Once again, the ΛCDM model disappoints.
Over the last decades, tests on the standard model of cosmology, the so-called ΛCDM model, have been widely analysed and compared with many different models for describing dark energy. Modified gravities have played an important role in this sense as an alternative to ΛCDM model. Previous observational data has been always favouring ΛCDM model in comparison to any other model. While statistically speaking, alternative models have shown their power, fitting in some cases the observational data slightly better than ΛCDM, the significance and goodness of the fits were not significantly relevant to exclude the standard model of cosmology.
In this paper, a generalisation of exponential F(R) gravity is considered and compared with ΛCDM model by using the latest observational data. Also some well-known model independent parameterisations for the equation of state (EoS) of dark energy are explored.
These scenarios are confronted with the renewed observational data involving the Pantheon plus datasets of supernovae type Ia, the Hubble parameter estimations, data from the cosmic microwave background and baryon acoustic oscillations, where the latter includes the data provided by Dark Energy Spectroscopic Instrument collaboration.
Results of this analysis suggest that standard exponential F(R) models provide much better fits than ΛCDM model, which is excluded at 4σ. Moreover, the parameterisations of the equation of state suggest a non-constant EoS parameter for dark energy, where ΛCDM model is also excluded at 4σ.
Sergei D. Odintsov, Diego Sáez-Chillón Gómez, German S. Sharov, "Modified gravity/Dynamical Dark Energy vs ΛCDM: is the game over?" arXiv:2412.09409 (December 12, 2024).
3 comments:
pw " That spinors are important is very clear from observational physics: all matter fields are spinor fields. And yet, the word “spinor” doesn’t occur even once in Visions in Quantum Geometry (it occurs in the mini-courses mainly in the technical discussion of the construction of the superstring)."
do you written on preon at pf do you have thought about “spinor” and spinor fields?
what about boson and spinor fields?
I read the post at Not Even Wrong. I don't have any notable things to say about spinors.
are spinors a special "preon"
Post a Comment