The SEMPARIS seminar webserver hosts annoucements of all seminars taking place in Paris area, in all topics of physics, mathematics and computer science. It allows registered users to receive a selection of announcements by email on a daily or weekly basis, and offers the possibility to archive PDF or Powerpoint files, making it available to the scientific community. [ More information ]
Upcoming Seminars at LPTHE  
[ scheduler view ] 
Monday 6 February 2023, 15:00 at LPTHE, LPTHE Library  SEMLPTHE (Séminaire du LPTHE)  condmat.statmech 



Abstract:  Quantum circuits are discretetime models for manybody dynamics. They have a minimal amount of structure, making them a useful starting point for studying the outofequilibrium evolution of entanglement and correlations. Circuits are also a natural setting for defining broader classes of dynamics that involve measurement and feedback operations. In this talk I will define what random quantum circuits are, sketch one of the basic structures allowing analytical calculations, and describe an entanglement phase transition induced by repeated quantum measurement. 
Thursday 9 February 2023, 14:00 at LPENS, L378 / L380 (24 Rue Lhomond)  LPTENSHE (Séminaire commun LPTENSLPTHE)  hepth 



Abstract:  Studying the lightcone limit of CFT correlation functions has been one of the leading methods to analyse the crossing symmetry analytically. In a CFT with a twist gap, a 4point function of identical scalars leads to interesting predictions of the existence of families of infinite doubletwist operators and their OPE data. However a complete knowledge of the CFT spectrum is only accessible from bootstrapping correlators with nonidentical external operators with arbitrary spin, which is in general a difficult problem. Alternatively one can look at correlators of more than four identical scalars which, via OPE, captures the same information. I will discuss how to systematically set up the lightcone bootstrap for 5 and 6point functions of identical scalars. 
Thursday 16 February 2023, 10:00 at IHP, 314  RENCTHEO (Rencontres Théoriciennes)  hepth 



Abstract:  Recent advances indicate that a 3d gravity partition function may be dual not to a single CFT but to an average over an ensemble of CFTs. In my talk I will discuss an explicit ensemble of CFTs deriving from classical binary errorcorrecting codes. Such codes have been studied and classified by discrete mathematicians for decades and give rise to chiral CFTs via a lattice construction. By this construction, the average over the ensemble of errorcorrecting codes translates to an average over CFTs with enhanced SU(2)^c symmetry. The averaged partition function shows some gravitational features and matches with a Poincaré sum corresponding to a sum over bulk geometries. 
Tuesday 21 February 2023, 14:00 at LPENS, Ferdinand Berthier (U207), Bâtiment Jaurès (29 Rue d'Ulm)  LPTENSHE (Séminaire commun LPTENSLPTHE)  hepth 



Abstract:  The amplitude/Wilson loop correspondence identifies planar N=4 superYangMills amplitudes with certain null polygonal Wilson loops at all the values of the coupling. At strong coupling the Wilson loop was computed by Alday & Maldacena in terms of the area of a minimal surface in AdS5. To do so they developed a `Y system' for computing the amplitude. This talk reinterprets their construction as provding the underlying twistor space for a hyperKahler structure on the corresponding space of kinematic data. This geometry encodes the amplitude in terms of solutions to well known integrable differential equations. An as yet unfulfilled aspiration is to extend these ideas beyond strong coupling using formal similarities with other approaches. 
Thursday 16 March 2023, 11:00 at LPTHE, bibliothèque du LPTHE, tour 1314, 4eme étage  SEMDARBOUX (Séminaire Darboux  physique théorique et mathématiques)  hepth 


Thursday 23 March 2023, 14:00 at LPTHE, LPTHE's library, towers 1314, 4th floor  TQM (Theory of quantum matter)  condmat 



Abstract:  TBA 
Thursday 6 April 2023, 14:00 at LPTHE, INSP Jussieu towers 2223 room 317???  TQM (Theory of quantum matter)  condmat 



Abstract:  TBA 
Thursday 13 April 2023, 11:00 at LPTHE, bibliothèque du LPTHE, tour 1314, 4eme étage  SEMDARBOUX (Séminaire Darboux  physique théorique et mathématiques)  hepth 


Thursday 11 May 2023, 14:00 at LPTHE, INSP Jussieu towers 2223 room 317???  TQM (Theory of quantum matter)  condmat 



Abstract:  TBA 
Thursday 1 June 2023, 11:00 at LPTHE, bibliothèque du LPTHE, tour 1314, 4eme étage  SEMDARBOUX (Séminaire Darboux  physique théorique et mathématiques)  hepthmath.AG 


Thursday 15 June 2023, 11:00 at LPTHE, bibliothèque du LPTHE, tour 1314, 4eme étage  SEMDARBOUX (Séminaire Darboux  physique théorique et mathématiques)  hepth 



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