I read once that string theory explains gravitation via invoking quanta of the electromagnetic field to transmit the force of gravity over large distances. Is this the truth? I read somewhere else that string theory invokes gravitons and extra dimensions to explain the force of gravity. Since my understanding of string theory isn't excellent, and since it could be an informative exercise, I was wondering if anyone would mind explaining to me exactly how string theory yields gravity in either the Newtonian or relativistic senses.

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    $\begingroup$ I'm sorry, I know nothing about string theory. I'll wait for someone else to accept the challenge $\endgroup$
    – Prallax
    Aug 28 at 20:25
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    $\begingroup$ see this post and links therein physics.stackexchange.com/questions/30005/… $\endgroup$
    – Kosm
    Aug 28 at 20:29
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    $\begingroup$ @SamCottle It has nothing to do with electromagnetism. Perturbative string theory automatically has massless spin-2 particles, and any reasonable theory with interacting massless spin-2 particles has gravity. For a nonperturbative perspective, the AdS/CFT correspondence is the most-studied framework so far. (That's not an answer, just a couple of sentences with keywords to point you in the right direction, because I don't think a one-post answer is feasible.) $\endgroup$ Aug 28 at 20:57
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    $\begingroup$ What you might've read is that string theorists make use of dimensional reduction which was originally formalized as part of a different theory by Kaluza and Klein which attempted to unify gravitational and electromagnetic fields back when people thought these were the only two forces. $\endgroup$ Aug 28 at 20:59
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    $\begingroup$ @ChiralAnomaly even more basic the (assumed) vanishing of the beta functions imply Einstein Field equation (for vacuum) $\endgroup$
    – lalala
    Aug 28 at 21:36