Every particle has its own anti-particle. When they combine energy get release. If universe started with energy or particle+anti-particle then it should consist equal number of particle and anti-particle. But all the Matter which we see around us made of particles, why not anti-matter made of anti-particle ? why there is asymmetry in the universe ?
This topic hasn’t been resolved yet in the realm of physics..
There are various theories that try to solve the issue such as inflation and Baryogenesis theory, but none has been proven.
You could make that the topic of your PhD thesis. Would get you a Nobel if you figure it out.
Oh I didn’t know that. Thanks for the update.