Search results for "covers"
showing 6 items of 6 documents
Primeras consideraciones a la Ley Orga?nica 3/2021, de 24 de marzo, de regulación de la eutanasia. el reconocimiento de un nuevo derecho
2021
The aim of this paper is to carry out a brief study of the recent Organic Law 3/2021, of March 24, on the regulation of euthanasia (BOE. March 25, 2021) approved in Spain, from a constitutional perspective, highlighting its main aspects. The matter under study is not exempt from controversy because it covers legal, medical and ethical considerations of great complexity.
On hyperbolic type involutions
2001
We give a bound on the number of hyperbolic knots which are double covered by a fixed (non hyperbolic) manifold in terms of the number of tori and of the invariants of the Seifert fibred pieces of its Jaco-Shalen-Johannson decomposition. We also investigate the problem of finding the non hyperbolic knots with the same double cover of a hyperbolic one and give several examples to illustrate the results.
Triple planes with $p_g=q=0$
2019
We show that general triple planes with p_g=q=0 belong to at most 12 families, that we call surfaces of type I,..., XII, and we prove that the corresponding Tschirnhausen bundle is direct sum of two line bundles in cases I, II, III, whereas is a rank 2 Steiner bundle in the remaining cases. We also provide existence results and explicit constructions for surfaces of type I,..., VII, recovering all classical examples and discovering several new ones. In particular, triple planes of type VII provide counterexamples to a wrong claim made in 1942 by Bronowski.
Mappings of Finite Distortion : Compactness of the Branch Set
2017
We show that an entire branched cover of finite distortion cannot have a compact branch set if its distortion satisfies a certain asymptotic growth condition. We furthermore show that this bound is strict by constructing an entire, continuous, open and discrete mapping of finite distortion which is piecewise smooth, has a branch set homeomorphic to an (n - 2)-dimensional torus and distortion arbitrarily close to the asymptotic bound. Peer reviewed
Non-equivalent hyperbolic knots
2002
We construct, for each integer n 3, pairs of non-equivalent hyperbolic knots with the same 2fold and n-fold cyclic branched covers. We also discuss necessary conditions for such pairs of knots to exist. 2001 Elsevier Science B.V. All rights reserved. MSC: primary 57M25; secondary 57M12, 57M50
Proteggere e Valorizzare: una buona pratica per i siti archeologici
2014
Tra i beni culturali quelli archeologici hanno più animato il dibattito culturale sul rapporto tra conservazione e loro messa in valore. La fragilità con cui la materia ci viene consegnata dalla storia, la frammentarietà del reperto, la scarsa disponibilità di risorse finanziarie, anche in relazione alla vastità del patrimonio a noi pervenuto, impongono interventi mirati e talvolta urgenti per la salvaguardia e la conservazione dei beni archeologici. Ma la sola conservazione non può però costituire l’obiettivo ultimo dell’intervento: poiché i beni archeologici rappresentano il nostro lontano passato è anche necessario recuperarne il valore e comunicarne l’identità. La conoscenza storica, st…