On Wednesday, October 1, 2025 at 10:48:48 PM UTC-6 Brent Meeker wrote:
On 10/1/2025 7:13 PM, Alan Grayson wrote: On Wednesday, October 1, 2025 at 6:11:55 PM UTC-6 Brent Meeker wrote: On 10/1/2025 6:38 AM, Alan Grayson wrote: On Wednesday, October 1, 2025 at 7:20:13 AM UTC-6 John Clark wrote: On Wed, Oct 1, 2025 at 8:29 AM Alan Grayson <[email protected]> wrote: *> Have physicists in the last 120 years claimed that two paths of different lengths in spacetime which start and end at same events, have the same accelerations, except Brent in his diagram? AG* *In a word, yes. Two worldlines between the same events in spacetime can have different lengths even if both involve acceleration. And proper time is the length of your world line. But of course if they have identical acceleration histories then they are in the same worldline, not a different one.* You're writing nonsense. Brent has two worldlines with different lengths, claiming they have identical accelerations. AG And he included diagrams showing the accelerations had the same amplitudes and durations. And that even was redundant. From the diagram it is clear that Red and Blue had the same velocity at the initiation of their accelerations and they turned their velocity thru the same angle in each period of acceleration...hence one can infer mathematically that their (acceleration*duration) products were the same. Brent *That was your intention, but since the clock moving along the longer path, needs a greater turn if done in one acceleration, I don't think splitting the accelerations into two components solves your intention to make the accelerations of both paths equal. * What the hell does "solves you intention" mean. The velocities are the same and the angle thru which they turn is the same...those are hypotheticals of the story. It follows that the (acceleration*duration) are the same. *"Solves your intention" means your model establishes, from your pov, that acceleration does not solve the TP problem. This is plain English. Why can't you understand it? AG* *On the longer path, the further out it goes, the greater is the turn required, and hence, more acceleration. Drawing it in a way that makes the accelerations identical is impermissible if you're trying to prove the accelerations are identical. AG* *Recall that in the usual interpretation of the TP, where one twin is stationary and the other traveling, this situation is a limiting case of what you're doing in the diagram. * NO, IT IS THE SAME CASE. In my diagram it is clear that Blue is stationary for the duration of Red's trip. Are you going to claim that it matters whether Blue was stationary some other time?? *I never claimed it's the same case. You have two paths. One twin is stationary in the standard TP. In the case we're discussing, both are moving. I just brought up the case of the standard TP to discuss one limiting case. Then I discussed the other limiting case where both are moving and the paths juxtaposed. Didn't you understand what I was doing? AG* *It tends to confirm that the accelerations are not identical in your more general case. The only real proof of your claim is mathematically. The fact that your diagram affirms your claim is, IMO, insufficient. AG* Which only shows how ignorant or unserious you are. *No. What it shows is you're emotionally unqualified to consider yourself a teacher. Obviously, you don't have a clue what I am alleging. AG * Brent -- 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 view this discussion visit https://groups.google.com/d/msgid/everything-list/f7f306fb-34c5-4042-a649-a4094db9364dn%40googlegroups.com.
