Newtonian physics was good at describing interactions we can observe. But one of the events that pushed physics to new possibilities was Einstein's work for a unified field theory. I love how he set it all up:
Strong and Weak Nuclear forces
When you think about the phenomena listed above we experience each of them as different and distinct from each other.
But Einstein had a brilliant idea, what if our senses are lying to us? What if the forces listed above only appear different to us because the conditions that form the present day universe have changed since its creation?
Turn the great cosmic clock back to a few seconds after the big bang, and all the fundamental forces of physics reveal themselves as a single "unified" force of an expanding universe.
From quantum mechanics to string theory, science had to also expand because Einstein's work exposed the limits of classical physics. We are entering relms where reality itself is now in question.