On 1/2/2014 8:00 PM, LizR wrote:

On 3 January 2014 15:52, Jason Resch <jasonre...@gmail.com<mailto:jasonre...@gmail.com>> wrote:## Advertising

On Thu, Jan 2, 2014 at 9:31 PM, LizR <lizj...@gmail.com <mailto:lizj...@gmail.com>> 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,...`

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