Difference between relativistic doppler effect and classical one?

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SUMMARY

The discussion centers on the differences between the relativistic Doppler effect and the classical Doppler effect, specifically in the context of sound and light. It is established that while classical Doppler effects can be explained through Galilean Relativity (GR) using velocity addition, the relativistic Doppler effect (ER) cannot be simplified in the same manner due to the constancy of the speed of light (c). The conversation highlights the existence of the transverse Doppler effect, which is unique to light and not accounted for in classical physics, thereby confirming that the two phenomena are fundamentally different.

PREREQUISITES
  • Understanding of Galilean Relativity (GR)
  • Familiarity with Einstein's Theory of Relativity (ER)
  • Knowledge of the Doppler effect in both sound and light
  • Basic grasp of the concept of transverse Doppler effect
NEXT STEPS
  • Research the mathematical formulation of the relativistic Doppler effect
  • Explore the implications of transverse Doppler effect in experimental physics
  • Study the differences between classical and relativistic physics in detail
  • Investigate real-world applications of the Doppler effect in astrophysics
USEFUL FOR

Physicists, students of physics, and anyone interested in the fundamental differences between classical and relativistic phenomena, particularly in the context of wave behavior in sound and light.

lightconstant
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When I ask for differences I am not meaning mathematical ones since that it is obvious:
We have a phenomenon p, p can be described by Galilean Relativity (GR)
and by Einstein Relativity (ER).
ER(p)!=GR(p)
The math expression that describes this phenomenon is different.
Then the doppler effect will have another mathematical expression
ER(dp)!=GR(p)
Maybe someone wants to say that GR is like a subset of ER for small velocities in reality It is not It looks similar but It is not, well let us get to the point.
Sound can be described by the classical doppler effect GR(d_e) by addition and substration of velocities though we know the velocity is constant due to the medium.
My question can we do the same with light? can we explain it mathematically with the addition of c+v, c-v?
I hope I have expressed myself clearly, I know c is a constant and We can not add velocities, what am I asking is if by using galilean relativity the doppler effect of light can be explained adding velocities, after all sound has a constant velocity and we add it.
Let us put it another way, is there any physical not mathematical proof, evidence, observation, meaning... that the doppler effect of light is different than the sound one?
Or Is It just the way It is expressed mathematically.
Because I see this applet:
http://webphysics.davidson.edu/applets/applets.html
and the phenomenon looks the same.
 
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lightconstant said:
When I ask for differences I am not meaning mathematical ones since that it is obvious:
We have a phenomenon p, p can be described by Galilean Relativity (GR)
and by Einstein Relativity (ER).
ER(p)!=GR(p)
The math expression that describes this phenomenon is different.
Then the doppler effect will have another mathematical expression
ER(dp)!=GR(p)
Maybe someone wants to say that GR is like a subset of ER for small velocities in reality It is not It looks similar but It is not, well let us get to the point.
Sound can be described by the classical doppler effect GR(d_e) by addition and substration of velocities though we know the velocity is constant due to the medium.
My question can we do the same with light? can we explain it mathematically with the addition of c+v, c-v?
I hope I have expressed myself clearly, I know c is a constant and We can not add velocities, what am I asking is if by using galilean relativity the doppler effect of light can be explained adding velocities, after all sound has a constant velocity and we add it.
Let us put it another way, is there any physical not mathematical proof, evidence, observation, meaning... that the doppler effect of light is different than the sound one?
Or Is It just the way It is expressed mathematically.
Because I see this applet:
http://webphysics.davidson.edu/applets/applets.html
and the phenomenon looks the same.

Much of what you say is not comprehensible. Classic doppler has no provision for transverse doppler (change in frequency of light emitted by a moving source exactly perpendicular to the receiver). This has been observed with light.

See: http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#Tests_of_time_dilation
 
Thank you PAllen I saw that somewhere but did not know it was only light related,
I guess the phenomenon It is not the same since one has transverse doppler and the other one does not.
Let me look at it and see what is about.
 

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