The famous number has many practical uses, mathematicians say, but is it really worth the time and effort to work out its trillions of digits? Swiss researchers have spent 108 days calculating pi to a ...

Most famous equation: Einstein's E = mc2, which means energy is equal to mass times the speed of light squared. Known digits of pi: More than 105 trillion digits Digits of pi NASA uses for equations: ...

Every year on March 14, classrooms, universities and research institutions across the world turn their attention to a subject that quietly shapes modern civilisation, mathematics. The date is observed ...