On Recent Claims Concerning the R_h=ct Universe

TL;DR

The paper defends the R_h=ct cosmological model against recent criticisms, demonstrating its consistency with observations and addressing misconceptions about its theoretical foundations.

Contribution

It provides a detailed rebuttal to critiques of R_h=ct, affirming its observational support and clarifying misunderstandings about its theoretical basis.

Findings

R_h=ct outperforms LCDM in multiple cosmological tests

Likelihood of R_h=ct being correct is 90-95% based on data

Criticisms of R_h=ct are based on incorrect assumptions

Abstract

The R_h=ct Universe is a Friedmann-Robertson-Walker (FRW) cosmology which, like LCDM, assumes the presence of dark energy in addition to (baryonic and non-luminous) matter and radiation. Unlike LCDM, however, it is also constrained by the equation of state (EOS) p=-rho/3, in terms of the total pressure p and energy density rho. One-on-one comparative tests between R_h=ct and LCDM have been carried out using over 14 different cosmological measurements and observations. In every case, the data have favoured R_h=ct over the standard model, with model selection tools yielding a likelihood ~90-95% that the former is correct, versus only ~5-10% for the latter. In other words, the standard model without the EOS p=-rho/3 does not appear to be the optimal description of nature. Yet in spite of these successes---or perhaps because of them---several concerns have been published recently regarding the fundamental basis of the theory itself. The latest paper on this subject even claims---quite remarkably---that R_h=ct is a vacuum solution, though quite evidently rho is not 0. Here, we address these concerns and demonstrate that all criticisms leveled thus far against R_h=ct, including the supposed vacuum condition, are unwarranted. They all appear to be based on incorrect assumptions or basic theoretical errors. Nevertheless, continued scrutiny such as this will be critical to establishing R_h=ct as the correct description of nature.