Ned Wright's best fit standard LCDM is simply one possible concrete version of the usual LCDM model that cosmologists use. It has the normally preferred parameters (0.27, 0.73, 71) plus the estimate that Wright gave of Omega = 1.011.(adsbygoogle = window.adsbygoogle || []).push({});

That's what he gave in January 2007 as the best LCDM fit to some 4 or 5 independent sets of data---currently the best and most complete he could get his hands on.

IMHO the value of having a CONCRETE instance of the standard model is pedagogical. It gives people something definite to think about. So I want to try it out pedagogically.

I will use the 'best fit' universe model in conjuntion with Wright's cosmology calculator---including this new version

http://www.astro.ucla.edu/~wright/DlttCalc.html

this version has the normal parameters (0.27, 0.73, 71) as default values so you don't have to type them in, and it converts light travel time to redshift z.

there is an arbitrary cutoff at 13.666 billion years, at which time the redshift is 999,999,999. that is, according to the calculator, distances have expanded

a BILLION-fold in the past 13.666 billion years.

it is already very crude and naive to be pushing a calculator that far back, and it is good he makes that artificial cut-off because it certainly would not do to try to push it back any farther----but for the sake of concreteness I will use the calculator's numbers back that far.

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# Wright's 'best fit' universe does not expand out into empty space

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