Well, first, it would be so far beyond anything we can comprehend as intelligence that even asking that question is considered silly. An ant isn't asking us how we measure the acidity of the atmosphere. It would simply do it via some mechanism we can't implement or understand ourselves.
But, again with the caveats above: if we assume an AI that is infinitely more intelligent than us and capable of recursive self-improvement to where it's compute was made more powerful by factorial orders of magnitude, it could simply brute force (with a bit of derivation) everything it would need from the data currently available.
It could iteratively create trillions (or more) of simulations until it finds a model that matches all known observations.
But, again with the caveats above: if we assume an AI that is infinitely more intelligent than us and capable of recursive self-improvement to where it's compute was made more powerful by factorial orders of magnitude, it could simply brute force (with a bit of derivation) everything it would need from the data currently available.
It could iteratively create trillions (or more) of simulations until it finds a model that matches all known observations.