Centre de Recerca Matemàtica: Enviaments recents
Ara mostrant els elements 1-20 de 1306
On the ergodicity of infinite antisymmetric extensions of symmetric IETs
We consider skew product extensions over symmetric interval exchange transformations on the unit interval [0,1) with respect to the cocycle f = χ(0,½) - χ(½,1). We prove that for almost every interval exchange transformation ...
Ergodic properties of infinite extension of symmetric interval exchange transformations
We prove that skew products with the cocycle given by the function f(x) = a(x − 1/2) with a ̸= 0 are ergodic for every ergodic symmetric IET in the base, thus giving the full characterization of ergodic extensions in ...
Affine interval exchange maps with a singular conjugacy to an IET
We produce affine interval exchange transformations (AIETs) which are topologically conjugated to (standard) interval exchange maps (IETs) via a singular conjugacy, i.e. a diffeomorphism h of [0,1] which is C0 but not C1 ...
Sampling recovery of functions with mixed smoothness
Recently, a substantial progress in studying the problem of optimal sampling recovery was made in a number of papers. In particular, this resulted in some progress in studying sampling recovery on function classes with ...
Separating the Edges of a Graph by Cycles and by Subdivisions of K4
A separating system of a graph (Formula presented.) is a family (Formula presented.) of subgraphs of (Formula presented.) for which the following holds: for all distinct edges (Formula presented.) and (Formula presented.) ...
Lagrangian descriptors in geophysical flows: a survey
This survey focuses on the application of Lagrangian descriptors to reveal the geometry of phase space structures that determine transport in dynamical systems. We present diverse formulations of the method and examine ...
A parametrization algorithm to compute lower dimensional elliptic tori in Hamiltonian systems
We present an algorithm for the construction of lower dimensional elliptic tori in parametric Hamiltonian systems by means of the parametrization method with the tangent and normal frequencies being prescribed. This requires ...
Modelling large mass removal in adsorption columns
A novel mathematical model is developed to describe column adsorption when the contaminant constitutes a significant amount of the fluid. This requires tracking the variation of pressure and velocity, in addition to the ...
A note on the local behavior of the Taylor method for stiff ODEs
In this note we study the behavior of the coefficients of the Taylor method when computing the numerical solution of stiff Ordinary Differential Equations. First, we derive an asymptotic formula for the growth of the ...
Towards a Fluid Computer
In 1991, Moore (Nonlinearity 4:199–230, 1991) raised a question about whether hydrodynamics is capable of performing computations. Similarly, in 2016, Tao (J Am Math Soc 29(3):601–674, 2016) asked whether a mechanical ...
A Non-Parametric Estimation Method of the PopulationSize in Capture-Recapture Experiments With RightCensored Data
We present a new non-parametric approach for estimating the total number of animals or species when we only have information on the number of animals or species that have been observed once, twice, (Formula presented.), ...
Pebble trees
A pebble tree is an ordered tree where each node receives some colored pebbles, in such a way that each unary node receives at least one pebble, and each subtree has either one more or as many leaves as pebbles of each ...
On Darmon’s program for the generalized Fermat equation, I
In 2000, Darmon described a program to study the generalized Fermat equation using modularity of abelian varieties of GL 2-type over totally real fields. The original approach was based on hard open conjectures, which have ...
Smooth imploding solutions for 3D compressible fluids
Building upon the pioneering work of Merle, Raphaël, Rodnianski and Szeftel [67, 68, 69], we construct exact, smooth self-similar imploding solutions to the 3D isentropic compressible Euler equations for ideal gases for ...
Limit cycles and critical periods with non-hyperbolic slow-fast systems
By considering planar slow-fast systems with a curve of double singular points, we obtain lower bounds on the number of limit cycles of polynomial systems surrounding a single singular point, as well as on the number of ...
On the automorphism group of quotient modular curves
In this article, we determine the automorphism group of all the quotient modular curves of the modular curve X0(pq), where p,q are two distinct primes. In obtaining such results, we provide different insights to compute ...
On the local geometry of the moduli space of (2,2)-threefolds in A9
We study the local geometry of the moduli space of intermediate Jacobians of (2,2)-threefolds in P2× P2. More precisely, we prove that a composition of the second fundamental form of the Siegel metric in A9 restricted to ...
Examples of optimal Hölder regularity in semilinear equations involving the fractional Laplacian
We discuss the Hölder regularity of solutions to the semilinear equation involving the fractional Laplacian (−Δ)su=f(u) in one dimension. We put in evidence a new regularity phenomenon which is a combined effect of the ...
Nondensity results in high-dimensional stable Hamiltonian topology
We push forward the study of higher dimensional stable Hamiltonian topology by establishing two nondensity results. First, we prove that stable hypersurfaces are not (Formula presented.) -dense in any isotopy class of ...
Carleson conditions for weights: The quantitative small constant case
We investigate the small constant case of a characterization of A∞ weights due to Fefferman, Kenig and Pipher. In their work, Fefferman, Kenig and Pipher bound the logarithm of the A∞ constant by the Carleson norm of a ...
