On Fri, Jan 3, 2014 at 10:19 AM, Edgar L. Owen <[email protected]> wrote:
> Jason, > > If the acceleration is the same, the slowing of clock time will be the > same... Doesn't matter where it is. Or equivalently (by the principle of > equivalence) it could be standing 'still' in a strong gravitational field. > > Edgar > > Okay but this is certainly not what happens. If you spent 4 minutes accelerating and came back, there would not be a 4 year age difference when Pam returned. Jason > > > > On Friday, January 3, 2014 10:06:08 AM UTC-5, Jason wrote: >> >> >> >> >> On Fri, Jan 3, 2014 at 9:21 AM, Edgar L. Owen <[email protected]> wrote: >> >>> Lliz, Brent and Jason, >>> >>> Actually Liz is correct here, by GR it is the acceleration. That is the >>> physical cause of the clock time differences of the twins. >>> >> >> In my experiment, lets say the acceleration lats for a total of 4 >> minutes: one minute to accelerate up to 0.8 c, one minute to slow down at >> Proxima Centauri, one minute to accelerate back up to 0.8 c toward Earth, >> and a final minute to accelerate down to back at Earth. >> >> If the accelerations alone account for the clock discrepancies, then >> there would be no need to go to Proxima Centauri at all. Pam could spend 4 >> minutes whizzing around the solar system and get in all the same >> accelerations. >> >> Is this what you are saying? >> >> Jason >> >> >>> It is true the effects can also be analyzed just by spacetime paths as >>> others have suggested, but it is actually the acceleration (or equivalent >>> gravitational field which is in effect an acceleration) which actually >>> physically produces the clock time differences when the twins meet up again. >>> >>> Edgar >>> >>> >>> On Friday, January 3, 2014 1:27:55 AM UTC-5, Liz R wrote: >>>> >>>> On 3 January 2014 17:30, meekerdb <[email protected]> wrote: >>>> >>>>> On 1/2/2014 8:00 PM, LizR wrote: >>>>> >>>>> On 3 January 2014 15:52, Jason Resch <[email protected]> wrote: >>>>> >>>>> On Thu, Jan 2, 2014 at 9:31 PM, LizR <[email protected]> wrote: >>>>>> >>>>>>> Jason, >>>>>>> >>>>>>> You may be missing the fact that the acceleration of the space >>>>>>> traveller is what causes the twin paradox. >>>>>>> >>>>>> >>>>>> I would say it is not so much the acceleration that explains the >>>>>> paradox, but the fact that no matter how you rotate the paths, you always >>>>>> see a kink in the path Pam takes. >>>>>> >>>>> >>>>> May I venture to suggest this is the same thing :-) >>>>> >>>>> >>>>> That's not exactly wrong - but it tends to make it confusing. It's >>>>> like saying a road from A to B is longer than as-the-crow-flies because of >>>>> its curves. Yeah, that's true; but if you want to calculate how much >>>>> longer you see that the rate of excess distance is proportional to the >>>>> first integral of the curvature and so the total excess is the second >>>>> integral of the curvature - which is just the distance. So it boils down >>>>> to unstraight lines are longer than straight lines. All the specific >>>>> details of acceleration get integrated out so it's easy to see that a >>>>> broken line (infinite accelerations) is just longer. Or in spacetime, >>>>> unstraight worldlines are shorter than straight ones. To phrase it in >>>>> terms of acceleration misleads people into thinking about the stressful >>>>> effects of acceleration and how that could affect a clock,... >>>>> >>>>> I bow to your superior knowledge. I wasn't thinking about the aging >>>> effects of acceleration (as in the Heinlein story where they have to fly to >>>> Pluto at 3G) but just the fact that the course changes are the only way the >>>> twin paradox can be enacted - that is to say, it's what breaks the symmetry >>>> that otherwise exists between one ref frame's measurements and another's. >>>> >>>> -- >>> 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 http://groups.google.com/group/everything-list. >>> For more options, visit https://groups.google.com/groups/opt_out. >>> >> >> -- > 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 http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/groups/opt_out. > -- 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 http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
