Mathematics is fundamental in all sciences and mainly in Physics, which has even had many contributions. It seems that the capacity to be applied would be the motor to be create. But this not what good mathematicians as Henry Poincarè or Hardy has said. What is the beauty in mathematics, in theoretical physics or in others which could be related subjects?
For me there are very beautiful mathematical results which sounds difficut to be applied or even against our reality, which are full of "beauty" or at least "surprise".
1.Sum of natural numbers = a negative number as - 1/12.
2. Polynomials with degree five or higher are without analytical expression of their roots.
3. Banach-Tarsky theorem
4. There cannot exit more than five regular polyhedra in three dimensions.