Mathematical problems in classical physics

Mathematics is the name for those domains of theoretical physics that are temporarily unfashionable. The advantage of being unfashionable is that it presents the possibility of the rigorous and deep investigation of well-established mathematical models. A sleeping “physical theory” can be formulated as a chain of statements having exact mathematical meaning of mathematical conjectures. Such conjectures can then be proved or disproved. In many cases the mathematical problems arising this way are very difficult, and progress is rather slow. It is much easier to obtain a new result in an unexplored domain. Hence, most researchers carefully avoid any thinking on the old classical problems.