On Sat, Feb 23, 2019 at 3:08 PM <[email protected]> wrote: > On Friday, February 22, 2019 at 8:13:21 PM UTC-7, Brent wrote: >> >> On 2/22/2019 6:04 PM, [email protected] wrote: >> >> On Friday, February 22, 2019 at 4:55:41 PM UTC-7, Brent wrote: >>> >>> >>> >>> On 2/22/2019 2:40 PM, [email protected] wrote: >>> >>> Gravitons, as quanta of the metric field, are already relativistic >>>> particles and covariant. >>>> >>> >>> *I thought it's the equations of motion for the particular force, not >>> the mediating particles, that must be covariant. On a related topic for >>> this thread, where does GR depart from Mach's principle? That is, what did >>> Einstein implicitly (or explicitly) deny about Mach's principle? TIA, AG * >>> >>> >>> Einstein thought he would develop a theory that satisfied Mach's >>> principle, but as it turned out GR doesn't. For example the metric of >>> spacetime is a dynamic field and transmit momentum and energy, as shown by >>> LIGO. Mach's idea of spacetime as purely a relation between material >>> events couldn't do that. >>> >>> Brent >>> >> >> *Were you inferring covariance simply because the mediating particle for >> gravity, the graviton, travels at the SoL? * >> >> >> GR is a covariant theory. So it's quanta, gravitons, are covariant. >> > > *I could be mistaken, but I see gravitons as being part of a distinct > theory of gravity, which might give the same results as GR. In GR, the > paths are determined by geometry in the absence of forces, not by mediating > particles. AG * >
GR, as a theory, implies the existence of gravity waves. Wave, when quantised, give particles: these are the gravitons of the theory. Exchange of such gravitons does not necessarily have anything to do with the forces in the theory, or the formation of geodesics. Bruce -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
