To every compact orientable surface one can associate following Harvey Ha Ha a combinatorial object the so called complex of curves which is analogous to Tits buildings associated to semisimple Lie groups The basic result of the present paper is an analogue of a fundamental theorem of Tits for these complexes It asserts that every automorphism of the complex of curves of a surface is induced by...

Robin Harte Dedicated to Goldie Hawn, on her birthday Abstract We attempt to deconstruct the Arens-Royden Theorem. Suppose A is a Banach algebra (by default complex, with identity 1): we shall write 0.1 A−1 = {a ∈ A : 1 ∈ Aa∩aA} for the open subgroup of invertible elements, and A−1 0 for the connected component of the identity in A −1: it turns out ([8], [11] Theorem 7.11.4) that 0.2 A−1 0 = Ex...

We give a characterization of all cartesian products D1 × D2 ⊂ C for which the Kobayashi–Royden and Hahn pseudometrics coincide. In particular, we show that there exist domains in C for which Kobayashi–Royden and Hahn pseudometrics are different.

In this article we give an expository account of the holomorphic motion theorem based on work of Mãne-Sad-Sullivan, Bers-Royden, and Chirka. After proving this theorem, we show that tangent vectors to holomorphic motions have |ǫ log ǫ| moduli of continuity and then show how this type of continuity for tangent vectors can be combined with Schwarz’s lemma and integration over the holomorphic vari...

The Royden ideal boundary of a domain is the set of all points in the maximal ideal space of the domain's Royden algebra that do not lie in the domain. Elements of the Royden ideal boundary can be characterized as nets convergent in both the weak and Euclidean topologies that have no subnet which is a sequence. As with other function algebras, boundary bers can be deened as subsets of all point...

We prove an effective version of a theorem of Dufresnoy: For any set of 2n + 1 hyperplanes in general position in Pn, we find an explicit constant K such that for every holomorphic map f from the unit disc to the complement of these hyperplanes, we have f#(0) ≤ K, where f# denotes the norm of the derivative measured with respect to the Fubini-Study metric. This result gives an explicit lower bo...

We continue the research on structure of complex geodesics in tube domains over (bounded) convex bases. In some special cases a more explicit form than existing ones are provided. As one consequences our study an effective formula for Kobayashi—Royden metric domain $${T_{{\mathbb{B}_n}}}$$ at origin is given. The results natural way provide versions Schwarz Lemma harmonic mappings. also present...

Recently Loeb and Walsh [3] established several results concerning the Royden boundary in the axiomatic setting. This in effect generalizes theorems about H D-f unctions, Dirichlet-finite harmonic functions on surfaces to Riemannian manifolds, which are the most general carriers of these functions. Their results are however restricted to bounded H D-f unctions. Whether Nakai's [4] characterizat...

We simplify proof of the theorem that close to any pseudoholomorphic disk there passes a pseudoholomorphic disk of arbitrary close size with any pre-described sufficiently close direction. We apply these results to the Kobayashi and Hanh pseudodistances. It is shown they coincide in dimensions higher than four. The result is new even in the complex case. We aim here to prove the following state...