Irish physicist, astronomer, and mathematician Sir William Rowan Hamilton introduced quaternions, a non-commutative extension of complex numbers, on October 16, 1843. Benjamin Olinde Rodrigues had ...

Imagine winding the hour hand of a clock back from 3 o’clock to noon. Mathematicians have long known how to describe this rotation as a simple multiplication: A number representing the initial ...

HAVING a vivid recollection of the pleasure I derived born Prof. Gibbs's attacks upon the quaternionic system in the rather one-sided discussion that took place about two years ago in this journal, I ...

WE are unable to read this treatise, because it is printed in Japanese. The mathematical formulæ and woodcuts show that the author is introducing his students to those elementary geometrical (curve ...