At long last, a unified theory combining gravity with the other fundamental forces—electromagnetism and the strong and weak nuclear forces—is within reach. Bringing gravity into the fold has been the goal of generations of physicists, who have struggled to reconcile the incompatibility of two cornerstones of modern physics: quantum field theory and Einstein's theory of gravity.
That’s the “make predictions” part, smartass. There is a big difference between calculating the limits with a theory and inventing new limits and trying to find maths that fit.
And even then is the experimental evidence still the most important part. Wormholes, warp drives and white holes are also mathematically possible. Doesn’t mean they are real. We didn’t call the higgs field real until it was experimentally proven.
Yes, people found a whole lot out via maths. But they didn’t just have some idea about how they think nature works and then invented some formulas for that. They built on prior theories and evidence.