“Our results highlight that a unified dark fluid with evolving equation of state and null sound speed is sufficient to pass current constraints without invoking a phantom component.”

The paper

The paper's details are OpenAlex's; the citation count is OpenAlex's, 15 Oct 2026.

The story so far

1. 1

   What has been checked on Ecdysis

   Exuvia registered the claim on 15 October 2026, with a test written from the paper. No check has been filed yet.

What would check it

How far it has been checked

1. 1
   The object itself, checked againverification · not yet

   Not yet: re-run the paper's analysis on its own data, where the authors have published it.

2. 2
   New instances of the constructionreproduction · not yet

   Not yet: the same construction run afresh.

3. 3
   The designrobustness tests and arguments · not yet

   Nothing yet: change the method or the data and see whether it holds (a robustness test), or argue that the method does not test what the claim says.

How sure is the record?

Share this finding

Ready-made posts, written from the record. You post them yourself, from your own account; nothing is ever posted for anyone.

Click a post's text to select all of it. Both posts give the claim's standing on the record, and the longer one says what the checks show and what they do not; the wording changes when the record does. To cite the claim, see Cite this claim.

What would prove it wrong

Refuted if a statistically significant (≥95% confidence) joint analysis of current cosmological data sets demonstrates that no UDF model with cs^2 = 0 and w(z) ≥ –1 across the redshift range 0 < z < 3 can achieve a χ² improvement comparable to or better than ΛCDM (or CPL) within its allowed parameter space, as quantified by Δχ² ≤ 0.5 relative to the best‑fit ΛCDM model.

The test as Exuvia registered it on 15 Oct 2026, written from the paper's words.

The wider literature

Earlier work it rests on, as the citing paper says

• uncheckedWithout the need for specific code by the user, interdependencies between different stages of a model pipeline are exploited for sampling efficiency: intermediate results are automatically cached, and parameters are gro…takes its method from, as the citing paper says · from the literature · identified by Exuvia: “We ran Monte Carlo Markov Chains (MCMC) using the Cobaya Torrado and Lewis (2019); Torrado and Lewis (2021) sampler, and minimized the likelihood to compute th…”
• uncheckedWith 18 peaks in the temperature and polarization angular power spectra constrained well, Planck measures five of the six parameters to better than 1% (simultaneously), with the best-determined parameter (theta_*) now k…takes its method from, as the citing paper says · from the literature · identified by Exuvia: “Figure 1 shows the evolution of the equation of state of the UDF as a function of scale factor, using the best-fit values for w_{0} , w_{a} and \Omega_{c} obta…”
• uncheckedThe low-multipole 100x143 GHz EE cross-spectrum constrains the reionization optical-depth parameter $τ$ to better than 15% (in combination with with the other low- and high-$\ell$ likelihoods).takes its method from, as the citing paper says · from the literature · identified by Exuvia: “We did not include low- \ell polarization spectra but imposed a Gaussian prior on the optical depth \tau with \sigma(\tau)=0.0073 Planck Collaboration et al. (…”
• uncheckedA combined analysis gives dark matter density Ω c h 2 = 0.120 ± 0.001, baryon density Ω b h 2 = 0.0224 ± 0.0001, scalar spectral index n s = 0.965 ± 0.004, and optical depth τ = 0.054 ± 0.007 (in this abstract we quote…takes its method from, as the citing paper says · from the literature · identified by Exuvia: “We did not include low- \ell polarization spectra but imposed a Gaussian prior on the optical depth \tau with \sigma(\tau)=0.0073 Planck Collaboration et al. (…”
• uncheckedIncluding Planck CMB data, SDSS BAO data, and DES $3\times2$-point data gives $(Ω_{\rm M},w)=(0.321\pm0.007,-0.941\pm0.026)$.takes its method from, as the citing paper says · from the literature · identified by Exuvia: “Figure 1 shows the evolution of the equation of state of the UDF as a function of scale factor, using the best-fit values for w_{0} , w_{a} and \Omega_{c} obta…”