CRM Articles: Enviaments recents
Ara mostrant els elements 1-20 de 713
Packing large balanced trees into bipartite graphs
We prove that for every gamma>0 there exists n(0)is an element of N such that for every n >= n(0) any family of up to n(1/2-gamma) trees having at most (1-gamma)n vertices in each bipartition class can be packed into ...
Capturing the short-term characteristics of a barred galaxy from a single snapshot
Using a dataset of stars from a barred galaxy that provides instantaneous positions and velocities in the sky, we propose a method to identify its key structures, such as the central bar and spiral arms, and to determine ...
Efficient computation of non-archimedean theta functions
We describe an efficient iterative algorithm for the computation of theta functions of non-archimedean Schottky groups and, more generally, of (non-archimedean) discontinuous groups.
Phylogenetic Invariants: From the General Markov to Equivariant Models
In the last decade, some algebraic tools have been successfully applied to phylogenetic reconstruction. These tools are mainly based on the knowledge of equations describing algebraic varieties associated to Markov processes ...
Representational drift as the consequence of ongoing memory storage
Memory systems with biologically constrained synapses have been the topic of intense theoretical study for over thirty years. Perhaps the most fundamental and far-reaching finding from this work is that the storage of new ...
The period of the limit cycle bifurcating from a persistent polycycle
We consider smooth families of planar polynomial vector fields {X mu}mu is an element of Lambda, where Lambda is an open subset of RN, for which there is a hyperbolic polycycle Gamma that is persistent (i.e., such that ...
A connection between quantum dot Dirac operators and ∂ˉ-Robin Laplacians in the context of shape optimization problems
This work addresses Faber-Krahn-type inequalities for quantum dot Dirac operators with nonnegative mass on bounded domains in R2. We show that this family of inequalities is equivalent to a family of Faber-Krahn-type ...
On a Countable Sequence of Homoclinic Orbits Arising Near a Saddle–Center Point
Exponential small splitting of separatrices in the singular perturbation theory leads generally to nonvanishing oscillations near a saddle-center point and to nonexistence of a true homoclinic orbit. It was conjectured ...
The ∂ˉ-Robin Laplacian
We study the family of operators {ℛ_a}_(a∈[0,+∞))associated to the Robin-type problems in a bounded domain Ω⊂R^2 {︄−Δu=f in Ω, 2ν¯∂_(z¯)u+au=0 on ∂Ω, and their dependency on the boundary parameter a as it moves along ...
Explicit minimisers for anisotropic Riesz energies
In this paper we characterise the energy minimisers of a class of nonlocal interaction energies where the attraction is quadratic, and the repulsion is Riesz-like and anisotropic. In particular we show that, if the Fourier ...
Inner functions, Möbius distortion and angular derivatives
We prove that an inner function has finite L(p)-entropy if and only if its accumulated Mobius distortion is in L-p, 0 < p < infinity. We also study the support of the positive singular measures such that their corresponding ...
On the dimension of the boundaries of attracting basins of entire maps
Let f : C -> C be a transcendental entire map from the Eremenko-Lyubich class B, and let zeta be an attracting periodic point of period p. We prove that the boundaries of components of the attracting basin of (the orbit ...
The Rado multiplicity problem in vector spaces over finite fields
We study an analogue of the Ramsey multiplicity problem for additive structures, in particular establishing the minimum number of monochromatic 3-APs in 3-colorings of F3n as well as obtaining the first non-trivial lower ...
Marcinkiewicz–Zygmund inequalities in quasi-Banach function spaces
We obtain Marcinkiewicz-Zygmund (MZ) inequalities in various Banach and quasi-Banach spaces under minimal structural assumptions. Our main results show that the Bernstein inequality in a general quasi-Banach function lattice ...
Back to normal? a method to test and correct a shock impact on healthcare usage frequency data
A method based on Bayesian structural time series is proposed to predict healthcare usage trends and to test for changes in the series levels during or after an abnormal year, such as that of the 2020 COVID-19 pandemic. ...
KAM algorithms for Lagrangian tori in time-quasi-periodic Hamiltonian systems
In this paper, we present an algorithm to compute (fiberwise) Lagrangian tori in periodic and quasi-periodic Hamiltonian systems, whose convergence is proved in [1], and an algorithm to continue them with respect to ...
Kahane–Katznelson–de Leeuw theorem and absolute convergence of Fourier series
We extend the Kahane-Katznelson-de Leeuw theorem to smoothness spaces by showing that for any g is an element of W-l,W-2(T-d), there exists a function f is an element of C-l (T-d) satisfying |f (<^>)(n)|>=|g(<^>)(n)| and ...
Existence and nonexistence of invariant curves of coin billiards
In this paper we consider the coin billiard introduced by M. Bialy. It is a modification of the classical billiard, obtained as the return map of a nonsmooth geodesic flow on a cylinder that has homeomorphic copies of a ...
The modular automorphisms of quotientmodular curves
We obtain the modular automorphism group of any quotient modular curve of level , with . In particular, we obtain some unexpected automorphisms of order 3 that appear for the quotient modular curves when the Atkin-Lehner ...
Note on Fourier inequalities
We prove that the Hausdorff-Young inequality parallel to(f) over cap parallel to(q(center dot)) <= C parallel to F parallel to(p(center dot)) with q(x) = p '(1/x) and p(center dot) even and non-decreasing holds in variable ...
