Undergrad Gravitational Redshift: Derivation from Static Metric

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The discussion focuses on deriving gravitational redshift from a static metric without relying on the equivalence principle or heuristic Newtonian methods. Participants suggest solving for null geodesics at different times and determining the proper time along worldlines of constant radii for emission and reception. Another proposed method involves calculating the energy of a null geodesic at infinity and relating it to the energy measured by static observers at different radii. The relationship between changes in proper time and frequency, as measured by redshift, is also examined, questioning whether a quantum perspective is being applied to a classical theory. The key takeaway is that the time dilation factor can be derived from the proper time between emission and arrival of light peaks.
redtree
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I am trying to find a derivation of gravitational redshift from a static metric that does not depend on the equivalence principle and is not a heuristic Newtonian derivation. Any suggestions?
 
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Solve for a null geodesic. Start one at ##(r,t_1)## and the other at ##(r,t_1+\Delta t)##. Determine the time between the events where the two geodesics cross some radius ##R##?
 
Ibix said:
Determine the time

More precisely, the proper time along a worldline of constant radius ##R## (the radius of reception), as compared with the proper time along a worldline of constant radius ##r## (the radius of emission).

Another method would be to compute the energy at infinity of a null geodesic, and then show how that relates to its energy as measured by static observers at ##r## and ##R##.
 
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Given that time and frequency are Fourier conjugates, how can changes in proper time relate directly to changes in frequency (as measured by redshift)? Or am I imposing a quantum perspective on a non-quantum theory?
 
redtree said:
Given that time and frequency are Fourier conjugates, how can changes in proper time relate directly to changes in frequency (as measured by redshift)? Or am I imposing a quantum perspective on a non-quantum theory?
You are.

To get the time dilation, all you need is the proper time between emission of successive peaks at the source and the proper time between the arrival of these peaks at the destination. The ratio between the two is the time dilation factor. You could do this calculation with two flashes of light emitted an hour apart at the source if you wanted.
 
In an inertial frame of reference (IFR), there are two fixed points, A and B, which share an entangled state $$ \frac{1}{\sqrt{2}}(|0>_A|1>_B+|1>_A|0>_B) $$ At point A, a measurement is made. The state then collapses to $$ |a>_A|b>_B, \{a,b\}=\{0,1\} $$ We assume that A has the state ##|a>_A## and B has ##|b>_B## simultaneously, i.e., when their synchronized clocks both read time T However, in other inertial frames, due to the relativity of simultaneity, the moment when B has ##|b>_B##...

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