Properties

Label 2.2.8.40c1.20
Base \(\Q_{2}\)
Degree \(16\)
e \(8\)
f \(2\)
c \(40\)
Galois group $A_4:C_4$ (as 16T62)

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Defining polynomial

$( x^{2} + x + 1 )^{8} + 4 ( x^{2} + x + 1 )^{7} + 4 ( x^{2} + x + 1 )^{5} + 4 ( x^{2} + x + 1 )^{4} + 4 ( x^{2} + x + 1 )^{2} + 8 x + 2$ Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $16$
Ramification index $e$: $8$
Residue field degree $f$: $2$
Discriminant exponent $c$: $40$
Discriminant root field: $\Q_{2}$
Root number: $1$
$\Aut(K/\Q_{2})$: $C_4$
This field is not Galois over $\Q_{2}.$
Visible Artin slopes:$[\frac{8}{3}, \frac{8}{3}, 3]$
Visible Swan slopes:$[\frac{5}{3},\frac{5}{3},2]$
Means:$\langle\frac{5}{6}, \frac{5}{4}, \frac{13}{8}\rangle$
Rams:$(\frac{5}{3}, \frac{5}{3}, 3)$
Jump set:$[1, 3, 7, 15]$
Roots of unity:$6 = (2^{ 2 } - 1) \cdot 2$

Intermediate fields

$\Q_{2}(\sqrt{5})$, 2.2.2.6a1.2, 2.1.4.8a1.1, 2.2.4.16a1.1

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

Canonical tower

Unramified subfield:$\Q_{2}(\sqrt{5})$ $\cong \Q_{2}(t)$ where $t$ is a root of \( x^{2} + x + 1 \) Copy content Toggle raw display
Relative Eisenstein polynomial: \( x^{8} + 4 x^{7} + 4 x^{5} + 4 x^{4} + 4 x^{2} + 8 t + 2 \) $\ \in\Q_{2}(t)[x]$ Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z^2 + 1$,$z + 1$
Associated inertia:$1$,$1$
Indices of inseparability:$[13, 10, 8, 0]$

Invariants of the Galois closure

Galois degree: $48$
Galois group: $A_4:C_4$ (as 16T62)
Inertia group: Intransitive group isomorphic to $C_2\times A_4$
Wild inertia group: $C_2^3$
Galois unramified degree: $2$
Galois tame degree: $3$
Galois Artin slopes: $[\frac{8}{3}, \frac{8}{3}, 3]$
Galois Swan slopes: $[\frac{5}{3},\frac{5}{3},2]$
Galois mean slope: $2.5833333333333335$
Galois splitting model: $x^{16} - 8 x^{15} - 144 x^{14} + 684 x^{13} + 8534 x^{12} - 15540 x^{11} - 224124 x^{10} + 59028 x^{9} + 2683719 x^{8} + 936932 x^{7} - 15745228 x^{6} - 8166244 x^{5} + 45008826 x^{4} + 20359996 x^{3} - 55917608 x^{2} - 15263136 x + 19992411$ Copy content Toggle raw display