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Tuesday 29 May 2018, 11:30 at LPTENS, LPTENS library  STRLPTENSHE (Séminaire commun LPTENS/LPTHE)  hepth 



Abstract:  TBA 
Tuesday 29 May 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 



Abstract:  I will discuss the generalization to pforms of the Galileon idea: to construct the most general theory of an (abelian gauge invariant) pform with (strictly) second order field equations. Such theory have recently be fully classified for spacetime dimension strictly smaller than 12. The covariantization of these theories will also be discussed. 
Tuesday 29 May 2018, 17:15 at DPTPHYSENS, Jean Jaures (29 rue d'Ulm)  SEMPHYSENS (Colloquium du Département de Physique de l'ENS)  physics.bioph 



Abstract:  TBA 
Thursday 31 May 2018, 10:00 at IHP, 314  RENCTHEO (Rencontres Théoriciennes)  hepth 


Thursday 31 May 2018, 11:45 at IHP, 314  RENCTHEO (Rencontres Théoriciennes)  hepth 


Friday 1 June 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/197 )  COURS (Cours)  condmatqbio 



Abstract:  Artificial neural networks, introduced decades ago, are now key tools for automatic learning from data. This series of six lectures will focus on a few neural network architectures used in the context of unsupervised learning, that is, of unlabeled data. \par In particular we will focus on dimensional reduction, feature extraction, and representation building. We will see how statistical physics, in particular the techniques and concepts of random matrix theory and disordered systems, can be used to understand the properties of these algorithms and the phase transitions taking place in their operation. \par Special attention will be devoted to the socalled highdimensional inference setting, where the numbers of data samples and of defining parameters of the neural nets are comparable. The general principles will be illustrated on recent applications to data coming from neuroscience and genomics, highlighting the potentialities of unsupervised learning for biology. \par Some issues: \\  What is unsupervised learning? \\  Hebbian learning for principal component analysis: retardedlearning phase transition and prior information. \\  Bipartite neural nets and representations: autoencoders, restricted Boltzmann machines, Boltzmann machines. \\  Recurrent neural nets: from point to finitedimensional attractors, temporal sequences.  
Attachments: 
Monday 4 June 2018, 09:00 at
IPHT,
Amphi Claude Bloch, Bât. 774 ( https://indico.in2p3.fr/event/17044/ )  WORKCONF (Workshop or Conference)  physics 



Abstract:  The 23rd Claude Itzykson Conference, which will take place in the Bloch Amphitheater from June 4 to 6, 2018, is dedicated to our colleague and friend Cirano De Dominicis who was the head and a prominent member of our laboratory for many years. \\ \par The themes of the conference will cover the scientific interests of Cirano: \\ Quantum Systems, \\ Out of Equilibrium Statistical Physics, \\ Disordered Systems and Spin Glasses, \\ Interdisciplinary Systems. \\ \\ \\ The website of the conference is: https://indico.in2p3.fr/event/17044/ \\ \\ Organizing committee: Giulio Biroli, Edouard Brézin, Henri Orland and Laure Sauboy (secretary). \\ \\ Sponsors and benefactors: IPhT (CEA and CNRS), DRF, LabEx LMH. 
Tuesday 5 June 2018, 11:30 at LPTENS, LPTENS library  STRLPTENSHE (Séminaire commun LPTENS/LPTHE)  hepth 



Abstract:  TBA 
Tuesday 5 June 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 


Tuesday 5 June 2018, 16:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTHEP (Séminaire de physique des particules et de cosmologie)  hepph 


Friday 8 June 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/197 )  COURS (Cours)  condmatqbio 



Abstract:  Artificial neural networks, introduced decades ago, are now key tools for automatic learning from data. This series of six lectures will focus on a few neural network architectures used in the context of unsupervised learning, that is, of unlabeled data. \par In particular we will focus on dimensional reduction, feature extraction, and representation building. We will see how statistical physics, in particular the techniques and concepts of random matrix theory and disordered systems, can be used to understand the properties of these algorithms and the phase transitions taking place in their operation. \par Special attention will be devoted to the socalled highdimensional inference setting, where the numbers of data samples and of defining parameters of the neural nets are comparable. The general principles will be illustrated on recent applications to data coming from neuroscience and genomics, highlighting the potentialities of unsupervised learning for biology. \par Some issues: \\  What is unsupervised learning? \\  Hebbian learning for principal component analysis: retardedlearning phase transition and prior information. \\  Bipartite neural nets and representations: autoencoders, restricted Boltzmann machines, Boltzmann machines. \\  Recurrent neural nets: from point to finitedimensional attractors, temporal sequences.  
Attachments: 
Monday 11 June 2018, 11:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTPHM (Séminaire de physique mathématique)  mathph 


Monday 11 June 2018, 14:00 at
IHES,
Amphithéâtre Léon Motchane ( Cours de l'IHES )  MATHIHES (TBA)  hepth 



Abstract:  The gravitational waves detected by LIGO were produced in the final faze of the inward spiraling of two black holes before they collided to produce a more massive black hole. The experiment is entirely consistent with the so called Final State Conjecture of General Relativity according to which generic solutions of the Einstein vacuum equations can be described, asymptotically, by a finite number of Kerr solutions moving away from each other. Though the conjecture is so very easy to formulate and happens to be validated by both astrophysical observations as well as numerical experiments, it is far beyond our current mathematical understanding. In fact even the far simpler and fundamental question of the stability of one Kerr black hole remains wide open. In my lectures I will address the issue of stability as well as other aspects the mathematical theory of black holes such as rigidity of black holes and the problem of collapse. The rigidity conjecture asserts that all stationary solutions the Einstein vacuum equations must be Kerr black holes while the problem of collapse addresses the issue of how black holes form in the first place from regular initial conditions. Recent advances on all these problems were made possible by a remarkable combination of geometric and analytic techniques which I will try to outline in my lectures. 
Tuesday 12 June 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 



Abstract:  Scalartensor theories serve models for inflation and dark energy. Many efforts have been made recently for constructing the most general scalartensor theories with higherorder derivatives in their Lagrangian. Since higherderivative theories are typically associated with Ostrogradsky ghost which causes unbounded Hamiltonian, it is important to clarify how to evade it. In this talk, I will explain construction of healthy degenerate theories with higherorder derivatives which circumvent Ostrogradsky ghost. The method also allows us to construct ghostfree theories with derivatives higher than second order in Lagrangian. 
Tuesday 12 June 2018, 17:15 at DPTPHYSENS, Jean Jaures (29 rue d'Ulm)  SEMPHYSENS (Colloquium du Département de Physique de l'ENS)  physics.plasmph 



Abstract:  TBA 
Wednesday 13 June 2018, 14:00 at
IHES,
Amphithéâtre Léon Motchane ( Cours de l'IHES )  MATHIHES (TBA)  hepth 



Abstract:  The gravitational waves detected by LIGO were produced in the final faze of the inward spiraling of two black holes before they collided to produce a more massive black hole. The experiment is entirely consistent with the so called Final State Conjecture of General Relativity according to which generic solutions of the Einstein vacuum equations can be described, asymptotically, by a finite number of Kerr solutions moving away from each other. Though the conjecture is so very easy to formulate and happens to be validated by both astrophysical observations as well as numerical experiments, it is far beyond our current mathematical understanding. In fact even the far simpler and fundamental question of the stability of one Kerr black hole remains wide open. In my lectures I will address the issue of stability as well as other aspects the mathematical theory of black holes such as rigidity of black holes and the problem of collapse. The rigidity conjecture asserts that all stationary solutions the Einstein vacuum equations must be Kerr black holes while the problem of collapse addresses the issue of how black holes form in the first place from regular initial conditions. Recent advances on all these problems were made possible by a remarkable combination of geometric and analytic techniques which I will try to outline in my lectures. 
Friday 15 June 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/198 )  COURS (Cours)  astrophhepph 



Abstract:  (TBA)  
Attachments: 
Tuesday 19 June 2018, 11:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTGEN (Séminaire général du SPhT)  physics 


Tuesday 19 June 2018, 14:00 at
IHES,
Amphithéâtre Léon Motchane ( Cours de l'IHES )  MATHIHES (TBA)  hepth 



Abstract:  The gravitational waves detected by LIGO were produced in the final faze of the inward spiraling of two black holes before they collided to produce a more massive black hole. The experiment is entirely consistent with the so called Final State Conjecture of General Relativity according to which generic solutions of the Einstein vacuum equations can be described, asymptotically, by a finite number of Kerr solutions moving away from each other. Though the conjecture is so very easy to formulate and happens to be validated by both astrophysical observations as well as numerical experiments, it is far beyond our current mathematical understanding. In fact even the far simpler and fundamental question of the stability of one Kerr black hole remains wide open. In my lectures I will address the issue of stability as well as other aspects the mathematical theory of black holes such as rigidity of black holes and the problem of collapse. The rigidity conjecture asserts that all stationary solutions the Einstein vacuum equations must be Kerr black holes while the problem of collapse addresses the issue of how black holes form in the first place from regular initial conditions. Recent advances on all these problems were made possible by a remarkable combination of geometric and analytic techniques which I will try to outline in my lectures. 
Tuesday 19 June 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 


Friday 22 June 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/198 )  COURS (Cours)  astrophhepph 



Abstract:  (TBA)  
Attachments: 
Friday 22 June 2018, 14:00 at
IHES,
Amphithéâtre Léon Motchane ( Cours de l'IHES )  MATHIHES (TBA)  hepth 



Abstract:  The gravitational waves detected by LIGO were produced in the final faze of the inward spiraling of two black holes before they collided to produce a more massive black hole. The experiment is entirely consistent with the so called Final State Conjecture of General Relativity according to which generic solutions of the Einstein vacuum equations can be described, asymptotically, by a finite number of Kerr solutions moving away from each other. Though the conjecture is so very easy to formulate and happens to be validated by both astrophysical observations as well as numerical experiments, it is far beyond our current mathematical understanding. In fact even the far simpler and fundamental question of the stability of one Kerr black hole remains wide open. In my lectures I will address the issue of stability as well as other aspects the mathematical theory of black holes such as rigidity of black holes and the problem of collapse. The rigidity conjecture asserts that all stationary solutions the Einstein vacuum equations must be Kerr black holes while the problem of collapse addresses the issue of how black holes form in the first place from regular initial conditions. Recent advances on all these problems were made possible by a remarkable combination of geometric and analytic techniques which I will try to outline in my lectures. 
Tuesday 26 June 2018, 11:30 at LPTENS, LPTENS library  STRLPTENSHE (Séminaire commun LPTENS/LPTHE)  hepth 



Abstract:  TBA 
Tuesday 26 June 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 


Tuesday 26 June 2018, 17:15 at DPTPHYSENS, Jean Jaures (29 rue d'Ulm)  SEMPHYSENS (Colloquium du Département de Physique de l'ENS)  physics.fludyn 



Abstract:  TBA 
Friday 29 June 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/198 )  COURS (Cours)  astrophhepph 



Abstract:  (TBA)  
Attachments: 
Tuesday 3 July 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 



Abstract:  Turbulence is an ubiquitous phenomenon in natural and industrial fluid flows. Yet, it still lacks a satisfactory theoretical description. One of the main open issues is to calculate the statistical properties of the turbulent steady state, and in particular what is generically called intermittency effects, starting from the fundamental description of the fluid dynamics provided by NavierStokes equation. In this presentation, I will focus on isotropic and homogeneous turbulence in threedimensional incompressible flows. In the first part, I will give an introduction on the basic phenomenology of turbulence, and show what are the typical manifestations of intermittency. In the second part, I will explain how one can derive exact asymptotic (i.e. at large wave numbers) properties of the correlation functions in the turbulent state, using a fieldtheoretic approach, based on the NonPerturbative Renormalisation Group, and compare them to numerical simulations and experiments. 
Friday 6 July 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/198 )  COURS (Cours)  astrophhepph 



Abstract:  (TBA)  
Attachments: 
Tuesday 10 July 2018, 14:00 at APC, 483 A  Malevitch  APCTH (Seminar of the theory group of APC)  hepth 


Friday 13 July 2018, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=fr/node/198 )  COURS (Cours)  astrophhepph 



Abstract:  (TBA)  
Attachments: 

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