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    On searches for gravitational waves from mini-creation events by laser interferometric detectors
    (Wiley-Blackwell, 2006-02-27) Sarmah, B. P.; Banerjee, S.K.; Dhurandhar, Sanjeev; et al.
    As an alternative view to the standard big bang cosmology, the quasi-steady-state cosmology argues that the Universe was not created in a single great explosion: it did not have a beginning, nor will it ever come to an end. The creation of new matter in the Universe is a regular feature occurring through finite explosive events. Each creation event is called a mini-bang, or a mini-creation event. Gravitational waves are expected to be generated as a result of any anisotropy present in this process of creation. A mini-creation event that ejects matter in two oppositely directed jets is thus a source of gravitational waves, which can in principle be detected by laser interferometric detectors. In the present work we consider the gravitational waveforms propagated by linear jets and then estimate the response of laser interferometric detectors such as LIGO and LISA.
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    Inhomogeneities in the microwave background radiation interpreted within the framework of the quasi-steady state cosmology
    (American Astronomical Society, 2003-03-01) Narlikar, J. V.; Vishwakarma, R. G.; Hajian, Amir; et al.
    We calcul ate the expected angular power spectrum of the temperature fluctuations in the microwave background radiation (MBR) generated in the quasi–steady state cosmology (QSSC ). The paper begins with a brief description of how the background is produced and thermalized in the QSSC. We then discuss within the framework of a simple model the likely sources of fluctuations in the background due to astrophysical and cosmological causes. Power spectrum peak s at l=6–10, 180–220, and 600–900 are shown to be respectively related in this cosmology to curvature effects at the last minimum of the scale factor, clusters, and groups of galaxies. The effect of clusters is shown to be related to their distribution in space as indicated by a toy model of structure formation in the QSSC. We derive and parameterize the angular power spectrum using six parameters related to the sources of temperature fluctuations at three characteristic scales. We are able to obtain a satisfactory fit to the observational band power estimates of the MBR temperature fluctuation spectrum. Moreover, the values of the best-fit parameters are consistent with the range of expected values .