The doctrine that at least certain ideas (e.g., those of God, infinity, substance) must be innate, because no satisfactory empirical origin of them could be conceived, flourished in the 17th century and found in RenÃ© Descartes its most prominent exponent.
Local Curvature of Space. According to Einsteinâs theory of general relativity, massive objects warp the spacetime around them, and the effect a warp has on objects is what we call gravity. So, locally, spacetime is curved around every object with mass. Overall Curvature of Space
Observational astronomy is a division of the astronomical science that is concerned with recording data, in contrast with theoretical astrophysics, which is mainly concerned with finding out the measurable implications of physical models.s a science, the study of astronomy is somewhat hindered in that direct experiments with the properties of the distant universe are not possible. However, this is partly compensated by the fact that astronomers have a vast number of visible examples of stellar phenomena that can be examined.