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The standard cosmological model explains redshift as an effect related to gravity; specifically, to the way that the geometry of spacetime influences the properties of light. Through general relativity, we can measure the gravitational effects of matter and energy on redshift over cosmological time. We can see that the relationship between redshift and distance changes over billions of years. It changes in ways that are readily explainable in general relativity and that gives us measurements of the matter and energy in the universe that we can compare with other types of measurements.
Is gravitational red-shift at source taken into account? I haven't found anything to verify that it has.
When observing anything outside of the solar system it will appear blue shifted relative to us. Is this taken into account. When observing anything outside our galaxy, it will appear more blue shifted. Is this taken into account?
Mike - why don't you do the sums - use upper bounds rather than exact masses if you feel the exact masses are compromised by the methods used to calculate them. They are not particularly taxing - and you will then have a rough idea of the magnitude of the shifts involved. With that your questions might have a bit more bite. You see; if the upper bounds of the graviational redshift are orders of magnitudes less that those observed with distant galaxies then we can move on - if they are of the same or similar magnitude then you are right to highlight a problem.
Quasars are frequently used to determine distance. Some quasars (the ones separate from their galaxies) are observed to be many orders of magnitude further away than their parent galaxies according to their red-shift. This would imply that the the red shift of quasars is being wrongly interpreted by orders of magnitude. Not an insignificant amount.
Presumably, to estimate red-shift at source one must estimate the mass of the object but that means knowing the objects distance and for that we use red-shift. See the problem?
Quote from: MikeS on 29/07/2011 13:16:51Quasars are frequently used to determine distance. Some quasars (the ones separate from their galaxies) are observed to be many orders of magnitude further away than their parent galaxies according to their red-shift. This would imply that the the red shift of quasars is being wrongly interpreted by orders of magnitude. Not an insignificant amount.It has already been established that there is a red-shift problem here, a discrepancy of 'orders of magnitude'Quote from: imatfaal on 29/07/2011 16:43:44Mike - do the sums!There is absolutely no point in me doing the maths as there is nothing for me to prove. The problem is known to exist.
Mike - do the sums!
The largest uncertainty is probably that we ignore the fact that the higher frequencies within multi-chromatic white light loose energy faster than the lower frequencies. This tends to bias all multi-chromatic white light toward the red after a few million years of travel through a busy universe.
According to Fermilab, a photon does not loose energy, seehttp://www.fnal.gov/pub/inquiring/questions/red_shift1.html
Quote from: MikeS on 30/07/2011 07:11:16According to Fermilab, a photon does not loose energy, seehttp://www.fnal.gov/pub/inquiring/questions/red_shift1.htmlIt all depends on what it encounters along the way. There is a vast difference between how cosmology looks at the photon; as an indisputably fixed reference, and what optics and radio/radar technology know about the intricacy of electromagnetic radiation.The claim that a photon is unalterable during a million year zigzag journey through a forest of gravitational and electromagnetic fields is a wishful assumption and oversimplification at best.