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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. 
Wednesday 13 June 2018, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 



Abstract:  (TBA) 
Thursday 14 June 2018, 11:30 at
IPN,
Bâtiment 100, Salle A015 ( $ $ )  IPNTHEO (Séminaire du groupe de physique théorique de l'IPN Orsay)  nuclth 



Abstract:  1) The influence of a strong laser electromagnetic field on the alphadecay rate is ingestigated by using the Hennenberger frame of reference [1] within adiabadic and static limits. The penetrability of the Coulomb barrier becomes anisotropic for intensities corresponding to $D\sim1$, where $D$ is an adimensional parameter proportional to the square root of the intensity. As a consequence, we predict that two counters placed at zero and 90 degrees will indicate different numbers. 2) Alpha clusters are born in nuclei at low densities, the wave function being a Gaussian peaked on the nuclear surface and therefore corresponding to a local pocketlike potential. The alphaparticle formation probability reaches the largest value in the ”alphadecay island” above $^{100}$Sn for N$\sim$Z nuclei [2] and therefore the clusters can be easier detected. We show that the shape of the alphacluster can be determined by exciting it to the first resonant state inside the pocketlike potential, by using a quasimonochromatic gammabeam produced at the ELINP facility. The position and width of this ”alphalike pygmy” resonant state [3] can be predicted by using the alphadecay systematics to ground and excited states [4]. \\ [1] D.S. Delion and S. Ghinescu, GeigerNuttall law for nuclei in strong electromagnetic fields, Phys. Rev. Lett. 119, 202501 (2017).\newline [2] V.V. Baran and D.S. Delion, Protonneutron versus alphalike correlations above $^{100}$Sn, Phys. Rev. C 94, 034319 (2016).\newline [3] V.V. Baran and D.S. Delion, Alphalike resonances in nuclei, J. Phys. G 45, 035106 (2018).\newline [4] D.S. Delion, Universal decay rule for reduced widths, Phys. Rev. C 80, 024310 (2009).  
Attachments: 
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:  Dark matter constitutes about 26\% of the present matterenergy content of the Universe (84\% of the matteronly content) and is one of the fundamental ingredients that shape the evolution of galaxies and the Universe. Surprisingly enough, the nature of dark matter is still unknown, and unveiling this mystery stands out as one of the most pressing issues in cosmology and particle physics. \par The course will present a basic overview of the state of the art in dark matter physics, mostly focussing on the phenomenology rather than on the many models proposed by particle theorists to explain it. \\ \par Plan of the lectures: \\ 1) Introduction, proofs of existence, and basic properties. Possible alternatives to particle dark matter and their status. \\ 2) Mechanisms of production in the early Universe: thermal freezeout (in particular), freezein, asymmetric dark matter... \\ 3) Direct detection via nuclear recoils. \\ 4) Indirect detection with cosmic rays: charged particles, gamma rays (prompt and secondary), neutrinos. \\ 5) Collider searches (and possible complementarity of the searches).  
Attachments: 
Friday 15 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, 16:30 at LPTENS, LPTENS library  STRLPTENSHE (Séminaire commun LPTENS/LPTHE)  hepth 



Abstract:  TBA 
Monday 18 June 2018, 11:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTPHM (Séminaire de physique mathématique)  mathph 



Abstract:  In this seminar, we will discuss affine Gaudin models, which are integrable systems associated with KacMoody algebras of affine type. \par First, we will review how these models can be classically interpreted as integrable field theories in two dimensions. Conversely, we shall see that integrable sigmamodels, which are typical examples of such theories, are realisations of classical affine Gaudin models. \par In a second part, we will discuss results and conjectures about quantum affine Gaudin models, concerning the construction of higher degree quantum Hamiltonians and their diagonalisation through the Bethe ansatz. Finally, we will explore the possible relation of these results with the ODE/IM correspondence, using the language of affine opers. 
Tuesday 19 June 2018, 11:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTGEN (Séminaire général du SPhT)  physics 


Tuesday 19 June 2018, 11:00 at IHES, Amphithéâtre Léon Motchane  MATHIHES (TBA)  hepth 



Abstract:  The notion of Cohomological Hall algebra (COHA) was introduced in our joint paper with Maxim Kontsevich 10 years ago. It can be thought of as a mathematical incarnation of the notion of BPS algebra envisioned by physicists Harvey and Moore in the 90's. Mathematically, COHA is an associative algebra structure on the cohomology of the moduli stack of objects of a 3dimensional CalabiYau category with coefficients in a certain constructible sheaf. Interesting categories can be of geometric or algebraic origin (sheaves on CalabiYau 3folds, quivers with potential, etc.). In the talk I plan to discuss actions of COHA on the cohomology of certain instanton moduli spaces (spiked instantons of Nekrasov). This gives a relationship of COHA with affine Yangians and more recent "vertex algebras at the corner" introduced by Gaiotto and Rapcak. 
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:  Dark matter constitutes about 26\% of the present matterenergy content of the Universe (84\% of the matteronly content) and is one of the fundamental ingredients that shape the evolution of galaxies and the Universe. Surprisingly enough, the nature of dark matter is still unknown, and unveiling this mystery stands out as one of the most pressing issues in cosmology and particle physics. \par The course will present a basic overview of the state of the art in dark matter physics, mostly focussing on the phenomenology rather than on the many models proposed by particle theorists to explain it. \\ \par Plan of the lectures: \\ 1) Introduction, proofs of existence, and basic properties. Possible alternatives to particle dark matter and their status. \\ 2) Mechanisms of production in the early Universe: thermal freezeout (in particular), freezein, asymmetric dark matter... \\ 3) Direct detection via nuclear recoils. \\ 4) Indirect detection with cosmic rays: charged particles, gamma rays (prompt and secondary), neutrinos. \\ 5) Collider searches (and possible complementarity of the searches).  
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. 
Monday 25 June 2018, 10:45 at LPTMC, Jussieu, room 523, 5th floor, tower 1312  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 


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



Abstract:  For the current central values of the Higgs boson and top quark masses, the standard model Higgs potential develops an instability at a scale of the order of $10^{11}\,$GeV. We show that cosmological signatures of such instability could be dark matter in the form of primordial black holes and the production of gravitational waves, sourced by Higgs fluctuations during inflation. The existence of dark matter might not require physics beyond the standard model, and this hypothesis may find its confirmation through the detection of gravitational waves. 
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:  Dark matter constitutes about 26\% of the present matterenergy content of the Universe (84\% of the matteronly content) and is one of the fundamental ingredients that shape the evolution of galaxies and the Universe. Surprisingly enough, the nature of dark matter is still unknown, and unveiling this mystery stands out as one of the most pressing issues in cosmology and particle physics. \par The course will present a basic overview of the state of the art in dark matter physics, mostly focussing on the phenomenology rather than on the many models proposed by particle theorists to explain it. \\ \par Plan of the lectures: \\ 1) Introduction, proofs of existence, and basic properties. Possible alternatives to particle dark matter and their status. \\ 2) Mechanisms of production in the early Universe: thermal freezeout (in particular), freezein, asymmetric dark matter... \\ 3) Direct detection via nuclear recoils. \\ 4) Indirect detection with cosmic rays: charged particles, gamma rays (prompt and secondary), neutrinos. \\ 5) Collider searches (and possible complementarity of the searches).  
Attachments: 
Monday 2 July 2018, 10:45 at LPTMC, Jussieu, room 523, 5th floor, tower 1312  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 



Abstract:  TBA 
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. 
Wednesday 4 July 2018, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 



Abstract:  (TBA) 
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:  Dark matter constitutes about 26\% of the present matterenergy content of the Universe (84\% of the matteronly content) and is one of the fundamental ingredients that shape the evolution of galaxies and the Universe. Surprisingly enough, the nature of dark matter is still unknown, and unveiling this mystery stands out as one of the most pressing issues in cosmology and particle physics. \par The course will present a basic overview of the state of the art in dark matter physics, mostly focussing on the phenomenology rather than on the many models proposed by particle theorists to explain it. \\ \par Plan of the lectures: \\ 1) Introduction, proofs of existence, and basic properties. Possible alternatives to particle dark matter and their status. \\ 2) Mechanisms of production in the early Universe: thermal freezeout (in particular), freezein, asymmetric dark matter... \\ 3) Direct detection via nuclear recoils. \\ 4) Indirect detection with cosmic rays: charged particles, gamma rays (prompt and secondary), neutrinos. \\ 5) Collider searches (and possible complementarity of the searches).  
Attachments: 
Monday 9 July 2018, 10:45 at LPTMC, Jussieu, room 523, 5th floor, tower 1312  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 


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:  Dark matter constitutes about 26\% of the present matterenergy content of the Universe (84\% of the matteronly content) and is one of the fundamental ingredients that shape the evolution of galaxies and the Universe. Surprisingly enough, the nature of dark matter is still unknown, and unveiling this mystery stands out as one of the most pressing issues in cosmology and particle physics. \par The course will present a basic overview of the state of the art in dark matter physics, mostly focussing on the phenomenology rather than on the many models proposed by particle theorists to explain it. \\ \par Plan of the lectures: \\ 1) Introduction, proofs of existence, and basic properties. Possible alternatives to particle dark matter and their status. \\ 2) Mechanisms of production in the early Universe: thermal freezeout (in particular), freezein, asymmetric dark matter... \\ 3) Direct detection via nuclear recoils. \\ 4) Indirect detection with cosmic rays: charged particles, gamma rays (prompt and secondary), neutrinos. \\ 5) Collider searches (and possible complementarity of the searches).  
Attachments: 
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