Prime ideal
In theory, the ring is a prime ideal is a subset of a ring, similar to acts as a prime number as the element of the whole numbers.
Definitions
It was a ring. Then is called a two-sided ideal prime ideal or prime, if is real, so, and if for all ideals:
Also, is called complete prime ideal or vollprim if is real and if for all:
Equivalent definitions
- A two-sided ideal if and only prime, if it is genuine and if for all:
- A two-sided ideal if and only vollprim, if it is genuine and if the factor ring is zero divisors.
Spectrum
The set of all (real) prime ideals of a ring is called spectrum and with Spec ( ) listed.
Properties
- Each fully- prime ideal is prime, but not vice versa. For example, the zero ideal in the ring of real matrices prim, but not vollprim.
- In commutative rings are prim and vollprim equivalent.
In commutative rings with identity holds:
- An element is a prime element if and only if it is generated by principal ideal is a prime ideal.
- An ideal is prime if and only if the factor ring is an integral domain.
- Contains a prime ideal an average of a finite number of ideals, it also contains one of the ideals.
- An ideal is a prime ideal if and only if the complementary set is complete multiplicative. This leads to the concept of localization, which is meant the ring that you as writes.
Examples
- The set of even integers being a prime ideal in the ring of integers as a product of two integers is just only if at least one factor is straight.
- The set of integers divisible by 6 is not a prime ideal, since 2.3 = 6 is in the subset, but neither 2 nor 3
- In the ring, the maximal ideal is not a prime ideal.
- A maximal ideal of a ring if and only prime if. In particular, is prime if a unit element contains.
- The zero ideal in a commutative ring is a prime ideal if and only if an integral domain is.
- In a non- commutative ring this equivalence does not hold, such as the example of the n × n- matrices is for n> 1.
- In general, the inverse image of a prime ideal is a prime ideal under a ring homomorphism