Defining polynomial
\(x^{8} + 2 x^{4} + 4 x^{3} + 6\)
|
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: | $1$ |
$\Aut(K/\Q_{2})$: | $C_2$ |
This field is not Galois over $\Q_{2}.$ | |
Visible Artin slopes: | $[2, \frac{8}{3}, \frac{8}{3}]$ |
Visible Swan slopes: | $[1,\frac{5}{3},\frac{5}{3}]$ |
Means: | $\langle\frac{1}{2}, \frac{13}{12}, \frac{11}{8}\rangle$ |
Rams: | $(1, \frac{7}{3}, \frac{7}{3})$ |
Jump set: | $[1, 2, 4, 16]$ |
Roots of unity: | $2$ |
Intermediate fields
$\Q_{2}(\sqrt{-5})$, 2.1.4.8a1.2 |
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: |
\( x^{8} + 2 x^{4} + 4 x^{3} + 6 \)
|
Ramification polygon
Residual polynomials: | $z^4 + 1$,$z + 1$ |
Associated inertia: | $1$,$1$ |
Indices of inseparability: | $[11, 11, 4, 0]$ |
Invariants of the Galois closure
Galois degree: | $48$ |
Galois group: | $C_2\times S_4$ (as 8T24) |
Inertia group: | $C_2\times A_4$ (as 8T13) |
Wild inertia group: | $C_2^3$ |
Galois unramified degree: | $2$ |
Galois tame degree: | $3$ |
Galois Artin slopes: | $[2, \frac{8}{3}, \frac{8}{3}]$ |
Galois Swan slopes: | $[1,\frac{5}{3},\frac{5}{3}]$ |
Galois mean slope: | $2.3333333333333335$ |
Galois splitting model: | $x^{8} - 4 x^{7} + 4 x^{6} - 6 x^{4} + 12 x^{3} - 2$ |