Supporting evidence in the harder sciences (physics, chemistry, etc.) is much closer to the mathematical standard than the softer sciences like biology. There is even less of a standard in the historical sciences like geology, archeology, and paleontology. It is far easier to admit situations on which science is not clear in the hard sciences than the softer and historical sciences.
Not really - any fool can come up with a series of equations. The trick is showing that these equations actually mean something in the physical world. Take string theory for example. No one is disputing the mathematical correctness of it. It's just that no one has been able to find any way of generating testable predictions from it.