Following the annihilation of matter and antimatter, a nano-asymmetry of matter remains to the present day. Most of the hadrons and anti-hadrons were eliminated in annihilation reactions, leaving a small residue of hadrons. Upon elimination of anti-hadrons, the Universe was dominated by photons, neutrinos and electron-positron pairs.
The aftermath of the annihilation of matter and antimatter still exists today, with most hadrons and their antiparticles being eliminated in reactions, leaving behind a small amount. The Universe then became predominantly composed of photons, neutrinos, and electron-positron pairs.