On Friday, February 22, 2019 at 9:12:02 PM UTC-7, Bruce wrote: > > On Sat, Feb 23, 2019 at 3:08 PM <[email protected] <javascript:>> 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 >
*Very clarifying. Then, since gravitational waves have been detected, it must be that gravitons exist, but too low in energy to be detected. AG * -- 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.
