An alternative model in which the universe is 26.7 billion years old and needs neither dark matter nor dark energy has held up against several major cosmology tests, according to a new University of Ottawa study. The research, titled “A Big Bang Nucleosynthesis Consistency Test of the CCC+TL Cosmology,” is published in the journal Universe.

During 2025 and 2026, Rajendra Gupta, adjunct professor in uOttawa’s Department of Physics, and postdoctoral researcher Dr. Nikolaos Samaras tested the CCC+TL model against a range of important astronomical observations.

CCC+TL stands for “covarying coupling constants plus tired light.” The model suggests that what is usually attributed to dark matter and dark energy could instead come from evolving fundamental constants that govern how forces and particles interact.