The Beginning of Time

10-43 Seconds: The Freezing of all Forces

The freezing that marked the very early stages of the universe do not involve particles at all but rather the unification of forces. The four fundamentals forces are Gravity, Electromagnetic, Strong, and Weak. Cosmologists calculate that the first freezing after the beginning of the universe took place at ten to the negative 43 power. (This is a really small number 0.0000000000000000000000000000000000000000001 second) Before this time there was only one strong unified force. At this point gravity split off from the strong-electroweak force so there were two fundamental forces acting in nature.

We cannot reproduce the unimaginable high temperatures that existed at this freezing point in our laboratories and we do not have successful theories that describe the unification of gravity with the other forces. Thus the earliest freezing remains both the theoretical frontier and the limit of our knowledge about the universe at the present time.

10-35 Seconds: The Freezing of the Electroweak and Strong Forces

Unified field theory that describes the behavior of all matter and forces tell us that before the universe was ten to the negative 35 power old, the strong force was unified with the Electroweak force. At this point the strong force split off from the Electroweak force. That is, before this time there were only two fundamental forces acting in the universe(the strong-electroweak force and gravity) but after this time there were three.

Two important events are associated with the freezing at this point. There are:

The Elimination of antimatter: Antimatter is very rare in the universe we live in. It was not until the twentieth century that scientists were able to identify antimatter, and we presently have compelling evidence that no large collections of antimatter exist anywhere in the universe. For example spaceships have landed on the Moon, Mars and Venus, and if any of those bodies had been made of antimatter, those spaceships would have been annihilated in a massive burst of gamma rays. As they did not, we conclude that none of those planets are made of antimatter.

By the same token, the solar wind, composed of ordinary matter, is constantly streaming outward from the Sun to the farthest reaches of the solar system. If any objects in the solar system were made of antimatter, the protons in the solar wind would be annihilating with materials in that body, and we would see evidence of it. The entire solar system, therefore, is made of ordinary matter. By the same type of argument, scientists have been able to show that our entire galaxy is made of ordinary matter, and no clusters of galaxies anywhere in the observable universe are made of antimatter.

The question, then, is this: If antimatter is indeed simply a mirror image of ordinary matter, and if antimatter appears in our theories on an equal footing with ordinary matter, as it does, then why is there so little antimatter in the universe?

Unified field theories give us an explanation of this striking feature of the cosmos. In experiments, we find one instance of a particle that decays preferentially into matter over antimatter---a particle whose decay products more often contain more matter then antimatter. This particle is called "K-zero-long, one of the many heavy particles such as protons and neutrons that were discovered in the latter part of the twentieth century.

If you take the theories that are successful in explaining this laboratory phenomenon and extrapolate them to the very early universe, you find that there were about 100,000,001 protons made for every 100,000,000 antiprotons. In the maelstrom that followed the big bang , the 100,000,000 antiprotons were annihilated by the 100,000,000 protons, leaving only a sea of intense radiation to mark their presence. From the collection of leftover protons, all the matter in the universe (including the Earth and its environs) was made. The discovery allowed physicists to explain the puzzling absence of antimatter in the universe, and in the 1980s led to a burst of interest in the evolution of the early universe.

Inflation:
According to the most widely accepted versions of the unified filed theories, the freezing at ten to the negative 35th second was accompanied by an incredibly rapid (but short lived increase in the rate of expansion of the universe. This short period of rapid expansion is called inflation, and theories that incorporate this phenomenon are called inflationary theories.

One way to think about inflation is to remember that changes in volume are often associated with changes in state. Water, for example, expands when it freezes, which explains why water pipes may burst open when the water in the freezes in very cold weather. In the same way. scientists, argue, the universe underwent a period of very rapid expansion during the period when the strong force froze out from the Electroweak. Roughly speaking, at this time the universe went from being much smaller than a single proton to being about the size of a grapefruit.

In the inflationary theory, the resolution of this problem is very simple. Before 10 to the negative 35 second, all parts of the universe was much smaller than you would have guessed based on the uniform rate of expansion. There was time to establish equilibrium before inflation over and increased the size of the universe. The temperature equilibrium, established early, was preserved through the inflationary era and is seen today in the uniform of the microwave background.