Stochastic gravitational-wave background on large cosmological scales

Abstract

Aim: To formulate a model capable of distinguishing astro-physical from primordial gravitational-wave signals.Methods: We used a biased tracer formalism valid on large cosmological scales to introduce modeling basics and con-nected black holes as sources of gravitational wave signal with dark matter.Results: LTC By deriving the model and using the online tool Code for Anisotropies in the Microwave Background (CAMB), we produced the matter power spectrum and used it to construct the gravitational-wave power spectra as a lin-ear biased tracer. The spectra were generated for different Hubble constants and bias parameter values, showing the difference in the amplitude and scale dependence of the spectra. Conclusion: Gravitational-wave background signals can be used as complementary cosmological probes in data from future gravitational-wave space detectors like Laser Interferometer Space Antenna (LISA) and others.