You likely refer to mass-energy equivalence, observations that mass can be converted into energy and vice versa led to series of discoveries that described principles of how this interaction happens. Einstein was the one who first described it mathematically.
Note that 100-120 years ago scientific thought was far less influenced by USA. Europe was in the lead. Germany, England, France.
Why shouldn’t it hold universally? The principle is sound from common sense and in a way it was analyzed, described and studied holds at a finest levels of particles.
It’s important to avoid conflating experiences of individual that are measured by means of body, that are very rough and finite from what actually can and can’t be measured and understood. Humans exist in a very small, relatively cool, not quite varying volume, from the standpoint of universe, even Earth itself is far less explored that people might think. Projecting experiences from the environment where they happened is a way to create illusions.
Genetics was discovered initially as just laws or rules how features are inherited without any concept of genes, yet this didn’t stop it from being valid, genes predicted and then discovered, although they were thought to be only imaginary explanation by many or at least something that can’t be detected.
Mathematics routinely studies objects that even if they exist somehow wouldn’t be perceivable by human cognition, yet their properties are understood, analysed and known.
