Gravitational red shift question

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SUMMARY

The discussion centers on the phenomenon of gravitational redshift, specifically how the frequency of a photon decreases as it moves away from a star. The equation presented, hf' = hf(1 - GM/(Rc^2)), illustrates that as the distance R increases, the frequency f' diminishes. This occurs because the photon must escape the gravitational field of the star, resulting in a decrease in kinetic energy as potential energy increases. The participants express confusion regarding the mathematical representation, but the underlying physics is clearly established.

PREREQUISITES
  • Understanding of gravitational fields and potential energy
  • Familiarity with the concept of photon energy and frequency
  • Basic knowledge of general relativity principles
  • Mathematical proficiency in manipulating equations involving constants like G, M, R, and c
NEXT STEPS
  • Research the implications of gravitational redshift in astrophysics
  • Study the derivation and applications of the Schwarzschild metric
  • Explore the relationship between energy conservation and gravitational potential
  • Learn about experimental evidence supporting gravitational redshift, such as observations from white dwarf stars
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Astronomy students, physicists, and anyone interested in the effects of gravity on light and energy in astrophysical contexts.

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Why does the frequency of a photon emitted from the surface of a star decrease as it moves away from the star?
if hf`=hf(1-GM/(R*c^2)
then as the distance becomes larger, R becomes larger, so f`becomes smaller?
 
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We use the fact that the total energy must remain constant.
I'm not 100% sure, but I think t hat when leaving the star, the photon has to get out of the gravitation-field of the star, therefore its kinetic energy has to decrease since the potential energy is rising.
 
hmm... that makes sense, but the mathematical equation looks weird...
it seems to say otherwise~
 
still a little weird~
 

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