Artículos (Álgebra)
https://hdl.handle.net/11441/10804
2019-11-19T06:08:11ZA rigid local system with monodromy group 2.J2
https://hdl.handle.net/11441/86652
A rigid local system with monodromy group 2.J2
We exhibit a rigid local system of rank six on the affine line in characteristic p = 5 whose arithmetic and geometric monodromy groups are the finite group 2.J2 (J2 the Hall-Janko
sporadic group) in one of its two (Galois-conjugate) irreducible representation of degree six.
2019-05-01T00:00:00ZTorsion homology and cellular approximation
https://hdl.handle.net/11441/85271
Torsion homology and cellular approximation
We describe the role of the Schur multiplier in the structure of the p-torsion of
discrete groups. More concretely, we show how the knowledge of H2G allows us to approximate many groups by colimits of copies of p-groups. Our examples include interesting families of noncommutative infinite groups, including Burnside groups, certain solvable groups and branch groups. We also provide a counterexample for a conjecture of Emmanuel Farjoun.
2019-02-06T00:00:00ZHomotopy theory of bicomplexes
https://hdl.handle.net/11441/85269
Homotopy theory of bicomplexes
We define two model structures on the category of bicomplexes
concentrated in the right half plane. The first model structure has weak
equivalences detected by the totalisation functor. The second model structure’s weak equivalences are detected by the E2-term of the spectral sequence associated to the filtration of the total complex by the horizontal degree. We then extend this result to twisted complexes.
2019-05-01T00:00:00ZPolynomial braid combing
https://hdl.handle.net/11441/84184
Polynomial braid combing
We prove that, for n ≥ 3, the minimal dimension of a model of the classifying
space of the braid group Bn, and of the pure braid group Pn, with respect to the
family of virtually cyclic groups is n.
2018-01-01T00:00:00Z