Tangles of string typically become knotted, from macroscopic twine down to long-chain macromolecules such as DNA. Here, we demonstrate that knotting also occurs in quantum wavefunctions, where the ...

Based on these eigenfunctions there is constructed a special system of functions that already forms the basis. However the obtained system is not already the system of the eigenfunctions of the ...

The spheres in $3-\dim$ Euclidean space are characterized by the fact that they have three 1st eigenfunctions with square sum equal to a constant. This monthly journal, begun in 1950, is devoted ...