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Did the dark energy always have a large Compton wavelength?

Bruce A. Bassett·Martin Kunz·David Parkinson·Carlo Ungarelli
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Abstract

Until now all well-studied dark energy models proposed have very large Compton wavelengths, $λ_c > 100 Mpc$ at all time and hence show no clustering on small scales. Evidence against this would disfavour both $Λ$CDM and quintessence. We show however, that large $λ_c$ is actually favoured by current CMB, LSS and SN1a data by comparing quintessence with a condensate scenario with the same background dynamics. The condensate scenario has a very small $λ_c$ before making a transition to negative pressure and large $λ_c$ and therefore exhibits a rich CMB phenomenology which roughly interpolates between $Λ$CDM and flat CDM models.

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Bruce A. Bassett, Martin Kunz, David Parkinson, Carlo Ungarelli. 2002-11-15. Did the dark energy always have a large Compton wavelength?. https://arxiv.org/abs/astro-ph/0210640

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