Reconciling the cosmic age problem in the $$R_\mathrm{h}=ct$$ R h = c t universe

Abstract

Many dark energy models fail to pass the cosmic age test. In this paper, we investigate the cosmic age problem associated with nine extremely old Global Clusters (GCs) and the old quasar APM 08279+5255 in the R h = ct universe. The age data of these oldest GCs in M31 are acquired from the Beijing-Arizona-Taiwan-Connecticut system with up-to-date theoretical synthesis models. They have not been used to test the cosmic age problem in the R h = ct universe in previous literature. By evaluating the age of the R h = ct universe with the observational constraints from the type Ia supernovae and the Hubble parameter, we find that the R h = ct universe can accommodate five GCs and the quasar APM 08279+5255 at redshift z = 3.91. But for other models, such as CDM, the interacting dark energy model, the generalized Chaplygin gas model, and holographic dark energy model, cannot accommodate all GCs and the quasar APM 08279+5255. It is worthwhile to note that the age estimates of some GCs are controversial. So, unlike other cosmological models, the R h = ct universe can marginally solve the cosmic age problem, especially at high redshift.

Subluminal Cosmology

“…First we have presented our subluminal model only as a possibility of thinking. The model of Melia [2]- [20] is actually flat, but in some cases it is consistent with our spatially positively curved model. Thus, we are encouraged to present our proposal as a realistic model.…”

Fluorescent Metallic Nanoclusters: Electron Dynamics, Structure, and Applications

“…It has been demonstrated that the loading of the ultrasmall Au NCs onto TiO 2 nanocrystals results in strong visible light absorption and signifi cantly increased visible light photocatalytic activity for water splitting or hydrogen generation. [ 132 ] Similarly, Au NCs loading onto BaLa 4 Ti 4 O 15 leads to signifi cantly enhanced visible light photocatalytic activity. [ 133 ] Moreover, Amal and co-workers [ 134 ] investigated the improvement of photocatalytic performance of TiO 2 by mixing metal cluaters.…”

Whispering Gallery Mode Optical Microresonators: Structures and Sensing Applications

“…With the continuous improvement of WGMRs in optical sensing, many novel geometric structures have appeared in recent years, such as: microdisk, [17,[116][117][118][119][120][121][122][123][124][125] microbubble, [126][127][128][129][130][131][132] microbottle, [133][134][135][136][137][138][139][140][141][142][143][144][145][146][147] microtube, [148][149][150][151][152][153][154][155][156][157][158][159][160] microcylinder, [161][162][163] etc. These new resonators are widely used in the field of phy...…”