Concept

Covariance générale

Publications associées (35)

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A generalization of the Solis-Wets method

In this paper we focus on the application of global stochastic optimization methods to extremum estimators. We propose a general stochastic method the master method which includes several stochastic optimization algorithms as a particular case. The propose ...

Elsevier2012

Models of non-relativistic quantum gravity: the good, the bad and the healthy

Sergey Sibiryakov, Diego Blas Temino

Horava's proposal for non-relativistic quantum gravity introduces a preferred time foliation of space-time which violates the local Lorentz invariance. The foliation is encoded in a dynamical scalar field which we call 'khronon'. The dynamics of the khrono ...

2011

Modeling dimensionally-heterogeneous problems: analysis, approximation and applications

Alfio Quarteroni, Marco Discacciati

In the present work a general theoretical framework for coupled dimensionally-heterogeneous partial differential equations is developed. This is done by recasting the variational formulation in terms of coupling interface variables. In such a general setti ...

Springer-Verlag2011

Modeling and Simulation of the Operation of a Rotary Magnetic Refrigerator

Didier Albert Simon Vuarnoz, Cyrill Gonin

Magnetic refrigeration is a new environmentally benign technology and a promising alternative to conventional vapor-cycle refrigeration. Among these technologies the household refrigerator without a freezing compartment shows very good prospects for a succ ...

2011

Symmetry Reduced Dynamics of Charged Molecular Strands

Tudor Ratiu, François Gay-Balmaz

The equations of motion are derived for the dynamical folding of charged molecular strands (such as DNA) modeled as flexible continuous filamentary distributions of interacting rigid charge conformations. The new feature is that these equations are nonloca ...

Springer-Verlag2010

Composing Relaxed Transactions

Rachid Guerraoui, Vincent Gramoli, Mihai Letia

As the classical transactional abstraction is sometimes considered too restrictive in leveraging parallelism, a lot of work has been devoted to devising relaxed transactional models with the goal of improving concurrency. Nevertheless, the quest for improv ...

2010

4d Lorentzian Holst action with topological terms

Danilo Jimenez Rezende

We study the Hamiltonian formulation of the general first order action of general relativity compatible with local Lorentz invariance and background independence. The most general simplectic structure (compatible with diffeomorphism invariance and local Lo ...

2009

Galileon as a local modification of gravity

Riccardo Rattazzi

In the Dvali-Gabadadze-Porrati (DGP) model, the "self-accelerating" solution is plagued by a ghost instability, which makes the solution untenable. This fact, as well as all interesting departures from general relativity (GR), are fully captured by a four- ...

2009

Variational Principles For Spin Systems And The Kirchhoff Rod

Tudor Ratiu, François Gay-Balmaz

We obtain the affine Euler-Poincare equations by standard Lagrangian reduction and deduce the associated Clebsch-constrained variational principle. These results are illustrated in deriving the equations of motion for continuum spin systems and Kirchhoff's ...

2009

Modeling and simulation of the operation of a rotary magnetic refrigerator

Didier Albert Simon Vuarnoz, Cyrill Gonin

Magnetic refrigeration is a new environmentally benign technology and a promising alternative to conventional vapor-cycle refrigeration. The household refrigerator without a freezing compartment shows very good prospects for a successful application. This ...

2009