So, unless something was created before by a superior being, either the universe or the big bang happened, and I think that the universe DOES exist. It's not conservation of mass, its conservation of energy. When the big bang formed, particles didn't exist because the energy was too concentrated to allow particles to be formed. Some more examples are nuclear reactions, they don't have the same atoms from one reaction to another, however their overall energy is conserved. Two things wrong: 1.In order for there to be energy, there must be atoms. (definition by msn) In order for there to be effort, there must be something making the effort. According to what you said, there was energy before atoms. 2. The law of conservation of mass applies to ALL CHEMICAL REACTIONS. The big bang theory states that there was a biproduct of dust after the explosion which is proof that the theory involves a chemical reaction.