Properties

Label 2.1.8.18a1.2
Base \(\Q_{2}\)
Degree \(8\)
e \(8\)
f \(1\)
c \(18\)
Galois group $C_2^3:(C_7: C_3)$ (as 8T36)

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Defining polynomial

\(x^{8} + 4 x^{4} + 4 x^{3} + 2\) Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $8$
Ramification index $e$: $8$
Residue field degree $f$: $1$
Discriminant exponent $c$: $18$
Discriminant root field: $\Q_{2}$
Root number: $1$
$\Aut(K/\Q_{2})$: $C_1$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:$[\frac{18}{7}, \frac{18}{7}, \frac{18}{7}]$
Visible Swan slopes:$[\frac{11}{7},\frac{11}{7},\frac{11}{7}]$
Means:$\langle\frac{11}{14}, \frac{33}{28}, \frac{11}{8}\rangle$
Rams:$(\frac{11}{7}, \frac{11}{7}, \frac{11}{7})$
Jump set:$[1, 3, 7, 15]$
Roots of unity:$2$

Intermediate fields

The extension is primitive: there are no intermediate fields between this field and $\Q_{ 2 }$.

Canonical tower

Unramified subfield:$\Q_{2}$
Relative Eisenstein polynomial: \( x^{8} + 4 x^{4} + 4 x^{3} + 2 \) Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z + 1$
Associated inertia:$1$
Indices of inseparability:$[11, 11, 8, 0]$

Invariants of the Galois closure

Galois degree: $168$
Galois group: $F_8:C_3$ (as 8T36)
Inertia group: $F_8$ (as 8T25)
Wild inertia group: $C_2^3$
Galois unramified degree: $3$
Galois tame degree: $7$
Galois Artin slopes: $[\frac{18}{7}, \frac{18}{7}, \frac{18}{7}]$
Galois Swan slopes: $[\frac{11}{7},\frac{11}{7},\frac{11}{7}]$
Galois mean slope: $2.357142857142857$
Galois splitting model:$x^{8} - 28 x^{6} - 28 x^{5} + 196 x^{4} + 308 x^{3} - 224 x^{2} - 528 x - 182$