The Yin-Yang symbol - symmetry requires an eye to see.
During the first trillionth of a second, when the strong force is departing from the unified forces, matter and energy played a spectacular show. True elementary particles, the constituents of every matter in the universe, spawned out of existence thanks to Einstein’s famous E=mc2. At that time, the universe is flooded with particles called quarks and leptons (Electron is an example of lepton) and also their antimatter counterpart. Bosons are present too to account for the particles interaction. In this quark-lepton era, the universe is still so dense that the distance between quarks that are fused together and those who are not are almost undistinguishable.
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Here is one of the interesting parts of the cosmic evolution: For every bits of matter created in the first sliver of time, an antimatter (sort of like a counterpart of matter) is created too. Antimatter behaves exactly like a matter particle except it has different charge. For example, electron is matter particle; the antimatter counter part of electron is a positron. As the name suggest, the positron has exactly the same properties of electron but it carries an opposite charge. An electron is negatively charged and a positron is well, positively charged. If both electron and positron meet, they will collide and vanish in existence and create a pair of photons which are particles of light with the energy content exactly the same as the electron and positron combined. A process physicist called annihilation.
The magic of creation is that somewhere during the forces split; there exist an asymmetry of the particle pairs created. For every billion anti-quarks created, there is a billion and one quark. But that small difference is hardly noticeable amongst the continuous creation, annihilation and re-creation of fundamental particles of nature because the energy involved at the early universe is still highly intense. But eventually, the extra one quark (and other un-annihilated particles) managed to survive as the universe now continues to expand and cool. The universe is now the size of our solar system with temperature about a trillion degrees. It has been a millionth of second since the beginning of time.