Related papers: Binary Pulsars as probes for Spin-2 Ultralight Dar…
We propose a possibility to improve the current precision measurements on compact binaries. When the orbital axis is almost perpendicular to our line of sight, a pulsar behind its companion can form two strong-lensing images. These images…
Particle dark matter could have a mass anywhere from that of ultralight candidates, $m_\chi\sim 10^{-21}\,$eV, to scales well above the GeV. Conventional laboratory searches are sensitive to a range of masses close to the weak scale, while…
Supermassive black hole binaries are the strongest gravitational wave sources in the universe. The systems most likely to be observed with pulsar timing arrays (PTAs) will have particularly high masses ($\gtrsim 10^9 M_\odot$), long periods…
Some of the theoretical challenges posed by the general relativistic description of binary systems of compact objects (neutron stars or black holes) are reviewed. We recall the various ways one can use the theory of the motion, and of the…
An ultralight scalar field is a candidate for the dark matter. The ultralight scalar dark matter with mass around $10^{-23}\,{\rm eV}$ induces oscillations of the pulse arrival time in the sensitive frequency range of the pulsar timing…
Unlike traditional electromagnetic measurements, gravitational-wave observations are not affected by crowding and extinction. For this reason, compact object binaries orbiting around a massive black hole can be used as probes of the inner…
Binary pulsars provide some of the tightest current constraints on modified theories of gravity and these constraints will only get tighter as radio astronomers continue timing these systems. These binary pulsars are particularly good at…
``Adding colour'' to the gravitational-wave sky by probing unexplored frequency bands has the potential to unveil new and unexpected phenomena in the Universe. In these proceedings, we summarise current efforts to probe gravitational waves…
Asteroseismology has become an indispensable method for measuring stellar ages and radii, while binary systems remain the most prevalent tool for determining stellar masses. The synergy of the two, namely pulsating stars in binary systems,…
Binary systems containing at least one radiopulsar are excellent laboratories to test several aspects of fundamental physics like matter properties in conditions of extreme density and theories of gravitation like the Einstein's General…
Scalar fields of masses between $10^{-21}\rm{eV}/c^2$ and $10^{-11} \rm{eV}/c^2$ can exhibit enhanced gravitational interactions with black holes, and form scalar clouds around them. Such a cloud modifies the dynamics of a coalescing…
Ultra-light dark matter (ULDM) is a compelling candidate for cosmological dark matter. If ULDM interacts with ordinary matter, it can induce measurable, characteristic signals in pulsar-timing data because it causes the orbits of pulsars in…
Mirror Dark Matter (MDM) has been considered as an elegant framework for a particle theory of Dark Matter (DM). It is supposed that there exists a dark sector which is mirror of the ordinary matter. Some MDM models allow particle…
Pulsar timing measurements can be used to detect gravitational radiation from massive black hole binaries. The ~106d quasi-periodic flux variations in Sagittarius A* at radio wavelengths reported by Zhao, Bower, & Goss (2001) may be due to…
Pulsars of very different types - isolated objects, and binaries with short- and long-period orbits, white-dwarf and neutron-star companions - provide the means to test both the predictions of general relativity and the viability of…
Dark energy perturbations are expected to modify the evolution of cosmological perturbations, producing different observational effects. We show that these effects can be encoded in a momentum, space and polarization dependent effective…
A binary system embedded in a Dark Matter (DM) background may experience a change in its orbital period due to dynamical friction as the binary moves through a wind of DM particles. We compute such a perturbative effect on the binary…
Binary and Millisecond pulsars have a great deal to teach us about stellar evolution and are invaluable tools for tests of relativistic theories of gravity. Our understanding of these objects has been transformed by large-scale surveys that…
Pulsars in close binary orbit around another neutron star or a massive white dwarf make ideal laboratories for testing the predictions of gravitational radiation and self-gravitational effects. We report new timing measurements of the…
Lensing of one member of a binary by its companion is studied for several classes of binaries. For binaries in which at least one member is an ordinary (non-compact) star, the optical depths to lensing is extremely low, $\tau\lsim…