Surface braid groups, Finite Heisenberg covers and double Kodaira fibrations

نویسندگان

چکیده

We exhibit new examples of double Kodaira fibrations by using finite Galois covers a product $\Sigma_b \times \Sigma_b$, where $\Sigma_b$ is smooth projective curve genus $b \geq 2$. Each cover obtained providing an explicit group epimorphism from the pure braid $\mathsf{P}_2(\Sigma_b)$ to some Heisenberg group. In this way, we are able show that every $b$ base fibration; moreover, number pairwise non-isomorphic fibred surfaces fibering over fixed at least $\boldsymbol{\omega}(b+1)$, $\boldsymbol{\omega} \colon \mathbb{N} \to \mathbb{N}$ stands for arithmetic function counting distinct prime factors positive integer. As particular case our general construction, obtain real $4$-manifold signature $144$ can be realized as surface bundle $2$, with fibre $325$, in two different ways. This provides (to knowledge) first "double" solution problem Kirby's list low-dimensional topology.

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Double Kodaira Fibrations

The existence of a Kodaira fibration, i.e., of a fibration of a compact complex surface S onto a complex curve B which is a differentiable but not a holomorphic bundle, forces the geographical slope ν(S) = c 1 (S)/c2(S) to lie in the interval (2, 3). But up to now all the known examples had slope ν(S) ≤ 2 + 1/3. In this paper we consider a special class of surfaces admitting two such Kodaira fi...

متن کامل

Artin Covers of the Braid Groups

Computation of fundamental groups of Galois covers recently led to the construction and analysis of Coxeter covers of the symmetric groups [RTV]. In this paper we consider analog covers of Artin’s braid groups, and completely describe the induced geometric extensions of the braid group.

متن کامل

Diffeomorphisms, Symplectic Forms, and Kodaira Fibrations

As was recently pointed out by McMullen and Taubes [6], there are 4manifolds for which the diffeomorphism group does not act transitively on the deformation classes of orientation-compatible symplectic structures. This note points out a huge class of rather different examples, arising as orientation-reversed versions of some complex surfaces constructed by Kodaira [3]. Supported in part by NSF ...

متن کامل

Questions on Surface Braid Groups

We provide new group presentations for surface braid groups which are positive. We study some properties of such presentations and we solve the conjugacy problem in a particular case.

متن کامل

Embeddings of graph braid and surface groups in right-angled Artin groups and braid groups

We prove by explicit construction that graph braid groups and most surface groups can be embedded in a natural way in right-angled Artin groups, and we point out some consequences of these embedding results. We also show that every right-angled Artin group can be embedded in a pure surface braid group. On the other hand, by generalising to rightangled Artin groups a result of Lyndon for free gr...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Annali della Scuola normale superiore di Pisa. Classe di scienze

سال: 2021

ISSN: ['0391-173X', '2036-2145']

DOI: https://doi.org/10.2422/2036-2145.201908_004