I present here the results of the study of the gravitational radiation generated by the infall (from rest at radius r0) of a point particle of mass m0 into a Schwarzschild black hole of mass M . We use Laplace’s transform methods and find that the spectra of radiation for ∼ 5M < r0 < ∞ presents a series of evenly spaced bumps. The total radiated energy is not monotonically decreasing with r0, b...

Rotating white dwarfs undergoing quasi-radial oscillations can emit gravitational radiation in a frequency range from 0.1 − 0.3 Hz. Assuming that the energy source for the gravitational radiation comes from the oblateness of the white dwarf induced by the rotation, the strain amplitude is found to be ∼ 10 for a white dwarf at ∼ 50 pc. The galactic population of these sources is estimated to be ...

These lectures aim at providing an introduction to the properties of gravitational waves and in particular to those gravitational waves that are expected as a consequence of perturbations of black holes and neutron stars. Imprinted in the gravitational radiation emitted by these objects is, in fact, a wealth of physical information. In the case of black holes, a detailed knowledge of the gravit...

A massive gravitationally bound object with a radius r ≤ 2GM/c 2 , which occurs in the non-singular version of the nonsymmetric gravitational theory (NGT), replaces the black hole in Einstein gravity theory. This object is kept stable by the attractive and repulsive forces generated by NGT, as well as standard matter pressures, and is called a superdense object (SDO). The luminosity of gravitat...

We develop the Polnarev’s analytic method to calculate of the polarization power spectrum of the cosmic microwave background radiation (CMB) due to relic gravitational waves. This approach complements the more precise numerical results by providing insight into the physical origins of the features in the power spectrum. We make use of the WKB approach to handle the evolution of the relic gravit...

The previous discussions have taken place in the context of linearized GR, which is not a fully consistent theory. We will now discuss some aspects of GR in the nonlinear regime, with particular attention to isolated systems. Our eventual goal is to compute the energy loss of a system emitting gravitational waves. We introduced the concepts in the last lecture, and are now ready to proceed to t...

One of the types of signals for which the LIGO interferometric gravitational wave detectors will search is a stochastic background of gravitational radiation. We review the technique of searching for a background using the optimally-filtered cross-correlation statistic, and describe the state of plans to perform such cross-correlations between the two LIGO interferometers as well as between LIG...

We show that gravitational radiation is produced quite efficiently in interactions of classical waves created by resonant decay of a coherently oscillating field. For simple models of chaotic inflation in which the inflaton interacts with another scalar field, we find that today’s ratio of energy density in gravitational waves per octave to the critical density of the universe can be as large a...

The history of astronomy has been that of our measurement of photons from astrophysical objects and, more recently, the early universe (the CMB). Analogously, the universe is thought to be suffused by gravitational radiation — a background from sources in the early universe (e.g., inflation) and “foregrounds” from the gravitational interaction of massive astrophysical objects, such as the massi...