We evaluate and compare the gravitational wave and density perturbation contributions to the cosmic microwave background radiation, on the basis of the same power law inflationary model. The inflation to radiation transition is treated in this paper as instantaneous, but a model is constructed to allow for a smooth transition from the radiation to the matter dominated eras. The equations are nu...

We extend the formalism of the relativistic thermal and kinematical SunyaevZeldovich effects to the observer’s system (the Solar System) moving with a velocity ~ βS ≡ ~vS/c with respect to the cosmic microwave background radiation. We confirm the results recently obtained by Chluba, Huetsi, and Sunyaev in the lowest order of the observer’s velocity βS. We give a more general analytic expression...

We study a time-dependent and spherically-symmetric solution with a star-like source. We show that this solution can be interpreted as an exterior solution of a contracting star which has a decreasing temperature and is immersed in a homogenous and isotropic background radiation. Distribution of the temperature in the fields and close-to Schwarzschild approximation of the solution are studied. ...

We reexamine the interaction of ultra high energy nuclei with the microwave background radiation. We find that the giant dipole resonance leaves a new

After a short history of the Λ-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance-physics, corresponding to an energy scale of at least 100 GeV. The actual tiny value of the cosmological constant in any natural scale of units represents, therefore, one of the deepest mysteries of present day fundamental physics. We also briefly...

Data taken with the HEGRA Scintillator Array within 2.5 years have been used to search for spatial anisotropies in the arrival directions of cosmic rays (E > 20 TeV). For this purpose partial sky survey maps are produced, carefully taking the detector response and changing conditions in the atmosphere into account. In this paper, results on the search for TeV –emission correlated with the Galac...

We discuss the local density fluctuations which arise due to the topological defects that appear after the phase transition of light pseudo-Goldstone bosons. It has been found that in a post-inflationary universe the fluctuations of these defects at large scales may have led to galaxy formation, while being consistent with the measurements of the cosmic microwave background radiation. Here we s...

High-energy emission from gamma-ray bursts (GRBs) can give rise to pair echos, i.e. delayed inverse Compton emission from secondary e pairs produced in γ − γ interactions with intergalactic background radiation. We investigate the detectability of such emission with modern-day gamma-ray telescopes. The spectra and light curves are calculated for a wide range of parameters, applying the formalis...

The amplitudes of peaks in the angular power spectrum of anisotropies in the microwave background radiation depend on the mass content of the universe. The second peak should be prominent when cold dark matter is dominant, but is depressed when baryons dominate. Recent microwave background data are consistent with a purely baryonic universe with Ωm = Ωb and ΩΛ ≈ 1. Subject headings: cosmic micr...

Recently funded satellites will map the cosmic microwave background radiation with unprecedented sensitivities and angular resolutions. Assuming only primordial adiabatic scalar and tensor perturbations, we evaluate how accurately experiments of this type will measure the basic cosmological parameters Ω (the total density of the Universe), Ωb (the baryon density), h (the Hubble constant), and Λ...