Properties

Label 2.16.48.1
Base \(\Q_{2}\)
Degree \(16\)
e \(8\)
f \(2\)
c \(48\)
Galois group $C_4\times C_2^2$ (as 16T2)

Related objects

Downloads

Learn more

Defining polynomial

\(x^{16} - 8 x^{15} + 64 x^{14} + 8 x^{13} + 76 x^{12} + 48 x^{11} + 64 x^{10} + 256 x^{9} + 56 x^{8} + 144 x^{7} + 160 x^{6} + 432 x^{5} + 456 x^{4} + 256 x^{2} + 288 x + 516\) Copy content Toggle raw display

Invariants

Base field: $\Q_{2}$
Degree $d$: $16$
Ramification exponent $e$: $8$
Residue field degree $f$: $2$
Discriminant exponent $c$: $48$
Discriminant root field: $\Q_{2}$
Root number: $1$
$\card{ \Gal(K/\Q_{ 2 }) }$: $16$
This field is Galois and abelian over $\Q_{2}.$
Visible slopes:$[2, 3, 4]$

Intermediate fields

$\Q_{2}(\sqrt{-5})$, $\Q_{2}(\sqrt{5})$, $\Q_{2}(\sqrt{-2})$, $\Q_{2}(\sqrt{-1})$, $\Q_{2}(\sqrt{2\cdot 5})$, $\Q_{2}(\sqrt{-2\cdot 5})$, $\Q_{2}(\sqrt{2})$, 2.4.8.2, 2.4.11.1, 2.4.6.1, 2.4.6.2, 2.4.4.1, 2.4.8.4, 2.4.8.1, 2.4.8.3, 2.4.11.2, 2.4.11.3, 2.4.11.4, 2.8.24.5, 2.8.16.6, 2.8.22.7, 2.8.22.2, 2.8.24.7, 2.8.24.10, 2.8.24.9

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

Unramified/totally ramified tower

Unramified subfield:$\Q_{2}(\sqrt{5})$ $\cong \Q_{2}(t)$ where $t$ is a root of \( x^{2} + x + 1 \) Copy content Toggle raw display
Relative Eisenstein polynomial: \( x^{8} + 8 t x^{7} + \left(8 t + 8\right) x^{5} + \left(8 t + 10\right) x^{4} + \left(8 t + 4\right) x^{2} + 8 x + 16 t + 26 \) $\ \in\Q_{2}(t)[x]$ Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z + 1$,$z^{2} + 1$,$z^{4} + 1$
Associated inertia:$1$,$1$,$1$
Indices of inseparability:$[17, 10, 4, 0]$

Invariants of the Galois closure

Galois group:$C_2^2\times C_4$ (as 16T2)
Inertia group:Intransitive group isomorphic to $C_2\times C_4$
Wild inertia group:$C_2\times C_4$
Unramified degree:$2$
Tame degree:$1$
Wild slopes:$[2, 3, 4]$
Galois mean slope:$3$
Galois splitting model:$x^{16} - x^{8} + 1$