Discussion:
What Causes the Hubble Redshift (in a Static Universe)
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Pentcho Valev
2017-02-08 20:12:29 UTC
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https://asunow.asu.edu/20170208-finding-nothing-conversation-frank-wilczek
"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."

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

https://www.newscientist.com/article/mg20927994.100-vacuum-has-friction-after-all
New Scientist: "Vacuum has friction after all."

The Hubble redshift is due to the property of vacuum to slow down light - an effect analogous to slowing down moving objects by friction. The idea that vacuum constituents can slow down light is largely discussed, but only in a quantum gravity context:

http://backreaction.blogspot.fr/2017/01/what-burst-fresh-attempt-to-see-space.html
Sabine Hossenfelder: "It's an old story: Quantum fluctuations of space-time might change the travel-time of light. Light of higher frequencies would be a little faster than that of lower frequencies. Or slower, depending on the sign of an unknown constant. Either way, the spectral colors of light would run apart, or 'disperse' as they say if they don't want you to understand what they say. Such quantum gravitational effects are miniscule, but added up over long distances they can become observable. Gamma ray bursts are therefore ideal to search for evidence of such an energy-dependent speed of light."

It is time to start discussing the parallel idea: that slowing down light by vacuum constituents produces the Hubble redshift (in a STATIC universe):

http://www.nature.com/news/superfluid-spacetime-points-to-unification-of-physics-1.15437
Nature: "As waves travel through a medium, they lose energy over time. This dampening effect would also happen to photons traveling through spacetime, the researchers found."

For not so distant stars the slowing down of light is expressed as Hubble redshift but beyond a certain distance the star light does not reach us at all (Olbers' paradox).

Pentcho Valev
Pentcho Valev
2017-02-09 09:12:28 UTC
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Theoretical physics should be deductive, which means that theoreticians should regularly try to draw conclusions from premises (postulates) that are not certain to be true. In my view, it makes sense to see what cosmology can be deduced from the following two simple postulates (additional premises will be needed of course):

Postulate 1. Once emitted, light never changes its wavelength.

Postulate 2. The following relation is always valid for any observer:

(frequency) = (speed of light)/(wavelength)

The two postulates establish a universal proportionality between measured frequency and (difficult to measure) speed of light.

A few years ago I tried to develop the idea for a FQXi essay contest. Now I don't find my essay well written, and there is a mistake in it concerning Einstein's interpretation of the variability of the speed of light in a gravitational field, but still some arguments could be useful:

http://fqxi.org/data/essay-contest-files/Valev_Shift_in_Frequency_Im.pdf
Pentcho Valev, Shift in Frequency Implies Shift in Speed of Light, FQXi essay contest, 2012 − Questioning the Foundations: Which of our basic physical assumptions are wrong?

Pentcho Valev
Pentcho Valev
2017-02-10 19:47:28 UTC
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http://www.nature.com/news/superfluid-spacetime-points-to-unification-of-physics-1.15437
Nature: "As waves travel through a medium, they lose energy over time. This dampening effect would also happen to photons traveling through spacetime, the researchers found." x

http://www.eleceng.adelaide.edu.au/thz/documents/davies_2001_cha.pdf
Paul Davies: "As pointed out by DeWitt, the quantum vacuum is in some respects reminiscent of the aether, and in what follows it may be helpful to think of space-time as filled with a type of invisible fluid medium, representing a seething background of vacuum fluctuations. Although the mechanical properties of this medium can be strange, and the image should not be pushed too far, it is sometimes helpful to envisage this "quantum aether" as possessing a type of viscosity."

HYPOTHESIS: As the photon travels through the viscous vacuum (in a STATIC universe), it loses speed analogously to a golf ball losing speed due to the resistance of the air.

On this hypothesis the resistive force (Fr) is proportional to the velocity of the photon (V):

Fr = - KV

That is, the speed of light decreases with time in accordance with the equation:

dV/dt = - K'V

Clearly, at the end of a very long journey of photons (coming from a very distant object), the contribution to the redshift is much smaller than the contribution at the beginning of the journey. Light coming from nearer objects is less subject to this effect, that is, the increase of the redshift with distance is closer to LINEAR for short distances. For distant light sources we have:

f' = f(exp(-kt))

where f is the initial and f' the measured (redshifted) frequency. (It is assumed that the speed of light and the frequency vary while the wavelength remains unchanged.) For short distances the following approximations can be made:

f' = f(exp(-kt)) ~ f(1-kt) ~ f - kd/λ

where d is the distance between the light source and the observer and λ is the wavelength. The equation f'=f-kd/λ is only valid for short distances and corresponds to the Hubble law. The equation f'=f(exp(-kt)) shows that, at the end of a very long journey (in a STATIC universe), photons redshift much less vigorously than at the beginning of the journey. This provides an alternative explanation of the observations that brought the 2011 Nobel Prize for Physics to Saul Perlmutter, Adam Riess and Brian Schmidt.

Pentcho Valev
Pentcho Valev
2017-02-13 21:38:43 UTC
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Victorious Einsteinians:

http://www.sciencemag.org/news/2001/06/tired-light-hypothesis-gets-re-tired
"Both the standard expanding-universe and the tired-light theory, they realized, agree that redshifted light should make distant galaxies look dimmer than they really are. In an expanding universe, however, time dilation and other relativistic distortions will also dim distant galaxies, making them appear much fainter than tired-light theory dictates. What's more, young stars - and thus young galaxies - tend to be considerably brighter than old ones. When that extra brightness is taken into account, the observations match expanding-universe predictions, as Lubin and Sandage will report in Astronomical Journal. For the tired-light theory to be correct, young galaxies would have to be dimmer, rather than brighter, than old ones. "The expansion is real. It's not due to an unknown physical process. That is the conclusion," says Sandage. Although not surprising in themselves, the results are useful for "tidying things up in our cosmology," says Michael Pahre, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. Even so, "I don't think it's possible to convince people who are holding on to tired light," says Ned Wright, an astrophysicist at the University of California, Los Angeles. "I would say it is more a problem for a psychological journal than for Science."

The arguments are idiotic (not even wrong), and Einsteinians also suggest that any supporter of the tired-light hypothesis is a psychopath. Needless to say, in the end heretics would rather start believing the relativistic idiocies than see themselves kicked out of universities as psychopaths:

https://ebooks.adelaide.edu.au/o/orwell/george/o79n/chapter1.7.html
"In the end the Party would announce that two and two made five, and you would have to believe it. It was inevitable that they should make that claim sooner or later: the logic of their position demanded it. Not merely the validity of experience, but the very existence of external reality, was tacitly denied by their philosophy. The heresy of heresies was common sense. And what was terrifying was not that they would kill you for thinking otherwise, but that they might be right. For, after all, how do we know that two and two make four? Or that the force of gravity works? Or that the past is unchangeable? If both the past and the external world exist only in the mind, and if the mind itself is controllable what then?"

Pentcho Valev

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