Probing elastic interactions in the dark sector and the role of 
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We consider two models of interacting dark energy, both of which interact only through momentum exchange. One is a phenomenological one-parameter extension to wCDM, and the other is a coupled quintessence model described by a Lagrangian formalism. Using a variety of high and low redshift data sets, we perform a global fitting of cosmological parameters and compare to ΛCDM, uncoupled quintessence, and wCDM. We find that the models are competitive with ΛCDM, even obtaining a better fit when certain data sets are included.

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“…Whilst this paper was being finalised, the following paper that covers similar topics was added to the arXiv [36].…”

Section: Acknowledgmentsmentioning

confidence: 99%

“…These models leave the background evolution of the Universe unchanged, only affecting the perturbations [17,[29][30][31][32][33][34]. This allows them to fit the CMB data very well, and JCAP08(2022)075 to alleviate the σ 8 tension [19,35,36]. In this work we test two such models using data from the CMB, SNe Ia, BAO, and cluster counts.…”

Section: Introductionmentioning

confidence: 99%

Momentum transfer models of interacting dark energy

Linton

Crittenden

Pourtsidou

2022

J. Cosmol. Astropart. Phys.

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“…Fig. 3 0 The deceleration parameter of this particular IDM model, given by (81), is plotted versus the redshift, by using different data sets, in Fig. (2).…”

Section: B Comparison With the Observational Datamentioning

confidence: 99%

“…Once all relevant cosmological probes are included simultaneously, the value of the Hubble parameter in this model is H 0 = 69.82 +0.63 −0.76 km /(s Mpc ), which reduces the Hubble tension to 2.5 σ. A cosmological scenario where the dark sector is described by two perfect fluids that interact through a velocity-dependent coupling was considered in [81]. The interaction of both dark components leads to a suppression of the dark matter clustering at late times.…”

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confidence: 99%

Observational constraints on the interacting dark energy - dark matter (IDM) model

Harko¹,

Asadi²,

Moshafi³

et al. 2022

Preprint

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Particle creation (or annihilation) mechanisms, described by either quantum field theoretical models, or by the thermodynamics of irreversible processes, play an important role in the evolution of the early Universe, like, for example, in the warm inflationary scenario. Following a similar approach, based on the thermodynamics of open systems, in the present work we investigate the consequences of the interaction, decay, and particle generation in a many-component Universe, containing dark energy, dark matter, radiation, and ordinary matter, respectively. In this model, due to the interaction between these components, and of the corresponding thermodynamical properties, the conservation equations of different cosmological constituents are not satisfied individually. We introduce a thermodynamic description of the Universe, in which two novel physical aspects, the particle number balance equations, and the creation pressures, are considered, thus making the cosmological evolution equations thermodynamically consistent. To constrain the free parameters of the model several observational data sets are employed, including the Planck data sets, Riess 2020, BAO, as well as Pantheon data. By using a scaling ansatz for the dark matter to dark energy ratio, and by imposing constraints from Planck+Riess 2020 data, this model predicts an acceptable value for the Hubble parameter, and thus it may provide a solution to the so-called Hubble tension problem, much debated recently.

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“…Cosmological models where DE and CDM are coupled have been investigated in some works (see, for instance, [24][25][26][27][28][29][30][31]). Among all the plethora of interacting models, there is an interesting group which leave the background cosmology as in the standard model while involving a momentum transfer between two dark fluids [32][33][34][35][36][37][38][39][40][41]. The preservation of the standard model at the background level is an appealing property since we know ΛCDM provides a good fit for most data sets.…”

Section: Introductionmentioning

confidence: 99%

Momentum transfer in the dark sector and lensing convergence in upcoming galaxy surveys

Cardona¹,

Figueruelo

2022

J. Cosmol. Astropart. Phys.

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We investigated a cosmological model that allows a momentum transfer between dark matter and dark energy. The interaction in the dark sector mainly affects the behaviour of perturbations on small scales while the background evolution matches the wCDM solution. As a result of the momentum transfer, these kinds of models help alleviating the σ 8 discrepancy in the standard model, but do not resolve the so-called H 0 tension. We confirm that this is indeed the case by computing cosmological constraints. While our analysis tends to favour σ 8 values lower than in ΛCDM, we do not find evidence for a non-vanishing momentum transfer in the dark sector. Since upcoming galaxy surveys will deliver information on scales and red-shift relevant for testing models allowing momentum transfer in the dark sector, we also carried out forecasts using different survey configurations. We assessed the relevance of neglecting lensing convergence κ when modelling the angular power spectrum of number counts fluctuations C ℓ ij(z,z'). We found that not including κ in analyses leads to biased constraints (≈ 1-5σ) of cosmological parameters even when including information from other experiments. Incorrectly modelling C ℓ ij(z,z') might lead to spurious detection of neutrino masses and exacerbate discrepancies in H 0 and σ 8.

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Probing elastic interactions in the dark sector and the role of S8

Cited by 25 publications

References 128 publications

Momentum transfer models of interacting dark energy

Momentum transfer models of interacting dark energy

Observational constraints on the interacting dark energy - dark matter (IDM) model

Momentum transfer in the dark sector and lensing convergence in upcoming galaxy surveys

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