Publications associées à Exotic blow up solutions for the $\Box u^5$-focussing wave equation in $\mathbb{R}^3$

A Scaling Law for SPAD Pixel Miniaturization

The growing demands on compact and high-definition single-photon avalanche diode (SPAD) arrays have motivated researchers to explore pixel miniaturization techniques to achieve sub-10 μm pixels. The scaling of the SPAD pixel size has an impact on key perfo ...

2021

Thermally activated flow in models of amorphous solids

Marko Popovic, Matthieu Wyart, Wencheng Ji, Thomas Willem Jan de Geus

Amorphous solids yield at a critical value Sigma(c) of the imposed stress Sigma through a dynamical phase transition. While sharp in athermal systems, the presence of thermal fluctuations leads to the rounding of the transition and thermally activated flow ...

AMER PHYSICAL SOC2021

Staggered flux state for rectangular-lattice spin-1/2 Heisenberg antiferromagnets

Dmitri Ivanov, Bastien Dalla Piazza, Henrik Moodysson Rønnow, Noore Elahi Shaik

We investigate the spin-1/2 Heisenberg model on a rectangular lattice, using the Gutzwiller projected variational wave function known as the staggered flux state. Using Monte Carlo techniques, the variational parameters and instantaneous spin-spin correlat ...

AMER PHYSICAL SOC2020

Experimental study of impulse waves generated by viscoplastic fluid

Zhenzhu Meng

Landslide-generated waves, also called impulse waves, occur as a result of the intrusion of landslides (such as rock falls, debris flows, and avalanches) into bodies of water (such as lakes, reservoirs, and seas). The objective of this thesis was to study ...

EPFL2020

Time and space adaptivity of the wave equation discretized in time by a second-order scheme

Marco Picasso, Olga Gorynina

The aim of this paper is to obtain a posteriori error bounds of optimal order in time and space for the linear second-order wave equation discretized by the Newmark scheme in time and the finite element method in space. An error estimate is derived in the ...

2019

Stable Manifold for the Critical Non-Linear Wave Equation: A Fourier Theory Approach

Gérôme Graf

I will try to explain, without going into too much detail, how one can consider a non-linear wave equation as a dynamical system and what it brings to the study of its solutions. We begin by considering our model case, the non-linear Klein-Gordon equation ...

EPFL2019

A Class Of Large Global Solutions For The Wave-Map Equation

Joachim Krieger, Elisabetta Chiodaroli

In this paper we consider the equation for equivariant wave maps from R3+1 to S-3 and we prove global in forward time existence of certain C-infinity-smooth solutions which have infinite critical Sobolev norm (H) overdot(3/4) (R-3) x (H) overdot(1/2) (R-3) ...

2017

Optical wave evolution due to interaction with elastic wave in a phoxonic crystal slab waveguide

Sina Khorasani

Phoxonic crystal as a means of guiding and confining electromagnetic and elastic waves has already attracted attentions. Lack of exact knowledge on how these two types of waves interact inside this crystal and how electromagnetic wave evolves through this ...

Springer2017

Multiplicity Of Solutions For Linear Partial Differential Equations Using (Generalized) Energy Operators

Jean-Philippe Lucien Montillet

Families of energy operators and generalized energy operators have recently been introduced in the definition of the solutions of linear Partial Differential Equations (PDEs) with a particular application to the wave equation [ 15]. To do so, the author ha ...

Int Center Scientific Research & Studies2017

Seismic response of rock joints under obliquely incident wave

Yang Zou

Seismic response of joints which are found to be ubiquitous in rock masses is of great interest to rock engineers, geophysicists and seismologists. In the past years, wave propagation across rock joints has been the subject of extensive theoretical and exp ...

EPFL2016

Short-Wavelength Spin Waves in Yttrium Iron Garnet Micro-Channels on Silicon

Jean-Philippe Ansermet, Haiming Yu, Francesco Antonio Vetrò, Ping Che, Sa Tu, Yao Zhang

Yttrium iron garnet (YIG) has been widely used in spin wave studies thanks to its low Gilbert damping constant. However, most high-quality YIG films are grown on gadolinium gallium garnet (GGG) substrate, which makes it difficult to integrate with existing ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Wave propagation in the vicinities of rock fractures under obliquely incident wave

Lyesse Laloui, Jian Zhao, Yang Zou, Jing Li

Though obliquely incident plane wave across rock fractures has been extensively investigated by theoretical analysis, the quantitative identification of each wave emerged from fractures has not been achieved either in numerical simulation or laboratory exp ...

Springer Verlag2016

The role of fluctuations in ecological patterns and processes

Andrea Giometto

Fluctuations are ubiquitous in nature and are relevant for nearly every ecological process. The main sources of fluctuations in population abundances are demographic and environmental stochasticity, whose effect on local population dynamics, metapopulation ...

EPFL2015

A Scaling Law to Predict the Finite-Length Performance of Spatially-Coupled LDPC Codes

Rüdiger Urbanke

Spatially-coupled low-density parity-check (SC-LDPC) codes are known to have excellent asymptotic properties. Much less is known regarding their finite-length performance. We propose a scaling law to predict the error probability of finite-length spatially ...

Institute of Electrical and Electronics Engineers2015

Magnetic thin-film insulator with ultra-low spin wave damping for coherent nanomagnonics

Haiming Yu, Dirk Grundler

Wave control in the solid state has opened new avenues in modern information technology. Surface-acoustic-wave-based devices are found as mass market products in 100 millions of cellular phones. Spin waves (magnons) would offer a boost in today's data hand ...

Nature Publishing Group2014

Nondispersive Decay For The Cubic Wave Equation

Roland Donninger

We consider the hyperboloidal initial value problem for the cubic focusing wave equation (-partial derivative(2)(t) + Delta(x))nu(t, x) + nu(t, x)(3) = 0, x is an element of R-3 Without symmetry assumptions, we prove the existence of a codimension-4 Lipsch ...

Mathematical Science Publ2014

Nondispersive solutions to the $L^2$-critical half-wave equation

Joachim Krieger

We consider the focusing

L^2

-critical half-wave equation in one space dimension

i \partial_t u = D u - |u|^2 u,

where

D

denotes the first-order fractional derivative. Standard arguments show that there is a critical threshold

M_* > 0

such that all ...

Springer Verlag2013

Odd linking and bifurcation in gaps: the weakly indefinite case

In this paper, we consider nonlinear Schrodinger equations of the following type: -Delta u(x) + V (x) u(x) -q(x)|u(x)|sigma u(x) =lambda u(x), x is an element of R-N, u is an element of H-1(R-N) \ {0}, where N >= 2 and sigma > 0. We concentrate on situatio ...

Royal Society of Edinburgh Scotland Foundation, Cambridge2013

Global dynamics above the ground state energy for the one-dimensional NLKG equation

Joachim Krieger

In this paperwe obtain a global characterization of the dynamics of even solutions to the one-dimensional nonlinear Klein–Gordon (NLKG) equation on the line with focusing nonlinearity |u|p−1u, p > 5, provided their energy exceeds that of the ground state o ...

Springer Verlag2012

Two Positive Solutions of a Quasilinear Elliptic Dirichlet Problem

Charles Stuart

For a class of second order quasilinear elliptic equations we establish the existence of two non-negative weak solutions of the Dirichlet problem on a bounded domain, Omega. Solutions of the boundary value problem are critical points of C-1-functional on H ...

Birkhäuser-Verlag, Springer2011