Prof. Edward L. (Ned) Wright, UCLA: "Tired light models invoke a gradual energy loss by photons as they travel through the cosmos to produce the redshift-distance law. This has three main problems:

1. There is no known interaction that can degrade a photon's energy without also changing its momentum, which leads to a blurring of distant objects which is not observed..." http://www.astro.ucla.edu/~wright/tiredlit.htm

I am not competent enough to comment on the other "main problems" but this particular objection of Ned Wright's is obviously idiotic. "Known" interactions are totally irrelevant. The photon loses energy as it travels through vacuum, and there the interactions are still unknown. "Known" interactions do produce blurring but there is no reason why unknown interactions, as well, should produce it.

Actually photons LOSE SPEED - there is vacuum friction that slows down light and causes the Hubble redshift thereby (in a STATIC universe):

"Indeed, Wilczek began his lecture by speaking of the profound analogy between materials and vacuum. What our naked senses perceive as empty space turns out to be a riotous environment of virtual particles fluorescing and dying away on extremely small scales of space and time, as well as fog-like fields and condensates, which permeate all space and dictate the properties of elementary particles. To give an analogy for this perplexing new picture of reality, Wilczek asks us to imagine intelligent fish in a world surrounded by water. Such creatures would perceive the water surrounding them as their version of empty space or a vacuum. "The big idea I want to convey is simply this: We're like those fish," he said. What our senses perceive as empty space is better understood as a substance, a material." https://asunow..asu.edu/20170208-fin...-frank-wilczek

Paul Davies: "This leads to the prediction of vacuum friction: The quantum vacuum can act in a manner reminiscent of a viscous fluid."x http://philpapers.org/rec/DAVQVN

New Scientist: "Vacuum has friction after all." https://www.newscientist.com/article...tion-after-all

"So how can a vacuum carry force? One of the first things we learn in classical physics is that in a perfect vacuum - a place entirely devoid of matter - friction can't exist, because empty space can't exert a force on objects traveling through it. But, in recent years, quantum physicists have shown that vacuums are actually filled by tiny electromagnetic fluctuations that can interfere with the activity of photons - particles of light - and produce a measurable force on objects." http://www.businessinsider.com/casim...rticles-2017-4

Pentcho Valev