Do we live in a steady state Einsteinian Universe or expanding TGD Universe?

The title of the popular article "Universe is Not Expanding After All, Controversial Study Suggests" is quite provocative. The article tells about the findings of Lerner et al described in the article "UV surface brightness of galaxies from the local universe to z ≈ 5". These findings challenge the notion of cosmic expansion.

First some basic concepts. Luminosity P is the total power of electromagnetic radiation emitted by the source per time. The total power dP/dΩ× ΔΩ measured by an instrument spanning a solid angle Δ Ω weakens like 1/d² with distance. Bolometric surface brightness (SB) refers to the total radiation power per area at source and is SB=d²P/dSdΩ=(dP/dΩ)/S, that is dP/dΩ divided by the area S of the source.

The general relativity (GRT) based cosmology predicts that the luminosity decreases as (1+z)^-4 and therefore very rapidly. One factor of (1+z)^-1 comes from the time dilation reducing the emission rate. Second factor (1+z)^-1 comes from the cosmic redshift. A factor (1+z)^-2 comes from the fact that the apparent size as the area spanned by the source has decreased since the emission by cosmic expansion so that the apparent size is now by a factor (1+z)² larger at the moment of emission. If the cosmic redshift is caused by some other mechanism instead of expansion so that one has steady state cosmology, one has much weaker (1+z)^-1 dependence.

The findings of Lerner et al however suggest that the SB for identical spiral galaxies depends only weakly on the distance of the source. In the Einsteinian Universe this favors the steady state Universe. This is in conflict with the recent view of cosmology having a strong empirical support.

In the TGD Universe, galaxies are nodes of a network formed from cosmic strings thickened to flux tubes. The light from the galaxy from A to B travels only along the flux tubes connecting the source to the receiver. These flux tubes can stretch but the amount of light arriving B remains the same irrespective of distance. In Einsteinian space-time this kind of channeling would not happen and the intensity would decrease like 1/distance squared.

This mechanism would give rise to a compensating factor (1+z)² so that the dependence of the BS on redshift would be (1+z)^-2, while the BS in the static Einsteinian Universe would be (1+z)^-1. For z ≈ 5, the TGD prediction for BS is by by a factor of 1/6 smaller than for static Universe whereas the GRT prediction is by a factor 1/196 smaller. TGD prediction is nearer to steady state Universe than expanding Universe based on Einsteinian view about space-time.

The article at TGD view of the engine powering jets from active galactic nuclei provides a model for how galactic jets would correspond to this kind of flux tube connections. See also the articles Cosmic string model for the formation of galaxies and stars and TGD view about quasars.

For a summary of earlier postings see Latest progress in TGD.

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