Browsing Analysis of Partial Differential Equations (APDE) by Title
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Spectral stability of Schrödinger operators with subordinated complex potentials
(20180628)We prove that the spectrum of Schroedinger operators in three dimensions is purely continuous and coincides with the nonnegative semiaxis for all potentials satisfying a formsubordinate smallness condition. By developing ... 
Spectral Transitions for AharonovBohm Laplacians on Conical Layers
(20160711)We consider the Laplace operator in a tubular neighbourhood of a conical surface of revolution, subject to an AharonovBohm magnetic field supported on the axis of symmetry and Dirichlet boundary conditions on the boundary ... 
Spherevalued harmonic maps with surface energy and the K13 problem
(201711)We consider an energy functional motivated by the celebrated K13 problem in the OseenFrank theory of nematic liquid crystals. It is defined for spherevalued functions and appears as the usual Dirichlet energy with an ... 
Static and Dynamical, Fractional Uncertainty Principles
(202103)We study the process of dispersion of lowregularity solutions to the Schrödinger equation using fractional weights (observables). We give another proof of the uncertainty principle for fractional weights and use it to get ... 
A strategy for selfadjointness of Dirac operators: Applications to the MIT bag model and deltashell interactions
(20161221)We develop an approach to prove selfadjointness of Dirac operators with boundary or transmission conditions at a $C^2$compact surface without boundary. To do so we are lead to study the layer potential induced by the ... 
Symmetry and Multiplicity of Solutions in a TwoDimensional Landau–de Gennes Model for Liquid Crystals
(20200520)We consider a variational twodimensional Landau–de Gennes model in the theory of nematic liquid crystals in a disk of radius R. We prove that under a symmetric boundary condition carrying a topological defect of degree ... 
The dynamics of vortex filaments with corners
(20150701)This paper focuses on surveying some recent results obtained by the author together with V. Banica on the evolution of a vortex filament with one corner according to the socalled binormal flow. The case of a regular polygon ... 
The initial value problem for the binormal flow with rough data
(20151231)In this article we consider the initial value problem of the binormal flow with initial data given by curves that are regular except at one point where they have a corner. We prove that under suitable conditions on the ... 
The Vortex Filament Equation as a Pseudorandom Generator
(20150801)In this paper, we consider the evolution of the socalled vortex filament equation (VFE), $$ X_t = X_s \wedge X_{ss},$$ taking a planar regular polygon of M sides as initial datum. We study VFE from a completely novel ... 
Three Observations on Commutators of Singular Integral Operators with BMO Functions
(20160701)Three observations on commutators of Singular Integral Operators with BMO functions are exposed, namely 1  The already known subgaussian local decay for the commutator, namely $\[\frac{1}{Q}\left\left\{x\in Q\, : ... 
Threedimensional coarsening dynamics of a conserved, nematic liquid crystalisotropic fluid mixture
(201709)We present a numerical investigation of the threedimensional coarsening dynamics of a nematic liquid crystalisotropic fluid mixture using a conserved phase field model. The model is a coupled system for a generalized ... 
Topics in Harmonic Analysis; commutators and directional singular integrals
(20200301)This dissertation focuses on two main topics: commutators and maximal directional operators. Our first topic will also distinguish between two cases: commutators of singular integral operators and BMO functions and ... 
Topological singular set of vectorvalued maps, I: application to manifoldconstrained Sobolev and BV spaces
(20190330)We introduce an operator $\mathbf{S}$ on vectorvalued maps $u$ which has the ability to capture the relevant topological information carried by $u$. In particular, this operator is defined on maps that take values in a ... 
Twoweight mixed norm estimates for a generalized spherical mean Radon transform acting on radial functions
(2018)We investigate a generalized spherical means operator, viz. generalized spherical mean Radon transform, acting on radial functions. We establish an integral representation of this operator and find precise estimates of ... 
Unique determination of the electric potential in the presence of a fixed magnetic potential in the plane
(201812)For electric and magnetic potentials with compact support, we consider the magnetic Schrödinger equation with fixed positive energy. Under a mild additional regularity hypothesis, and with fixed magnetic potential, we show ... 
Uniqueness and Properties of Distributional Solutions of Nonlocal Equations of Porous Medium Type
(20160901)We study the uniqueness, existence, and properties of bounded distributional solutions of the initial value problem for the anomalous diffusion equation $\partial_tu\mathcal{L}^\mu [\varphi (u)]=0$. Here $\mathcal{L}^\mu$ ... 
Uniqueness of degreeone Ginzburg–Landau vortex in the unit ball in dimensions N ≥ 7
(20180901)For ε>0, we consider the GinzburgLandau functional for RNvalued maps defined in the unit ball BN⊂RN with the vortex boundary data x on ∂BN. In dimensions N≥7, we prove that for every ε>0, there exists a unique global ... 
Uniqueness properties for discrete equations and Carleman estimates
(20170325)Using Carleman estimates, we give a lower bound for solutions to the discrete Schrödinger equation in both dynamic and stationary settings that allows us to prove uniqueness results, under some assumptions on the decay of ... 
Uniqueness properties of solutions to the BenjaminOno equation and related models
(20200315)We prove that if u1,u2 are real solutions of the BenjaminOno equation defined in (x,t)∈R×[0,T] which agree in an open set Ω⊂R×[0,T], then u1≡u2. We extend this uniqueness result to a general class of equations of BenjaminOno ... 
Uniqueness Properties of Solutions to the BenjaminOno equation and related models
(20190131)We prove that if u1, u2 are solutions of the Benjamin Ono equation defined in (x, t) ∈ R × [0, T ] which agree in an open set Ω ⊂ R × [0,T], then u1 ≡ u2. We extend this uniqueness result to a general class of equations ...