INTERACTION BETWEEN DARK ENERGY AND DARK MATTER: OBSERVATIONAL CONSTRAINTS FROM OHD, BAO, CMB AND SNe Ia

Abstract

In order to test if there is energy transfer between dark energy and dark matter, we investigate cosmological constraints on two forms of nontrivial interaction between the dark matter sector and the sector responsible for the acceleration of the universe, in light of the newly revised observations including OHD, CMB, BAO and SNe Ia. More precisely, we find the same tendencies for both phenomenological forms of the interaction term Q = 3γHρ, i.e., the parameter γ to be a small number, |γ| ≈ 10 −2 . However, concerning the sign of the interaction parameter, we observe that γ > 0 when the interaction between dark sectors is proportional to the energy density of dust matter, whereas the negative coupling (γ < 0) is preferred by observations when the interaction term is proportional to dark energy density. We further discuss two possible explanations to this incompatibility and apply a quantitative criteria to judge the severity of the coincidence problem. Results suggest that the γmIDE model with a positive coupling may alleviate the coincidence problem, since its coincidence index C is smaller than that for the γ d IDE model, the interacting quintessence and phantom models by four orders of magnitude.

New observational constraints on f(T) cosmology from radio quasars

“…It is obvious that the quasar data, when combined to CMB and BAO observations, can give more stringent constraints on this f (T ) cosmology, which demonstrates the strong constraining power of BAO and CMB on the cosmological parameters. This situation has also been extensively discussed in previous work investigating dark energy scenarios with other astrophysical observations [46][47][48][49][50]. Again, the constraining power of 120 quasar data is comparable to that of 580 SN Ia.…”

Constraints on interacting dark energy from time delay lenses

“…We note that compared to the constraint with SN, the gravitational lenses shift the best-fit to a larger value for the dark energy EoS parameter w x and a positive coupling between DE and DM (γ x = 0.003 +0.013 −0.013 with D ∆t + BAO + CMB). In addition, the constraining results in this work with joint observational data including D ∆t are essentially the same in comparison to the results of Cao et al (2013), 85 which incorporate combined observations including the 28 H(z) measurements from the differential ages of redenvelope galaxies as well as the BAO peaks. However, we remark here that, from Fig.…”

“…This is noted by using the 182 Gold SNIa together with CMB and large-scale structure for the interacting holographic DE model 43 and by using the revised Hubble parameter data together with CMB and BAO. 85 In order to illustrate the impact of SGL data, we also show the cosmological constraints from the combination of SN+BAO+CMB without D ∆t and D ∆t + CMB+BAO without SN in Fig. 1.…”

The generalized cosmic equation of state: a revised study with cosmological standard rulers

“…The advantage of this data set, compared with other standard rulers including baryon acoustic oscillations (BAO) [43][44][45][46], galaxy clusters [47] and strong lensing systems [48][49][50][51][52][53], is that quasars are observed at much higher redshifts (z ∼ 3.0). However, in order to consider the redshift coverage of observations and break the degeneracy of the model parameters, we also add, in our discussion, the angular diameter distance measurements from galaxy clusters, BAO and CMB, which have been extensively used to probe the nature of cosmic acceleration in much previous work [54][55][56][57].…”