On Sat, Dec 29, 2018 at 6:37 PM Brent Meeker <[email protected]> wrote:
>>> *It's an example of a geodesic being the longest path (in interval) >>> between two events in 4-space.* >> >> > >> I think you meant shortest path, there is no unique longest path it can >> be made as long as you like. > > > *> No, I mean longest path. * > I just typed "define:geodesic" into Google and this is what I got: *adjective* 1. 1. Relating to or denoting the shortest possible line between two points on a sphere or other curved surface. 2. 2. Another term for geodetic. > *> The stay-home twin experiences the longest duration between departure > and arrival of the traveling twin. * > Yes. Relativity says everything moves in a geodetic unless a force it acting on them, and if the traveling twin was moving close to the speed of light but eventually returned to where he started then a force must have acted on him. > > The traveling twin measures a shorter interval because he takes a > non-geodesic path. > I agree, a force acted on the traveling twin so he took a non-geodesic path and experienced a shorter proper time between events than his brother who was on a geodesic. But in Feynman's example no force was acting on either clock , both were in a inertial frame or close to one assuming the clocks were small compared to the distance from the center of the Earth. John K Clark -- 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.
