How can theory can be proven?

Answer 1

A scientific theory can never be "proven". It can only be "Disproved.

Science is a process of elimination. We eliminate those theories which are not in agreement with current experimental evidence. But, it is nearly unreasonable to claim to have produced a theory which is in perfect agreement with every scientific discovery (at least for now).

Even the most accurate scientific theories in the 21st century have uncertainties, most notably General Relativity and Quantum mechanics. These theories, for example, aim to describe the same phenomena (or equivalent mechanical phenomena) in two separate regimes. While many people hold high levels of confidence in both theories, the two have been found to be irreconcilable.

It has, in fact, been proposed that the only way this problem can be overcome is if one (or both) of these theories is modified or abandoned. But, this is only possible if one (or both) of these theories is "disproved" .

This is not necessarily a foreign thought. A lot of evidence, both experimental and observational, already seem to disagree with these theories.

Unfortunately, abandoning one theory means having to develop a new and better theory. This has proven to be a huge task, and many scientists are preferring to either reform or modify the current theories.