Zobrazeno 1 - 10
of 86
pro vyhledávání: '"Piergallini, Riccardo"'
In this paper, we give a new direct proof of a result by Bobtcheva and Piergallini that provides finite algebraic presentations of two categories, denoted $3\mathrm{Cob}$ and $4\mathrm{HB}$, whose morphisms are manifolds of dimension $3$ and $4$, res
Externí odkaz:
http://arxiv.org/abs/2312.15986
Autor:
Arezzo, Claudio, Balducci, Federico, Piergallini, Riccardo, Scardicchio, Antonello, Vanoni, Carlo
It is well known that, if the initial conditions have sufficiently high energy density, the dynamics of the classical Discrete Non-Linear Schr\"odinger Equation (DNLSE) on a lattice shows a form of breaking of ergodicity, with a finite fraction of th
Externí odkaz:
http://arxiv.org/abs/2102.10298
In this work, we begin the study of a new class of dynamical systems determined by interval maps generated by the symbolic action of erasing substitution rules. We do this by discussing in some detail the geometric, analytical, dynamical and arithmet
Externí odkaz:
http://arxiv.org/abs/2102.01674
Autor:
Morresi, Tommaso, Binosi, Daniele, Simonucci, Stefano, Piergallini, Riccardo, Roche, Stephan, Pugno, Nicola M., Taioli, Simone
Analogue gravitational systems are becoming an increasing popular way of studying the behaviour of quantum systems in curved spacetime. Setups based on ultracold quantum gases in particular, have been recently harnessed to explore the thermal nature
Externí odkaz:
http://arxiv.org/abs/1907.08960
Autor:
Piergallini, Riccardo, Zuddas, Daniele
We provide a complete set of two moves that suffice to relate any two open book decompositions of a given 3-manifold. One of the moves is the usual plumbing with a positive or negative Hopf band, while the other one is a special local version of Hare
Externí odkaz:
http://arxiv.org/abs/1801.01858
Publikováno v:
Signal & Image Processing: An International Journal, 8(5), 29-43, 2017
We propose a new gradient-based method for the extraction of the orientation field associated to a fingerprint, and a regularisation procedure to improve the orientation field computed from noisy fingerprint images. The regularisation algorithm is ba
Externí odkaz:
http://arxiv.org/abs/1711.03214
Autor:
Piergallini, Riccardo, Zuddas, Daniele
We give necessary and sufficient conditions for a 4-manifold to be a branched covering of $CP^2$, $S^2\times S^2$, $S^2 \mathbin{\tilde\times} S^2$ and $S^3 \times S^1$, which are expressed in terms of the Betti numbers and the intersection form of t
Externí odkaz:
http://arxiv.org/abs/1707.03667
Autor:
Piergallini, Riccardo, Zuddas, Daniele
Publikováno v:
Journal of the London Mathematical Society 100 (2019) No. 1, 1-16
We provide new branched covering representations for bounded and/or non-compact 4-manifolds, which extend the known ones for closed 4-manifolds. Assuming $M$ to be a connected oriented PL 4-manifold, our main results are the following: (1) if $M$ is
Externí odkaz:
http://arxiv.org/abs/1602.07459
Autor:
Isola, Stefano, Piergallini, Riccardo
We introduce the concept of a generic Euclidean triangle $\tau$ and study the group $G_\tau$ generated by the reflection across the edges of $\tau$. In particular, we prove that the subgroup $T_\tau$ of all translations in $G_\tau$ is free abelian of
Externí odkaz:
http://arxiv.org/abs/1405.1881
Let $G_{g,b}$ be the set of all uni/trivalent graphs representing the combinatorial structures of pant decompositions of the oriented surface of genus $g$ with $b$ boundary components. We describe the set $A_{g,b}$ of all automorphisms of graphs in $
Externí odkaz:
http://arxiv.org/abs/1111.3515