What's the role of stellar interference in redshifts?

  • Context: Graduate 
  • Thread starter Thread starter Neuvotonian
  • Start date Start date
  • Tags Tags
    Interference Stellar
Click For Summary

Discussion Overview

The discussion revolves around the role of stellar interference, particularly gravitational lensing, in the context of redshifts and their implications for observing supernovae and other astronomical phenomena. Participants explore concepts related to light wave interactions, spectrography, and the complexities of measuring redshifts in the presence of gravitational effects.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants question the role of interstellar combination of light waves in the observed redshifts, particularly in relation to the vast number of galaxies.
  • There is a request for clarification on what is meant by "interstellar combination of light waves."
  • One participant suggests that the discussion could focus on the effects of gravitational lensing on the apparent magnitudes of supernovae, linking it to redshifts.
  • Another participant mentions that spectrography can provide insights into various properties of astronomical objects, including momentum and composition.
  • There is a consideration of how different gravitational strengths might yield similar spectrographic results, raising questions about the relationship between distance to the source and wavelength changes in the red part of the spectrum.
  • A participant notes the complexity of separating frequency measurements to account for different redshift adjustments, referencing a collaborative article on redshift and the cosmic distance ladder.
  • One participant asserts that gravitational lensing does not affect the frequency of lensed photons, stating that gravitational blueshift occurs only for photons entering a gravitational well, which then redshift back upon exiting.

Areas of Agreement / Disagreement

Participants express differing views on the effects of gravitational lensing and the nature of redshifts, indicating that multiple competing perspectives remain unresolved.

Contextual Notes

Participants highlight the need for a nuanced understanding of the processes involved in measuring redshifts and the potential influence of gravitational effects, indicating that there are many steps and methodologies involved that may not yield straightforward answers.

Neuvotonian
Messages
5
Reaction score
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?
 
Space news on Phys.org
Enlighten me, what is interstellar combination of light waves?
 
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?
 
Sounds like your interested in the spectrography aspects. If so various details such as composition. Momentum etc can be derived from spectrometry
 
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?
 
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
 
Last edited:
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.
 

Similar threads

  • · Replies 39 ·
2
Replies
39
Views
8K
  • · Replies 30 ·
2
Replies
30
Views
7K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 23 ·
Replies
23
Views
4K
  • · Replies 34 ·
2
Replies
34
Views
5K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 15 ·
Replies
15
Views
3K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 15 ·
Replies
15
Views
4K