Our science isn't right. The two sets of equations we use today are typically those of relativity for the very large, and those of quantum mechanics for the very small. There is no reason why we should have a set of laws for the large-scale and a set of laws for the small-scale: both can't be right. So, no, our science is not "law."

On the other hand, we're not on the wrong track, either. Science is evolving, but evolving in the right direction. So, while the science they have 200 years from now will be that much more refined, it will still be based on the building blocks that past sciences used to understand the universe.

With regard to future societies thinking us ignorant, I doubt it again. We don't think of the ideas of past sciences as ignorant, just incorrect. Their technology only allowed them to progress so far. For example, a thousand years ago it would have been impossible to detect the small changes (at least on a day to day scale) that today we take for granted when exploring relativity. It was impossible for them to use particle accelerators to detect atoms, etc. Similarly, I think today science is used to the best of its current abilities, and one thousand years from now, if we haven't killed each other off yet, the discoveries they will have made will far surpass ours, but we are incapable of creating the kind of technology needed to make such discoveries.

Where would you plug in a TV in the Roman era, in an attempt to prove that waves exist?