# Is a planets orbit really a straight line through curved spacetime? [duplicate]

My understanding is that general relativity concludes that gravity isn't real because it does not exist in all frames of reference. Also that mass and energy warp spacetime into a curved geometry. Does that then mean that objects in orbit are actually traveling in straight lines in curved spacetime?

• @Wjdavis5: this is a semantic nicety. Because motion is explained by the geometry some like to claim that gravity isn't a force. This is a bit silly because the mass times the norm of the four-acceleration is non-zero in loads of situations, and to me $ma$ certainly seems equal to $F$. – John Rennie Jun 9 '15 at 16:34