Creation Moment 7/31/2024 - A New Cosmology SERIES: Comparing the Predictions

  I am the LORD that maketh all things; 

that stretcheth forth the heavens alone; 

that spreadeth abroad the earth by Myself; 

That frustrateth the tokens of the liars, 

and maketh diviners mad;

 that turneth wise men backward, 

and maketh their knowledge foolish; 

Isaiah 44:24,25

"With these equations, if we know the true size and luminosity of a galaxy, we can compute its angular diameter and apparent brightness at any given redshift for each model. 

Unfortunately, we don’t know a priori the true size or luminosity of a distant galaxy. 

However, we can consider the typical size and luminosity of a nearby galaxy, compute its angular diameter and apparent brightness at a high redshift, and see if distant galaxies at that redshift have comparable angular diameters and brightnesses. This assumes that distant galaxies are comparable to nearby ones—a complication we will deal with below. 

Q: But what is a typical diameter and luminosity of a galaxy?

Let us start by considering a typical diameter. 

Of the ~30 main, confirmed members of the local group of galaxies, the average diameter is around 5,000 parsecs. The median is only 1,350 parsecs due to the fact that small, dwarf galaxies vastly outnumber the larger ones. Since these smaller galaxies tend to be fainter, they will be under-represented in magnitude-limited surveys like the JWST deep fields. Therefore, it makes sense to use a value closer to the mean as an example of a typical galaxy. We will use 4,500 parsecs as a typical galaxy diameter. The exact value is not important since the different models predict different slopes in angular diameter as a function of redshift.

We see the angular diameter of a 4.5 kpc galaxy at various redshifts

for the three models. The red curve is the angular diameter predicted by the ΛCDM model. Notice that the angular diameter reaches a minimum of about 0.5 arcseconds at a redshift of around 1.6, and is larger for greater redshifts. This magnification effect exists only in expanding-space cosmological models. The predicted angular diameter of the tired light model is shown in green (Lovyagin et al. 2022). 

The angular diameter predicted by the Doppler model is shown in black. 

When we examine the angular sizes of images in JWST data, we expect considerable scatter since galaxies come in a range of sizes. But the median should be approximately centered on the curve of the correct model." 

AIG