Path: csiph.com!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: whodat Newsgroups: sci.physics.relativity Subject: Re: Separation of Accelerating Observers in Special Relativity Date: Fri, 22 Dec 2023 15:53:31 -0600 Lines: 37 Message-ID: References: <24950084-2a92-7e26-1b19-0c00c9ad640c@comcast.net> <5882dd82-d22d-4d4c-9cd6-27d981f99ad0n@googlegroups.com> <7qudnXMNOMKeqx74nZ2dnZfqlJxj4p2d@giganews.com> <-v2cnYDq0JWmUB74nZ2dnZfqlJ9j4p2d@giganews.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Trace: individual.net ijdNRqW2w43w2UFRZulTwA6yAr00620iCzV/ZbujrJU+fJ/aA0 Cancel-Lock: sha1:UGy5WgR7YIcOLg+Vdnj8NjYTHoc= sha256:7sxizFYy+NbSVNZVf5HeDs7giiXBAfGZBAcSrVfs0GU= User-Agent: Mozilla Thunderbird Content-Language: en-US In-Reply-To: <-v2cnYDq0JWmUB74nZ2dnZfqlJ9j4p2d@giganews.com> Xref: csiph.com sci.physics.relativity:626337 On 12/20/2023 11:29 PM, Tom Roberts wrote: > On 12/20/23 1:06 PM, Mike Fontenot wrote: >> On 12/20/23 11:44 AM, Tom Roberts wrote: >>> Assuming the person on the trailing rocket measures the separation >>>  simultaneously in their successive instantaneously co-moving >>> inertial frames, that separation MUST successively increase. >> >> That's NOT the way person on the trailing rocket measures the >> separation!  He measures the separation with a tape measure, and >> THAT shows the separation is constant. > > WHAT tape measure? -- none is specified in the problem. > > Add one and you're still wrong: > To qualify as a tape measure, it must execute Born rigid motion, nailed > down only at the trailing rocket -- this makes it always be at rest in > the instantaneously co-moving inertial frame of the trailing rocket, so > this is no different from what I said above. Born rigid motion requires > the leading end of the tape measure to have a smaller proper > acceleration than the trailing rocket, with the difference evenly spread > out along its length. Note the two rockets do not execute Born rigid > motion, because they have equal proper accelerations; the leading rocket > has a larger proper acceleration than the leading end of the tape > measure, and thus pulls away from it. So the tape measure shows the > separation is increasing. This is no different from what I said above. > > I do not know why Fontenot keeps getting this wrong. Or why he keeps > ignoring me when I tell him this. Or why he ignores the voluminous > literature on this. He has been obsessing over this scenario for many > years, gets it wrong, and refuses to THINK about it -- see THINK 1 and > THINK 2 of my previous message for a very simple demonstration of my > claims. > > Tom Roberts Wasting your time. But then it is yours to waste.