Universite Clermont Auvergne

Accueil du site > Pôles de Recherche > Théorie


A theoretical approach to particle physics, nuclear physics and cosmology cannot be separated from the corresponding experimental approach ; whilst in certain domains one may precede the other, a symbiosis between theory and experiment is crucial for the progress of both. While allowing for an active synergy with the experimental collaborations of the LPC, the research activities of the Theory Pole at the LPC encompass numerous topics of Particle Physics and Interdisciplinary Physics, within the framework of the IN2P3 research programme, being based in numerous national and international collaborations and networks.


Created in 1995, the Theory Pole is composed of four permanent members, both CNRS researchers, and professors at the UBP, and two postdoctoral researchers.

The scientific research topics of the team have evolved from hadronic physics (QCD and relativistic few body systems) and pluridisciplinary physics (percolation models applied to biomaterials), to being currently focused on particle physics : Field Theory, Standard Model and New Physics, as well as Astroparticle Physics. Our research aims at addressing several open questions

  • How are strongly interacting particles (quarks and gluons) confined in mesons and baryons ?
  • What is the origin of electroweak symmetry breaking ?
  • What is the nature of neutrinos ? Which is the mechanism responsible for their mass ?
  • Why is the Universe dominated by matter ? What was the mechanism responsible for baryogenesis ?
  • What is the nature of dark matter ?

Many of which are being (direct or indirectly) addressed by the "Particles, astroparticles and cosmologie" and "Hadronic matter" poles. The members of the group have important interactions with other LPC groups, especially ATLAS, LHCb and CKMFitter.

The Theory pole members contribute to the local scientific animation, and belong to the organising committees of a large number of national and international meetings (Schools, Workshops, Conferences), being also engaged in several Outreach activities ; they further hold numerous scientific and academic responsibilities (in national and international committees and boards).


The activities of the Theory Pole are currently focused on Particle Physics. The members pursue formal research in Field Theory, develop theoretical tools potentially applicable to particle physics, and carry extensive phenomenological studies in direct connection with experiment.
Our research revolves around the following axes :

  • Field Theory : field theory on the light front and finite field theories (based for instance on the Taylor-Lagrange renormalisation scheme). Application to physical observables in 3+1 dimensions and perturbative computation of radiative corrections to the Higgs boson mass.
  • Standard Model of Strong and Electroweak interactions : Lattice QCD
    • Semi-leptonic decays of B-mesons into the first orbital excitations of D-mesons
    • Computation of the renormalisation factor of local and non-local operators
    • Running of the strong coupling ; computation of Wilson coefficients on the lattice
  • Standard Model of Strong and Electroweak interactions : Precision tests (in the framework of the CKMFitter Collaboration)
  • Beyond the Standard Model : Searches for new physics
    • Direct searches of supersymmetric extensions of the SM (Next-to-Minimal Supersymmetric SM at the LHC - extended Higgs sector, difficult search scenarios)
    • Indirect searches - Heavy flavour physics (semi-leptonic B-decays, lepton universality tests,...) ; Impact of new states (SUSY) for Higgs properties ; Lepton flavour violation (low-energies and collider signatures)
  • Beyond the Standard Model : sterile fermions (neutrino mass generation, lepton properties, rare decays)
  • Dark Matter : New physics candidates, constraints on SUSY models (relic density, prospects for detection) ; Indirect dark matter detection (extragalactic gamma-ray background)
  • Furthermore, the Theory Pole has also contributed in the field of theoretical approaches to percolation, in close connection to biomaterial activities carried in the "Physics for health and environment" Pole.

For more details on the Theory Pole research activities, check the corresponding pages



  • Chandan Hati (CNRS postdoctoral fellow)
  • Jonathan Kriewald (UCA PhD student)
  • Jean-François Mathiot (CNRS research director)
  • Vincent Morénas (Professor, UCA)
  • Jean Orloff (Professor, UCA)
  • Ana M. Teixeira (CNRS researcher)


  • Vladimir Karmanov, Alexander Smirnov (Lebedev Institute, Moscow) : Field theory on the light front
  • Damir Becirevic, Benoit Blossier (LPT-Orsay) : Heavy flavours, Lattice QCD
  • Asmaa Abada (LPT-Orsay) : Lepton flavours, sterile neutrinos


  • Valentina De Romeri (Postdoctoral fellow, EU ITN "Invisibles" Network, 2013-2015)
  • Antoine Gérardin (Postdoctoral fellow, IN2P3, 2014-2015)
  • Gabriela Bailas (Ph.D. student, IN2P3, 2015-2018)
  • Mariam Atoui (Ph.D. student, 2010-2013)
  • Farvah Nazila Mahmoudi (MdC-UBP, 2008-2014)
  • Hubert Mély (Ph.D. student, 2008-2011)
  • Bruno Mutet (Postdoctoral fellow, 2010-2011)
  • Siavash Neshatpour (Ph.D. student, 2009-2013)
  • Natalia Tsirova (Postdoctoral fellow, 2008-2010)
  • Savvas Zafeiropoulos (Postdoctoral fellow, 2013-2014)


Jean-François Mathiot :
  • President of Committee for Scientific Prospectives of the LPC
Vincent Morénas :
  • Member of the 29th section of the CNU (Conseil National des Universités)
  • President of the local French Physical Society section (SFP-Auvergne)
  • PI of the "Lattice calculations in Hadronic Physics" IN2P3 project
Jean Orloff :
  • President of the UCA Physics Department
  • Member (elected) of Council of the UCA Physics and Engineering School
  • President of the Scientific Council of the LPC
  • President of the "Bureau des Théoriciens de Physique des Particules"
Ana Teixeira :
  • Vice-President and elected member of the LPC Council
  • Member of the COMET collaboration
  • PI of the "Lepton Flavours" IN2P3 project


The Theory Pole hosts, and/or is directly involved in the organisation of numerous national and international events : Workshops, Schools, Meetings...

European Union ITN ELUSIVES and RISE INVISIBLES PLUS : A. M. Teixeira, J. Orloff members
iTHEPHY Erasmus+ iTHEPHY Strategic Partnership for Innovating Team-Teaching for Physics
J. Orloff: french coordinator
"European Twisted Mass Collaboration":
V. Morénas: member of the collaboration
“CKMFitter” Project:
J. Orloff: member of the collaboration
"The International Light Cone Advisory Committee" - ILCAC:

J.-F. Mathiot: member of ILCAC
GdR “Terascale”:
J. Orloff: steering council of the GdR “Terascale”
A. M. Teixeira: coordinator of the “Beyond the SM” group
GdR “Neutrino”:
A. M. Teixeira: coordinator of the “Beyond the SM” group
GdR "Intensity Frontier":
A. M. Teixeira: coordinator of the "Interplay of Quark and Lepton Flavours" group


The Theory Pole hosts, and/or is directly involved in the organisation of numerous national and international events : Workshops, Schools, Meetings...

  • “Rencontres de Physique des Particules – RPP2019”, LPC, 23-25 January 2019 (J.-F. Mathiot, J. Orloff, V. Morénas, A. M. Teixeira, organising committee).
  • “Third International Conference on Charled Lepton Flavour Violation", Fukuoka, Japan 17-19 June 2019 ( A. M. Teixeira, IOC).
  • "Rencontres de Moriond - Electroweak session”, La Thuile, Italy (J. Orloff, organising committee).
  • “Cargèse International Summer Schools in High Energy Physics", Cargèse, France (J. Orloff, organising committee, 2007,2010,2012,2014,2018,2020).
  • “École d’été de physique e2ϕ”, Clermont-Ferrand, 25-28 August 2014 (Local organising committee : V. Morénas-president, J.-F. Mathiot).
  • “Invisibles Workshop 2014”, Institut des Cordeliers, Paris, 14-18 July 2014 (A. M. Teixeira, V. De Romeri, organising committee).
  • “Invisibles School 2014”, Château de Buton, Gif-sur-Yvette, 8-13 July 2014 (A. M. Teixeira, V. De Romeri, organising committee).
  • “GdR Neutrino" Plenary meeting at Clermont-Ferrand, LPC, 9-10 June 2015 (V. De Romeri, J. Orloff, A. M. Teixeira, organising committee).
  • “GdR Terascale" Plenary meeting at Clermont-Ferrand, LPC, 23-25 April 2012 (J. Orloff, A. M. Teixeira, organising committee).
  • “Rencontres de Physique des Particules – RPP2011”, LPC, 13-14 January 2011 (J.-F. Mathiot, J. Orloff, V. Morénas, A. M. Teixeira, organising committee).