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Re: Light Falls in Gravity: Its Speed Increases or Decreases?

Message-ID <5BD49005.7873@ix.netcom.com> (permalink)
Date 2018-10-27 09:19 -0700
From The Starmaker <starmaker@ix.netcom.com>
Newsgroups sci.physics.relativity
Subject Re: Light Falls in Gravity: Its Speed Increases or Decreases?
References <df4d9f14-3286-4e0c-960b-c5ce3c0349a3@googlegroups.com>

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Pentcho Valev wrote:
> 
> Einstein's general relativity is absurd - it predicts that the speed of light falling in a gravitational field DECREASES:
> 
> "Contrary to intuition, the speed of light (properly defined) decreases as the black hole is approached. [...] If the photon, the 'particle' of light, is thought of as behaving like a massive object, it would indeed be accelerated to higher speeds as it falls toward a black hole. However, the photon has no mass and so behaves in a manner that is not intuitively obvious."
>  http://www.physlink.com/Education/AskExperts/ae13.cfm
> 
> "...you will find in section 3 of that paper Einstein's derivation of the variable speed of light in a gravitational potential, eqn (3). The result is: c'=c0(1+φ/c^2) where φ is the gravitational potential relative to the point where the speed of light c0 is measured. Simply put: Light appears to travel slower in stronger gravitational fields (near bigger mass). [...] You can find a more sophisticated derivation later by Einstein (1955) from the full theory of general relativity in the weak fi
> 
> "Thus, as φ becomes increasingly negative (i.e., as the magnitude of the potential increases), the radial "speed of light" c_r defined in terms of the Schwarzschild parameters t and r is reduced to less than the nominal value of c."
> 
> Actually the speed of falling light INCREASES (near Earth's surface the acceleration is g), as per Newton's theory:
> 
> 
> 
> 
>  http://web.pdx.edu/~pmoeck/books/Tipler_Llewellyn.pdf
> 
> Pentcho Valev



is gravity a distance force?

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Thread

Light Falls in Gravity: Its Speed Increases or Decreases? Pentcho Valev <pvalev@yahoo.com> - 2018-10-27 00:45 -0700
  Re: Light Falls in Gravity: Its Speed Increases or Decreases? The Starmaker <starmaker@ix.netcom.com> - 2018-10-27 09:19 -0700
  Re: Light Falls in Gravity: Its Speed Increases or Decreases? Pentcho Valev <pvalev@yahoo.com> - 2018-10-28 02:32 -0700

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