How and how much does is the cosmological red shift affected?

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SUMMARY

The discussion focuses on the effects of gravitational redshift and motion on the observed redshift of light from distant astronomical sources. It establishes that the redshift is influenced by the local galactic gravitational well and the motion of the observer relative to the galaxy. The typical velocities of 200 km/s lead to a linear frequency shift, while gravitational effects, particularly near black holes, introduce a quadratic shift. The discussion references an article that explains various forms of redshifts in an accessible manner.

PREREQUISITES
  • Understanding of gravitational redshift
  • Familiarity with linear and quadratic frequency shifts
  • Basic knowledge of astronomical velocities (e.g., 200 km/s, 300 km/s)
  • Awareness of black hole physics and its effects on light
NEXT STEPS
  • Research gravitational redshift and its implications in astrophysics
  • Explore the relationship between velocity and frequency shifts in light
  • Study the effects of black holes on light and gravitational waves
  • Read the article on redshift and expansion linked in the discussion
USEFUL FOR

Astronomers, astrophysicists, and students interested in the effects of gravity on light and the dynamics of cosmic observations.

LuckyNate
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When we look out into deep space we see a red shift in the light from distant sources because they are more or less all receding from us. How is the red shift distorted by passing through our local galactic gravitational well, before hitting us down here on the ground?(more red/more blue/no change) How acute is the impact of this effect?

Please say it so it's easy for me to read, I'm not a mathematician.
 
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More blue for the gravitational potential, and depending on the direction for our motion through the galaxy.
The same effect size is present at the source, if it is within a galaxy.

To estimate the effect sizes:
The motion relative to the galaxy leads to a linear frequency shift. Typical velocities are 200km/s, so the relative shift is ##\frac{200 km/s}{300,000km/s} = \frac{1}{1500}##. We know our own velocity relative to our galaxy, this can be taken into account. The motion of the source depends on the type of source.

Gravitational effects are quadratic in the velocity. Typical escape velocities are 300km/s, so the relative shift is ##\frac{(300 km/s)^2}{(300,000km/s)^2} = \frac{1}{1,000,000}##. This corresponds to a really tiny velocity difference (<1km/s).

This gets different if you observe matter very close to a black hole. There, gravitational redshift (together with the motion of the objects) is important.
 
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To go along with mfb's reply this thread has an article covering the various forms of redshifts and causes.

Its written in a easy to understand manner just scroll down to the Redshift and expansion article

https://www.physicsforums.com/showthread.php?t=705427
 
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