What's the role of stellar interference in redshifts?

In summary, the conversation discusses the role of the interstellar combination of light waves on the view of the sky on Earth. This includes factors such as gravitational lensing and spectrography. The use of standard candles, such as Cepheid variables, is important in eliminating unnecessary steps in the cosmic distance ladder. Gravitational lensing does not affect the frequency of lensed photons. Instead, scientists rely on a database of previously collected results and methodologies to understand the distortions caused by the lens.
  • #1
Neuvotonian
5
0
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?
 
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  • #2
Enlighten me, what is interstellar combination of light waves?
 
  • #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?
 
  • #4
Sounds like your interested in the spectrography aspects. If so various details such as composition. Momentum etc can be derived from spectrometry
 
  • #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?
 
  • #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=10this 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
 
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  • #7
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.
 

What is stellar interference?

Stellar interference refers to the effect of stars on the measurement of redshifts of galaxies. It is caused by the light from stars being included in the spectrum of light from the galaxy being studied, which can alter the measurements of the galaxy's redshift.

How does stellar interference affect redshift measurements?

Stellar interference can impact redshift measurements by introducing noise and altering the shape of the galaxy's spectrum. This can make it difficult to accurately determine the redshift of the galaxy and can lead to erroneous conclusions about its distance and movement.

What techniques are used to correct for stellar interference?

There are several techniques used to correct for stellar interference, including subtracting the spectrum of the stars from the spectrum of the galaxy, using statistical methods to filter out the noise caused by the stars, and using advanced algorithms to isolate the galaxy's spectrum from the rest of the data.

Why is it important to account for stellar interference in redshift measurements?

It is crucial to account for stellar interference in redshift measurements because it can significantly impact our understanding of the universe. Redshift measurements are used to determine the distance and movement of galaxies, which are essential for studying the expansion of the universe and the evolution of galaxies. If stellar interference is not correctly accounted for, it can lead to inaccurate conclusions about these fundamental aspects of the universe.

How can scientists minimize the impact of stellar interference in redshift measurements?

Scientists can minimize the impact of stellar interference by using advanced techniques and algorithms to correct for it. They can also carefully select the observation targets and avoid regions of the sky with a high concentration of stars. Additionally, using multiple data sets and cross-checking the results can help to identify and reduce the effects of stellar interference.

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