Concept
Symmetry of second derivatives
Related publications (26)
Null energy constraints on two-dimensional RG flows
We study applications of spectral positivity and the averaged null energy condition (ANEC) to renormalization group (RG) flows in two-dimensional quantum field theory. We find a succinct new proof of the Zamolodchikov c-theorem, and derive further independ ...
New York2024Diversity of radial spin textures in chiral materials
Oleg Yazyev, Daniel Gosalbez Martinez, Alberto Crepaldi
We introduce a classification of the radial spin textures in momentum space that emerge at the high-symmetry points in crystals characterized by nonpolar chiral point groups (D2, D3, D4, D6, T, O). Based on the symmetry constraints imposed by these point g ...
College Pk2023Learning of Continuous and Piecewise-Linear Functions With Hessian Total-Variation Regularization
Michaël Unser, Shayan Aziznejad, Joaquim Gonçalves Garcia Barreto Campos
We develop a novel 2D functional learning framework that employs a sparsity-promoting regularization based on second-order derivatives. Motivated by the nature of the regularizer, we restrict the search space to the span of piecewise-linear box splines shi ...
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022Accurate equilibrium-based interlaminar stress recovery for isogeometric laminated composite Kirchhoff plates
Pablo Antolin Sanchez, Alessandro Reali
Despite the accelerated deployment of laminated composites in a wide variety of markets due to their peculiar engineering features, the design of those materials is often restrained by the lack of cost-efficient modeling techniques. In fact, the existing s ...
ELSEVIER SCI LTD2021On the choice of metric in gradient-based theories of brain function
Wulfram Gerstner, Johanni Michael Brea, Jean-Pascal Théodor Pfister
The idea that the brain functions so as to minimize certain costs pervades theoretical neuroscience. Because a cost function by itself does not predict how the brain finds its minima, additional assumptions about the optimization method need to be made to ...
2020Applying SHARK-X to perform data assimilation with the LWR-PROTEUS Phase II integral experiments
Andreas Pautz, Mathieu Hursin, Daniel Jerôme Siefman
Data assimilation methods have recently been implemented in the sensitivity analysis and uncertainty quantification tool SHARK-X. This paper presents how they were used with sensitivity coefficients and randomly-sampled nuclear data to simulate integral pa ...
PERGAMON-ELSEVIER SCIENCE LTD2020A Graphical Description of Partial Exchangeability
Mats Julius Stensrud, Aaron Leor Sarvet
Partial exchangeability is sufficient for the identification of some causal effects of interest. Here we review the use of common graphical tools and the sufficient component cause model in the context of partial exchangeability. We illustrate the utility ...
2020An optimized self-sensing piezoelectric cantilever for micro-robotic applications
Yves Perriard, Louis Antoine Masson, Xinchang Liu
Quasi-static piezoelectric actuators are used in micro-robotics due to the small displacements they can achieve, and they have been proven to be suitable for Self-Sensing Actuation (SSA) applications. The morphology and material of an actuator, and therefo ...
2019Nonperturbative test of consistency relations and their violation
In this paper, we verify the large scale structure consistency relations using N-body simulations, including modes in the highly nonlinear regime. These relations (pointed out by Kehagias & Riotto and Peloso & Pietroni) follow from the symmetry of the dyna ...
AMER PHYSICAL SOC2019Sur quelques équations aux dérivées partielles en lien avec le lemme de Poincaré
In this thesis, we study two distinct problems.
The first problem consists of studying the linear system of partial differential equations which consists of taking a k-form, and applying the exterior derivative 'd' to it and add the wedge product with a 1- ...
EPFL2018