80-year-old enigma

摘要

Would a basketball spinning on a fingertip behave the same way in an infinite number of dimensions? The question has flummoxed mathematicians for 80 years, but now it looks as if the answer is yes - a find that could have implications for quantum theory. The invariant subspace problem was studied in the 1930s by John von Neumann, a pioneer of operator theory, the mathematics behind "quantum mechanics.