No, electrons and positrons do not come from quarks. Quarks are fundamental particles that are found inside protons and neutrons, which are collectively known as hadrons. Electrons and positrons, on the other hand, are elementary particles called leptons. They belong to a different category of particles than quarks.
Electrons and positrons are not composed of anything smaller and are considered to be fundamental particles, meaning they are not made up of smaller particles. They are thought to be elementary and indivisible.
In the early stages of the universe, during the Big Bang, vast amounts of energy were present. As the universe cooled and expanded, this energy began to condense into various particles, including electrons and positrons. The exact mechanisms of particle creation in the early universe are still the subject of ongoing research and exploration in the field of particle physics.
It's important to note that electrons and positrons continue to be created and annihilated in various physical processes even today. For example, high-energy collisions in particle accelerators can produce electron-positron pairs. Additionally, in certain radioactive decays, such as beta decay, an electron or a positron can be emitted.
Overall, electrons and positrons are not derived from quarks. They are distinct particles with unique properties and origins.