In the 1800s mathematicians introduced a formal theory of symmetry group theory Now a branch of abstract algebra this subject first arose in the theory of equations Symmetry is an immensely important concept in mathematics & throughout the sciences & its applications range across the entire subject Symmetry governs the structure of crystals innumerable types of pattern formation how systems change their state as parameters vary; & fundamental physics is governed by symmetries in the laws of nature It is highly visual with applications that include animal markings locomotion evolutionary biology elastic buckling waves the shape of the Earth & the form of galaxies In this Very Short Introduction Ian Stewart demonstrates its deep implications & shows how it plays a major role in the current search to unify relativity & quantum theory ABOUT THE SERIES The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area These pocket-sized books are the perfect way to get ahead in a new subject quickly Our expert authors combine facts analysis perspective new ideas & enthusiasm to make interesting & challenging topics highly readable