Originally Posted by Aenlic
Umm... no. You are describing part of the classic controversy between the concave, convex and flat descriptions the geometry of space-time. The idea that gravity will eventually slow down the expansion of the universe until it contracts into a reverse Big Bang is called the convex geometry model, or the closed or positive curvature model. On the other hand, if the universe expansion slows and then stops but does not then collapse, this is the flat geometry or open model. A third possibility postulated after Hubble was a concave, or open model which had the universe expanding forever, or the heat death model. This modeling of the universe expansion, after the Hubble Law, was considered the big problem in cosmological physics for 80 some years. The actual problem turns out to be something quite different, which I'll get to presently.
Einstein added what he called the cosmological constant to his equations because the equations were predicting an expanding universe. He felt this was in error and so created the cosmological constant to fudge a static universe. At the time, the universe was thought to be static, as in unchanging, not expanding, or flat. Hubble's discovery of the red shift around 1929 or so, also known as Hubble's Law, showed that the universe was, in fact, expanding. This led to the Big Bang theory. Einstein decided he'd made a mistake in adding the cosmological constant and called it his greatest error. This appears to be where your knowledge of modern cosmology stops.
One of the most important details to Hubble's Law was that the expansion is uniform. The matter in the universe isn't expanding. Space is expanding with the matter carried along. This is a difficult concept for many to grasp. The matter in the universe didn't fly apart in the Big Bang, speading out into the universe. The universe itself flew apart in the Big Bang and continues to do so. The universe is expanding uniformly at all points away from all points. There is no edge to the universe. Another difficult concept to grasp. This was the standard view in cosmology; but it still left open the argument about convex, concave and flat curvatures.
But it gets worse. New data, within the last 6-7 years and being confirmed almost daily as our ability to observe improves, shows that the expansion of the universe, while uniform, is not constant in rate of expansion (as would be predicted in an open, concave model) or slowing down (as would be predicted by a closed, convex model or an open, flat model). The universe is expanding at an increasing rate. In other words the expansion if getting faster and faster, but is still uniform. And not only is the rate of expansion increasing; but the distribution of matter in the universe doesn't match the mathematical predictions of a uniform expansion of matter affected by gravity. There are clumps. There is missing mass, the so-called dark matter. Something is causing the universe to expand ever faster, the so-called dark energy.
The idea that the Big Bang was just one in a never ending series of expansions and contractions has been disproven by observation.
Initially, as the universe expanded, gravity acted to slow down the expansion. But... a point was reached, somewhere at about half the current age of the universe, at which something now called "dark energy" was able to exert more effect than gravity. It can almost be thought of as a repellant force. The result was that the force of the dark energy exceeded the force of gravity and the expansion of the universe began to speed up. It is still speeding up. The universe is flying apart at an ever increasing rate, exactly opposite of gravity pulling the universe back together as you stated. This dark energy, or more precisely the force which the postulated dark energy describes, was predicted by Einstein as his cosmological constant. In effect, his greatest mistake is beginning to look more and more like it was bang on.
You're about a decade or more behind in your cosmological theory, Legio. The study of Cepheid variables, the Sloan Digital Star Survey and more are all relatively recent and contradict your assumptions which seem based on decades-old theories. You're in serious need of some hard studying. Increased rate of universe expansion, dark matter, dark energy, partial dimensions, neutrinos with mass, accelerons, string theory, super string theory and more have overtaken the 70-some odd year old theory of an expanding universe affected mostly be gravity, whether convex, concave or flat. :wink: