Recent measurements have shown that the ratio of the actual density of the University to the critical density of the Universe is approximately 0.3, meaning that over very large distances, the expansion rate of the Universe looks decelerated.
The critical density of the Universe is a key parameter in cosmology, representing the density required for the Universe to be flat and neither expanding nor contracting over time. The measured ratio of actual density to critical density, denoted by the symbol Omega (Ω), helps classify the fate of the Universe. When Ω is less than 1, as in this case (Ω ≈ 0.3), it indicates an open universe. This implies that the overall density is below the critical threshold, leading to a decelerating cosmic expansion.
In summary, recent observations suggest that the Universe's density is approximately 30% of the critical density. This subcritical density signifies an open universe, where the expansion rate is decelerating over vast distances.