Quarks, the smallest building-blocks of matter, never appear alone in nature. They are always tightly bound inside the protons and neutrons. However, neutron stars, weighing as much as the Sun, but being just the size of a city like Frankfurt, possess a core so dense that a transition from neutron matter to quark matter may occur. Physicists refer to this process as a phase transition, a fancy term to describe a holistic change in the overall arrangement of a system’s structure, and in turn, its function.
When antimatter and matter meet, they annihilate, and the result is light and nothing else. Given equal amounts of matter and antimatter, nothing would remain once the reaction was completed. As long as we don’t know why more matter exists than antimatter, we can’t know why the building blocks of anything else exist, either. This is one of the biggest unsolved problems in physics, says Jens Oluf Andersen at the Norwegian University of Science and Technology. (more…)