Is the Universe curved?

Building on some findings and postulates some scientists recently announced, the question on whether the universe is curved may be better represented and may not so readily be ruled out. This would be more recent since the paper of LIddle and Cortes of 2013. It was earlier also worked on by Alexander Friedmann, ca. 1923.

The concept now is that the universe has a flat plane geometry. The edge, though, is not seen, it remains unknown. It is possible the universe does have curvature but the proof may have to be found out by the edges. It will depend on the energy and power distribution and whether that will always hold throughout its evolution. Quite a number of scientists say that with new, sensitive instruments, there are more objects found in the explorations that show some curving in various places. Riemann had developed the concepts of curvature, which breaks the ideas of viewing the cosmos two dimensionally and flat as if there is only the perspective of a flat surface upon which everything is perceived.

Indeed, it was assumed that light travels linearly and straight. However, it is found the universe has curvature. Thereby, light cannot be assumed to always travel linearly if it is to reach all points. It must also follow the curvatures.

Many civilizations, ancient and modern, hold the earth is round, not flat. In early Greek thinking, some e.g. Leucippus, Democritus, veridically observed that many objects are viewed as curved or round on earth. If they are round, then it must be based upon that there is curvature that the objects reflect or they would not assume such configuration. Ancient studies also show they saw the firmament containing round bodies, stars, planets, currents, horizons. This of course is attributed to the activity of gravity. But also in the ancient day, they did not propound the force of repulsing  antigravity and detail what effects that may have. (They were earthbound and could not perceive what lay beyond the planet in detail.) The idea of curvature seems to persist through time.

Some state now that there could be detected a mild bow shaping in the cosmos.

"There is a priori no clear prescription for the choice of vacuum in cosmological  backgrounds. Nevertheless, as our universe is approaching a de Sitter space-time with very small curvature, we assume that the flat space-time vacuum structure is not altered..."-Saulo Carneiro, Nov. 2017. And R.M. Wald, 1994 and 2008 paper.

(work in progress, more will be entered)