The methods of theoretical physics should be applicable to all those branches of thought in which the essential features are expressible with numbers.
I do not see how a man can work on the frontiers of physics and write poetry at the same time. They are in opposition.
Pick a flower on Earth and you move the farthest star.
In science one tries to tell people, in such a way as to be understood by everyone, something that no one ever knew before. But in poetry, it's the exact opposite.
The fundamental laws necessary for the mathematical treatment of a large part of physics and the whole of chemistry are thus completely known, and the difficulty lies only in the fact that application of these laws leads to equations that are too complex to be solved.
It seems that if one is working from the point of view of getting beauty in one's equations, and if one has really a sound insight, one is on a sure line of progress.