Abstract
We present observational constraints on the coupling between dark components of anisotropic Bianchi type I universe. We assume interaction between dark matter and dark energy, and split the continuity equation with the inclusion of interaction term F in two scenarios: (i) when coupling between dark components is constant and (ii) when it is a function of redshift (z). We utilize Metropolis-Hastings algorithm to perform Monte Carlo Markov Chain (MCMC) analyses of the models by using observational Hubble data from cosmic chronometers (CC) technique, cosmic microwave background (CMB), baryon acoustic oscillation (BAO), Pantheon compilation of Supernovae type Ia (SNIa), and a Gaussian prior on the Hubble parameter H0. We find that the combination of all databases plus H0 prior gives stringent constraints on the coupling parameter, viz., -0.001 < a < 0.041 in the constant coupling model and -0.042 < a0 < 0.053 in varying coupling model, both at 68% CL. In general, for both models, we find coX approximate to -1 and a(a0) approximate to 0, which indicate that observational data favor ACDM model with null interaction among the dark sector components. In the constant coupling model, our estimations show that (H0 = 73.9+1.5-0.95, a = 0.023+0.017 such a high value of Hubble constant requires the significant value of coupling parameter a. (c) 2022 Elsevier B.V. All rights reserved.