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Defining polynomial

Copy content comment:Define the p-adic field
 
Copy content sage:Prec = 100 # Default precision of 100 Q13 = Qp(13, Prec); x = polygen(QQ) L.<t> = Q13.extension(x^2 + 12*x + 2) K.<a> = L.extension(x^2 + 13)
 
Copy content magma:Prec := 100; // Default precision of 100 Q13 := pAdicField(13, Prec); K := LocalField(Q13, Polynomial(Q13, [17, 48, 148, 24, 1]));
 

$( x^{2} + 12 x + 2 )^{2} + 13$ Copy content Toggle raw display

Copy content comment:Defining polynomial
 
Copy content sage:K.defining_polynomial()
 
Copy content magma:DefiningPolynomial(K);
 

Invariants

Base field: $\Q_{13}$
Copy content comment:Base field Qp
 
Copy content sage:K.base()
 
Copy content magma:Q13;
 
Degree $d$: $4$
Copy content comment:Degree over Qp
 
Copy content sage:K.absolute_degree()
 
Copy content magma:Degree(K);
 
Ramification index $e$:$2$
Copy content comment:Ramification index
 
Copy content sage:K.absolute_e()
 
Copy content magma:RamificationIndex(K);
 
Residue field degree $f$:$2$
Copy content comment:Residue field degree (Inertia degree)
 
Copy content sage:K.absolute_f()
 
Copy content magma:InertiaDegree(K);
 
Discriminant exponent $c$:$2$
Copy content comment:Discriminant exponent
 
Copy content magma:Valuation(Discriminant(K));
 
Discriminant root field:$\Q_{13}$
Root number: $-1$
$\Aut(K/\Q_{13})$ $=$ $\Gal(K/\Q_{13})$: $C_2^2$
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:$168 = (13^{ 2 } - 1)$
Copy content comment:Roots of unity
 
Copy content sage:len(K.roots_of_unity())
 

Intermediate fields

$\Q_{13}(\sqrt{13})$, $\Q_{13}(\sqrt{13\cdot 2})$, $\Q_{13}(\sqrt{2})$

Fields in the database are given up to isomorphism. Isomorphic intermediate fields are shown with their multiplicities.

Canonical tower

Unramified subfield:$\Q_{13}(\sqrt{2})$ $\cong \Q_{13}(t)$ where $t$ is a root of \( x^{2} + 12 x + 2 \) Copy content Toggle raw display
Copy content comment:Maximal unramified subextension
 
Copy content sage:K.maximal_unramified_subextension()
 
Relative Eisenstein polynomial: \( x^{2} + 13 \) $\ \in\Q_{13}(t)[x]$ Copy content Toggle raw display

Ramification polygon

Residual polynomials:$z + 2$
Associated inertia:$1$
Indices of inseparability:$[0]$

Invariants of the Galois closure

Galois degree: $4$
Galois group: $C_2^2$ (as 4T2)
Inertia group: Intransitive group isomorphic to $C_2$
Wild inertia group: $C_1$
Galois unramified degree: $2$
Galois tame degree: $2$
Galois Artin slopes: $[\ ]$
Galois Swan slopes: $[\ ]$
Galois mean slope: $0.5$
Galois splitting model:$x^{4} - 3 x^{2} + 25$