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Author Topic: Could transverse velocities explain anomalous ultra red shifted galaxies?  (Read 2476 times)

Offline CPT ArkAngel

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Could transverse relativistic velocities explain anomalous ultra red shifted galaxies?

The relativistic transverse doppler effect produces a red shift. Thus any relativistic transverse component of velocity will produce a higher red shift!

What do you think?





 

Offline Atomic-S

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Interesting idea. But I don't know the answer.
 

Offline imatfaal

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My idea of the transverse doppler effect is that it concerns two objects on opposite trajectories and at the moment of closest approach any light detected at that moment will be blueshifted and any light emitted at that moment will be red-shifted.  it is the moment of switch over from both parties seeing the other blueshifted as they approach and both parties seeing the other red shifted as they depart. 

I am not sure how this would apply for distant galaxies that are heading away faster and faster. 

If you have a link to a  different usage of transverse doppler effect I would love to see it
 

Offline CPT ArkAngel

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The relativistic doppler effect can be subdivided in 2 parts. The newtonian part and the pure relativistic part due to time dilation or length contraction.

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

Longitudinal velocity component:

The effect on the frequency in the velocity direction for the newtonian part is greater than 1 for an approaching speed (1+v/c) and smaller than 1 for a receding speed (1-v/c). For the purely relativistic doppler frequency shift, it is equal to the gamma function and it is thus always greater than 1, or blue shifted.

Transverse velocity component:

For a transverse velocity, there is no newtonian shift, but the relativistic part is now 1/gamma, always a redshift. This cannot be a discountinuous function so any transverse component will introduce an additional redshift!!!

If the excessive redshift was due to dust, it would be visible by scattering effect (blurring effect).

« Last Edit: 29/08/2012 02:36:22 by CPT ArkAngel »
 

Offline imatfaal

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CPT from your page
Quote
Transverse Doppler effect

The transverse Doppler effect is the nominal redshift or blueshift predicted by special relativity that occurs when the emitter and receiver are at the point of closest approach. Light emitted at this instant will be redshifted. Light received at this instant will be blueshifted.

I don't know that you mean - cos the definition from wikipedia doesn't fit your idea
 

Offline CPT ArkAngel

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Look at the graphical java applet. I differentiate the newtonian and relativistic part of the doppler effect which they don't.

The problem with the hyper redshifted galaxies, is that they are nearer than their red shifts indicate. There is 3 possible causes, not 2. A difference of gravity potential between here and these galaxies; dust; and/or a relativistic transverse component of velocity.

 

Offline imatfaal

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Read the section marked Transverse Doppler Effect

Quote
The transverse Doppler effect is the nominal redshift or blueshift predicted by special relativity that occurs when the emitter and receiver are at the point of closest approach. Light emitted at this instant will be redshifted. Light received at this instant will be blueshifted.
There is no Newtonian component to transverse doppler because in pre-Einstein we had absolute time.  The Transverse Doppler Effect is an instantaneous effect - it does not maintain over time; before and after the moment of closest approach you have normal relativistic doppler
 

Offline CPT ArkAngel

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It is a misconception Mat. When the light is observed from the closest point of the path, it is redshifted due to time dilation alone (1/gamma). Why the relativistic longitudinal component is gamma and the transverse component is 1/gamma? Length contraction vs time dilation... At 45 degree angle the relative time dilation is equal and opposite to the effect of length contraction and we are left with the classical doppler shift. It is not a discontinuous function. This is an extremely important experiment to perform. The frequency must be measured for all angles, not the time dilation: relative time dilation should be constant. It will give us a deep insight on wave-particle duality and a basic conceptual model relating the gravitational redshift to the transverse redshift... If you search for informations on the transverse doppler effect, you will find more controversies than experimental facts, unfortunately.
« Last Edit: 29/08/2012 02:54:01 by CPT ArkAngel »
 

Offline imatfaal

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Hmmm.  Gonna need to think about this one.  My knowledge and scant reading does not bear out your claims - but it is far from simple.  Do you have any links for the "controversy"?   

The Doppler effect from a body on a path of arbitrary angle is not simple - but it is not terribly complicated.  This is not the transverse doppler effect - although at some point it might resolve to it. 
 

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