Properties

Label 2.8.18.34
Base \(\Q_{2}\)
Degree \(8\)
e \(4\)
f \(2\)
c \(18\)
Galois group $(C_4^2 : C_2):C_2$ (as 8T26)

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Defining polynomial

\( x^{8} + 2 x^{6} + 8 x^{5} + 6 x^{4} + 28 \)

Invariants

Base field: $\Q_{2}$
Degree $d$ : $8$
Ramification exponent $e$ : $4$
Residue field degree $f$ : $2$
Discriminant exponent $c$ : $18$
Discriminant root field: $\Q_{2}(\sqrt{-1})$
Root number: $-i$
$|\Aut(K/\Q_{ 2 })|$: $2$
This field is not Galois over $\Q_{2}$.

Intermediate fields

$\Q_{2}(\sqrt{*})$, 2.4.4.3

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(14 t + 10\right) x^{2} + \left(8 t + 8\right) x + 6 t + 14 \in\Q_{2}(t)[x]$

Invariants of the Galois closure

Galois group:$D_4:D_4$ (as 8T26)
Inertia group:Intransitive group isomorphic to $C_4:D_4$
Unramified degree:$2$
Tame degree:$1$
Wild slopes:[2, 2, 3, 7/2, 7/2]
Galois mean slope:$51/16$
Galois splitting model:$x^{8} + 2 x^{6} - 2 x^{4} - 8 x^{2} - 4$