Seminar project proposal #01 - Aix-Marseille University...Supervisor: Alain Barrat Tel: e-mail: [email protected] Project title: From Static to Temporal Networks Abstract:

Master de Physique 2016-2017

spécialit é M2 : Physique Th éorique et Math ématique, Physique des Particules et Astroparticules

Seminar project proposal #01

Lab: Centre de Physique Théorique Research team: Dynamical Systems

Supervisor: Xavier Leoncini Tel: 04 91 26 95 38

e-mail: [email protected]

Project title: Self-organization in long range interacting systems

Abstract: Dynamics of many-body long-range interacting systems will be investigated.

Long range interacting systems are everywhere in physics, most notably due to gravitation or electromagnetic interactions, but these occur as well in gophysical flows or plasma physics. In this seminar, different aspects related to the dynamics and self-organization observed in toy-models will be discussed.

References: A. Campa, T. Dauxois and S. Ruffo, Statistical mechanics and dynamics of solvable models with long-range interactions, Phys. Rep., 480, 57-159 (2009)

R. Bachelard and C. Chandre and D. Fanelli and X. Leoncini and S. Ruffo, Abundance of regular orbits and out-of-equilibrium phase transitions in the thermodynamic limit for long-range systems, Phys. Rev. Lett., 2008

X. Leoncini and T. L. Van den Berg and D. Fanelli, Out of equilibrium solutions in the XY-Hamiltonian mean field model, EPL, 2009

Alessio Turchi, Duccio Fanelli and Xavier Leoncini, Emergence of a collective crystal in a classical system with long-range interactions EPL, 111 (2015) 30011




Lab: Centre de Physique Théorique Research team: Statistical Physics and Complex systems



Project title: Influence of network topology on the macroscopic evolution of interacting agents

Abstract: In this seminar, one will disscuss how the topology of a particular network model influences the thermodynamic behavior of a dynamical system defined on it. The notion of effective (fractal-like) network dimension will be introduced and the macroscopic chaotic behaviour discussed.

References: Sarah de Nigris and Xavier Leoncini, Hidden Dimensions in an Hamiltonian System on Networks, in Complex Motions and Chaosin Nonlinear Systems, Valentin Afraimovich, José António Tenreiro Machado, Jiazhong Zhang, Editors, Springer 2016




Lab: Centre de Physique Théorique Research team: Dynamical Systems



Project title: Hamiltonian Chaos, Fractional Derivatives and anomalous transport Abstract: Some consequences of typical chaotic behavior on transport properties will be discussed, notably the emergence of so called anomalous transport (in the sense of non-Gaussian) and how we could try to model this phenomenon by modifying the classical diffusion equation using fractional derivatives.

References: G. M. Zaslavsky, chaos, fractional kinetics, and anomalous transport, Phys. Rep., 371, 461-580 (2002)




Lab: CPPM Research team: HESS/CTA

Supervisor: Jean-Pierre Ernenwein Office: 334

e-mail: [email protected] Project title: Bibliographic study of Microquasars

Abstract: The purpose of this work is to study the known microquasars in our galaxy (X-ray binaries made of a donor star, a compact object accreting material from the donor star, and jets). First, a general study of the properties of these objects has to be done: typical parameters of the objects in play (mass, size, luminosity, orbital parameters), mechanisms (accretion, ejection, particles and fields involved, type and origin of radiation emitted and the location of its emission in the microquasar system -disk, corona/jets-), X-ray behavior (luminosity, hardness, quasi-periodic oscillations, and associated observational diagrams) and its link with the physics in the microquasar system, radio behavior (correlation with X-rays). Also the models predicting the production of high energy gamma-rays will have to be investigated (leptonic, hadronic). Then, after this first part dedicated to the global understanding of the objects, a study of the galactic microquasars which can be observed by the HESS experiment (in Namibia: Lat/Lon= -23.272, 16.5) will have to be done. Especially their characteristics and the flares undergone by these objects during the last decade will have to be described (from the papers published on the subject). You will finally attempt to conclude on which period would have been the most promising for a transient VHE gamma-ray emission.

References: https://arxiv.org/abs/1607.04613 (A search for very high-energy flares from the microquasars GRS 1915+105, Circinus X-1, and V4641 Sgr using contemporaneous H.E.S.S.

and RXTE observations)

https://arxiv.org/abs/1302.5485 (Black Hole Binaries and Microquasars)




Lab: CPPM Research team: SuperNemo Supervisor: Cassol Franca Tel: 0491827248 e-mail: [email protected] Project title: Phenomenology of Neutrinoless Double Beta Decay Abstract: The student will explore the current status of the neutrinoless double beta decay searches, which aim to answer the fundamental question of whether neutrinos are Dirac or Majorana particles. The study will span both theoretical and experimental expects and will take as reference the article of J.J. Gómez- Cadenas and Justo Martín-Albo http://arxiv.org/pdf/1502.00581v2.pdf References: http://arxiv.org/pdf/1502.00581v2.pdf




Lab: CPPM Research team: RENOIR Supervisor: GILLARD William Tel: e-mail: [email protected] Project title: The void in cosmology Abstract: In the cosmic web structure where large galaxy cluster are link together by filament of galaxy, cosmologic void, in between each filament, represent a large fraction of the cosmic web structure. Because of their weak matter density, the gravity field is negligible in cosmic void. Hence cosmic void are good candidate to study indirectly the effect of the dark energy. Indeed, cosmic void became recently new target of opportunity for cosmology physic and infer additional constraint on the dark energy component of our Univers. We propose the student to work on articles describing the usefulness of void in cosmology and to study which constraint void can put on the cosmological parameter and the accelerated expansion of the Univers, driven by the dark energy. References: Precision Cosmography with Stacked Voids [ArXiv:1110.0345] The Darkness that shaped the void : Dark Energy and Cosmic void [MNRAS-2012-440-61] Cosmic Void, Structure, Dynamic and Galaxie [CosPa 2011 41-66 ]


spécialité M2 : Physique Théorique et Mathématique, Physique des Particules et Astroparticules


Lab: Centre de Physique Théorique Research team: Statistical Physics and Complex Systems Supervisor: Alain Barrat Tel: e-mail: [email protected] Project title: From Static to Temporal Networks Abstract: The network paradigm (nodes joined by edges) is very useful to represent many systems of diverse origins, from the Internet or the WWW to social networks or biological networks. The increased availability of network datasets has allowed the field to make a lot of progresses in the last 15 years. Most of the corresponding studies in network science have until recently considered networks that do not evolve in time. However, the structure of many networks evolve over time. This is the case of for instance social networks, communication networks, transportation networks, etc. A recent development of the field concerns therefore the study of networks that evolve over time. The topic of the seminar consists in understanding some the fundamental differences between static and temporal networks, and the impact of these differences among various possible levels: how to represent these networks, how to characterise them, how to model them, and how to study processes on temporal networks. The references below are review articles that provide entry points into this field and give an overview of these differences.. References: http://arxiv.org/pdf/1508.01303.pdf http://arxiv.org/pdf/1108.1780.pdf




Lab: Centre de Physique Théorique Research team: Statistical Physics and Complex Systems Supervisor: Alain Barrat Tel: e-mail: [email protected] Project title: Impact of data incompleteness on simulations on epidemic processes, and how to estimate the epidemic risk from incomplete network data Abstract: The network paradigm (nodes joined by edges) is very useful to represent many systems of diverse origins, from the Internet or the WWW to social networks or biological networks. In particular, epidemic processes in a population can be understood as a diffusion process on the network of contacts between the individuals forming the population. The availability of data describing contacts between individuals allows therefore to devise better models of propagation. However, these data are sometimes incomplete. The goal of the seminar is first to understand and describe the impact that the incompleteness of data can have on the result of a diffusion process taking place on the network, using resampling techniques. Then, we will discuss how some representations of the data are left unchanged by the incompleteness of the data and how this property can be used to compensate for the biases obtained when incomplete data is used. References: http://www.nature.com/ncomms/2015/151113/ncomms9860/full/ncomms9860.html http://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1005002




Lab: CPPM Research team: Renoir

Supervisor: Dominique Fouchez

Tel: 04 91 82 76 49

e-mail: [email protected] Project title: Dark Energy

Abstract: The Candidate will expose the main lines about what is called "Dark Energy". Using both the theoritical point of view and the experimental/observational current measurements. The Candidate will find most relevant information in the Mortoson et al article

References: Mortoson et al (http://arxiv.org/abs/1401.0046)




Lab: cpt Research team: statistical physics Supervisor: Alberto Verga Tel: 0632078229 e-mail: [email protected] web: http://verga.cpt.univ-mrs.fr Project title: Chiral quantum walks Abstract: One interesting trend in physics is the interplay of quantum information and condensed matter. This seminar aims at introducing the basic concepts of quantum walks and networks, to uncover the relationships between symmetry and information transfer. In particular, it was recently experimentally demonstrated that breaking time-reversal symmetry, without affecting the unitarity of the dynamics, can enhance the transport of information in a quantum system evolving on a network [1]. References: [1] "Chiral quantum walks", Lu, D, Biamonte, J, Li, J, Li, H, Johnson, T, Bergholm, V, Faccin, M, Zimborás, Z, Laflamme, R, Baugh, J, and Lloyd, S, Phys. Rev. A 93, 042302 (2016) arXiv:1405.6209




Laboratory : Centre de Physique des Particules de Marseille (CPPM) Research team: ANTARES/KM3NeT Supervisor: Damien Dornic Tel : 00.33.4.91.82.76.82 E-mail : [email protected]

Project title : Multi-messenger analysis with KM3NeT Abstract:

Since few years, we assist to the birth of a new type of astronomy without light using others cosmic messengers like high-energy neutrinos, gravitational waves or ultra high-energy cosmic rays. In 2012, IceCube has detected the first astrophysical very high-energy neutrino signal detected in the South Pole. Up to now, few tens of events have been detected but their origins are still unkown. In 2015, LIGO has detected the first gravitational wave events from the merger of two black holes. In the next years, with the arrival of the new generation detectors (advanced LIGO/VIRGO, KM3NeT), more and more events will be detected. A huge effort to follow these events by more classical telescopes (optic, x-ray, radio, gamma-ray) is in place to help the identification of the sources. This combined effort is named multi-messenger analysis.

During this seminar, the student will study the possibility of mutli-messenger analysis in the context of sources like gamma-ray burst or intense blazars. In the Mediteranean sea, the neutrino telescope ANTARES has monitored the sky for about 10 years. Since 2015, we are building the second generation neutrino telescope, KM3NeT, with more or less a factor 20 better sensitivity compared to ANTARES.

Références : * High-energy Neutrino follow-up search of Gravitational Wave Candidate G184098 Adrián-Martínez et al., Phys. Rev. D 93, 122010

* Optical and X-ray early follow-up of ANTARES neutrino alerts Adrián-Martínez et al., JCAP02(2016)062 * Search for muon neutrino emission from GeV and TeV gamma-ray flaring blazars using 5 years of the ANTARES Telescope Adrián-Martínez et al., JCAP12(2015)014




Laboratory : Centre de Physique des Particules de Marseille (CPPM) UMR 6550 – CNRS/IN2P3 Université de la Méditerranée 163 avenue de Luminy – Case 902 13288 Marseille Cedex 09 FRANCE Research team: ANTARES/KM3NeT Supervisor: Vladimir Kulikovskiy Tel : 00.33.4.91.82.76.82 E-mail : [email protected] Project title : Detection of the MeV neutrino signal from supernova with KM3NeT Abstract: Nearly thirty years ago, 19 neutrino events with about 10 MeV energy coming from one supernova explosion (SN1987a) were observed by Kamiokande-II and IMB. Worldwide, several detectors currently running or nearing completion are much more sensitive compared to the ones which made this unique discovery. Since few years, newcomers have entered the game, IceCube & ANTARES, with a huge volume compared to the standard detectors built in caves. Since 2015, we are building the second generation neutrino telescope, KM3NeT, in the Mediteranean Sea, with more or less a factor 20 better sensitivity compared to ANTARES. The most innovative part of the KM3NeT detector is the segmented optical module. Its unique performance allows rejecting the optical background at the level of a single optical module and so provides a very high sensitivity SN search up to few tens of kpc.

During this seminar, the student will study the way to detect MeV neutrinos in neutrino telescopes and review in the case of a detection what can be determined in the general knowledge of the supernova explosion and on the intrinsic neutrino properties.

Références : * The IceCube Collaboration, A&A 535, A109 (2011); Böser S. et al, arXiv:1304.2553 * Scholberg K., Annual Review of Nuclear and Particle Science Vol. 62: 81-103 (2012) * Volpe C., J.Phys.Conf.Ser. 631 (2015) no.1, 012048




Lab: CPT Research team: Cosmology Supervisor: Tel: 04 91 26 95 05 e-mail: [email protected] Project title: How cosmology can bring information about the neutrino mass scale? Abstract: Since the discovery of flavour oscillations of neutrinos we know that they have a mass and

we know also the mass difference between each neutrinos. However, it is still a challenge to

estimate their absolute mass. That’s where particle physics can meet cosmology in order to

answer this question.

The cosmological implication of the presence of massive neutrinos in the universe can

provide some rough estimate of the maximum neutrino mass but the large scale structure of

the universe can help getting constraints on it.

Neutrinos behave in a different way depending on the temperature of the universe, when

their kinetic energy dominates they are relativistic and behaves as radiation (photons) while

when their potential energy dominates they behave as matter (non-relativist). This means

that it exists a transition between these two regimes which depends on their mass, thus if

this transition happened before the last scattering surface of the cosmological microwave

background then the Planck experiment would have constrained it very well but there is no

clue of this transition. Which means that it happened after the decoupling between photons

and atoms.

Since this transition happens when the universe is matter dominated, one can use the

large-scale structure of the universe in order to constrain the neutrino mass. In fact, when

neutrinos become non-relativist they start contributing to the gravitational evolution of

cosmic structures, their main impact is to slow down the growth on small scale. During this

seminar project, the student will read papers and reviews explaining how the neutrino mass

can be constrained by probing the large-scale distribution of matter in the universe.

References:

Julien Lesgourgues and Sergio Pastor, 2006, «Massive neutrinos and cosmology»

Castorina, Carbone, Bel, Sefusatti and Dolag, 2015, « DEMNUni: The clustering of

large-scale structures in the presence of massive neutrinos »


Spécialité M2 : Physique Théorique et Mathématique, Physique des Particules et Astroparticules


Lab: Centre de Physique Théorique 163, avenue de Luminy – case 907 13288 Marseille Cedex 9 Research team: Particle Physics Supervisor: Laurent Lellouch Tel: 04 91 26 95 17 e-mail: [email protected] Project title: Lattice Yang-Mills theories and Monte-Carlo simulations Abstract: This project is meant to be combined with the computing project on the same subject. Monte-Carlo methods are one of the only tools that we have to study gauge theories in their nonperturbative domaine where they confine « quarks » and « gluons » within « hadrons ». This requires regularizing these theories by placing them on a discrete spacetime. The goal of the combined seminar and computing project is to familiarize oneself with Yang-Mills theories and their most prominent properties; to understand how to discretize them; to learn the basics of Monte-Carlo methods; to write a C (or Fortran) code to simulate the SU(2) theory; to perform simulations to study some of this theory's key properties. Prerequisites for computing project: C or Fortran, fluently enough so that the coding (for the computing project) does not obscure the important physics References: Michael Creutz, ``Monte Carlo study of quantized SU(2) gauge theory,'' Physical Review D 21 (1980) 2308.




Lab: CPT Research team: Nanophysique Supervisor: Laurent RAYMOND Tel: 06 70 54 05 26 e-mail: [email protected] Project title: « Direct Measurement of the Density Matrix of a Quantum System » Abstract: It is well known that a quantum measurement perturbs the system on which it is performed. A way to avoid this fatality is to make use of the so-called weak-measurement method or to measure weak values[1]. Schematically, one can get a very partial information, but which has the advantage of perturbing the system in a very weak way, by repeating such experiments on several identical copies, a significant amount of information is recovered, without perturbation of the systems. Using this method, measurements of wave functions (or more recently of the density matrix) have been obtained experimentally. The goal of this work is to describe the different quantum measurement methods such as quantum state tomography[2], or this new Direct Measurement of the wave-function[3] or the density matrix[4]. References: [1] J. Dressel, M. Malik, F. M. Miatto, A. N. Jordan, and R. W. Boyd Rev. Mod. Phys. 86, 307 (2014). [2] W. K. Wootters and B. D. Fields, Ann. Phys. (N.Y.) 191, 363 (1989). [3] J. S. Lundeen, B. Sutherland, A. Patel, C. Stewart, and C. Bamber, Nature 474, 188 (2011). [4] G. S. Thekkadath, L. Giner, Y. Chalich, M. J. Horton, J. Banker, and J. S. Lundeen, Phys. Rev. Lett. 117, 120401 (2016).




Lab: CPPM Research team: LHCb

Supervisor: Olivier Leroy Tel: 04 91 82 76 05

e-mail: [email protected] Project title: Lepton Flavour Non Universality in LHCb Abstract: During the past few years, several anomalies have shown up in the flavour sector. The largest one is observed by the BaBar, Belle and LHCb experiments and is 4.0 sigmas away from the Standard Model prediction. This is the 2-dimentional measurement of the RD* and RD quantities, where RD(*) is the ratio of branching fractions of B meson decaying to D(*) tau nu divided by the same branching fraction where the tau lepton is replaced by a muon or an electron. This is so far the strongest hint for Lepton Flavour Non Universality, which is not expected in the Standard Model. The student will present how this measurement has been performed by the LHCb experiment and why it is of crucial importance in the quest for Beyond the Standard Model physics. References: - ICHEP2016 talk, http://cds.cern.ch/record/2206866/files/LHCb-TALK-2016-231.pdf - LHCb paper, http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.115.111803




Lab:Centre de Physique Théorique Research team: Nanophysics team Supervisors:Thierry Martin, Thibaut Jonckheere, and Jérome Rech Tel: 0660321652 e-mail: [email protected], [email protected], [email protected] 4 seminar topics are proposed by this team (see proposals #17 to #20) ______________________________________________________________ Project title 1: Introduction to topological superconductors Abstract 1: Majorana fermions were initially found as the real-valued solution of the Dirac Equation. The search for Majorana fermions in particle physics has been ongoing since their proposal, with some serious candidates such as neutrinos. In second quantized formalism a Majorana fermion creation operator is related to its annihilation counterpart by a unitary transformation (sometimes a trivial one, the identity operator). At the beginning of the 20th century, Kitaev introduced a toy model of a one dimensional tight binding chain where p-wave pairing between neighboring fermions is present. Such topological superconductors have a gap of course, but their boundary states are described by Majorana operators. This opens up the possibility to search for the manifestation of Majorana fermions in a condensed matter setting. Unfortunately, p-wave pairing superconductors are difficult to find in nature, and theoreticians have examined ways to generate them in nanowires put in the proximity of a BCS superconductor, in the presence of both (Rashba) spin orbit coupling and Zeeman coupling. There are now some experimental claims that point out electronic transport signatures of Majorana Fermions. The purpose of the seminar is to perform a bibliographic search of the literature on this topic, with some guidance from the supervisors. The seminar is likely to also lead to a computer project and an internship project in the spring. References 1: A. Yu. Kitaev, Usp. Fiz. Nauk (Suppl.)171 (10), 131 (2001). M. Leijnse and K. Flensberg, Semicond. Sci. Technol. 27 (2012) 124003. J. Alicea Rep. Prog. Phys. 75, 076501 (2012). J. Alicea et al., Nature Phys. 7, 412 (2011). V. Mourik et al. Science, 336, Issue 6084, 1003 (2012)




Lab:Centre de Physique Théorique Research team: Nanophysics team Supervisors:Thierry Martin, Thibaut Jonckheere, and Jérome Rech Tel: 0660321652 e-mail: [email protected], [email protected], [email protected] Project title 2: Quasiclassical circuit theory of transport Abstract 2: Hybrid superconducting systems have constituted a field of intensive activity in nanophysics for the past 3 decades. They can be studied with different approaches, such as scattering theory generalized to superconductors, and more fundamentally from non-equilibrium statistical field theory called the Keldysh approach. At the heart of the matter are the transfer of Cooper pairs and Andreev reflection, when an electron impinging from a normal metal is reflected as a hole when it encounters a superconducting boundary. From the field theoretical point of view, the starting point is the Larkin-Ovchinikov set of equations for the 4x4 Nambu-Gorkov single particle Green’s function, whose solution often represents a daunting task. Circuit theory was invented by Y. Nazarov in order to generate results for quantum transport in a more accessible manner. The starting point is to describe diffusive metals and superconductors connected by links. We will introduce the Keldysh approach to non- equilibrium field theory for a system (normal metal or superconductor) which contains point like impurities. Upon averaging over impurity configurations, in the quasiclassical regime, this then leads to the Usadel equations, which are still difficult to solve in practice. These equations, as proposed by Nazarov, can be further simplified if one assumes that the nanocircuit considered consists of a finite number of homogeneous elements connected by nodes (large quantum dots with many electronic levels), which are each characterized by a 4x4 Green’s function. The solution for these Green’s function can be used to compute electronic current. In order to find the Green’s function of the nodes, one requires the conservation of a “matrix current” similar to the Kirchoff rules of electronics. Here the goal is not to understand the precise derivation of circuit theory, but rather to understand how it works, looking at the bibliography and illustrating it with a simple example studied recently by the nanophysics team of CPT (arXiv:1508.03289). This seminar can give rise to a computer project in the winter and maybe an internship in the spring. References 2: Yu; Nazarov, arXiv:cond-mat/9811155v1 Yu. Nazarov and Ya. Blanter, Quantum Transport, introduction to nanoscience, Cambridge University Press 2009 Rammer and Smith, Rev. Mod. Phys. 58, 323 (1986).




Lab:Centre de Physique Théorique Research team: Nanophysics team Supervisors:Thierry Martin, Thibaut Jonckheere, and Jérome Rech Tel: 0660321652 e-mail: [email protected], [email protected], [email protected] Project title 3: Levitons: noiseless Lorentzian wave packets in electron wave guides Abstract 3: Electronic quantum optics aims at reproducing quantum optics experimental scenarios with electrons injected one by one from a single electron source on an electronic quantum wave guide. These electrons can be partitioned at a quantum point contact, which is the electronic equivalent of a beam splitter in quantum optics, in order to achieve a Hanbury-Brown and Twiss partitioning experiment (intensity correlations between the transmitted and the backscattered output). In the integer quantum Hall effect, the wave guides are edge states which propagate in opposite directions along the boundary of a quantum Hall bar. One can thus also achieve the equivalent of a Hong Ou Mandel experiment, where two electrons collide at the location of a quantum point contact, with a tunable time delay between the two. Lorentzian wave packets, generated by a voltage pulse rather than a single electron source, were introduced over two decades ago by Levitov and coworkers. They bear the particularity that by carefully controlling their electronic content, they carry an integer number of electron charge just above the Fermi level, without spurious electron-hole pairs. The pure electronic nature of this Leviton (Lorentzian voltage pulse) can be probed by a Hanbury Brown and Twiss experiment. In this seminar, we aim at understanding the structure and properties of Levitons as they were initially proposed, to review recent work (Levitov PRL) and understand to what extent experiments on two dimensional electron gas have managed to uncover them in the real world. If some time remains, the bibliographical study will include the study of a recent paper by the nanophysics team where Levitons are explored in the strongly correlated state of the quantum Hall effect: there, it is found that unlike what is expected from recent papers, noiseless Lorenzian excitations must carry an integer electronic charge – rather than a fractional one. A numerical project is possible as a follow-up, and maybe an internship in the spring. References 3: J. Dubois, T. Jullien, F. Portier, P. Roche, A. Cavanna, Y. Jin, W. Wegscheider, P. Roulleau, and D. C. Glattli, Nature 502, 659 (2013). E. Bocquillon, V. Freulon, F. D. Parmentier, J.-M. Berroir, B. Pla_cais, C. Wahl, J. Rech, T. Jonckheere, T. Martin, C. Grenier, D. Ferraro, P. Degiovanni, and G. Feve, Ann. Phys. 526, 1 (2014). T. Jullien, P. Roulleau, P. Roche, A. Cavanna, Y. Jin, and D. C. Glattli, Nature 514, 603 (2014). L. S. Levitov, H. Lee, and G. B. Lesovik, J. Math. Phys. 37, 4845 (1996). D. A. Ivanov, H. W. Lee, and L. S. Levitov, Phys. Rev. B 56, 6839 (1997). J. Keeling, I. Klich, and L. S. Levitov, Phys. Rev. Lett. 97, 116403 (2006). J. Dubois, T. Jullien, C. Grenier, P. Degiovanni, P. Roulleau, and D. C. Glattli, Phys. Rev. B 88, 085301 (2013). J. Rech, D. Ferraro, T. Jonckheere, L. Vannucci, M. Sassetti, T. Martin , arXiv:1606.01122 Minimal excitations in the fractional quantum Hall regime




Project title 4: Introduction to Dynamical Coulomb Blocade in Electronic Quantum Transport Abstract 4: When an electron passes through an ideal tunnel junction, the current voltage characteristic is typically linear (Ohm’s law). In nanocircuits, the effect of Coulomb interactions manifests itself in several ways. The static Coulomb blockade, which operates for a quantum dot placed between two metallic leads, is an example: the presence of electron on the dot prohibits the tunneling of a second electron on this dot. Another manifestation of the Coulomb interaction occurs in ultra-small single tunnel junctions, provided that the junction is connected to an electromagnetic environment which is typically described by an impedance. This leads to a drastic modification of the current voltage characteristic: a zero bias anomaly. The purpose of this seminar is to study this phenomenon by reading the founding article on the topic, written in the book single charge tunneling (Devoret Grabert editors, 1992) by Ingold and Nazarov ("charge tunneling rates in ultra small tunnel junctions"). The article can be found in the following link: http://link.springer.com/chapter/10.1007/978-1-4757-2166-9_2#page-1 or arXiv:cond-mat/0508728 If interested, the student will derive the formula for the current, and if times allows, he/she will do a bit a bibliography in order to see what have been the recent developments in the field, experimentally and theoretically. Additional areas of interest include Coulomb Blockade for Shot Noise, for Josephson Junctions… References 4: F. Portier, “from electronic quantum optics to quantum microwaves”, Habilitation Thesis (2015). C. Altimiras et al. Phys Rev Lett 112, 236803 (2014). M. Hofheinz et al ; , Phys Rev Lett 106, 217005 (2011). P. Joyez, Phys Rev Lett 110, 217003 (2013).




Lab: UMR 7345 CNRS physique des interactions ioniques et moléculaires Research team: turbulence plasma

Supervisor: Y. Elskens

Tel: 0491 288 230

e-mail: [email protected] Project title: Integrating stochastic processes and rough paths : from mechanics to kinetic theory

Abstract: Trajectories of noisy processes are often modeled using functions which are not continuously differentiable. Typically, the velocity of a heavy particle in air is idealized as a continuous function $v$ whose increments only have finite quadratic variation ($\int_{t_0}^{t_1} | v(t + d t) - v(t) |^2 < \infty$), and integrating products like $\int_{t_0}^{t_1} f(v(t)) d v(t)$ calls for extensions of ordinary calculus. Two classical approaches, motivated by elementary properties of stochastic processes, were developed by Ito and Stratonovich ; the martingale property is central in these constructions. More recently, Lyons introduced rough paths, providing a general framework to deal with the non-differentiable limits of smooth processes. Applications to fluid dynamics, wave-particle interaction and condensed matter are numerous ; the aim is to characterize individual trajectories rather than just probability distributions obeying a diffusion equation. This seminar opens a way to research on the connection between microscopically reversible, hamiltonian dynamics, and macroscopically irreversible, diffusion-like dynamics. References: 1. Øksendal B: Stochastic differential equations -- An introduction with

applications. Sixth ed., Springer, Berlin (2010). 2. Ribeiro BV, Amato MA, and Elskens Y, Brownian regime of finite-N corrections to particle motion in the XY hamiltonian mean field model, Physica Scr. (at press), hal : 01316408 ; arXiv : 1605.05624.




Lab: Centre de Physique des Particules de Marseille Research team: ATLAS

Supervisor: Fabrice Hubaut / Kun Liu

Tel: 04 91 82 72 51 / 04 91 82 72 70

e-mail: [email protected] / [email protected] Project title: Study of the associated production of the Higgs boson with a pair of top quarks at LHC Abstract: The discovery of the Higgs boson at the Large Hadron Collider (LHC) by the ATLAS and CMS experiments has changed the perspective in particle physics and is generally seen as an opportunity to revise the Standard Model. One very promising way, taking advantage of the higher energy and luminosity during the Run 2 period, is to study the Higgs boson through its associated production with a pair of top quarks in multilepton final states. The observation of this process will allow a direct measurement of the top quark–Higgs boson Yukawa coupling in a process that is tree-level at the lowest order, which is otherwise accessible primarily through loop effects. This seminar will explore the latest measurement done by ATLAS. References: ATLAS-CONF-2016-058 https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/CONFNOTES/ATLAS-CONF-2016-058/


spécialité M2 : Physique Théorique et Mathématique, Physique des Particules et Astrophysiques


Lab: CPT Research team: Cosmology Supervisor: Federico Piazza Tel: 04 91 26 95 04 e-mail: [email protected] Project title: Faster than the speed of light. Is this a viable possibility? Abstract: It is not difficult to conceive a low-energy theory in which some degree of freedom propagates at a higher speed than the speed of light. Indeed, many models that explain the current acceleration of the Universe can present this feature, if some of their parameters are tuned accordingly. Whether or not this is a viable possibility is still a matter of debate in physics. Among many points of view, Arkani Hamed et al. (2006) argue against this possibility, giving classical and quantum arguments, based on causality and on the behaviour of the scattering amplitudes respectively. Others do not see any main contradiction in having superluminal speeds. For example, Babichev et al. (2008) revisit the classical causality arguments and find no pathologies. The goal of this seminar is for the student to understand the arguments presented in favour or against superluminality, possibly develop an opinion on the subject, and present and motivate such an opinion in a seminar. The argument based on the behaviour of the scattering amplitudes is a little technical for the M2 level, but it would be great if the student could at least have a taste of it. The causality arguments, on the other hand, should be well understood with the end of this work. Basic knowledge of the Lagrangian formalism in field theory, although not indispensable, is desirable.

References: Causality, analyticity and an IR obstruction to UV completion Allan Adams, Nima Arkani-Hamed (Harvard U., Phys. Dept.), Sergei Dubovsky (Harvard U., Phys. Dept. & CERN & Moscow, INR), Alberto Nicolis (Harvard U., Phys. Dept.), Riccardo Rattazzi (CERN). Feb 2006. 32 pp. Published in JHEP 0610 (2006) 014 CERN-PH-TH-2006-033, HUTP-06-A0005 DOI: 10.1088/1126-6708/2006/10/014 e-Print: hep-th/0602178 | PDF k-Essence, superluminal propagation, causality and emergent geometry Eugeny Babichev (Gran Sasso & Moscow, INR), Viatcheslav Mukhanov, Alexander Vikman (Munich U., ASC & Munich U.). Aug 2007. 34 pp. Published in JHEP 0802 (2008) 101 LMU-ASC-54-07 DOI: 10.1088/1126-6708/2008/02/101 e-Print: arXiv:0708.0561 [hep-th] | PDF




Lab: CPPM, Centre de Physique des Particules de Marseille. Research team: ATLAS

Supervisors: Georges Aad and Arnaud Duperrin

Tel: + 33 4 91 82 72 83

e-mails: [email protected] and [email protected] Project title: The Higgs boson interaction with other bosons and leptons, a gateway to discover New Physics. Abstract: After many decades of search, the ATLAS and CMS collaborations at the LHC discovered the Higgs boson in 2012. The Higgs boson interaction with other known elementary particles is special. The Higgs field does not represent a force nor a matter particle. It interacts with other particles in a particular way giving them a mass. Studying the Higgs interactions is a cornerstone in today's particle physics. Many theories predict new elementary particles that will interact with the newly discovered boson. With this work the student will learn how different measurements of the ATLAS experiment are combined to extract the best knowledge about the Higgs couplings to other particles and how to interpret these results in terms of possible scenarios including new undiscovered particles and forces.

References: [1] [ATLAS collaborations], Measurements of the Higgs boson production and decay rates and coupling strengths using pp collision data at √s =7 and 8 TeV in the ATLAS experiment, Eur. Phys. J. C76 (2016) 6 [2] http://atlas.web.cern.ch/Atlas/Collaboration/ and http://atlas.cppm.in2p3.fr/




Lab: CPT Research team: DQAS Supervisor: Annalisa Panati Tel: e-mail: [email protected] Project title: The vacuum in curved space-times Abstract: When introducing a curved background space-time, the notion of vacuum loose meaning. Several effect (Hawking, Unruh) suggest radiation effects or temperature changes can be obtained solely as effect of gravity or acceleration. Hadamard condition gives a criteria to identify states that can play the vacuum's role in a perturbative expansion. The student will be ask to give a short overview of the problem, and explain in more detail one aspect of his or her choosing. References: S.Fulling, Aspect of Quantum Field Theory on Curved Space-Time, Cambridge University Press, Cambridge, UK (1989) C.J. Fewster, Lectures on quantum field theory in curved spacetime, (2008) http://www.science.unitn.it/~moretti/Fewsternotes.pdf




Lab: Centre de Physique Théorique Research team: Particle physics

Supervisor: Jérôme Charles

Tel: 0491269502


Project title: The standard model of CP violation by Kobayashi and Maskawa

Abstract: The student will study the famous article by Kobayashi and Maskawa that implements CP violation in the weak interaction. In particular she/he will explain how the different options presented in the paper impact the particle content of the model.

References: M. Kobayashi and T. Maskawa; "CP-Violation in the Renormalizable Theory of Weak Interaction". Progress of Theoretical Physics, 49 (2): 652–657




Lab: CPPM, Centre de Physique des Particules de Marseille Research team: ATLAS

Supervisor: Marlon Barbero

Tel: 04 91 82 76 58


Project title: The upgraded ATLAS detector as a tool for Standard Model studies and New Physics discoveries Abstract: In 2012, the ATLAS and CMS collaborations have presented the first experimental discovery of a Brout-Englert-Higgs boson, until then the main missing piece to the Standard Model of particles. But there remain many hints that the Standard Model is substantially incomplete. To address fine studies of the new boson, as well as potential new physics searches, the Large Hadron Collider (LHC) will see in the coming years its performances increased. The LHC’s particle detectors also need to ensure equivalent if not better performances in the future, to address the new challenges brought by a more demanding LHC machine. In this seminar, the student will try to synthesize the link between the performance requirements of the ATLAS detector, the physics object to be studied, and how practically these detector upgrades are organized. References: - Selected pages from: ATLAS Phase-II Upgrade Scoping Document (CERN-LHCC-2015-020 LHCC-G-166 September, 2015) - The ATLAS upgrade program , arXiv:1409.5002v1 - …




Lab: CPT Research team: Geometry, Physics and Symmetries

Supervisor: Serge Lazzarini Tel: 04 91 26 97 94


Project title: On the energy-momentum tensor

Abstract: The concept of the energy-momentum tensor is central in field theory. However there are two main types: on the one hand, the canonical Noether energy-momentum tensor associated to translations, and, on the other hand, the

energy-momentum tensor obtained after funtional derivative with respect to the metric (gravitational field). The goal of the seminar project is to carry out a bibliographic study in the literature on the issue when these two concepts for the energy-momentum tensor coincide. References: The Energy-Momentum Tensor(s) in Classical Gauge Theories

http://arxiv.org/pdf/1605.01121

Canonical and gravitational stress-energy tensors

http://arxiv.org/pdf/gr-qc/0510044




Lab: CPPM Research team: ATLAS

Supervisor: Laurent Vacavant Tel: 04 91 82 76 24


Project title: The Higgs boson: the state of the art

Abstract:

The discovery in 2012 by the ATLAS and CMS Collaborations at the Large Hadron Collider of a new particle, compatible with the predicted Higgs boson of the Standard Model, is a major milestone for fundamental physics. Since then, one of the main priorities of the two experiments has been to study the exact nature of this new boson. Some of these studies have already been fruitful, while some other ones will still be pursued in the years to come as they require much more data.

In this seminar, the student will first review the measurements performed so far with ATLAS to characterize the Higgs boson, with a particular emphasis on the experimental challenges and techniques used. In a second part, the measurements yet to be done, notably the measurements of its couplings to heavy quarks and its self-coupling, will be discussed, again with a special attention to the implied experimental requirements on the detectors. References:

ATLAS Collaboration, « A Massive Particle Consistent with the Standard Model Higgs Boson observed with the ATLAS Detector at the Large Hadron Collider », Science vol.

338, no 6114, pages 1576-1582, http://science.sciencemag.org/content/338/6114/1524 further references to be discussed during the preparation of the seminar




Lab: CPT Research team: Statistical Physics & Complex Systems Supervisor: Michel Rouleux e-mail: [email protected]

Project title: Vorticity for quantum spin systems with continuous symmetry




Lab: CPT Research team: GPS Supervisor: Ogievetsky Tel: 04 91 26 95 33 e-mail: [email protected] Project title: Knots and braids Abstract: The aim is to to understand the construction of knot polynomials using the R-matrix technics (Yang—Baxter equation) arising in statistical mechanics. References (approximative list): Kassel, C., Rosso, M., & Turaev, V., "Quantum groups and knot invariants", Panoramas et Synthèses de la S.M.F., vol. 5, Société Mathématique de France, Paris, 1997 Prasolov, V. V., & Sossinsky, A. B. (1997). Knots, links, braids, and 3-manifolds: an introduction to the new invariants in low-dimensional topology (No. 154). American Mathematical Soc.. Witten E., "Quantum field theory and the Jones polynomial", Comm. Math. Phys., 121 (1989) Baxter, R. J. (2007). Exactly solved models in statistical mechanics. Courier Corporation.

Documents

Seminar project proposal #01 - Aix-Marseille University...Supervisor: Alain Barrat Tel: e-mail: [email protected] Project title: From Static to Temporal Networks Abstract: