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## G\"odel algebras

Abbreviation: G\”odA

### Definition

A G\”odel algebra is a Heyting algebras $\mathbf{A}=\langle A,\vee,0,\wedge,1,\rightarrow\rangle$ such that

$(x\to y)\vee(y\to x)=1$

Remark: G\”odel algebras are also called linear Heyting algebras since subdirectly irreducible G\”odel algebras are linearly ordered Heyting algebras.

### Definition

A G\”odel algebra is a representable FLew-algebra $\mathbf{A}=\langle A, \vee, 0, \wedge, 1, \cdot, \rightarrow\rangle$ such that

$x\wedge y=x\cdot y$

##### Morphisms

Let $\mathbf{A}$ and $\mathbf{B}$ be G\”odel algebras. A morphism from $\mathbf{A}$ to $\mathbf{B}$ is a function $h:A\rightarrow B$ that is a homomorphism:

$h(x\vee y)=h(x)\vee h(y)$, $h(0)=0$, $h(x\wedge y)=h(x)\wedge h(y)$, $h(1)=1$, $h(x\rightarrow y)=h(x)\rightarrow h(y)$

Example 1:

### Properties

Classtype variety decidable decidable countable yes yes yes, $n=2$ yes, $e=1$ yes yes yes

### Finite members

$\begin{array}{lr} f(1)= &1\\ f(2)= &1\\ f(3)= &1\\ f(4)= &\\ f(5)= &\\ f(6)= &\\ f(7)= &\\ f(8)= &\\ f(9)= &\\ f(10)= &\\ \end{array}$