Defining polynomial
\(x^{8} + 4 x^{6} + 8 x + 2\)
|
Invariants
Base field: | $\Q_{2}$ |
Degree $d$: | $8$ |
Ramification index $e$: | $8$ |
Residue field degree $f$: | $1$ |
Discriminant exponent $c$: | $24$ |
Discriminant root field: | $\Q_{2}$ |
Root number: | $1$ |
$\Aut(K/\Q_{2})$: | $C_1$ |
This field is not Galois over $\Q_{2}.$ | |
Visible Artin slopes: | $[3, \frac{7}{2}, \frac{7}{2}]$ |
Visible Swan slopes: | $[2,\frac{5}{2},\frac{5}{2}]$ |
Means: | $\langle1, \frac{7}{4}, \frac{17}{8}\rangle$ |
Rams: | $(2, 3, 3)$ |
Jump set: | $[1, 3, 7, 15]$ |
Roots of unity: | $2$ |
Intermediate fields
$\Q_{2}(\sqrt{2})$ |
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: |
\( x^{8} + 4 x^{6} + 8 x + 2 \)
|
Ramification polygon
Residual polynomials: | $z^4 + 1$,$z^3 + z + 1$ |
Associated inertia: | $1$,$3$ |
Indices of inseparability: | $[17, 14, 8, 0]$ |
Invariants of the Galois closure
Galois degree: | $96$ |
Galois group: | $C_2^3:A_4$ (as 8T33) |
Inertia group: | $C_2^2\wr C_2$ (as 8T18) |
Wild inertia group: | $C_2^2\wr C_2$ |
Galois unramified degree: | $3$ |
Galois tame degree: | $1$ |
Galois Artin slopes: | $[2, 2, 3, \frac{7}{2}, \frac{7}{2}]$ |
Galois Swan slopes: | $[1,1,2,\frac{5}{2},\frac{5}{2}]$ |
Galois mean slope: | $3.1875$ |
Galois splitting model: | $x^{8} - 8 x^{6} - 8 x^{5} + 42 x^{4} - 8 x^{3} - 16 x^{2} - 24 x + 23$ |