Field
Definition
A field is a commutative ring with these two properties.
- in .
- Every nonzero element of is a unit: for each with , there is with .
Remarks
The rings , and are fields. The ring is not a field. For a prime number , the ring is a field. Every field is an integral domain. A division ring has the same axioms without the commutativity of the multiplication.
Explanations
L1 human
A field is a number system where the four operations of arithmetic work. You can add, subtract, multiply, and divide by any number that is not zero. The rational numbers are the simplest example.
What this node needs for W2
- edge instance_of in: one example (0 of 1)
- edge not_instance_of in: one non-example that fails one clause (0 of 1)
The writing levels say how complete the text of a node is. They do not measure its truth.
What this needs
To read this node, read these 5 nodes in this order. The foundations come first, and the list ends with this node.
- no evidence level
- Group concept
- Ring definition
- Commutative ring definition
- Unit of a ring definition
- Field definition
What depends on this
71 nodes use this node, directly or through other nodes.
- Transcendental element 00SW8B91E7
- Uniqueness of finite fields of a given order 010PKCQPXP
- Existence of splitting fields 01441KDGBY
- Uniqueness of the algebraic closure 01VQ7C4FTB
- Eisenstein's criterion 02BPKD7TMD
- Intermediate field 02NBKVQFRQ
- Splitting field 02NZZ1J0FH
- Algebraically closed field 02SJG1HC32
- Galois field 04SGPNT8R9
- The rationals as the field of fractions of the integers 05K3J8J8T2
- Maximal ideals are prime 05WAF5T0GZ
- Uniqueness of splitting fields 069A3BC3EP
- The minimal polynomial divides every polynomial vanishing at the element 06K7SARZKR
- Subfield 07QY5RPFBR
- Finite field 08RTDHX1SK
- Subfields of a finite field 08YERZDM9X
- Algebraic extension 09EYMKMSB9
- Ring homomorphisms from a field are injective 09N7DZ7SDB
- Tower law 0A7KJ68XHT
- K[x]/(f) is a field iff f is irreducible 0AWMPX35CW
- Order of the Galois group of a Galois extension equals its degree 0BDJBH8B4Z
- Normal extension 0CBRFQ7DVZ
- A finite field of order q is the splitting field of x^q - x 0CDAHW576M
- Impossibility of doubling the cube 0CQ357M0QS
- Polynomial ring over a UFD is a UFD 0D6KH8Y59N
- Finite extensions are algebraic 0DFYTNZ6AM
- Galois extension 0DS2F7GK05
- A finite integral domain is a field 0EBE031B8E
- The multiplicative group of a finite field is cyclic 0EBZ3G455G
- Existence of an algebraic closure 0ETGBAK2CC
- Impossibility of trisecting the angle 0EWXPZCSZ0
- Transcendence of pi 0G0F7FGCGP
- Minimal polynomial of an algebraic element 0GK1WB9R98
- Degree of a field extension 0GS74FGFEK
- The order of a finite field is a prime power 0H5WWC8RZX
- Galois group of a polynomial 0JZY3R908H
- Fixed field 0KMJ6919WS
- Reduction modulo p test for irreducibility 0KWWEXW0RN
- The only ideals of a field are zero and the whole field 0M6G75E95E
- Adjoining a root of a polynomial 0M893X7YY7
- Field generated by adjoining elements 0MA5B744K3
- Algebraic closure 0MCXX29HWY
- Separable extension 0N019F6RE9
- Degree of a simple extension is the degree of the minimal polynomial 0N5QW9K7MH
- The minimal polynomial is irreducible 0NFEG48RDR
- Algebraic element 0NPW1DWECM
- Finite extension 0NRYPM9Y27
- Z/pZ is a field for p prime 0NV6E43P4A
- Simple extension 0P6SBR7YM2
- The constructible numbers form a field closed under square roots 0PN9WMRWT7
- The algebraic numbers form a field 0QFTETCHKB
- Gauss's lemma 0QFV5Y1Z5X
- The Galois group has order at most the degree 0QM98DNWVW
- Every element of a finite field of order q satisfies x^q = x 0QWR8WTZEW
- Wedderburn's little theorem 0RRNVX1VKA
- The degree of a constructible number is a power of two 0SSSM1D475
- Primitive element theorem 0SVX98HYV1
- Fundamental theorem of Galois theory 0T1Q8D0FW8
- Existence of finite fields of every prime power order 0T8M3YC5RG
- An algebraic extension of an algebraic extension is algebraic 0TPWS0K1BC
- Field of fractions 0VF11ZTTMD
- Every polynomial has a root in some extension field 0VG02M1FEZ
- Frobenius automorphism of a finite field 0VP4TBVJ19
- Prime subfield 0VPFBAY7MW
- R/M is a field iff M is maximal 0WD3SE7S1X
- Field extension 0WQ1A8SHTZ
- Impossibility of squaring the circle 0X7CVDE3BG
- Galois group 0XVR72M51M
- Gauss–Wantzel theorem 0Y34JMJNE9
- Primitive element of a finite field 0YAA9CJQXF
- K(a) is isomorphic to K[x] modulo the minimal polynomial 0ZN39QDTP9
Sources
What links here
Used by
- Algebraically closed field 02SJG1HC32
- Subfield 07QY5RPFBR
- Finite field 08RTDHX1SK
- Ring homomorphisms from a field are injective 09N7DZ7SDB
- A finite integral domain is a field 0EBE031B8E
- The only ideals of a field are zero and the whole field 0M6G75E95E
- Z/pZ is a field for p prime 0NV6E43P4A
- Wedderburn's little theorem 0RRNVX1VKA
- Field of fractions 0VF11ZTTMD
- Prime subfield 0VPFBAY7MW
- R/M is a field iff M is maximal 0WD3SE7S1X
- Field extension 0WQ1A8SHTZ