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Name:  Claire E.
Status: student
Age: 17
Location: N/A
Country: N/A
Date: 2000-2001

As the universe cools, hadrons form from quarks, nuclei form from hadrons and finally atoms form from nuclei. How does this happen?


Temperature is the avarage amount of random energy per individual object. It relates to how fast objects are bouncing around, smashing into each other. When the universe is very hot, the quarks are jumping around at very fast speeds. When they bang into each other, they bounce apart. Imagine a ping-pong ball with double-sided tape on it. If you throw it very hard against a wall, it will bounce back. If you throw it lightly at a wall, it will stick. As the universe cools, the quarks slow down. Eventually they move slowly enough to hold onto each other. This results in hadrons, such as protons and neutrons. Protons and neutrons don't hold eachother as strongly as individual quarks do. It has to get even cooler, with particles having less energy, for protons and neutrons to grab onto each other. Then you have nuclei. The individual electrons, however, are still moving around. When things get even cooler, the atoms can hold onto the electrons. Then you have complete atoms.

Dr. Ken Mellendorf
Illinois Central College

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