Defining polynomial
\(x^{8} + 16 x^{5} + 4 x^{4} + 16 x^{3} + 2\)
|
Invariants
Base field: | $\Q_{2}$ |
Degree $d$: | $8$ |
Ramification index $e$: | $8$ |
Residue field degree $f$: | $1$ |
Discriminant exponent $c$: | $31$ |
Discriminant root field: | $\Q_{2}(\sqrt{2})$ |
Root number: | $1$ |
$\Aut(K/\Q_{2})$: | $C_4$ |
This field is not Galois over $\Q_{2}.$ | |
Visible Artin slopes: | $[3, 4, 5]$ |
Visible Swan slopes: | $[2,3,4]$ |
Means: | $\langle1, 2, 3\rangle$ |
Rams: | $(2, 4, 8)$ |
Jump set: | $[1, 3, 7, 15]$ |
Roots of unity: | $2$ |
Intermediate fields
$\Q_{2}(\sqrt{2})$, 2.1.4.11a1.9 |
Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.
Canonical tower
Unramified subfield: | $\Q_{2}$ |
Relative Eisenstein polynomial: |
\( x^{8} + 16 x^{5} + 4 x^{4} + 16 x^{3} + 2 \)
|
Ramification polygon
Residual polynomials: | $z^4 + 1$,$z^2 + 1$,$z + 1$ |
Associated inertia: | $1$,$1$,$1$ |
Indices of inseparability: | $[24, 16, 8, 0]$ |
Invariants of the Galois closure
Galois degree: | $16$ |
Galois group: | $\OD_{16}$ (as 8T7) |
Inertia group: | $C_8$ (as 8T1) |
Wild inertia group: | $C_8$ |
Galois unramified degree: | $2$ |
Galois tame degree: | $1$ |
Galois Artin slopes: | $[3, 4, 5]$ |
Galois Swan slopes: | $[2,3,4]$ |
Galois mean slope: | $3.875$ |
Galois splitting model: | $x^{8} + 120 x^{6} - 3540 x^{4} + 450$ |