相关论文: Nonlinear time-series analysis of Hyperion's light…

In this work we revisit the geometric approach to chaos in Hamiltonian dynamics, by means of the Jacobi-Levi-Civita equation (JLCE). We inspect numerically two low-dimensional dynamical systems; show that, along chaotic orbits, the…

[Abridged] Distant stars and planets will remain spatially unresolved for the foreseeable future. It is nonetheless possible to infer aspects of their brightness markings and viewing geometries by analyzing disk-integrated rotational and…

The bright ring-like structures observed in the images of M87* and SgrA* captured by the Event Horizon Telescope strongly support the validity of general relativity. Lensed images of the emission region, often referred to as photon rings in…

The Luminous Convolution Model (LCM) demonstrates that it is possible to predict the rotation curves of spiral galaxies directly from estimates of the luminous matter. We consider two frame-dependent effects on the light observed from other…

The "plane of satellites problem" describes the arrangement of the Milky Way's 11 brightest satellite galaxies in a remarkably thin plane, possibly supported by rotation. This is in apparent contradiction to the standard cosmological model,…

Young stellar objects in their pre-main sequence phase are characterized by irregular changes in brightness, generally attributed to an increase of the mass accretion rate due to various kind of instabilities occurring in the circumstellar…

Lyapunov exponents (LEs) are key indicators of chaos in dynamical systems. In general relativity the classical definition of LE meets difficulty because it is not coordinate invariant and spacetime coordinates lose their physical meaning as…

The High Energy Stereoscopic System (H.E.S.S.) is a southern hemisphere array of four Imaging Atmospheric Cherenkov Telescopes observing the sky in the very high energy gamma-ray range (E $>$ 100 GeV). VHE observations are an invaluable…

Hamiltonian trajectories are strictly time-reversible. Any time series of Hamiltonian coordinates {q} satisfying Hamilton's motion equations will likewise satisfy them when played "backwards", with the corresponding momenta changing signs :…

Research into light curves from stars (temporal variation of brightness) has completely changed how exoplanets are discovered or characterised. This study including star light curves from the Kepler dataset as a way to discover exoplanets…

We investigate the orbits of compact binary systems during the final inspiral period before coalescence by integrating numerically the second-order post-Newtonian equations of motion. We include spin-orbit and spin-spin coupling terms,…

The Kepler mission was launched in 2009 and has discovered thousands of planet candidates. In a recent paper, Esteves et al. (2013) found a periodic signal in the light curves of KOI-13 and HAT-P-7, with a frequency triple the orbital…

After the work of Gladman et al. (1998), it is now assessed that many irregular satellites are orbiting around Uranus. Despite many studies have been performed in past years, very few is know for the light-curves of these objects and…

The gravitational influence of a second satellite on the rotation of an oblate moon is numerically examined. A simplified model, assuming the axis of rotation perpendicular to the (Keplerian) orbit plane, is derived. The differences between…

It is first shown that the observational light curve data of R Scuti, a star of the RV Tau type, is not multi-periodic, and that it cannot have been generated by a linear stochastic (AR) process. By default, the signal must be a…

Recent studies have shown that there are discrepancies between observations and the theoretical predictions in some neutrino experiments at short distances. In the so-called "Reactor Antineutrino Anomaly" and in the "Gallium Anomaly", these…

The first objective of this thesis is to fill the lack in cosmology of a description on the past light cone: the null hypersurface on which observed signals propagate. Its second goal is to evaluate the importance of inhomogeneities in the…

Time-of-flight measurements of high-energy astrophysical neutrinos can be used to probe Lorentz invariance, a pillar of modern physics. If Lorentz-invariance violation (LIV) occurs, it could cause neutrinos to slow down, with the delay…

We present a synthetic galaxy lightcone specially designed for narrow-band optical photometric surveys. To reduce time-discreteness effects, unlike previous works, we directly include the lightcone construction in the \texttt{L-Galaxies}…

We present a systematic investigation of the rotational lightcurves of trans-Neptunian objects based on extensive optical data from Mauna Kea. Four of 13 objects (corresponding to 31%) in our sample ((33128) 1998 BU48, 2000 GN171, (20000)…