Relation between

[apurvmj]

As speed of light is same always,will some one pls explain special relativity & red shift of light (Doppler effect).

[timo]

For "please explain scientific topic X", Wikipedia is usually a good first place to turn to. Or Google. Or, if you are serious about your question, a textbook.

Edited August 23, 2012 by timo

[Purephysics]

the speed of light © is indeed a physical constant (given the correct parametres). the doppler effect is to do with the frequency of light, not its speed (wave-partucle duality) in relation to the observer.

 

SR is not sonething i feel can be conpressed into a post. probably wiki that one. ;-)

[swansont]

the speed of light © is indeed a physical constant (given the correct parametres). the doppler effect is to do with the frequency of light, not its speed (wave-partucle duality) in relation to the observer.

Wave/particle issues are related to quantum mechanics, not relativity.

[Purephysics]

Wave/particle issues are related to quantum mechanics, not relativity.

You're absolutely right, I meant in the way that light acts as both particle and wave. I beleive I'm right in saying that with respect to red shift and the doppler effect, we are viewing light as a wave not a particle.

[swansont]

You're absolutely right, I meant in the way that light acts as both particle and wave. I beleive I'm right in saying that with respect to red shift and the doppler effect, we are viewing light as a wave not a particle.

Photons get redshifted, too. The Doppler effect happens with individual atoms undergoing transitions.

[apurvmj]

As per wikipedia

In physics (especially astrophysics), redshift happens when light seen coming from an object that is moving away is proportionally increased in wavelength, or shifted to the red end of the spectrum.

As per #Purephysics its effect of frequancy.

 

If wavelenght of light wave increaces to maintain the speed its frequancy should decrease.

But if frequacy changes so does the properties of EM waves. can we say red light will become infra red when we move away from red light source? correct me wherever I'm wrong.

When will time dialation come in to play? Does it have any effect on frequancy as its time function.

 

For me understanding Doppler effect with sound frequancies is easy, as they are pressure waves, but its difficult with "super natural kind " light waves.

Hope you all understand my position.

[swansont]

As per wikipedia

In physics (especially astrophysics), redshift happens when light seen coming from an object that is moving away is proportionally increased in wavelength, or shifted to the red end of the spectrum.

As per #Purephysics its effect of frequancy.

 

If wavelenght of light wave increaces to maintain the speed its frequancy should decrease.

But if frequacy changes so does the properties of EM waves. can we say red light will become infra red when we move away from red light source? correct me wherever I'm wrong.

When will time dialation come in to play? Does it have any effect on frequancy as its time function.

 

For me understanding Doppler effect with sound frequancies is easy, as they are pressure waves, but its difficult with "super natural kind " light waves.

Hope you all understand my position.

Yes, a photon that is high energy in its own frame can be shifted to a low energy one in another, so a visible photon emitted could be IR when detected. You can see this on a smaller scale if you shine laser light on an atom with a narrow resonance. The light will only be absorbed if the atom is moving at the right speed (or small range of speeds), so that the Doppler shift puts it into resonance with the atom. Atoms outside that band do not absorb the light.

 

Time dilation comes into play with the gravitational redshift of GR.

[EMField]

Because light is not constant contrary to what you have been told. light is only constant when and if it travels in a true vacuum, i.e. with no medium present, or in the space between atoms.

 

http://en.wikipedia.org/wiki/Dielectric

 

This is because all mediums, including the one that exists within our galaxy are NOT true vacuums. It is filled with electrified particles.

 

http://www.nasa.gov/mission_pages/rbsp/news/electric-atmosphere.html

 

And also contrary to what you have been told, red-shift is mainly due to plasma electron density, the only laboratory evidence that anything can affect the speed or wavelength of light.

 

http://www.sciencedirect.com/science/article/pii/S0030402608000089

 

And this is what electron density can do to the speed of light.

 

http://science.nasa.gov/science-news/science-at-nasa/2002/27mar_stoplight/

 

http://www.news.harvard.edu/gazette/2001/01.24/01-stoplight.html

[Phi for All]

And also contrary to what you have been told, red-shift is mainly due to plasma electron density, the only laboratory evidence that anything can affect the speed or wavelength of light.

!

Moderator Note

You've been warned multiple times about hijacking mainstream science threads with your pet theories. People come to the mainstream sections for mainstream, accepted answers, not woo.

 

Another week suspension, second strike, next time it will be permanent.