2-element Boolean algebra
Name: B2=⟨{0,1},∨,0,∧,1,′⟩
Elements: 0,1
Constant operations
0=0
1=1
Unary operations
Complement = negation = 1−x =
x | 0 | 1 |
---|---|---|
x′ | 1 | 0 |
Alternative notation: −x=¯x=x−=¬x
Binary operations
Join = or = truncated addition = min{x+y,1} =
∨ | 0 | 1 |
---|---|---|
0 | 0 | 1 |
1 | 1 | 1 |
Meet = and = multiplication =
∧ | 0 | 1 |
---|---|---|
0 | 0 | 0 |
1 | 0 | 1 |
Derived operations
Symmetric difference: x⊕y=(x∨y)∧(x∧y)′ = (x∧y′)∨(y∧x′)
⊕ | 0 | 1 |
---|---|---|
0 | 0 | 1 |
1 | 1 | 0 |
Implication: x→y=x′∨y
→ | 0 | 1 |
---|---|---|
0 | 1 | 1 |
1 | 0 | 1 |
Bi-implication: x↔y=(x→y)∧(y→x)
↔ | 0 | 1 |
---|---|---|
0 | 1 | 0 |
1 | 0 | 1 |
Nand: x|y=(x∧y)′
| | 0 | 1 |
---|---|---|
0 | 1 | 1 |
1 | 1 | 0 |
Nor: x↓y=(x∨y)′
↓ | 0 | 1 |
---|---|---|
0 | 1 | 0 |
1 | 0 | 0 |
Properties
Simple | Yes |
---|---|
Subdirectly irreducible | Yes |
Basic results
This algebra generates the variety of all Boolean algebras.
Every Boolean algebra is a subdirect product of B2.
Maximal subalgebras
none
Minimal superalgebras
Maximal homomorphic images
Minimal homomorphic preimages
Maximal subvarieties
Minimal supervarieties
???