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What's the role of stellar interference in redshifts?

  1. May 2, 2013 #1
    So if there are as many galaxies in the Universe as is claimed what's the role of interstellar combination of light waves on the view of the sky we get here on Earth?
     
  2. jcsd
  3. May 2, 2013 #2

    Chronos

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    Enlighten me, what is interstellar combination of light waves?
     
  4. May 3, 2013 #3
    I was thinking just the combination of red shifts with blue shifts next to them like if you're looking at a supernova. So the question could be specified more to be what's the role of gravitational lensing on the apparent magnitudes of supernovae to start with. Then we could pander through more accepted effects to get a better discussion going perhaps?
     
  5. May 3, 2013 #4
    Sounds like your interested in the spectrography aspects. If so various details such as composition. Momentum etc can be derived from spectrometry
     
  6. May 3, 2013 #5
    Interesting thing towards the momentum part of spectrography though I thought spectroscopy was kinda what I was getting to too > different gravitational strengths might give the same spectrographic result right? How do the wavelengths of the red part of the spectrum change given distance to source? Is that a feasible mathematical model as a derivative or is there a gaussian distributive result for that or is that a phenomenon that's new?
     
  7. May 3, 2013 #6
    Unfortunately there is no short and sweet answer to your question. Which I take to mean roughly

    "how does one separate the collection of frequencies one would measure to gather the individual measurements and account for the different redshift adjustments."

    First off I'll post the article myself and other PF members wrote to cover each aspect of redshift and cosmic distance ladder.

    https://www.physicsforums.com/showpost.php?p=4370154&postcount=10


    this article is a slide show however it covers at page 167 apparent magnitude and spectrograph relations.

    http://terrytao.files.wordpress.com/2010/10/cosmic-distance-ladder.pdf

    the page referenced above is better defined here

    http://en.wikipedia.org/wiki/Hertzsprung–Russell_diagram

    the key point is when we gather a collection of varying frequencies in measurements there are numerous steps and processes needed to go through.
    The use of Cepheid (standard candles) are extremely important as many of their properties are well known so we can eliminate many of those steps described in the cosmic distance ladder slide.

    this site has a decent coverage and lab of each aspect of the cosmic distance ladder and the spectrogram usage.

    http://astro.unl.edu/naap/distance/distance.html

    hope this answers your questions or at least helps in defining your specific aspect your looking for

    edit: as far as this being done through a gravitational lens relies on understanding the distortions caused by the lens
    A key point to remember is due to no one method being reliable, scientist rely upon a database of previously collected results and methodologies
     
    Last edited: May 3, 2013
  8. May 3, 2013 #7

    Chronos

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    Gravitiational lensing has no affect on the frequency of lensed photons. Gravitational blueshift only occurs for photons entering a gravitational well. When they exit the gravity well they redshift back to their original frequency.
     
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