Defining polynomial
$( x^{4} + 3 x^{2} + 12 x + 2 )^{2} + 13$
|
Invariants
Base field: | $\Q_{13}$ |
Degree $d$: | $8$ |
Ramification index $e$: | $2$ |
Residue field degree $f$: | $4$ |
Discriminant exponent $c$: | $4$ |
Discriminant root field: | $\Q_{13}$ |
Root number: | $-1$ |
$\Aut(K/\Q_{13})$ $=$$\Gal(K/\Q_{13})$: | $C_2\times C_4$ |
This field is Galois and abelian over $\Q_{13}.$ | |
Visible Artin slopes: | $[\ ]$ |
Visible Swan slopes: | $[]$ |
Means: | $\langle\ \rangle$ |
Rams: | $(\ )$ |
Jump set: | undefined |
Roots of unity: | $28560 = (13^{ 4 } - 1)$ |
Intermediate fields
$\Q_{13}(\sqrt{2})$, $\Q_{13}(\sqrt{13})$, $\Q_{13}(\sqrt{13\cdot 2})$, 13.4.1.0a1.1, 13.2.2.2a1.2, 13.2.2.2a1.1 |
Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.
Canonical tower
Unramified subfield: | 13.4.1.0a1.1 $\cong \Q_{13}(t)$ where $t$ is a root of
\( x^{4} + 3 x^{2} + 12 x + 2 \)
|
Relative Eisenstein polynomial: |
\( x^{2} + 13 \)
$\ \in\Q_{13}(t)[x]$
|
Ramification polygon
Residual polynomials: | $z + 2$ |
Associated inertia: | $1$ |
Indices of inseparability: | $[0]$ |
Invariants of the Galois closure
Galois degree: | $8$ |
Galois group: | $C_2\times C_4$ (as 8T2) |
Inertia group: | Intransitive group isomorphic to $C_2$ |
Wild inertia group: | $C_1$ |
Galois unramified degree: | $4$ |
Galois tame degree: | $2$ |
Galois Artin slopes: | $[\ ]$ |
Galois Swan slopes: | $[]$ |
Galois mean slope: | $0.5$ |
Galois splitting model: | $x^{8} - x^{7} + 4 x^{6} - 7 x^{5} + 19 x^{4} + 21 x^{3} + 36 x^{2} + 27 x + 81$ |