Zobrazeno 1 - 10
of 140
pro vyhledávání: '"MARGALIT, DAN"'
We give a quadratic-time algorithm to compute the stretch factor and the invariant measured foliations for a pseudo-Anosov element of the mapping class group. As input, the algorithm accepts a word (in any given finite generating set for the mapping
Externí odkaz:
http://arxiv.org/abs/2408.07596
Autor:
Caplinger, Noah, Margalit, Dan
We survey the theory of totally symmetric sets, with applications to homomorphisms of symmetric groups, braid groups, linear groups, and mapping class groups.
Comment: 21 pages
Comment: 21 pages
Externí odkaz:
http://arxiv.org/abs/2401.13739
We give a unified and self-contained proof of the Nielsen-Thurston classification theorem from the theory of mapping class groups and Thurston's characterization of rational maps from the theory of complex dynamics (plus various extensions of these).
Externí odkaz:
http://arxiv.org/abs/2309.06993
Building on work of Farb and the second author, we prove that the group of automorphisms of the fine curve graph for a surface is isomorphic to the group of homeomorphisms of the surface. This theorem is analogous to the seminal result of Ivanov that
Externí odkaz:
http://arxiv.org/abs/2108.04872
Publikováno v:
Compositio Math. 157 (2021) 1807-1852
We construct the first examples of normal subgroups of mapping class groups that are isomorphic to non-free right-angled Artin groups. Our construction also gives normal, non-free right-angled Artin subgroups of other groups, such as braid groups and
Externí odkaz:
http://arxiv.org/abs/2001.10587
Autor:
Kordek, Kevin, Margalit, Dan
We give a complete classification of homomorphisms from the commutator subgroup of the braid group on $n$ strands to the braid group on $n$ strands when $n$ is at least 7. In particular, we show that each nontrivial homomorphism extends to an automor
Externí odkaz:
http://arxiv.org/abs/1910.06941
We give a complete classification of homomorphisms from the braid group on $n$ strands to the braid group on $2n$ strands when $n$ is at least 5. We also classify endomorphisms of the braid group on 4 strands, as well as homomorphisms from the commut
Externí odkaz:
http://arxiv.org/abs/1910.00712
We give a simple algorithm that determines whether a given post-critically finite topological polynomial is Thurston equivalent to a polynomial. If it is, the algorithm produces the Hubbard tree; otherwise, the algorithm produces the canonical obstru
Externí odkaz:
http://arxiv.org/abs/1906.07680
Autor:
Kordek, Kevin, Margalit, Dan
We investigate the cohomology of the level 4 subgroup of the braid group, namely, the kernel of the mod 4 reduction of the Burau representation at $t=-1$. This group is also equal to the kernel of the mod 2 abelianization of the pure braid group. We
Externí odkaz:
http://arxiv.org/abs/1903.03119
Autor:
Margalit, Dan, Putman, Andrew
Publikováno v:
Proc. Roy. Soc. Edinburgh Sect. A. 150 (2020), no. 5, 2379-2386
We give a new proof of a theorem of D. Calegari that says that the Cayley graph of a surface group with respect to any generating set lying in finitely many mapping class group orbits has infinite diameter. This applies, for instance, to the generati
Externí odkaz:
http://arxiv.org/abs/1807.00833