%0 Generic %1 visinelli2019revisiting %A Visinelli, Luca %A Vagnozzi, Sunny %A Danielsson, Ulf %D 2019 %K tifr %T Revisiting a negative cosmological constant in light of low-redshift data %U http://arxiv.org/abs/1907.07953 %X Persisting tensions between high-redshift and low-redshift precision cosmological observations suggest the dark energy sector of the Universe might be more complex than the positive cosmological constant of the $Łambda$CDM model, and in particular might have a negative energy density. Motivated by string theory considerations, wherein consistent AdS background are ubiquitous, we explore a scenario where the dark energy sector consists of two components: a negative cosmological constant, with a dark energy component with equation of state $w_\phi$ on top. We test the consistency of the model against low-redshift Baryon Acoustic Oscillation and Type Ia Supernovae distance measurements, assessing two alternative choices of distance anchors: the sound horizon at baryon drag $r_drag$ determined by the Planck collaboration, and the Hubble constant $H_0$ determined by the SH0ES program. We find no evidence for a negative cosmological constant, and mild indications for an effective phantom dark energy component on top. A model comparison analysis performed through the Akaike information criterion reveals the $Łambda$CDM model is favoured over our negative cosmological constant model. While our results are inconclusive, should low-redshift tensions persist with future data, it would be worth reconsidering and further refining our toy negative cosmological constant model.

@misc{visinelli2019revisiting, abstract = {Persisting tensions between high-redshift and low-redshift precision cosmological observations suggest the dark energy sector of the Universe might be more complex than the positive cosmological constant of the $\Lambda$CDM model, and in particular might have a negative energy density. Motivated by string theory considerations, wherein consistent AdS background are ubiquitous, we explore a scenario where the dark energy sector consists of two components: a negative cosmological constant, with a dark energy component with equation of state $w_{\phi}$ on top. We test the consistency of the model against low-redshift Baryon Acoustic Oscillation and Type Ia Supernovae distance measurements, assessing two alternative choices of distance anchors: the sound horizon at baryon drag $r_{\rm drag}$ determined by the \textit{Planck} collaboration, and the Hubble constant $H_0$ determined by the SH0ES program. We find no evidence for a negative cosmological constant, and mild indications for an effective phantom dark energy component on top. A model comparison analysis performed through the Akaike information criterion reveals the $\Lambda$CDM model is favoured over our negative cosmological constant model. While our results are inconclusive, should low-redshift tensions persist with future data, it would be worth reconsidering and further refining our toy negative cosmological constant model.}, added-at = {2019-07-19T08:32:02.000+0200}, author = {Visinelli, Luca and Vagnozzi, Sunny and Danielsson, Ulf}, biburl = {https://www.bibsonomy.org/bibtex/2e7647a100e15516330942a7447ac1445/citekhatri}, description = {Revisiting a negative cosmological constant in light of low-redshift data}, interhash = {4f68ee7eab62948d3ec594e9a16c95dd}, intrahash = {e7647a100e15516330942a7447ac1445}, keywords = {tifr}, note = {cite arxiv:1907.07953Comment: 14 pages, 1 table containing 6 figures}, timestamp = {2019-07-19T08:32:02.000+0200}, title = {Revisiting a negative cosmological constant in light of low-redshift data}, url = {http://arxiv.org/abs/1907.07953}, year = 2019 }