EXPANSION SPEEDS AND ACCELERATIONS OF THE UNIVERSE IN FIVE GENERAL COSMIC MODELS |

The horizon expansion speed, horizon expansion acceleration, horizon volume speed, and horizon volume acceleration of the universe expansion were all proposed as new cosmological quantities. These parameters have been studied in five different cosmic models. In these theories, the distributions of the universe's space expansion speed decline until they reach minimal values, then slowly climb until Capture8.PNG Gyr, and hence rise far faster. The minimal space expansion speed in the reported general model is Capture9.PNG Gyr. In general models, however, the distributions of the universe's horizon expansion speed constantly decrease with cosmic time. At this time, Capture10.PNG is the observed generic model. The distributions of the horizon volume speed of the universe expansion, on the other hand, rise slowly until Capture11.PNG yr, then rapidly ascend to maximum values, and then gradually decrease to zero. At this time, the highest horizon volume speed in the observed general model is Capture12.PNG Gyr, while the maximum horizon volume speed in the observed general model is Capture13.PNG Gyr. The distributions of the universe's speed expansion acceleration in general models show a steep rise towards 1.PNG and stay very close to this value, then increase very slowly up to 2.PNG Gyr, then rise more rapidly, but after Capture14.PNG Gyr they surge significantly faster. Nonetheless, in general models, the distributions of the universe's horizon expansion acceleration show a sharp ascension towards Capture15.PNG and remain close to this value after Capture16.PNG Gyr. Finally, in general models, the distributions of the horizon volume acceleration of universe expansion decrease with time unit. Capture17.PNG They stay close to Capture18.PNG in Gyr. At this time, Capture19.PNG is the observed generic model.

The four new cosmological quantities are discovered to be significantly related to the distribution of the universe's total pressure.

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