Christophe Ringeval
Centre for Cosmology, Particle Physics and Phenomenology,
Institute of Mathematics and Physics,
Louvain University,
Chemin du Cyclotron 2,
1348 Louvain-la-Neuve, (Belgium)
E-Mail :
ringeval At fyma.ucl.ac.be
Office :
+32 (0)10 472 075
Fax : +32 (0)10 472 414
What am I doing?
Mainly early universe cosmology
which is concerned
by the universe viewed as a whole, but before the hundredth of a
billonth of a second after the Big Bang.
I have been interested in cosmic
strings, a kind of lineic vacuum topological defect,
both on the microscopic side with the study of fermionic currents
that can flow along these superconducting wires, and on the
cosmological side with the search of the signatures they may
imprint in the cosmic microwave
background radiation (CMB).
I am also working in
braneworld cosmology where
our spacetime has more than 4 dimensions. In such a framework,
modifications of the standard gravity law might be observable on small or very large
distances, while the mass quantization of the particles living in our
universe could find an explanation from the very existence of
the extra dimensions.
I am involved in the cosmological perturbation theory
which predicts the temperature fluctuations observed in
the CMB from initial
conditions set during the radiation era. The physical
processes involved in the early universe may let their imprints in
these initial conditions, thereby be detectable in the CMB
measurements. This may be the case for cosmic strings and extra
dimensions.
Inflation is a phase of quasi-exponentially
fast expansion of the early universe that seems to be required
by the current
CMB data. Indeed, besides solving the
homogeneity and flatness problem of the standard cosmological
scenario, inflation predicts the right initial conditions that
lead to the observed CMB temperature fluctuations.
In this framework, I am working on trans-Planckian
physics which is concerned by the study of new physics
phenomena that could show up around the Planck
length, i.e. at the earliest times in the universe
history. Inflation acts as a zoom on such tiny lengthes by streaching
them to cosmological distances today.
By means of the CMB mesurements, inflation is a powerful tool to probe the
particle physics theories in a extraordinary high energy regime, many orders
of magnitude greater than the particle physics experiments taking place in
accelerators. Hope is to change the status of the most speculative theories
as string,
M, or
quantum gravity theories, from protoscience to science.
My jobs :
- Post-doc (2002-2004) : University of Geneva (Ruth Durrer)
Cosmological perturbations theory, finite volume braneworlds (RS), CMB,
trans-Planckian physics...
Need details?
- PhD thesis :
Fermionic currents flowing along
extended objects (University of Paris 6)
Gzipped color postscript or djvu format.
- Curriculum vitae :
pdf or ps
Scientific tools :
- Useful libraries : Netlib repository. Fastest Fourier Transform of the West : FFTW
- Computers patch : Do you want your computer to
respect causality?
yes or
no
News :
- Bayesian model comparison for all the models of Encyclopaedia :
Bayes factors
- Aspic : checkout the new version of the aspic
library for computing slow-roll predictions
Hobbies :
Links :