Just wondered if the following extract is historically correct ... Einstein's and now main stream's current gravity theory is based on the belief that if you were accelerating in a space craft you wouldn't be able to distinguish between this experience and that of gravity. It was then decided that acceleration and gravity were the same. The next challenge was to explain how we could be accelerating upwards with 1g without apparently moving and even more of a challenge to explain why two masses tend to move together. For acceleration, you need a spatial component and a time component hence the evolution of the idea of 'spacetime', a bundling of these two dependent dimensions together. Gravity is explained as a natural property of matter which has the ability to warp or distort this 'spacetime'. The passage of time varies the closer you get to a gravity source and the geometry of the spatial component changes whereby our idea of a straight line becomes more and more curved. Is this ok?