curvature of spacetime]] (singular as opposed to plural "curvatures") is something that describes a fact that some 4-dimensional space is curved. It can't happen though in a stationary universe since the [[spacetime]] of stationary universe has to be flat (or [[Minkowski]], which is another word for the same thing). In particular the '''curvatures of spacetime''' may describe the curvature of common 3-dimenssional space (given by x,y,z vectors) being a part of this 4-dimensional spacetime (in this case given by t,x,y,z 4-vectors), which is a chance for messing things in astronomy when one says the "[[curvature of space]]" but means the "[[curvature of spacetime]]" (that is then called simply the [[curvature of 4-space]]) that has to be flat in stationary universe though having its non zero '''curvatures of spacetime''' adding to the flatness of whole [[spacetime]].

[[Curvature of spacetime]] (singular as opposed to plural "curvatures") is something that describes a fact that some 4-dimensional space is curved. It can't happen though in a stationary universe since the [[spacetime]] of stationary universe has to be flat (or [[Minkowski]], which is another word for the same thing). In particular the '''curvatures of spacetime''' may describe the curvature of common 3-dimenssional space (given by x,y,z vectors) being a part of this 4-dimensional spacetime (in this case given by t,x,y,z 4-vectors), which is a chance for messing things in astronomy when one says the "[[curvature of space]]" but means the "[[curvature of spacetime]]" (that is then called simply the [[curvature of 4-space]]) that has to be flat in stationary universe though having its non zero '''curvatures of spacetime''' adding to the flatness of whole [[spacetime]].