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Wednesday 9 October 2019, 12:00 at LPENS, Conf IV  FORUMENS (Forum de Physique Statistique @ ENS)  condmat.statmech 


Wednesday 9 October 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 


Thursday 10 October 2019, 11:00 at LPTHE, bibliothèque du LPTHE, tour 1314, 4eme étage  SEMDARBOUX (Séminaire Darboux  physique théorique et mathématiques)  math.NT 


Friday 11 October 2019, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=en/node/226 )  COURS (Cours)  hepthmathphquantph 



Abstract:  Paraphrasing Alexander Polyakov, ``Conformal Field Theory is a way to learn about elementary particles by studying boiling water''. There is a technical statement behind this joke: Euclidean Conformal Field Theory, under certain conditions, can be rotated to the Lorentzian signature, and vice versa. This means that even statistical physicists studying finitetemperature phase transitions on a lattice should learn about the Minkowski space! The goal of this course will be to explain various classical and recent results pertaining to this somewhat surprising conclusion. \\ \\ Plan of the course: \\  Elementary introduction to Euclidean CFT in $d>2$ dimensions; \\  The OsterwalderSchrader theorem about the Wick rotation of general reflectionpositive Euclidean Quantum Field Theories, and its limitations; \\  The LuescherMack theorem about continuation of CFT correlation functions to the Lorentzian cylinder, and its limitations; \\  Recent results about the analytic structure of Lorentzian CFT correlators.  
Attachments: 
Monday 14 October 2019, 10:45 at LPTMC, campus Jussieu, tower 1312, 5th floor, room 523  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 



Abstract:  The most remarkable feature of the socalled "topological crystals" is the presence of states flowing at their edge that are robust against disorder. A beautiful mathematical theory allows to predict the properties of such states directly from the topological invariants (e.g. the Chern numbers) of the bulk bands. Given the great success of this theory in terms of theoretical impact and technological advance, in recent years much effort has been put to make the extension from the field electronics to other fields[1] and from crystals to various noncrystaline systems such as quasicrystals and amorphous materials. In this talk I will show how deal with continuous systems governed by linear Maxwell's equations[2]. Even though bands Chern numbers cannot be defined and optical materials are nontopological, we discover that interface Chern numbers can always be defined by means of the theory of spectral flows[3]. These invariants correctly describe chiral modes as we verified numerically on interfaces between different gyrotropic materials. [1] S. Raghu and F. D. M. Haldane, Phys. Rev. A78, 033834 (2008). [2] M. G. Silveirinha, Phys. Rev. B92, 125153 (2015). [3] M. Marciani and P. Delplace, arXiv:1906.09057 (2019). 
Monday 14 October 2019, 14:00 at LPTM, 4.13 St Martin II  SOUTENTH (Soutenance de thèse)  quantph 



Abstract:  La théorie de la mesure, basée sur la mesure projective, constitue un aspect fondamental de la mécanique quantique. La mesure faible diffère de la mesure projective traditionnelle sur laquelle les axiomes élémentaires de la physique quantique sont bâtis. Bien que définie dans le cadre de la théorie quantique standard, les mesures faibles sont encore mal comprises. Le travail de thèse s'inscrit dans une large démarche qui vise à comprendre les implications conceptuelles et pratiques d'une telle mesure dans le cadre de la théorie quantique. Le chapitre 1 est une introduction détaillée à la mesure faible et à la valeur faible. Ensuite, nous étudierons les "trajectoires faibles" dans un interféromètre à fentes d'Young. Nous abordons au chapitre 3 les implications de l'annulation d'une valeur faible au regard de l'apparition de trajectoires faibles dans des interféromètres de MachZender imbriqués. Enfin, le chapitre 4 traite des critiques théoriques et expérimentales présentes dans la littérature concernant l'effet du Chat du Cheshire quantique qui est défini dans le cadre de mesures faibles. 
Monday 14 October 2019, 14:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTSTA (Séminaire de Physique Statistique, CEA/Saclay)  condmat 


Tuesday 15 October 2019, 14:00 at APC, 646A  Mondrian  APCTH (Seminar of the theory group of APC)  grqc 


Tuesday 15 October 2019, 16:30 at LPTM, 4.13 St Martin II  SEMEXCEP (Séminaire exceptionel)  physics.fludyn 



Abstract:  Yves Couder and Emmanuel Fort discovered that droplets walking on a vibrating fluid bath exhibit several features previously thought to be exclusive to the microscopic, quantum realm. These walking droplets propel themselves by virtue of a resonant interaction with their own wave field, and so represent the first macroscopic realization of a pilotwave system of the form proposed for microscopic quantum dynamics by Louis de Broglie in the 1920s. New experimental and theoretical results allow us to rationalize the emergence of quantumlike behavior in this hydrodynamic pilotwave system in a number of settings, and explore its potential and limitations as a quantum analog. 
Wednesday 16 October 2019, 12:00 at LPENS, Conf IV  FORUMENS (Forum de Physique Statistique @ ENS)  condmat.statmech 


Wednesday 16 October 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 


Thursday 17 October 2019, 11:40 at IHP, 314  RENCTHEO (Rencontres Théoriciennes)  hepth 


Thursday 17 October 2019, 14:00 at LPTMC, campus Jussieu, tower 1312, 5th floor, room 523  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 


Friday 18 October 2019, 10:00 at
IPHT,
Salle Claude Itzykson, Bât. 774 ( https://courses.ipht.cnrs.fr/?q=en/node/226 )  COURS (Cours)  hepthmathphquantph 



Abstract:  Paraphrasing Alexander Polyakov, ``Conformal Field Theory is a way to learn about elementary particles by studying boiling water''. There is a technical statement behind this joke: Euclidean Conformal Field Theory, under certain conditions, can be rotated to the Lorentzian signature, and vice versa. This means that even statistical physicists studying finitetemperature phase transitions on a lattice should learn about the Minkowski space! The goal of this course will be to explain various classical and recent results pertaining to this somewhat surprising conclusion. \\ \\ Plan of the course: \\  Elementary introduction to Euclidean CFT in $d>2$ dimensions; \\  The OsterwalderSchrader theorem about the Wick rotation of general reflectionpositive Euclidean Quantum Field Theories, and its limitations; \\  The LuescherMack theorem about continuation of CFT correlation functions to the Lorentzian cylinder, and its limitations; \\  Recent results about the analytic structure of Lorentzian CFT correlators.  
Attachments: 
Wednesday 23 October 2019, 14:00 at
IPN,
Bâtiment 100, Salle A015 ( $ $ )  IPNTHEO (Séminaire du groupe de physique théorique de l'IPN Orsay)  nuclth 



Abstract:  The interplay between the singleparticle states and the collective modes has been one of the central subjects of nuclear physics since the very beginning. If the singleparticle aspect is too strong, for instance, with a large gap between relevant orbits, it suppresses the collective mode. Thus, the singleparticle states and the collective modes have been considered to counteract each other, and the former behaves as a resistance against the latter. However, an opposing idea has arisen recently. The nuclear force is characterized by components driving a given collective mode, like the quadrupole interaction for the ellipsoidal shape and, in addition, by the monopole component that can reduce the resistance against collective modes. The energies of singleparticle orbits can thus be optimized for a given mode with favorable configurations. In fact, the monopole components of the central and tensor forces show strong orbital dependences, and can shift singleparticle energies effectively depending on the configurations of other nucleons. This mechanism can be interpreted as a quantum selforganization, and is consistent with the general selforganization concept. Its effect can be seen in the quantum phase transition of Zr isotopes [1], and more generally in the shape evolution in Sm isotopes as well as the band structure of $^{154}$Sm. The stateoftheart Monte Carlo Shell Model calculations with reasonable interactions produce properties of these nuclei in good agreement with experiments. The monopolecontrolled optimization is shown to be essential: if it is switched off, this good agreement disappears. One of the striking results is that contrary to the traditional idea, side bands of strongly deformed nuclei may not be beta or gamma vibration of the ellipsoidal shape, but can be consequences of manybody correlations due to nuclear forces, beyond the liquid drop model. A textbook example of $^{166}$Er shows that its key properties are reproduced by the shellmodel solution obtained around a triaxial minimum with strong gammainstability, including the relatively strong $0^+_1$, $2^+_2$ E2 excitation. Prospects over heavy nuclei and fission processes and possible experimental challenges will be discussed.\newline [1] T. Otsuka, Y. Tsunoda, et al., arXiv: 1907.10759 [nuclth].  
Attachments: 
Friday 25 October 2019, 11:00 at APC, TBA  APCCOLLOQUIUM (Colloquium de l'APC)  astroph 


Monday 4 November 2019, 14:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTSTA (Séminaire de Physique Statistique, CEA/Saclay)  condmat 


Tuesday 5 November 2019, 14:00 at APC, 646A  Mondrian  APCTH (Seminar of the theory group of APC)  grqc 


Wednesday 6 November 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 



Abstract:  (TBA) 
Friday 8 November 2019, 11:00 at APC, 366A  APCCOLLOQUIUM (Colloquium de l'APC)  astroph 



Abstract:  TBA 
Friday 8 November 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 


Tuesday 12 November 2019, 11:00 at CPHT, Salle Louis Michel, CPHT, Ecole Polytechnique  SEMCPHT (Séminaire du CPHT)  hepth 


Tuesday 12 November 2019, 14:00 at APC, 646A  Mondrian  APCTH (Seminar of the theory group of APC)  grqc 


Wednesday 13 November 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 


Monday 18 November 2019, 10:45 at LPTMC, campus Jussieu, tower 1312, 5th floor, room 523  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 


Monday 18 November 2019, 14:00 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTSTA (Séminaire de Physique Statistique, CEA/Saclay)  condmat 


Tuesday 19 November 2019, 11:30 at LPTHE, LPTHE library  STRLPTENSHE (Séminaire commun LPTENS/LPTHE)  hepth 


Tuesday 19 November 2019, 14:00 at APC, 646A  Mondrian  APCTH (Seminar of the theory group of APC)  grqc 


Wednesday 20 November 2019, 14:15 at IPHT, Salle Claude Itzykson, Bât. 774  IPHTMAT (Séminaire de matrices, cordes et géométries aléatoires)  hepth 


Monday 25 November 2019, 10:45 at LPTMC, Jussieu, tower 1312, room 523  SEMLPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée)  condmat.meshall 



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