Publications associées à Singularité gravitationnelle

Resolving the vicinity of supermassive black holes with gravitational microlensing

Upcoming wide-field surveys will discover thousands of new strongly lensed quasars which will be monitored with unprecedented cadence by the Legacy Survey of Space and Time (LSST). Many of these quasars will undergo caustic-crossing events over the 10-yr L ...

Oxford Univ Press2024

Experimental observation of topological transition in linear and nonlinear parametric oscillators

Romain Christophe Rémy Fleury, Benjamin Apffel

Parametric oscillators are examples of externally driven systems that can exhibit two stable states with opposite phase depending on the initial conditions. In this work, we propose to study what happens when the external forcing is perturbed by a continuo ...

2024

Arithmetic and geometric deformations of threefolds

Stefano Filipazzi, Fabio Bernasconi

We show that mixed-characteristic and equicharacteristic small deformations of 3-dimensional canonical (resp., terminal) singularities with perfect residue field of characteristic p>5 are canonical (resp., terminal). We discuss applications to arithmetic a ...

Wiley2023

Propagation of singularities for the stochastic wave equation

Cheuk Yin Lee

We study the existence and propagation of singularities of the solution to a one-dimensional linear stochastic wave equation driven by an additive Gaussian noise that is white in time and colored in space. Our approach is based on a simultaneous law of the ...

ELSEVIER2022

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: N-body mock challenge for galaxy clustering measurements

Cheng Zhao

We develop a series of N-body data challenges, functional to the final analysis of the extended Baryon Oscillation Spectroscopic Survey (eBOSS) Data Release 16 (DR16) galaxy sample. The challenges are primarily based on high-fidelity catalogues constructed ...

OXFORD UNIV PRESS2021

Distributed Learning in Non-Convex Environments-Part II: Polynomial Escape From Saddle-Points

Ali H. Sayed, Stefan Vlaski

The diffusion strategy for distributed learning from streaming data employs local stochastic gradient updates along with exchange of iterates over neighborhoods. In Part I [3] of this work we established that agents cluster around a network centroid and pr ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2021

The completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: N-body mock challenge for the quasar sample

Jean-Paul Richard Kneib

The growth rate and expansion history of the Universe can be measured from large galaxy redshift surveys using the Alcock-Paczynski effect. We validate the Redshift Space Distortion models used in the final analysis of the Sloan Digital Sky Survey (SDSS) e ...

OXFORD UNIV PRESS2020

Core Cosmology Library: Precision Cosmological Predictions for LSST

David Atienza Alonso, Jonathan Andrew Blazek

The Core Cosmology Library (CCL) provides routines to compute basic cosmological observables to a high degree of accuracy, which have been verified with an extensive suite of validation tests. Predictions are provided for many cosmological quantities, incl ...

IOP PUBLISHING LTD2019

Toward an Internally Consistent Astronomical Distance Scale

Frédéric Courbin

Accurate astronomical distance determination is crucial for all fields in astrophysics, from Galactic to cosmological scales. Despite, or perhaps because of, significant efforts to determine accurate distances, using a wide range of methods, tracers, and t ...

Springer2017

Guaranteeing Input Tracking For Constrained Systems: Theory and Application to Demand Response

Colin Neil Jones, Tomasz Tadeusz Gorecki, Georgios Stathopoulos, Altug Bitlislioglu

A method for certifying exact input trackability for constrained discrete time linear systems is introduced in this paper. A signal is assumed to be drawn from a reference set and the system must track this signal with a linear combination of its inputs. U ...

2015

Turnpike and dissipativity properties in dynamic real-time optimization and economic MPC

Dominique Bonvin, Colin Neil Jones, Timm Faulwasser, Milan Korda

We investigate the turnpike and dissipativity properties of continuous-time optimal control problems. These properties play a key role in the analysis and design of schemes for dynamic real-time optimization and economic model predictive control. We show i ...

2014

The local Callan-Symanzik equation: structure and applications

Riccardo Rattazzi, Boaz Keren Zur, Lorenzo Vitale, Florent Baume

The local Callan-Symanzik equation describes the response of a quantum field theory to local scale transformations in the presence of background sources. The consistency conditions associated with this anomalous equation imply non-trivial relations among t ...

Springer Nature2014

Influence of physical galaxy properties on Ly alpha escape in star-forming galaxies

Jean-Paul Richard Kneib, Hakim Atek

Context. Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Ly alpha) is of particular interest because it gives access to the measurement of cosmological quantities such as the ...

EDP Sciences2014

Inflation, leptogenesis, and Yukawa quasiunification within a supersymmetric left-right model

Roberta Armillis

A simple extension of the minimal left-right symmetric supersymmetric grand unified theory model is constructed by adding two pairs of superfields. This naturally violates the partial Yukawa unification predicted by the minimal model. After including super ...

American Physical Society2014

Initial or final values for semiclassical evolutions in the Weyl–Wigner representation

David Eduardo Zambrano Ramirez

Initial value representations are constructed to avoid the search for trajectories that are only defined in semiclassical approximations by their boundary conditions. We show how to incorporate these procedures within the full Weyl representation, so that ...

2013

CMB photons shedding light on dark matter

Julien Lesgourgues, Benjamin Audren, Gaëlle Giesen

The annihilation or decay of Dark Matter (DM) particles could affect the thermal history of the universe and leave an observable signature in Cosmic Microwave Background (CMB) anisotropies. We update constraints on the annihilation rate of DM particles in ...

Iop Publishing Ltd2012

A Framework for Numerical Simulations of Structure Formation

Claude Becker

In the absence of a full analytical treatment of nonlinear structure formation in the universe, numerical simulations provide the critical link between the properties of the underlying model and the features of the observed structures. Currently N-body sim ...

EPFL2011

Baryon asymmetry of the Universe without Boltzmann or Kadanoff-Baym equations

Mikhail Chapochnikov, Jean-Sébastien Gagnon

We present a formalism that allows the computation of the baryon asymmetry of the Universe, from the first principles of statistical physics and quantum field theory, that is applicable to certain types of physics beyond the standard model (such as the neu ...

American Physical Society2011

Analytical Footprints: Compact Representation of Elementary Singularities in Wavelet Bases

Michaël Unser, Dimitri Nestor Alice Van De Ville, Thierry Blu

We introduce a family of elementary singularities that are point-Holder alpha-regular. These singularities are self-similar and are the Green functions of fractional derivative operators; i.e., by suitable fractional differentiation, one retrieves a Dirac ...

Institute of Electrical and Electronics Engineers2010

Phase transitions in full counting statistics for periodic pumping

Dmitri Ivanov

We discuss the problem of full counting statistics for periodic pumping. The probability generating function is usually defined on a circle of the "physical" values of the counting parameter, with its periodicity corresponding to charge quantization. The e ...

2010