Path: csiph.com!weretis.net!feeder6.news.weretis.net!news.glorb.com!peer03.iad!feed-me.highwinds-media.com!news.highwinds-media.com!border1.nntp.dca1.giganews.com!nntp.giganews.com!buffer1.nntp.dca1.giganews.com!nntp.earthlink.com!news.earthlink.com.POSTED!not-for-mail NNTP-Posting-Date: Mon, 24 Jul 2017 02:19:19 -0500 Message-ID: <59759F7C.C14@ix.netcom.com> Date: Mon, 24 Jul 2017 00:19:24 -0700 From: The Starmaker Reply-To: starmaker@ix.netcom.com X-Mailer: Mozilla 3.04Gold (WinNT; U) MIME-Version: 1.0 Newsgroups: sci.physics.relativity Subject: Re: The correct explanation for the twin paradox References: <086f7a5d-bd46-44dc-abf3-98488917a499@googlegroups.com> <7ecda924-3461-419e-84c9-7b4800de7bf7@googlegroups.com> <2764577b-f7d5-441a-97ca-4b070507f5b8@googlegroups.com> <57790307-91c3-4956-a8e3-ed07c8b92573@googlegroups.com> <7e69dc9d-5173-43bf-9167-7dcacacbc713@googlegroups.com> <0d4ffa90-a36f-4ea0-86d3-eb8956d94861@googlegroups.com> <0e54850b-ea98-4902-b7b2-85ef765772f2@googlegroups.com> <2057cab3-d71d-4bcc-8728-5cac413e935d@googlegroups.com> <13af5343-27eb-4565-877d-94ea6ba19f6c@googlegroups.com> <5974E333.20CF@ix.netcom.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Antivirus: Avast (VPS 170723-2, 07/23/2017), Outbound message X-Antivirus-Status: Clean Lines: 82 X-Usenet-Provider: http://www.giganews.com NNTP-Posting-Host: 108.219.229.47 X-Trace: sv3-coE27NhH4X2EhEU/Nl9zZGTkiEms8r0Txb946GDbbcjOSDsBnUGzC+Ie9MjdF8t4TTYGTCgQa3ogHnd!7aKZp2q9HjMGX9dN1n5Rf5F3Mb4lSLs7HOZLJ1SHpE7pN/GGuQGVqWI7oLZ5Y7rqUthuaLa0MkUw!3zFlh0CG5w== X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 6035 X-Received-Bytes: 6126 X-Received-Body-CRC: 1637468376 Xref: csiph.com sci.physics.relativity:425954 The Starmaker wrote: > > Nicolaas Vroom wrote: > > > > On Friday, 21 July 2017 16:29:29 UTC+2, tjrob137 wrote: > > > On 7/20/17 7/20/17 2:50 PM, Nicolaas Vroom wrote: > > > > My understanding is that an odometer is used to measure distance. > > > > [...]What is your point? > > > > > > The point is that odometers measure distance, while clocks measure > > > elapsed (proper) time. This is an ANALOGY. > > okay. IMO you have to be carefull to use such an ANALOGY. > > > > On Thursday, 20 July 2017 17:08:45 UTC+2, Paparios wrote: > > > Let again try the car odometer analogy. Two identical cars make a trip > > > from Chicago to New York, but they use different routes. > > Consider the following 2 options: > > One car travels straight from Chicago to New York. The odometer will > > show 600 miles. > > Car two travels from Chicago to Houston and then straight to New York. > > The odo meter will show 600 + 600 = 1200 miles. > > Both car will start at the same moment and arrive at the same moment. > > This implies that the second car drives the fastest. > > Both cars have a clock. Both clocks are reset at the start of the experiment. > > Question: when both cars are in New York will both clocks show the > > same reading? > > > > > The usual twin paradox with > > > instantaneous accelerations is a triangle, and the clocks measure > > > the elapsed (proper) time along each path. As the geometry is > > > hyperbolic, the one that traversed two sides of the triangle > > > experienced less elapsed (proper) time than the one who traversed one. > > > > This implies (if my understanding is correct) that the second clock should > > show less elapsed proper time. > > In simple terminology; the second clocks runs behind > > > > > Each odometer measured 1 meter for every meter traversed. > > Okay > > > Each clock measured 1 second for every second traversed. > > Here we have a problem. What do you mean? > > > > To solve the issue "how clocks perform" we have to made two (4) assumptions: > > 1) We agree that every where, the universe, at this moment > > has the same time after the Big Bang. This implies that the Universe > > has everywhere the same age. > > 2) We agree that every where in the universe at this moment, > > all events that can be be indentified, are simultaneous events. > > 3) As such we also agree that a self centered view of the Universe > > (of what I see and observe) is irrelevent. > > 4) As such it is our responsible to define a clock which shows > > the age of the Universe. > > > > The problem is that an odometer is not very helpfull in this > > exercise, which as far as I understand can only be used to measure > > distances here on earth (?) and not in space. > > > > When you want to study the twin "paradox" different identical clocks > > with different speeds are used. Different speeds require accelerations > > and these accelerations change the performs of the clocks. > > At the pages 26 and 27 in the book GRAVITATION the concept "good" and > > "bad" clocks is introduced. "Bad" clocks undergo accelarations. > > Accelerations imply different speeds. IMO when you change the speed > > it is the inner workings of the clock that changes. This is important > > for a clock which uses lightsignals to function, because the speed > > of light does not change. The result is that the usual clock rate > > changes. The most important lesson is "not" to use clocks with > > different speeds when you want to unravel the laws of nature. > > > > A very interesting article to study is this: > > http://www.nature.com/news/witness-gravity-s-quantum-side-in-the-lab-1.22273 > > > > Nicolaas Vroom > > wat kind of clock was einstein using in his twin paradox thought experiment, a "good" clock or a "bad" clock? most likely a "bad" clock since einstein doesn't really want to measure the exact time... but if you combine a light-clock with a space-time odometer..