Concept

Vecteur de Killing

Publications associées (33)

Cosmological constraints on deviations from Lorentz invariance in gravity and dark matter

Julien Lesgourgues, Sergey Sibiryakov, Diego Blas Temino, Mikhail Ivanov, Benjamin Audren

We consider a scenario where local Lorentz invariance is violated by the existence of a preferred time direction at every space-time point. This scenario can arise in the context of quantum gravity and its description at low energies contains a unit time-l ...

Iop Publishing Ltd2015

Time reversal symmetry in time-dependent correlation functions for systems in a constant magnetic field

Sara Bonella

A generalised time reversal symmetry for systems subject to a constant magnetic field is introduced, based on the analogy between the evolution equations of these systems and those of a system subject to shear. This generalisation makes it possible to deri ...

Epl Association, European Physical Society2014

Right-Protected Data Publishing with Provable Distance-Based Mining

Michail Vlachos, Nikolaos Freris

Protection of one's intellectual property is a topic with important technological and legal facets. We provide mechanisms for establishing the ownership of a dataset consisting of multiple objects. The algorithms also preserve important properties of the d ...

Ieee Computer Soc2014

Geodesic distance for right invariant Sobolev metrics of fractional order on the diffeomorphism group. II

Martins Bruveris, Martin Bauer

The geodesic distance vanishes on the group of compactly supported diffeomorphisms of a Riemannian manifold of bounded geometry, for the right invariant weak Riemannian metric which is induced by the Sobolev metric of order on the Lie algebra of vector fie ...

Springer Verlag2013

Low-Rank Matrix Completion By Riemannian Optimization

The matrix completion problem consists of finding or approximating a low-rank matrix based on a few samples of this matrix. We propose a new algorithm for matrix completion that minimizes the least-square distance on the sampling set over the Riemannian ma ...

Siam Publications2013

Thermodynamics of a continuous medium with electric and magnetic dipoles

Jean-Philippe Ansermet, Sylvain Bréchet

The thermodynamics of an electrically charged, multicomponent fluid with spontaneous electric and magnetic dipoles is analysed in the presence of electromagnetic fields. Taking into account the chemical composition of the current densities and stress tenso ...

Springer Verlag2013

A geometric framework for registration of sparse images

Pascal Frossard, Alhussein Fawzi

We examine the problem of image registration when images have a sparse representation in a dictionary of geometric features. We propose a novel algorithm for aligning images by pairing their sparse components. We show numerically that this algorithm works ...

2013

Query Optimization in Context of Pseudo Relevant Documents

Ashish Kishore Bindal

In conventional vector space model for information retrieval, query vector generation is imperfect for retrieval of precise documents which are de-sired by user. In this paper, we present a stochastic based approach for optimiz-ing query vector without use ...

2012

Compressed Sensing of Simultaneous Low-Rank and Joint-Sparse Matrices

Pierre Vandergheynst, Mohammad Golbabaee

In this paper we consider recovery of a high dimensional data matrix from a set of incomplete and noisy linear measurements. We introduce a new model which can efficiently restricts the degrees of freedom of data and, at the same time, is generic so that f ...

2012

Compressed Sensing of Simultaneous Low-Rank and Joint-Sparse Matrices

Pierre Vandergheynst, Mohammad Golbabaee

In this paper we consider the problem of recovering a high dimensional data matrix from a set of incomplete and noisy linear measurements. We introduce a new model that can efficiently restrict the degrees of freedom of the problem and is generic enough to ...

Institute of Electrical and Electronics Engineers2012

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