Differential ring: Difference between revisions
Jump to navigation
Jump to search
imported>Richard Pinch (new entry, just a stub) |
imported>Richard Pinch m (→Examples: typo) |
||
Line 8: | Line 8: | ||
==Examples== | ==Examples== | ||
* Every ring is a differential ring with the zero map as derivation. | * Every ring is a differential ring with the zero map as derivation. | ||
* The [[formal derivative]] makes the polynomial ring ''R''[''X'' | * The [[formal derivative]] makes the polynomial ring ''R''[''X''] over ''R'' a differential ring with | ||
:<math>D(X^n) = n.X^{n-1} ;\,</math> | :<math>D(X^n) = n.X^{n-1} ;\,</math> | ||
:<math>D(r) = 0 \mbox{ for } r \in R.\,</math> | :<math>D(r) = 0 \mbox{ for } r \in R.\,</math> |
Revision as of 16:41, 20 December 2008
In ring theory, a differential ring is a ring with added structure which generalises the concept of derivative.
Formally, a differential ring is a ring R with an operation D on R which is a derivation:
Examples
- Every ring is a differential ring with the zero map as derivation.
- The formal derivative makes the polynomial ring R[X] over R a differential ring with
Ideals
A differential ring homomorphism is a ring homomorphism f from differential ring (R,D) to (S,d) such that f.D = d.f. A differential ideal is an ideal I of R such that D(I) is contained in I.
References
- Andy R. Magid (1994). Lectures on Differential Galois Theory. AMS Bookstore, 1-2. ISBN 0-8218-7004-1.
- Bruno Poizat (2000). Model Theory. Springer Verlag, 71. ISBN 0-387-98655-3.