Contact
Jean-Marc Gérard
Position
Professor
Address
Centre for Cosmology, Particle Physics and Phenomenology - CP3
Université catholique de Louvain
2, Chemin du Cyclotron - Box L7.01.05
B-1348 Louvain-la-Neuve
Belgium
Université catholique de Louvain
2, Chemin du Cyclotron - Box L7.01.05
B-1348 Louvain-la-Neuve
Belgium
Phone
+32 10 47 2712
Office
UCL member card
Teaching
Special Relativity
General Relativity
Quantum field theory 1
Fundamental interactions
Strong interactions and symmetries
Electroweak interactions
Introduction to kinematics and dynamics in Minkowski space-time.
PHY1223 (22.5h + 15h; shared with J.Govaerts)
PHY1223 (22.5h + 15h; shared with J.Govaerts)
General Relativity
Quantum field theory 1
Fundamental interactions
Strong interactions and symmetries
Introduction to perturbative QCD and to hadron physics.
PHY2223 (30h; shared with F.Maltoni)
PHY2223 (30h; shared with F.Maltoni)
Electroweak interactions
Introduction to the Standard Model.
PHY2224 (22.5h; shared with F.Maltoni)
PHY2224 (22.5h; shared with F.Maltoni)
People responsibilities
Postdocs
Former members
Jan Hajer
(member since October 2017)
BSM Phenomenology. Higgs physics, naturalness of the SM, SUSY. Hidden particles at NA62.
BSM Phenomenology. Higgs physics, naturalness of the SM, SUSY. Hidden particles at NA62.
Former members
Research statement
My interests cover the phenomenology of the four fundamental interactions.
Strong interactions
The use of an effective theory for Quantum Chromo Dynamics in the large-N limit to cast a new glance on:
-the U(1) problem and the resulting strong CP-violation;
-the non-perturbative effects on
and 
hadronic decays.
-the U(1) problem and the resulting strong CP-violation;
-the non-perturbative effects on
and hadronic decays.
Electroweak interactions
The use of Quantum Flavor Dynamics to get theoretical constraints on:
-the fermion mixings and the resulting weak CP-violation;
-the boson mass spectrum in multi-Higgs doublet models.
-the fermion mixings and the resulting weak CP-violation;
-the boson mass spectrum in multi-Higgs doublet models.
Gravitational interactions
The use of equivalence principles to test relativistic theories of gravity:
-around the Sun;
-in the early Universe.
-around the Sun;
-in the early Universe.
Projects
Research directions:
Experiments and collaborations:
Active projects
Non-active projects
Cosmology and General Relativity
Theories of the fundamental interactions
Phenomenology of elementary particles
Data analysis in HEP experiments
Theories of the fundamental interactions
Phenomenology of elementary particles
Data analysis in HEP experiments
Experiments and collaborations:
Active projects
CP and chiral symmetry in K physics.
Jean-Marc Gérard
Study anomalous effect on the
energy distribution and try to extract the 
parameter 
from experimental data.
Study anomalous effect on the
energy distribution and try to extract the parameter from experimental data.
Gravitational Wave Physics with Virgo
Diego Bardiaux, Giacomo Bruno, Federico De Lillo, Antoine Depasse, Jan Govaerts, Jean-Marc Gérard, Vincent Lemaitre, Andrew Miller, Krzysztof Piotrzkowski, Andres Tanasijczuk, Joris van Heijningen
In July 2018 CP3 members have joined the Virgo Collaboration at the European Gravitational Observatory (EGO) near Pisa in Italy. Virgo is the European laser interferometer for gravitational wave detection. After several years of instrument upgrades, Virgo went in observation mode in August 2017, about one year and half after the two LIGO interferometers in the US had detected for the first time gravitational waves. Virgo and LIGO work in close collaboration, sharing data, analysing data and publishing together. Fundamental research in gravitational wave experimental physics was funded for the first time in Belgium at the end of 2018 with a project led by UCLouvain and ULiege. On the data analysis side the plan is on one side to investigate the properties of binary black hole coalescence events, possibly relating them to theoretical models of dark matter and/or primordial black holes, and on the other to search for a stochastic gravitational wave background originating from the very early moments of the life of the Universe, a discovery that would be foundational for cosmology. On the instrumentation side, contributions to computing and the optical system of the Virgo interferometer are planned.
CP3 members are also actively supporting the Einstein Telescope project, a proposed underground laser interferometer project for gravitational wave detection that is expected to take over from LIGO and Virgo around 2030.
In July 2018 CP3 members have joined the Virgo Collaboration at the European Gravitational Observatory (EGO) near Pisa in Italy. Virgo is the European laser interferometer for gravitational wave detection. After several years of instrument upgrades, Virgo went in observation mode in August 2017, about one year and half after the two LIGO interferometers in the US had detected for the first time gravitational waves. Virgo and LIGO work in close collaboration, sharing data, analysing data and publishing together. Fundamental research in gravitational wave experimental physics was funded for the first time in Belgium at the end of 2018 with a project led by UCLouvain and ULiege. On the data analysis side the plan is on one side to investigate the properties of binary black hole coalescence events, possibly relating them to theoretical models of dark matter and/or primordial black holes, and on the other to search for a stochastic gravitational wave background originating from the very early moments of the life of the Universe, a discovery that would be foundational for cosmology. On the instrumentation side, contributions to computing and the optical system of the Virgo interferometer are planned.
CP3 members are also actively supporting the Einstein Telescope project, a proposed underground laser interferometer project for gravitational wave detection that is expected to take over from LIGO and Virgo around 2030.
On the unification of gauge coupling constants
Jean-Marc Gérard
In the standard model version of the grand unified theory different gauge couplings intend to, but do not, meet at some higher scale. Here we will look for some better ways for the unification of the gauge coupling constants.
In the standard model version of the grand unified theory different gauge couplings intend to, but do not, meet at some higher scale. Here we will look for some better ways for the unification of the gauge coupling constants.
Scalar-tensor theories of gravitation
Jean-Marc Gérard
The strong equivalence principle (SEP) does not hold anymore in various extensions of General Relativity. Its violations can be revealed by the non-universality of free-falling for compact objects and we have developed a generic and effective way to test the SEP in the Cosmic Microwave Background (CMB). A violation of the SEP indeed alters the amplitude of the acoustic oscillations in the primeval plasma. Using the WMAP data, we have contrained a possible SEP violation for the baryons.
Our interests are also focused on the scalar-tensor theories of gravitation and their cosmologies. In a more specific way, we are currently studying a model where the scalar sector is conformally invariant. The effective fluid related to the non-minimally coupled scalar field differs from the other cosmological fluids of radiation by its very particular anisotropic pressure and we are studying its impact on the CMB anisotropies by modifying the CAMB code.
The strong equivalence principle (SEP) does not hold anymore in various extensions of General Relativity. Its violations can be revealed by the non-universality of free-falling for compact objects and we have developed a generic and effective way to test the SEP in the Cosmic Microwave Background (CMB). A violation of the SEP indeed alters the amplitude of the acoustic oscillations in the primeval plasma. Using the WMAP data, we have contrained a possible SEP violation for the baryons.
Our interests are also focused on the scalar-tensor theories of gravitation and their cosmologies. In a more specific way, we are currently studying a model where the scalar sector is conformally invariant. The effective fluid related to the non-minimally coupled scalar field differs from the other cosmological fluids of radiation by its very particular anisotropic pressure and we are studying its impact on the CMB anisotropies by modifying the CAMB code.
Tensions in flavor physics and two Higgs doublet models
Jean-Marc Gérard
Study of the tensions observed between the K and the B meson systems and their implications for scalar-mediated flavor changing currents in the framework of two Higgs doublet models (2HDM).
Study of the tensions observed between the K and the B meson systems and their implications for scalar-mediated flavor changing currents in the framework of two Higgs doublet models (2HDM).
Non-active projects
in the SM and beyond.
and 
processes provide a powerfull tool to probe new physics (NP). Focusing on the 
mixing angle and to their masses and also to the vev of 
. The last quantity could contribute to the neutron EDM.
Publications in CP3
All my publications on Inspire
Number of publications as CP3 member: 35 Download BibTeX
Last 5 publications
More publications
Number of publications as CP3 member: 35 Download BibTeX
Last 5 publications
2020
CP3-20-08: Impact of eta0 on epsilon' / epsilon at the dawn of the 2020s
Andrzej J. Buras and Jean-Marc Gérard
February 3.
February 3.
2018
More publications