The explicit understanding and definition of these rules and laws are the result of the
long-term efforts of physicists to understand what keeps atoms and the universe
together. Incessantly making models and proving these models in bigger and bigger
experiments leads to a quite sound but necessarily open set of theories and explanations
for observed phenomena. Chemists increasingly learned how atoms can react and interact
with each other, so that they are now able to use computational simulations based on
physically based theories to model, calculate, predict and prove theories and
observations.