Determination of the Sign of the Spatial Curvature of the Universe Based on Friedmann’s Equations and Experimental Data

It is a commonly accepted fact that the spatial curvature of the universe is very small or zero. Mission Planck measured a value very close to zero for the curvature term in the Friedmann equation. Another issue is determining its sign. From a theoretical physics perspective, the value of k can be -1, 0, +1, and depending on this value, the sign of the curvature term in the Friedmann equation changes. To date, no commonly accepted conclusion has been reached regarding this value. Likewise, the meaning of this sign implies different characteristics of the universe: finiteness, infinity; boundaries, unlimitedness, etc. In this work, we propose a value of k = +1, which is the same as a positive sign for the value of the spatial curvature, which makes the experimental results obtained, regarding the change in trend of the Hubble parameter 6 billion years ago, consistent with the Friedmann equations.

Keywords: Cosmos, General Relativity, The Universe on Large Scales, Spatial Curvature