Why Does Early Universe Have Low Entropy?

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In summary, entropy, which is closely related to randomness, is a natural process that occurs in our everyday experience. It is also considered a physical law of thermodynamics. However, the early universe had such low entropy despite the expectation that everything exploding from a single point would lead to a highly random distribution of matter and energy. This is due to the unique nature of the "big bang" as an explosion of space, rather than in space, and the lack of communication between points during the early expansion.
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mrspeedybob
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Entropy has been defined as nearly synonamous with randomness (http://www.google.com/search?hl=en&...&sa=X&ei=PyWxTPLOFcT6lwf-rZmYDQ&ved=0CBIQkAE"). In our every-day experience things naturaly progress from a state of less entropy to a state of more entropy. This observation has even been elevated to the status of a physical law of thermodynamics. My question is why did the early universe have such low entropy? It seems like everything exploding from a single point would lead to a highly random distribution of mater and energy.
 
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Hello. This is my first post in these forums. I have no education in physics and little in mathematics beyond the basics. So, definitely take what I have to say as the opinion of the curious only. Looking forward to some real answers later. :)

One thing to keep in mind is that the "big bang" was not like a typical explosion. In any explosion we are familiar with, it occurs in space, while the "big bang" was an explosion of space. So, there is no central, single point of energy. The central point is every point in the ever expanding space.

Also, it seems to me that during the first phases of this expansion each point had no time with which to communicate with any other point. Even when gravity split and became a distinct force, the very small clumps of matter that were present did not have time to attract or act upon the matter surrounding them.
 

1. What is entropy in the context of the early universe?

Entropy is a measure of the disorder or randomness of a system. In the context of the early universe, it refers to the amount of disorder or randomness present in the universe at that time.

2. Why is it important that the early universe had low entropy?

The low entropy state of the early universe is important because it allows for the formation of complex structures, such as galaxies and stars, which are essential for the existence of life. If the early universe had high entropy, it would have been too chaotic for these structures to form.

3. How did the early universe have low entropy?

The low entropy state of the early universe is believed to have been a result of the initial conditions of the universe. At the beginning of the universe, it is thought that all matter and energy were concentrated in a single point, known as the singularity. As the universe expanded and cooled, it became less chaotic and more ordered, resulting in low entropy.

4. Can entropy increase over time in the universe?

Yes, according to the second law of thermodynamics, the overall entropy of the universe will always increase over time. However, this does not mean that certain regions of the universe cannot have low entropy, as long as the overall trend is towards increasing entropy.

5. How does the low entropy of the early universe relate to the arrow of time?

The low entropy state of the early universe is closely related to the concept of the arrow of time, which refers to the direction in which time flows. The low entropy state of the early universe is considered to be the "starting point" of the arrow of time, as from that point, the universe has been increasing in entropy. This is also known as the "past hypothesis."

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