We prove new cases of the inverse Galois problem by considering the residual Galois representations arising from a fixed newform. Specific choices of weight 3 newforms will show that there are Galois extensions of Q with Galois group PSL2(Fp) for all primes p and PSL2(Fp3) for all odd primes p ≡ ±2,±3,±4,±6 (mod 13).

Recall that the birational anabelian conjecture originating in ideas presented in Grothendieck’s Esquisse d’un Programme [G1] and Letter to Faltings [G2], asserts roughly the following: First, there should exist a group theoretical recipe by which one can recognize the absolute Galois groups GK of finitely generated infinite fields K among all the profinite groups. Second, if G = GK is such an ...

In abstract algebra, we considered finite Galois extensions of fields with their Galois groups. Here, we noticed a correspondence between the intermediate fields and the subgroups of the Galois group; specifically, there is an inclusion reversing bijection that takes a subgroup to its fixed field. We notice a similar relationship in topology between the fundamental group and covering spaces. Th...

We give sufficient conditions for a differential equation to have a given semisimple group as its Galois group. For any group G with G0 = G1 · . . . · Gr where each Gi is a simple group of type Al, Cl, Dl, E6 or E7, we construct a differential equation over C(x) having Galois group G.

We study the degree of elimination of imaginaries needed for the three main applications: to have canonical bases for types over models, to define strong types as types over algebraically closed sets and to have a Galois correspondence between definably closed sets B such that A ⊆ B ⊆ acl(A) and closed subgroups of the Galois group Aut(acl(A)/A). We also characterize when the topology of the Ga...

This paper concerns the description of holomorphic extensions of algebraic number fields. After expanding the notion of adele class group to number fields of infinite degree over Q, a hyperbolized adele class group ŜK is assigned to every number field K/Q. The projectivization of the Hardy space PH•[K] of graded-holomorphic functions on ŜK possesses two operations ⊕ and ⊗ giving it the structur...

Using the principle that characteristic polynomials of matrices obtained from elements of a reductive group G over Q typically have splitting field with Galois group isomorphic to the Weyl group of G, we construct an explicit monic integral polynomial of degree 240 whose splitting field has Galois group the Weyl group of the exceptional group of type E8.

Let L|K be a Galois extension of fields with finite Galois group G. Greither and Pareigis [GP87] showed that there is a bijection between Hopf Galois structures on L|K and regular subgroups of Perm(G) normalized by G, and Byott [By96] translated the problem into that of finding equivalence classes of embeddings of G in the holomorph of groups N of the same cardinality as G. In [CCo06] we showed...

Fix an integer n = 3. We show that the alternating group An appears as Galois group over any Hilbertian field of characteristic different from 2. In characteristic 2, we prove the same when n is odd. We show that any quadratic extension of Hilbertian fields of characteristic different from 2 can be embedded in an Sn–extension (i.e. a Galois extension with the symmetric group Sn as Galois group)...