We'll begin this section by picking up were we left off, completing our analysis of the big bang theory. Here you'll get a chance to see the two or three significant obstacles that prevent complete acceptance of it. Be that as it may, since it is the most popular theory right now, we'll also look at the consequences of how the universe will end, if the big bang theory is the correct one. It's not a happy picture and raises a number of philosophical questions about the meaning of human existence. But again, the view of how the cosmos will eventually end is a projection of a theory, not the way it will necessarily end.
Within the context of this section, we'll also examine another theory that has been put forth over the last decade, the theory of plasma cosmology. It supplies answers to some of the questions that the big bang has problems dealing with. And after all of that, we'll look at the three possible fates of the universe and the geometrical shape that coincides with what cosmology knows about the structure of the cosmos at the beginning of the twenty-first century.
It's Bigger Than We Thought
In 1986, Brent Tully discovered that almost all galaxies within a distance of a billion light years of the Earth are concentrated into huge ribbons of matter that are called superclusters. These clusters are about a billion miles long, 300 light-years wide, and 100 million light-years thick.
There are two basic assumptions in conventional cosmology that new observations have posed problems for:
- The universe is, at the largest scale, smooth and homogeneous.
- This smooth universe is dominated by gravity alone and therefore must either contract to or expand from a single point, a singularity.
When superclusters were first discovered, many astronomers and cosmologists couldn't accept their existence and dismissed them as errors in calculations. Years of hard work by the astronomers who found them were ignored to save the big bang theory. But time and the Hubble telescope have vindicated these people and have left the others scratching their heads. Astronomers are now involved in mapping the regions of space that contain these huge superclusters.
What is the theory of the acceleration due to gravity?
During a fee fall, when there is no normal force to resist the force of gravity, the body's acceleration is the same as the force of gravity 9.8m/s-2