Recent content by Chhhiral

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    Graduate Why a vector field can not be used to describe gravity?

    @robphy Very interesting, thanks!
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    Graduate Why a vector field can not be used to describe gravity?

    Thank you very much, I'll read it immediately
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    Graduate Why a vector field can not be used to describe gravity?

    In many books of general relativity I have found the following statement: a vector field produces repulsive forces between like charges so can not be used to describe gravity. But they do not show it. How can i show it or where can I find a book or a paper in which it is shown? Please, to avoid...
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    You have been so quick to downgrade my question ... but now you do not answer ... maybe do you want other references? Please answer me, is a very important question for me... thanks
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    Hobson, Michael Paul, George P. Efstathiou, and Anthony N. Lasenby.General relativity: an introduction for physicists. Cambridge University Press, 2006. pag:191 "A gravitational theory based on a vector field can be eliminated since such a theory predicts that two massive particles would repel...
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    I'm trying to understand why a vector field can not be used to describe gravity. Not because the force of Coulumb is so defined or because the Lagrangian of the electromagnetic field leads to Bhabha scattering...
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    Gasperini, Maurizio. Relatività Generale e Teoria della Gravitazione. Springer Milan, 2015. pag:27 the English version should be: Gasperini, Maurizio. Theory of Gravitational interactions. Springer Science & Business Media, 2013. at the chapter: "Towards a relativistic theory of gravitation". I...
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    in many books of general relativity I found the statement: a vector field produces repulsive forces between like charges so can not be used to describe gravity ...
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    Thanks, but your answer is equivalent to: take like charges and calculate the Coulomb force. My question is more general
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    Undergrad Vector field:one aspect that everyone knows but nobody shown

    Why a generic vector field produces repulsive forces between charges of the same sign? And where can I find a book or a paper in which it is shown?
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    Graduate Why the Shapiro delay is calculated with respect to the....?

    Sorry: I find that the error is exactly two times the difference between the value of the coordinates diference and the value of the physical distance.
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    Graduate Why the Shapiro delay is calculated with respect to the....?

    Maybe my question is not clear, but my English does not allow me to rephrase it in a clearer way. But I can do another question that can help me to another way: If you try to measure the position of Venus without the help of general relativity, only being on Earth, how wrong? I find that the...
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    Graduate Why the Shapiro delay is calculated with respect to the....?

    You are right but What you say is: RoundTripProperTime=(1-G*M/xA)*RoundTripCoordinateTime, as you said this is trivial. your answer about the difference between proper time and coordinate time difference. My question is about Shapiro time delay and geometrical meaning of isotropic coordinates.
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    Graduate Why the Shapiro delay is calculated with respect to the....?

    It is not my question... As you said this is a trivial effect. Thanks for answered me, however.
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    Graduate Why the Shapiro delay is calculated with respect to the....?

    Sorry again, I wrote: "...his value is (1+gamma)/2 times the value predicted using only the equivalence principle." I wanted write: "...his value is (1+gamma) times the value predicted using only the equivalence principle."