It is engraved into our common sense that for any two things two interact, they must exchange something, and according to Einstein the speed of the exchange cannot be instantaneous, but limited by the speed of light. For example, we believe that a charge feels the existence of another charge because of exchange of photons which travel at the speed of light. We believe nucleons feel other nucleons by exchange of mesons which are much heavier than photons and thus travel at a speed less than that of photons. Also, the exchange is very short ranged unlike in case of electromagnetic and gravitational interactions.
It is not yet established if gravitational interaction is due to the exchange of gravitons or something else but it is believed that the interactions are not instantaneous as Newton thought. Newton’s third law of equal and instantaneous opposite reaction to an action at a distance was ruled out by Einstein’s relativity, but now it seems to somehow come back in the form of non-local correlations of quantum events. If it could be extended to classical events then it could promote Mach’s conjecture which says that local physical laws are directly affected by the large-scale structure of the Universe. Non-local correlations also make teleportation possible without the speed limit as it forces us to give up the idea that something has to be exchanged in real space-time in order to transmit information.
It is not yet established if gravitational interaction is due to the exchange of gravitons or something else but it is believed that the interactions are not instantaneous as Newton thought. Newton’s third law of equal and instantaneous opposite reaction to an action at a distance was ruled out by Einstein’s relativity, but now it seems to somehow come back in the form of non-local correlations of quantum events. If it could be extended to classical events then it could promote Mach’s conjecture which says that local physical laws are directly affected by the large-scale structure of the Universe. Non-local correlations also make teleportation possible without the speed limit as it forces us to give up the idea that something has to be exchanged in real space-time in order to transmit information.