Defining polynomial
\(x^{8} + 8 x^{6} + 8 x^{5} + 8 x^{2} + 18\)
|
Invariants
Base field: | $\Q_{2}$ |
Degree $d$: | $8$ |
Ramification index $e$: | $8$ |
Residue field degree $f$: | $1$ |
Discriminant exponent $c$: | $28$ |
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: | $[3, 4, \frac{17}{4}]$ |
Visible Swan slopes: | $[2,3,\frac{13}{4}]$ |
Means: | $\langle1, 2, \frac{21}{8}\rangle$ |
Rams: | $(2, 4, 5)$ |
Jump set: | $[1, 3, 7, 15]$ |
Roots of unity: | $2$ |
Intermediate fields
$\Q_{2}(\sqrt{-2})$, 2.1.4.11a1.1 |
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: |
\( x^{8} + 8 x^{6} + 8 x^{5} + 8 x^{2} + 18 \)
|
Ramification polygon
Residual polynomials: | $z^4 + 1$,$z^2 + 1$,$z + 1$ |
Associated inertia: | $1$,$1$,$1$ |
Indices of inseparability: | $[21, 16, 8, 0]$ |
Invariants of the Galois closure
Galois degree: | $32$ |
Galois group: | $C_2^3:C_4$ (as 8T19) |
Inertia group: | $C_2^3:C_4$ (as 8T19) |
Wild inertia group: | $C_2^3:C_4$ |
Galois unramified degree: | $1$ |
Galois tame degree: | $1$ |
Galois Artin slopes: | $[2, 3, \frac{7}{2}, 4, \frac{17}{4}]$ |
Galois Swan slopes: | $[1,2,\frac{5}{2},3,\frac{13}{4}]$ |
Galois mean slope: | $3.8125$ |
Galois splitting model: | $x^{8} - 4 x^{6} + 10 x^{4} + 4 x^{2} + 1$ |