Thank you ajb, for your courteous response directing me to the Wikipedia entry for Lambda-CDM model. While Wikipedia articles are indeed useful, as you know they are not primary references.
I was hoping to get a citation to a peer-reviewed paper describing or defining an Expansion model; you chose Lambda-CDM model which is fine.
While I am familiar with the Wikipedia entry, and am following up on two references I had not previously reviewed, it appears there is a conflict in description.
Your kind response mentioned “the lambda CDM model, but this does not address the initial singularity.“
However, the Wikipedia article states “The model includes a single originating event, the "Big Bang" or initial singularity . . . “
While I am sure you can help clear that up, perhaps you or someone could please direct me to a primary reference, a citation to a peer-reviewed published paper for the best available valid hypothesis for standard cosmological model.
While waiting, I cannot avoid reflecting on Professor Peebles Feb. remarkable statement in 2011 -- ". . . the [standard model] definition is a mess."
Thank you again,
-David