Lambda-CDM model
The standard model of cosmology, the Lambda-CDM model, assumes the Copernican principle and the more general Cosmological principle. The Lambda-CDM model's observations are largely consistent, but there remain unsolved problems. Some cosmologists and theoretical physicists have created models without the Cosmological or Copernican principles to constrain the values of observational results, to address specific known issues, and to propose tests to distinguish between current models and other possible models.