Publication

Coarse graining and large-N behavior of the d-dimensional N-clock model

Publications associées (32)

Broken-Symmetry Ground States of the Heisenberg Model on the Pyrochlore Lattice

The spin-1/2 Heisenberg model on the pyrochlore lattice is an iconic frustrated three-dimensional spin system with a rich phase diagram. Besides hosting several ordered phases, the model is debated to possess a spin-liquid ground state when only nearest-ne ...

American Physical Society2021

On the asymptotic behavior of solutions to the Vlasov-Poisson system

Klaus Martin Widmayer

We prove small data modified scattering for the Vlasov-Poisson system in dimension

d=3

using a method inspired from dispersive analysis. In particular, we identify a simple asymptotic dynamic related to the scattering mass. ...

2022

Collaborative Learning in the Jungle (Decentralized, Byzantine, Heterogeneous, Asynchronous and Nonconvex Learning)

Rachid Guerraoui, El Mahdi El Mhamdi, Le Nguyen Hoang, Sébastien Louis Alexandre Rouault, Arsany Hany Abdelmessih Guirguis, Sadegh Farhadkhani

We study Byzantine collaborative learning, where n nodes seek to collectively learn from each others' local data. The data distribution may vary from one node to another. No node is trusted, and f < n nodes can behave arbitrarily. We prove that collaborati ...

2021

Imaginary Multiplicative Chaos: Moments, Regularity And Connections To The Ising Model

Janne Matias Junnila

In this article we study imaginary Gaussian multiplicative chaos-namely a family of random generalized functions which can formally be written as e(iX(x)), where X is a log-correlated real-valued Gaussian field on R-d, that is, it has a logarithmic singula ...

INST MATHEMATICAL STATISTICS2020

Perturbative approach to tunneling and quantum interferences in spin clusters

Frédéric Mila, Ivo Aguiar Maceira

Collective tunneling is a ubiquitous phenomenon in finite-size spin clusters that shows up in systems as diverse as molecular magnets or spin clusters adsorbed at surfaces. The basic problem we explore is to understand how small flipping terms can cooperat ...

2020

A reflected forward-backward splitting method for monotone inclusions involving Lipschitzian operators

Volkan Cevher, Cong Bang Vu

In this paper, we propose a novel splitting method for finding a zero point of the sum of two monotone operators where one of them is Lipschizian. The weak convergence the method is proved in real Hilbert spaces. Applying the proposed method to composite m ...

2021

Thermal spin crossover in Fe(ii) and Fe(iii). Accurate spin state energetics at the solid state

Sergio Vela Llausi, Maria Fumanal Quintana

The thermal spin crossover (SCO) phenomenon refers to an entropy-driven spin transition in some materials based on d(6)-d(9) transition metal complexes. While its molecular origin is well known, intricate SCO behaviours are increasingly common, in which th ...

ROYAL SOC CHEMISTRY2020

Functional Inverse Problems on Spheres: Theory, Algorithms and Applications

Matthieu Martin Jean-André Simeoni

Many scientific inquiries in natural sciences involve approximating a spherical field -namely a scalar quantity defined over a continuum of directions- from generalised samples of the latter (e.g. directional samples, local averages, etc). Such an approxim ...

EPFL2020

Locally supported tangential vector, n-vector, and tensor fields

Christopher Brandt

We introduce a construction of subspaces of the spaces of tangential vector, n-vector, and tensor fields on surfaces. The resulting subspaces can be used as the basis of fast approximation algorithms for design and processing problems that involve tangenti ...

2020

Thermal CFTs in momentum space

Andrea Manenti

We study some aspects of conformal field theories at finite temperature in momentum space. We provide a formula for the Fourier transform of a thermal conformal block and study its analytic properties. In particular we show that the Fourier transform vanis ...

Springer Nature2020

On the asymptotic behavior of the solutions to parabolic variational inequalities

Maria Colombo

We consider various versions of the obstacle and thin-obstacle problems, we interpret them as variational inequalities, with non-smooth constraint, and prove that they satisfy a new constrained Lojasiewicz inequality. The difficulty lies in the fact that, ...

2020

Ising Model and Field Theory: Lattice Local Fields and Massive Scaling Limit

Sung Chul Park

This thesis is devoted to the study of the local fields in the Ising model. The scaling limit of the critical Ising model is conjecturally described by Conformal Field Theory. The explicit predictions for the building blocks of the continuum theory (spin a ...

EPFL2019

Publications associées (32)

Broken-Symmetry Ground States of the Heisenberg Model on the Pyrochlore Lattice

Giuseppe Carleo, Ao Chen

American Physical Society2021

On the asymptotic behavior of solutions to the Vlasov-Poisson system

Klaus Martin Widmayer

We prove small data modified scattering for the Vlasov-Poisson system in dimension

d=3

using a method inspired from dispersive analysis. In particular, we identify a simple asymptotic dynamic related to the scattering mass. ...

2022