Properties

Label 2.8.18.56
Base \(\Q_{2}\)
Degree \(8\)
e \(8\)
f \(1\)
c \(18\)
Galois group $D_4\times C_2$ (as 8T9)

Related objects

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Defining polynomial

\( x^{8} + 168 x^{4} + 912 \)

Invariants

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

Intermediate fields

$\Q_{2}(\sqrt{-*})$, $\Q_{2}(\sqrt{-2*})$, $\Q_{2}(\sqrt{2})$, 2.4.6.9, 2.4.8.3, 2.4.8.5

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

Unramified/totally ramified tower

Unramified subfield:$\Q_{2}$
Relative Eisenstein polynomial:\( x^{8} + 16 x^{7} + 358 x^{6} + 2920 x^{5} + 4048 x^{4} - 7676 x^{3} + 170080 x^{2} - 258776 x + 561838 \)

Invariants of the Galois closure

Galois group:$C_2\times D_4$ (as 8T9)
Inertia group:$C_2^3$
Unramified degree:$2$
Tame degree:$1$
Wild slopes:[2, 2, 3]
Galois mean slope:$9/4$
Galois splitting model:$x^{8} - 4 x^{7} + 2 x^{6} + 8 x^{5} - 8 x^{4} + 4 x^{3} - 16 x^{2} + 16 x - 2$