Components of cosmic background radiation and their interaction with matter

Two competing theories proposed to explain the newly observed background radiation at submillimeter wavelengths-emission of dust and radiative decay by weakly interacting particles are explored, emphasizing their possible implications on formation of structures in the early universe. It was discovered that the radiative instability resulting from interaction between dust and radiation cannot grow significantly to form galaxies and large-scale structures. Decaying particle models were shown to explain both the submillimeter background and the recently observed isotropic infrared background radiation at 1 to 5 microns. In addition, non-uniform distribution of decaying particles prior to their decay may act as sources of radiative blastwaves that could provide seeds for galaxy formation. It was shown that within the framework of decaying particle models proposed to account for both the submillimeter and infrared background, galaxy formation may occur as a result of the fragmentation of the bubbles swept up by radiation pressure originating from radiative decay