A ring automorphism of a ring 
is a ring isomorphism
from 
to itself. The ring automorphisms of 
form a group under function
composition, called the automorphism group of 
.
Ring Automorphism
See also
Automorphism Group, Ring Endomorphism, Ring Homomorphism, Ring IsomorphismExplore with Wolfram|Alpha
References
Dummit, D. S. and Foote, R. M. "Ring Homomorphisms and Quotient Rings." §7.3 in Abstract Algebra, 3rd ed. Hoboken, NJ: Wiley, pp. 239-250, 2004.Cite this as:
Weisstein, Eric W. "Ring Automorphism." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/RingAutomorphism.html