When other galaxies in the universes are examined we can see that their light rays are reaching us stretched out, at lower frequencies. Scientists observed that light rays were being stretched out, so they concluded that the universe was expanding. This is similar to how a speeding car passes you and gets quieter the further away it gets. If the universe were not expanding, gravity would have drawn everything in the universe together and there would be no more planets, or stars, only pressure, and heat, and elements in a very dense, very small object. One day, the energy that drives our universe to constantly expand will succumb to the awesome power of gravity, and everything will slowly start to contract. What gave the universe the energy to expand so rapidly? The big bang.
The theory is that everything in the universe started out in an infinitely dense, infinitely hot mass that was approximately the size of a pebble. What was there besides this pebble sized mass? This is where God comes into the picture for many scientists. To our best knowledge of science we cannot definitively know what there was before the pebble exploded. In a trillion trillionth of a second, the pebble had expanded to astronomical proportions the likes of which are practically unfathomable. The image crudely shows how the universe all started out in the small white hot space, then expanded. Galaxies formed, and the galaxies spread out. Galaxies did not just pop out of this epic explosion, they took billions of years to form.
(Image from http://scienceblogs.com/startswithabang/upload/2010/01/q_a_did_inflation_happen_befor/big-bang-8.jpg)
Several hundred million years after the big bang, as the universe began to cool down. There were no planets, no light, only vast clouds of gas like the ones below.
The universe was a dark expanding place filled with gas. The gas was all spread out throughout the universe but thanks to random imperfections, there were some places where gas clouds were denser than others. This allowed gravity to slowly pull gases closer and closer until they became dense, and hot. And God said, “Let there be light”! The gases got so hot at the core that hydrogen atoms began to fuse to make helium which released a great amount of energy and light. The universe was lighting up, gas clouds everywhere were beginning to turn into stars. The reason the gas clouds could form into stars was because of the imperfections in the assortment of gases.
In the picture above all of the white dots are the same distances away from each other, they are organized. Let’s say the gases after the big bang were uniformly distributed among the universe like the dots in the picture. Gravity would not affect their location because each dot, or hydrogen atom, would be pulled equally by the gravity of those around it. Massive gas clouds would not form or condense and there would be no stars.
This is more like what the gases looked like in the early universe. They are random, and some are closer than others. Look, for example, at the upper left corner of dots. There are more up there than, right in the middle. This disorganized arrangement allowed some parts, like the upper left, to have more mass than other parts, like the middle. The gases got closer and closer even drew others closer into hot, huge, and dense masses that would later become stars.
Why did the imperfections happen? Why did the big bang happen? What was there before the big bang? With questions like these that we cannot answer yet, many give the simple answer that God did it. Although scientists might be able to make new theories to answer the age old questions or disprove our current theories, it will be a long time before we have enough evidence to prove or disprove God’s reality.