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Upcoming Seminars [Next 30 ]
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Monday 19 March 2018, 10:30 at IHES, Amphithéâtre Léon Motchane MATH-IHES (TBA) hep-th
Vladimir Sokolov ( Landau Institute for Theoretical Physics & IHES ) TBA

Monday 19 March 2018, 10:45 at LPTMC, Jussieu, tower 13-12, 5th floor, room 5-23 SEM-LPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée) cond-mat.mes-hall
Tin Sulejmanpasic ( LPT-ENS ) Fractionalization between the vacua: from QCD to quantum magnetism
Abstract: Quantum Chromodynamics (QCD) -- the theory of strong nuclear forces -- has baffled the physics community and remains one of the poorly understood parts of the standard model. Its quintessential property: the confinement of quarks into protons, neutrons and mesons, while verified both experimentally and numerically, remains an elusive theoretical problem. The various cousins of QCD are however possible to understand to varying degrees and precision. In some of these theories the vacuum state is degenerate, and hence allows for domain walls -- a surface excitation which interpolates between two vacua of the theory. These domain walls have a remarkable property that quarks become liberated on them, and the domain wall excitation spectrum is very different from that of the bulk. Such QCD cousins are, unfortunately, not the physical theory, and they do not occur in nature. QCD however has another unlikely cousin: the Valence Bond Solid (VBS) state of the quantum anti-ferromagnet, where spin 1/2 excitations (or spinons) are bound into spin 1 excitations by a mechanism very similar to confinement of quarks. Perhaps surprisingly the low energy theory describing the behavior of the VBS phase is virtually identical to its QCD cousins under certain conditions. Further the VBS phase may have multiple vacua, and thus support domain walls, which in turn support liberated spinon excitations absent in the bulk. This has been verified numerically in the so-called J-Q model. These domain wall modes can in fact be seen as edge modes akin to those of the symmetry protected topological state. A multidisciplinary effort is slowly emerging to understand such phenomena, from the theoretical aspects of fundamental and condensed matter physics, to the numerical efforts in trying to understand QCD and quantum magnets.

Monday 19 March 2018, 11:00 at IPHT, Salle Claude Itzykson, Bât. 774 IPHT-PHM (Séminaire de physique mathématique) math-ph
Federico Zerbini ( IPhT ) String amplitudes in genus one: from open to closed strings.
Abstract: The Feynman diagram expansion of scattering amplitudes in perturbative superstring theory can be written as a series of integrals over compactified moduli spaces of Riemann surfaces with marked points, indexed by the genus. In genus zero one finds that open and closed string amplitudes can be described in terms of special values of multi-valued and single-valued polylogarithms, respectively, and are related by a map called single-valued projection. In this talk I want to report on recent evidence that an analogous statement can be made in genus one in terms of elliptic polylogarithms.

Monday 19 March 2018, 14:00 at IPHT, Salle Claude Itzykson, Bât. 774 IPHT-STA (Séminaire de Physique Statistique, CEA/Saclay) cond-mat
Martin Lenz ( LPTMS Orsay ) Slimming down through frustration
Abstract: Controlling the self-assembly of supramolecular structures is vital for living cells, and a central challenge for engineering at the nano- and microscales. Nevertheless, even particles without optimized shapes can robustly form well-defined morphologies. This is the case in numerous medical conditions where normally soluble proteins aggregate into fibers. Beyond the diversity of molecular mechanisms involved, we propose that fibers generically arise from the aggregation of irregular particles with short-range interactions. Using minimal models of frustrated aggregating particles, we demonstrate robust fiber formation for a variety of particle shapes and aggregation conditions. Geometrical frustration plays a crucial role in this process, and accounts for the range of parameters in which fibers form as well as for their metastable, yet long-lived character.

Monday 19 March 2018, 14:30 at IHES, Amphithéâtre Léon Motchane
( Séminaire Géométrie et groupes discrets )
MATH-IHES (TBA) hep-th
Anne Parreau ( Université Grenoble Alpes ) Geodesic currents, positive cross-ratios and degenerations of maximal representations
Abstract: Degenerations of maximal representations of a surface group may be seen as maximal representations in Sp(2n,F) for some non-Archimedean real closed field F. We associate to every such maximal representation a geodesic current whose intersection number is the length function of the representation for the L^1 norm. When the current is a measured lamination, we reconstruct an equivariant isometric embedding of the dual real tree in the Bruhat-Tits building of Sp(2n,F). This involves a general construction of an intersection current associated to a non necessarily continuous positive cross-ratio. This is joint work with Marc Burger, Alessandra Iozzi, and Beatrice Pozzetti.

Monday 19 March 2018, 16:00 at IPN, Salle A201 IPN-X (Séminaire commun de physique théorique des particules IPN-CPHT-X) hep-ph
Miguel Garcia Echevarria ( INFN Pavia ) Unraveling the 3D structure of the proton
Abstract: The quark/gluon 3-dimensional (3D) content of the proton in momentum space is encoded in the so-called Transverse Momentum Dependent functions (TMDs). In this talk I will give an overview of the TMD factorization and resummation formalism, paying special attention to gluon TMDs.

Monday 19 March 2018, 16:30 at IHES, Amphithéâtre Léon Motchane
( Séminaire Géométrie et groupes discrets )
MATH-IHES (TBA) hep-th
Charles Frances ( Université de Strasbourg ) Dynamics and topology on 3-dimensional Lorentz manifolds
Abstract: A classical result of Myers and Steenrod states that the isometry group of a compact Riemannian manifold is a compact Lie transformation group. Also classical is the fact that this compactness property fails for general pseudo-Riemannian manifolds, allowing interesting dynamics for the group of isometries. In this talk, we will be interested by the topological, and dynamical consequences of the noncompactness of the isometry group. We will especially focus on the case of Lorentz manifolds, and we will present a complete topological classification of 3-dimensional closed Lorentz manifolds having a noncompact isometry group.

Tuesday 20 March 2018, 14:00 at APC, 483A - Malevitch APC-TH (Seminar of the theory group of APC) hep-th
Nelson Merino ( APC, Université Paris Diderot ) Chern-Weil theorem, Lovelock Lagrangians in critical dimensions and boundary terms in gravity actions
Abstract: We show how to translate into tensorial language the Chern-Weil theorem for the Lorentz symmetry, which equates the difference of the Euler densities of two manifolds to the exterior derivative of a transgression form. For doing so we need to introduce an auxiliary, hybrid, manifold whose geometry we construct explicitely. This allows us to find the vector density, constructed out of spacetime quantities only, whose divergence is the exterior derivative of the transgression form. As a consequence we can show how the Einstein-Hilbert, Gauss-Bonnet and, in general, the Euler scalar densities can be written as the divergences of genuine vector densities in the critical dimensions D=2,4, etc. As Lovelock gravity is a dimensional continuation of Euler densities, these results are of relevance for Gauss-Bonnet and, in general, Lovelock gravity. Indeed, these vectors which can be called generalized Katz vectors ensure, in particular, a well-posed Dirichlet variational principle.

Tuesday 20 March 2018, 17:15 at DPT-PHYS-ENS, room Jean Jaurès (29 rue d'Ulm) SEM-PHYS-ENS (Colloquium du Département de Physique de l'ENS) cond-mat.str-el
Gabriel Kotliar ( Rutgers University ) Towards a Predictive Theory of Strongly-Correlated Electron Materials
Abstract: The standard model of solids, grounded on Fermi-Liquid theory and powerful computational techniques, provides an accurate description of many materials of great technological significance. Correlated electron systems are materials which fall outside the standard model of solid-state physics. They display remarkable emergent phenomena as for example metal to insulator transitions and unconventional high temperature superconductivity. The most recent example provided by the iron-based high-temperature superconductors. From a theoretical perspective correlated electrons pose a most challenging non-perturbative problem in physics. In this Colloquium, I will give an elementary introduction to the field of strongly correlated electron systems and Dynamical Mean Field Theory (DMFT) a non-perturbative method which provided a zeroth order picture of the strong correlation phenomena in close analogy with the Weiss mean-field theory in statistical mechanics. Applications to materials containing f and d electrons will be presented to show how the anomalous properties of correlated materials emerge from their atomic constituents. Different roads for the formation of strongly correlated states, will be traced to Mott Hubbard and Hunds physics. I will conclude with an outlook of the challenges ahead and the perspectives for rational material design using strongly-correlated materials.

Wednesday 21 March 2018, 13:45 at DPT-PHYS-ENS, ENS, salle tba SEM-PHYS-ENS (Colloquium du Département de Physique de l'ENS) quant-ph
Denis Vasilyev ( IQOQI Innsbruck ) A Quantum Scanning Microscope for Cold Atoms and an overview of a 'Few-Atom' Quantum Optical Antenna
Abstract: I will present my recent work made in IQOQI. The main part of the talk is devoted to the quantum scanning microscope arXiv:1709.01530 (to be published in PRL) We propose and analyze a scanning microscope to monitor `live' the quantum dynamics of cold atoms in a Cavity QED setup. The microscope measures the atomic density with subwavelength resolution via dispersive couplings to a cavity and homodyne detection within the framework of continuous measurement theory. We analyze two modes of operation. First, for a fixed focal point the microscope records the wave packet dynamics of atoms with time resolution set by the cavity lifetime. Second, a spatial scan of the microscope acts to map out the spatial density of stationary quantum states. Remarkably, in the latter case, for a good cavity limit, the microscope becomes an effective quantum non-demolition (QND) device, such that the spatial distribution of motional eigenstates can be measured back-action free in single scans, as an emergent QND measurement. In the final part of the talk I will present an overview of our ongoing work involving cold Rydberg atoms in regular arrays forming an optical antenna arXiv:1802.05592 We describe the design of an artificial `free space' 1D-atom for quantum optics, where we implement an effective two-level atom in a 3D optical environment with a chiral light-atom interface, i.e. absorption and spontaneous emission of light is essentially unidirectional. This is achieved by coupling the atom of interest in a laser-assisted process to a `few-atom' array of emitters with subwavelength spacing, which acts as a phased-array optical antenna. We develop a general quantum optical model based on Wigner-Weisskopf theory, and quantify the directionality of spontaneous emission in terms of a Purcell $\beta$-factor for a given Gaussian (paraxial) mode of the radiation field, predicting values rapidly approaching unity for `few-atom' antennas in bi- and multilayer configurations. Our setup has for neutral atoms a natural implementation with laser-assisted Rydberg interactions, and we present a study of directionality of emission from a string of trapped ions with superwavelength spacing.

Wednesday 21 March 2018, 14:00 at LPTENS, LPTENS library JOUR-CLUB (Journal Club) hep-th
Fedor Smirnov ( UPMC ) ``On space of integrable quantum field theories''
Abstract: (based on 1608.05499 )

Thursday 22 March 2018, 10:00 at IHP, 314 RENC-THEO (Rencontres Théoriciennes) hep-th
Nikolay Bobev ( KU Leuven ) An Étude on 3d N=2 Conformal Manifolds
Abstract: I will discuss the one-dimensional complex conformal manifold that controls the infrared dynamics of a three-dimensional N=2 supersymmetric theory of three chiral superfields with a cubic superpotential. Two special points on this conformal manifold are the XYZ model and three decoupled copies of the critical Wess-Zumino model. The conformal manifold enjoys a discrete duality group and can be thought of as an orbifold of CP1. I will describe how to compute the spectrum of low lying operators and their OPE coefficients as a function of the coordinates on the conformal manifold using the epsilon-expansion and the numerical conformal bootstrap.

Thursday 22 March 2018, 10:00 at IHES, Amphi. Léon Motchane
( Cours de l'IHES )
MATH-IHES (TBA) hep-th
Bertrand Eynard ( IPht, CEA Saclay ) Topological recursion, from enumerative geometry to integrability (2/4)

Thursday 22 March 2018, 11:00 at IPN, Salle des Conseils IPN-X (Séminaire commun de physique théorique des particules IPN-CPHT-X) hep-ph
Cristian Pisano ( Cagliari U. ) A first extraction of quark TMDs from a global analysis of ep and pp data
Abstract: Transverse momentum dependent parton distribution and fragmentation functions (TMDs) are fundamental objects that encode information on the intrinsic motion of quarks and gluons inside hadrons. As such, they provide a three-dimensional picture of hadrons in momentum space. Here we present the first extraction of unpolarized quark TMDs, inside unpolarized protons, through a simultaneous analysis of semi-inclusive deep-inelastic scattering, Drell-Yan and Z boson hadroproduction processes.

Thursday 22 March 2018, 11:45 at IHP, 314 RENC-THEO (Rencontres Théoriciennes) hep-th
Stefano Massai ( University of Chicago ) String theory of supertubes
Abstract: In string theory, black hole microstates at finite coupling give rise to horizon-scale structures that play an important role in addressing the information paradox. These are based on configurations of branes puffed up by the supertube effect. I will show that such supertubes admit an exact worldsheet treatment as gauged Wess-Zumino-Witten models. This description includes both BPS and non-BPS three-charge microstates. These constructions reveal stringy structures that support precursors of the long strings which hold most of the entropy in the dual CFT.

Thursday 22 March 2018, 14:00 at LPT, 110 LPT-COSM (Seminar of the Gravity and cosmology group of LPT) gr-qc
Sebastian Garcia-Saenz ( IAP ) Vortex lines in fluids - from string theory
Abstract: Thin vortices in fluids and superfluids admit an effective field theory (EFT) description in which they can be treated as one-dimensional extended objects, or strings. In this theory, vortex lines can interact among each other as well as with the “bulk” fluid by the exchange of phonons, whose dynamics can be described by a simple scalar effective theory. The coupling between vortices and sound is however more complicated, as it requires switching to a magnetic-type dual formulation in which the phonon field is encoded by a gauge two-form. After a review of the theory and its applications, I will discuss recent work where we show that the EFT can be recast into the simpler scalar field language, in a description that is valid for closed string configurations and for bulk modes of wavelength much longer than the typical string size. This is essentially a systematic expansion of the original EFT in which the string is regarded as a point-like source with degrees of freedom given by the string’s multipole moments. As an illustration we compute the sound emitted by an oscillating vortex ring, a calculation that in our field theory language reduces to a simple Feynman diagram to leading order.

Thursday 22 March 2018, 16:00 at LPT, 114 LPT-PTH (Particle Theory Seminar of LPT Orsay) hep-ph
Pawel Kozów ( Warsaw University ) Same-sign WW scattering at the LHC: can we discover BSM effects before discovering new states?
Abstract: It is possible that measurements of vector boson scattering (VBS) processes at the LHC will reveal disagreement with Standard Model predictions, but no new particles will be observed directly. The task is then to learn as much as possible about the new physics from a VBS analysis carried within the framework of the Effective Field Theory (EFT). I will discuss issues related to the correct usage of the EFT when the WW invariant mass is not directly accessible experimentally, as in purely leptonic W decay channels. The strategies for future data analyses in case such scenario indeed occurs will also be proposed.

Friday 23 March 2018, 10:00 at IPHT, Salle Claude Itzykson, Bât. 774
( )
COURS (Cours) hep-th
Monica Guica ( IPhT ) Asymptotic symmetries, black holes, and holography (3/5)
Abstract: It is known since the work of Emmy Noether that continuous global symmetries lead to local conserved currents. In gauge theories such as electromagnetism or gravity, the currents associated to gauge transformations vanish because gauge symmetries are not physical symmetries, but rather redundancies of description. However, if the manifold on which the gauge theory is defined has a boundary and the gauge parameter does not vanish on it, then the associated conserved charge can be non-zero. Such gauge transformations that do not vanish at infinity are known as asymptotic symmetries and they act non-trivially on the space of states. \par Asymptotic symmetries make a natural appearance in holography, the proposed equivalence between a theory of quantum gravity on a given manifold and a field theory living on its boundary. More precisely, they should correspond to global symmetries of the dual field theory. Despite the huge success of the AdS/CFT holographic correspondence, holography for most spacetimes of interest remains very poorly understood. One may then hope that the study of asymptotic symmetries, especially when there is an infinite number of them, can shed light on the nature of the dual field theory. \par In this course, we will study several examples of gravitational backgrounds for which the group of asymptotic symmetries is infinite-dimensional, such as AdS$_3$, the near horizon of extreme black holes, and flat space. In the latter case, a parallel development relates asymptotic symmetries to the soft behaviour of scattering amplitudes, providing a new perspective on these well-known results. The black holes will always be lurking in the background. \\ \\ 1. Introduction to the covariant phase space formalism and construction of the conserved charges. \\ 2. Asymptotic symmetries of AdS$_3$ gravity and generalization to extreme Kerr black holes. \\ 3. Asymptotic symmetries of flat space: supertranslations, superrotations and the memory effect. \\ 4. Symmetries of scattering in flat space and relation to soft theorems.
  • 2017-2018.pdf (4503344 bytes) OPEN
  • 2018_Guica.pdf (4621649 bytes) OPEN

Friday 23 March 2018, 11:00 at IPN, Bâtiment 100, Salle A018 (Bibliothèque)
( $ $ )
IPN-THEO (Séminaire du groupe de physique théorique de l'IPN Orsay) nucl-ex|nucl-th
A. Fantina ( GANIL ) Nuclear physics inputs for core-collapse supernova and neutron-star physics
Abstract: Compact stars such as neutron stars and supernovae are unique laboratories to probe matter in extreme conditions. Nuclear physics experiments, in tandem with astrophysical observations, can give valuable insight in to the properties of dense matter encountered in these stellar objects. In this seminar, I will discuss the importance of some nuclear physics inputs in the description of these compact stars. In particular, the impact of nuclear masses of neutron-rich nuclei for the compact-star modelling will be discussed. Moreover the dense matter found in neutron stars and supernovae being very neutron rich, a correct description of the symmetry-energy contribution to the nuclear energy is of great importance. The role of the symmetry energy on some properties of the neutron-star structure and composition will be addressed.
  • 2018_03_23_A_Fantina-commun.pdf (1180594 bytes) OPEN

Friday 23 March 2018, 14:00 at LPTENS, LPTENS library STR-LPT-ENS-HE (Séminaire commun LPTENS/LPTHE) hep-th
Michael Douglas ( Stony Brook ) Computational complexity of cosmology in string theory
Abstract: Title: Computational complexity of cosmology in string theory Abstract: We describe a new approach for quantum cosmology based on computational complexity. By defining a cosmology as a space-time containing a vacuum with specified properties (for example small cosmological constant) together with rules for how time evolution will produce the vacuum, we can associate global time in a multiverse with clock time on a supercomputer which simulates it. We argue for a principle of ``limited computational complexity" governing early universe dynamics as simulated by this supercomputer, which translates to a global measure for regulating the infinities of eternal inflation. We also give various definitions of the computational complexity of a cosmology, and argue that there are only a few natural complexity classes. (based on 1706.06430 )

Monday 26 March 2018, 09:45 at LPTM, Maison internationale de la recherche, Neuville-sur-Oise.
( See: )
WORK-CONF (Workshop or Conference) nlin
V. Hakim, G. Giacomin, S. Lepri, S. Olmi, M Baer, H. Chate, B. Fernandez Synchronization and Transport in Complex Systems
Abstract: The meeting will address subjects in areas ranging from statistical physics to biology, from applied mathematics to computational neuroscience. In particular, the speakers will present specific talks on active matter (e.g. on cell migration and on dynamics of bacterial suspensions), as well as on neural systems (on seizure propagation in the brain and on synchronization of neural networks) and on transport in oscillator chains and in random graphs. The presentation of the subjects will allow participants from different disciplines to profit of the proposed talks.

Monday 26 March 2018, 10:45 at LPTMC, tower 13-12 room 5-23 SEM-LPTMC (Séminaire du Laboratoire de Physique Théorique de la Matière Condensée) cond-mat.mes-hall
Giulio Biroli ( IPhT Saclay and LPS ENS ) Emergent phenomena in large interacting ecosystems
Abstract: I will first start with a general introduction on theoretical ecology, stressing the reasons that make connections with statistical physics interesting and timely. I will then focus on Lotka-Volterra equations, which provide a general model to study large assemblies of strongly interacting degrees of freedom in many different fields: biology, economy and in particular ecology. I will present our analysis of Lotka-Volterra equations as model of ecosystems formed by a large number of species and show the different phases that emerge. Two of them are particularly interesting: when interactions are symmetric we find a regime characterised by an exponential number of multiple equilibria, all poised at the edge of stability for a large number of species. For non symmetric interactions, this phase is replaced by a chaotic one. I will then conclude discussing relationships with experiments and general consequences of our works.

Tuesday 27 March 2018, 10:30 at IHES, Amphi. Léon Motchane
( Cours des Professeurs Permanents de l'IHES )
MATH-IHES (TBA) hep-th
Hugo Duminil-Copin ( IHES ) The Self-Avoiding Walk Model (4/4)
Abstract: The course will focus on rigorous results for the self-avoiding walk model on lattices, with a special emphasis on low-dimensional ones. The model is defined by choosing uniformly at random among random walk paths starting from the origin and without self-intersections. Despite its simple definition, the self-avoiding walk is difficult to comprehend in a mathematically rigorous fashion, and many of the most important problems illustrating standard challenges of critical phenomena remain unsolved. The model is combinatorial in nature but many questions about the stochastic properties of these random paths can be solved by combining nice combinatorial features with probabilistic techniques. In the course, we will describe some of the recent techniques developed in the area, including the use of discrete holomorphicity to understand the model on the hexagonal lattice.

Tuesday 27 March 2018, 11:00 at LPTHE, Library LPTHE-PPH (Particle Physics at LPTHE) hep-ph
Alon Faraggi ( Liverpool U. ) Wilsonian dark matter candidates in heterotic-string vacua
Abstract: Stable string states arise in string models due to Wilson line breaking of GUT symmetries. I will describe a new class of such Wilsonian dark matter states that emerge in string derived Z' model. The string construction utilises the spinor-vector duality symmetry to obtain a viable low scale Z' model. I will describe the nature of this duality and its role in the construction of the string model. I will describe the systematic classification tools, developed with Kounnas and Rizos, to analyse large classes of free fermionic string vacua. These methods were instrumental in the discovery of the spinor-vector duality, as well as in the trawling of the string Z' model. Other dark matter candidates that arise in string model will be briefly discussed.

Tuesday 27 March 2018, 11:30 at LPTENS, LPTENS library STR-LPT-ENS-HE (Séminaire commun LPTENS/LPTHE) hep-th
Apratim Kaviraj ( LPTENS ) TBA
Abstract: TBA

Tuesday 27 March 2018, 14:00 at APC, 483 A - Malevitch APC-TH (Seminar of the theory group of APC) hep-th
Jean-Paul Blaizot ( IPhT ) TBA

Thursday 29 March 2018, 10:00 at IHES, Amphi. Léon Motchane
( Cours de l'IHES )
MATH-IHES (TBA) hep-th
Bertrand Eynard ( IPht, CEA Saclay ) Topological recursion, from enumerative geometry to integrability (3/4)

Thursday 29 March 2018, 11:00 at LPTM, 4.13 St Martin II SEM-LPTM-UCP (Seminaires du LPTM , Universite de Cergy Pontoise) math-ph
Grégoire Misguich ( IPhT DRF Saclay/LPTM Cergy ) Out-of-equilibrium dynamics of quantum spin chain
Abstract: We study the dynamics of a quantum spin chain (S=1/2 XXZ model), which is prepared at t=0 in a domain-wall initial sate, where the spins are initially pointing up on the left half-line and down on the right half-line. Using extensive time-dependent DMRG simulations we analyze the evolution of the magnetization profile, as a function of the anisotropy parameter (Delta) the Hamiltonian. These numerical results are compared with the predictions of a recently developed hydrodynamics approach [Castro-Alvaredo et al., PRX 2016 and Bertini et al. PRL 2016], which generalizes the conventional hydrodynamics to integrable one-dimensional quantum systems. For this domain wall problem the situation of the isotropic Heisenberg model (Delta=1) is particularly interesting and not yet fully understood, and at this point our data suggest a diffusive behavior [Misguich, Mallick & Krapivksy, PRB 2017].

Thursday 29 March 2018, 11:00 at LPTHE, bibliothèque SEM-DARBOUX (Séminaire Darboux - physique théorique et mathématiques) math|math.MP
Nicolas Bergeron ( IMG-PRG ) TBA

Thursday 29 March 2018, 15:00 at IPHT, Amphi Claude Bloch, Bât. 774 SCOPI (Séminaire SCOPI Paris-Saclay) physics
Joël Bergé ( ONERA ) MICROSCOPE : the first results
Abstract: MICROSCOPE is a CNES/ONERA space mission that aims to test the Weak Equivalence Principle (WEP) at the $10^-15$ level, i.e. two orders of magnitude better than the best on-ground tests to date. The WEP is the cornerstone of General Relativity, the postulate that led Einstein to establish his theory: it states that all bodies fall at the same rate, independently of their mass and composition. \par Alternative theories of gravity, like those developed to overcome such conundrums as dark energy or the unification of gravity with the forces of the standard model of particle physics, generically predict a small violation of the WEP. \par As a consequence, not only does MICROSCOPE test the very foundation of General Relativity, but it also provides new constraints on theories beyond Einstein's. \par The MICROSCOPE satellite was launched on April 25, 2016. It has since then provided high-quality data. The first results (using only a small part of the total data) were announced last December, together with updated constraints on new long-range forces and on the characteristics of string theory's dilaton. In this talk, I will first introduce the MICROSCOPE mission, in particular its scientific goals and measurement principles. I will then present the exploitation phase up to now. Finally, I will discuss its first results.

seminars from series at institute
in subject with field matching

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