Properties

Label 2.8.22.17
Base \(\Q_{2}\)
Degree \(8\)
e \(4\)
f \(2\)
c \(22\)
Galois group $Q_8:C_2$ (as 8T11)

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Defining polynomial

\( x^{8} + 2 x^{4} + 16 x^{3} + 16 x + 4 \)

Invariants

Base field: $\Q_{2}$
Degree $d$ : $8$
Ramification exponent $e$ : $4$
Residue field degree $f$ : $2$
Discriminant exponent $c$ : $22$
Discriminant root field: $\Q_{2}$
Root number: $1$
$|\Aut(K/\Q_{ 2 })|$: $4$
This field is not Galois over $\Q_{2}$.

Intermediate fields

$\Q_{2}(\sqrt{*})$, $\Q_{2}(\sqrt{2})$, $\Q_{2}(\sqrt{2*})$, 2.4.6.1

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

Unramified/totally ramified tower

Unramified subfield:$\Q_{2}(\sqrt{*})$ $\cong \Q_{2}(t)$ where $t$ is a root of \( x^{2} - x + 1 \)
Relative Eisenstein polynomial:$ x^{4} + \left(16 t + 24\right) x^{3} + \left(16 t + 24\right) x + 30 t + 2 \in\Q_{2}(t)[x]$

Invariants of the Galois closure

Galois group:$D_4:C_2$ (as 8T11)
Inertia group:Intransitive group isomorphic to $C_2\times C_4$
Unramified degree:$2$
Tame degree:$1$
Wild slopes:[2, 3, 4]
Galois mean slope:$3$
Galois splitting model:$x^{8} - 12 x^{6} + 54 x^{4} - 72 x^{2} + 36$