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The problem of simultaneity

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  The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-01 00:46 +0000
    Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-01 07:06 +0200
      Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-01 07:44 +0000
        Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-01 11:07 +0200
          Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-01 09:45 +0000
            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-01 13:02 +0200
              Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-01 11:31 +0000
                Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-01 13:37 +0200
      Re: The problem of simultaneity Dan Wawrzaszek <kr@wskenezr.pl> - 2025-10-01 13:10 +0000
      Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-01 13:39 +0000
        Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-01 16:32 +0200
          Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-01 09:47 -0700
            Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-02 09:52 +0200
              Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-04 20:39 +0200
                Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-05 11:00 +0200
                  Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-05 12:38 +0200
                    Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-05 12:43 +0200
                    Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-05 10:22 -0700
                      Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-05 14:01 -0700
                        Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-05 23:56 -0700
                        Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-06 21:13 -0700
                    Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-07 10:05 +0200
                      Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-07 10:51 +0200
                        Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-07 14:37 -0700
                          Re: The problem of simultaneity Tommy Bagirov <yggoo@iooma.ru> - 2025-10-07 21:48 +0000
                            Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-07 15:22 -0700
                              Re: The problem of simultaneity Shannon Bekovich-Cherkassky <sciaa@ssiivsoea.ru> - 2025-10-08 10:28 +0000
                            Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-08 00:08 +0000
                              Re: The problem of simultaneity Fidencio Bagdasarov <ia@ddo.ru> - 2025-10-08 10:31 +0000
                          Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-07 15:08 -0700
                        Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-09 09:32 +0200
                          Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-09 11:28 +0000
                            Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-11 09:11 +0200
                          Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-09 14:08 +0200
                            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-09 16:21 +0200
                              Re: The problem of simultaneity Derric Bezumov <eebmm@dbdv.ru> - 2025-10-10 15:10 +0000
                          Re: The problem of simultaneity Darryn Belorusov <rodryo@nldulan.ru> - 2025-10-09 12:46 +0000
                          Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-09 16:56 +0200
                          Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-09 11:46 -0700
                            Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-09 20:18 -0700
                            Re: The problem of simultaneity Huey Moshetov <uve@veeo.ru> - 2025-10-10 07:12 +0000
                              Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-10 10:44 -0700
                            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-10 10:51 +0200
                              Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-10 10:48 -0700
                            Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-11 09:18 +0200
                              Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-11 09:28 +0000
                                Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-13 07:59 +0200
                                  Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-13 21:59 +0200
                                    Re: The problem of simultaneity Williard Romeijnders <jimso@dilidi.nl> - 2025-10-13 20:36 +0000
                                    Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-13 13:45 -0700
                                    Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-14 07:53 +0200
                                    Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-15 09:44 +0200
                                      Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-15 10:58 +0200
                                        Re: The problem of simultaneity Dusty Wronski <yst@ok.pl> - 2025-10-15 10:26 +0000
                                        Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-16 06:22 +0200
                                      Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-15 20:05 +0200
                                        Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-15 20:49 +0200
                                          Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-15 19:15 +0000
                                            Re: The problem of simultaneity squalk <sq@net.inv> - 2025-10-15 20:44 +0100
                                              Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-15 13:19 -0700
                                            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-16 08:14 +0200
                                              Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-16 08:16 +0200
                                        Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-16 07:02 +0200
                                          Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-16 00:44 -0700
                                          Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-16 19:42 +0200
                                            Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-16 17:51 +0000
                                              Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-18 11:39 +0200
                                                Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-18 11:43 +0200
                                                  Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-18 12:16 +0200
                                                Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-18 12:11 +0200
                                                Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-18 13:37 +0000
                                                  Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-18 19:52 +0200
                                                  Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-19 21:02 +0200
                                                    Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-20 09:50 +0200
                                                Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-18 13:39 +0000
                                                  Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-18 13:40 +0000
                                                  Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-18 13:52 +0000
                                                Re: The problem of simultaneity Zackee Barazbiev <vbez@eaek.ru> - 2025-10-18 13:50 +0000
                                            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-16 21:11 +0200
                                  Re: The problem of simultaneity Mikko <mikko.levanto@iki.fi> - 2025-10-14 13:11 +0300
                                    Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-14 12:39 +0200
                                    Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-15 09:54 +0200
                                      Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-15 10:59 +0200
                                      Re: The problem of simultaneity Mikko <mikko.levanto@iki.fi> - 2025-10-15 12:32 +0300
                                        Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-16 06:39 +0200
                                          Re: The problem of simultaneity Mikko <mikko.levanto@iki.fi> - 2025-10-16 12:53 +0300
                                      Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-15 08:26 -0700
                                        Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-16 06:53 +0200
                                          Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-16 00:41 -0700
                                      Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-15 20:05 +0200
                                        Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-15 20:37 +0200
                                          Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-15 19:14 +0000
                                            Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-16 08:04 +0200
                                              Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-17 00:19 +0000
                                                Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-17 07:36 +0200
                                        Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-15 11:51 -0700
                                        Re: The problem of simultaneity Maykel Schneijder <eaa@eleeadmia.nl> - 2025-10-15 18:59 +0000
                              Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-11 21:43 +0200
                                Re: The problem of simultaneity Mikko <mikko.levanto@iki.fi> - 2025-10-12 13:03 +0300
                                  Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-12 12:33 +0200
                                  Re: The problem of simultaneity Dennett Poplawski <swpt@ltoea.pl> - 2025-10-12 10:53 +0000
                                Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-12 21:13 +0200
                                  Re: The problem of simultaneity Elier Szczepanski <eee@spi.pl> - 2025-10-12 19:50 +0000
                                Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-13 08:31 +0200
                                  Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-13 00:03 -0700
                                  Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-13 22:00 +0200
                                    Re: The problem of simultaneity The Starmaker <starmaker@ix.netcom.com> - 2025-10-13 13:54 -0700
      Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-02 09:20 +0200
        Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-04 21:00 +0200
          Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-05 11:16 +0200
            Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-05 13:51 +0200
              Re: The problem of simultaneity Thomas Heger <ttt_heg@web.de> - 2025-10-07 10:31 +0200
                Re: The problem of simultaneity "Paul B. Andersen" <relativity@paulba.no> - 2025-10-08 21:58 +0200
    Re: The problem of simultaneity Python <jpierre.messager@gmail.com> - 2025-10-01 07:45 +0000
    Re: The problem of simultaneity wugi <wugi@brol.invalid> - 2025-10-13 10:19 -0300
      Re: The problem of simultaneity Maciej Woźniak <mlwozniak@wp.pl> - 2025-10-13 15:43 +0200
      Re: The problem of simultaneity Richard Hachel <rh@tiscali.fr> - 2025-10-13 13:47 +0000
      Re: The problem of simultaneity Jay Wojewódzki <jeazwak@kj.pl> - 2025-10-13 16:55 +0000

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#666668

On 10/15/2025 9:15 PM, Python wrote:
> Le 15/10/2025 à 20:49, Maciej Woźniak a écrit :
>> On 10/15/2025 8:05 PM, Paul B. Andersen wrote:
>>> Den 15.10.2025 09:44, skrev Thomas Heger:
>>>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
>>>
>>>>>
>>>>> What the display on a 'clock' shows is a 'point in time'.
>>>>>
>>>>> I can say that the 'time' now is October 13, 2025, 14:34:32 CET
>>>>> That's 'a point in time'.
>>>>>
>>>>> If I left my home at   t1 = October 13, 2025, 7:05:10 CET
>>>>> and arrived at work at t2 = October 13, 2025, 7:59:50 CET
>>>>> Then I can say that the 'time' I used to walk to work today
>>>>> was 54 minutes and 40 seconds.  (Δt = t2 - t1)
>>>>> That's a duration (or 'interval').
>>>>>
>>>>> So "time" can be both 'a point in time' and a duration.
>>>>
>>>> No: a point in time is also a duration, but where the reference 
>>>> point (= the beginning of the interval) is assumed to be known already.
>>> You _know_ that we in the western world specifies "points in time"
>>> with the Gregorian calendar and the time zones based on UTC.
>>
>> You don't _know_ that's exactly what
>> [A.E.] has denied [...]
> 
> Oh really? Where did he do that?
> 
> 

Oh, really. He did it with his moronic SR
shit.
Tell me, BTW, poor stinker - we have twins.
They were born 2125-10-16. One of them
started his travel 2145-10-16 and
returned 2165-10-16 (from the point of
view of the first one). His "proper
differently" clock has counted 15 years
from start to landing, is the date
of landing 2060-10-16 "from his point
of view"?

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#666669

On 10/16/2025 8:14 AM, Maciej Woźniak wrote:
> On 10/15/2025 9:15 PM, Python wrote:
>> Le 15/10/2025 à 20:49, Maciej Woźniak a écrit :
>>> On 10/15/2025 8:05 PM, Paul B. Andersen wrote:
>>>> Den 15.10.2025 09:44, skrev Thomas Heger:
>>>>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
>>>>
>>>>>>
>>>>>> What the display on a 'clock' shows is a 'point in time'.
>>>>>>
>>>>>> I can say that the 'time' now is October 13, 2025, 14:34:32 CET
>>>>>> That's 'a point in time'.
>>>>>>
>>>>>> If I left my home at   t1 = October 13, 2025, 7:05:10 CET
>>>>>> and arrived at work at t2 = October 13, 2025, 7:59:50 CET
>>>>>> Then I can say that the 'time' I used to walk to work today
>>>>>> was 54 minutes and 40 seconds.  (Δt = t2 - t1)
>>>>>> That's a duration (or 'interval').
>>>>>>
>>>>>> So "time" can be both 'a point in time' and a duration.
>>>>>
>>>>> No: a point in time is also a duration, but where the reference 
>>>>> point (= the beginning of the interval) is assumed to be known 
>>>>> already.
>>>> You _know_ that we in the western world specifies "points in time"
>>>> with the Gregorian calendar and the time zones based on UTC.
>>>
>>> You don't _know_ that's exactly what
>>> [A.E.] has denied [...]
>>
>> Oh really? Where did he do that?
>>
>>
> 
> Oh, really. He did it with his moronic SR
> shit.
> Tell me, BTW, poor stinker - we have twins.
> They were born 2125-10-16. One of them
> started his travel 2145-10-16 and
> returned 2165-10-16 (from the point of
> view of the first one). His "proper
> differently" clock has counted 15 years
> from start to landing, is the date
> of landing 2060-10-16 "from his point
> of view"?

A typo -I meant  2160-10-16, of course.

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#666666

Am Mittwoch000015, 15.10.2025 um 20:05 schrieb Paul B. Andersen:
> Den 15.10.2025 09:44, skrev Thomas Heger:
>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
> 
>>>
>>> What the display on a 'clock' shows is a 'point in time'.
>>>
>>> I can say that the 'time' now is October 13, 2025, 14:34:32 CET
>>> That's 'a point in time'.
>>>
>>> If I left my home at   t1 = October 13, 2025, 7:05:10 CET
>>> and arrived at work at t2 = October 13, 2025, 7:59:50 CET
>>> Then I can say that the 'time' I used to walk to work today
>>> was 54 minutes and 40 seconds.  (Δt = t2 - t1)
>>> That's a duration (or 'interval').
>>>
>>> So "time" can be both 'a point in time' and a duration.
>>
>> No: a point in time is also a duration, but where the reference point 
>> (= the beginning of the interval) is assumed to be known already.
> You _know_ that we in the western world specifies "points in time"
> with the Gregorian calendar and the time zones based on UTC.

Sure, but we could actually use all the other Popes, too, and could use 
their calendars, if we wished to do that.

So: UTC is just one selection from a plethora of possibilities.

> 
>>>
>>> If we are only interested in durations, we may choose to
>>> use a clock we can set to zero at any time.
> 
> We are free to choose our time scale any way we want.
> But it must be precisely defined, it is not 'given by nature'.
> 
> Gregorian calendar and time zones based on UTC is
> what 'everybody' uses in their everyday life.

No, that is absolutely not true.

We have actually several time systems in use today.

Among the more important ones are the calendars of the Jews and the Muslims.


> You use your wristwatch to meet at work at the right
> 'point in time', don't you?

Well, sometimes.

Most of the time I use actually a different kind of clocks, which are 
based upon a timing signal, which gets broadcasted by some agency in 
Germany.>
> But for scientific work, we will probably use other definitions of
> our time.

Sure, but not because our needs are higher, but because time has nothing 
to do with clocks.

...


TH

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#666671

On Thu, 16 Oct 2025 07:02:35 +0200, Thomas Heger <ttt_heg@web.de>
wrote:

>Am Mittwoch000015, 15.10.2025 um 20:05 schrieb Paul B. Andersen:
>> Den 15.10.2025 09:44, skrev Thomas Heger:
>>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
>> 
>>>>
>>>> What the display on a 'clock' shows is a 'point in time'.
>>>>
>>>> I can say that the 'time' now is October 13, 2025, 14:34:32 CET
>>>> That's 'a point in time'.
>>>>
>>>> If I left my home at   t1 = October 13, 2025, 7:05:10 CET
>>>> and arrived at work at t2 = October 13, 2025, 7:59:50 CET
>>>> Then I can say that the 'time' I used to walk to work today
>>>> was 54 minutes and 40 seconds.  (?t = t2 - t1)
>>>> That's a duration (or 'interval').
>>>>
>>>> So "time" can be both 'a point in time' and a duration.
>>>
>>> No: a point in time is also a duration, but where the reference point 
>>> (= the beginning of the interval) is assumed to be known already.
>> You _know_ that we in the western world specifies "points in time"
>> with the Gregorian calendar and the time zones based on UTC.
>
>Sure, but we could actually use all the other Popes, too, and could use 
>their calendars, if we wished to do that.
>
>So: UTC is just one selection from a plethora of possibilities.
>
>> 
>>>>
>>>> If we are only interested in durations, we may choose to
>>>> use a clock we can set to zero at any time.
>> 
>> We are free to choose our time scale any way we want.
>> But it must be precisely defined, it is not 'given by nature'.
>> 
>> Gregorian calendar and time zones based on UTC is
>> what 'everybody' uses in their everyday life.
>
>No, that is absolutely not true.
>
>We have actually several time systems in use today.
>
>Among the more important ones are the calendars of the Jews and the Muslims.
>
>
>> You use your wristwatch to meet at work at the right
>> 'point in time', don't you?
>
>Well, sometimes.
>
>Most of the time I use actually a different kind of clocks, which are 
>based upon a timing signal, which gets broadcasted by some agency in 
>Germany.>
>> But for scientific work, we will probably use other definitions of
>> our time.
>
>Sure, but not because our needs are higher, but because time has nothing 
>to do with clocks.

what? if you ask someone "What time do you have?", don't you expect
them to look at their clock????

>
>...
>
>
>TH

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#666673

Den 16.10.2025 07:02, skrev Thomas Heger:
> Am Mittwoch000015, 15.10.2025 um 20:05 schrieb Paul B. Andersen:
>> Den 15.10.2025 09:44, skrev Thomas Heger:
>>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
>>>>
>>>> So "time" can be both 'a point in time' and a duration.
>>>
>>> No: a point in time is also a duration, but where the reference point 
>>> (= the beginning of the interval) is assumed to be known already.

>> You _know_ that we in the western world specifies "points in time"
>> with the Gregorian calendar and the time zones based on UTC.
> 
> Sure, 

So you know that "time" can be 'a point in time',
and 'a point in time' is no 'duration'.

So why do you keep protesting?

> but we could actually use all the other Popes, too, and could use 
> their calendars, if we wished to do that.

Sure.

> 
> So: UTC is just one selection from a plethora of possibilities.
> 

All countries are using the time zones based on UTC.

>> We are free to choose our time scale any way we want.
>> But it must be precisely defined, it is not 'given by nature'.
>>
>> Gregorian calendar and time zones based on UTC is
>> what 'everybody' uses in their everyday life.
> 
> No, that is absolutely not true.
> 
> We have actually several time systems in use today.
> 
> Among the more important ones are the calendars of the Jews and the 
> Muslims.

So let we rephrase:
Time zones based on UTC is what 'everybody' uses
in their everyday life.

> 
> 
>> You use your wristwatch to meet at work at the right
>> 'point in time', don't you?
> 
> Well, sometimes.
> 
> Most of the time I use actually a different kind of clocks, which are 
> based upon a timing signal, which gets broadcasted by some agency in 
> Germany.

That's probably DCF77.
It sends the time CET (UTC+1H), and it sends the date
according to the Gregorian calendar.

So you _always_ use a clock showing the time CET, and
the Gregorian calendar to meet at work at the right 'point in time'.

>> But for scientific work, we will probably use other definitions of
>> our time.

Like when we define the coordinate time in a frame of reference.

> 
> Sure, but not because our needs are higher, but because time has nothing 
> to do with clocks.

Isn't this a rather silly remark when we just have established
that you are using a clock to find "the point in time"?


We have now settled that you know that "time" can be
both 'a point in time' and a duration.


---------------------------------

Is there any particular reason why you haven't
responded to the following?

Not even you can be so ignorant and stupid that you don't
understand the following scenario:

Remember, this scenario happens in the real world.
Read it again and allow your self think!

Consider the following scenario:
Given an Euclidean space where the axes are called x, y and z.
A is a point at x = 0, y = 0 and z = 0.
B is a point at x = L, y = 0 and z = 0.
Clock Ca is placed at A and another, equal clock Cb is at B.
The two clocks simultaneously show the same; they are synchronous.
An object is moving at constant speed from A to B.
When the object is at A clock Ca shows t = ta.
When the object is at B clock Cb shows t = tb.

At t = ta, object O at A

   Ca = ta                     Cb = ta
   A                           B
  -|---------------------------|---------> x
   0                           L
   O


At t = tb, object O at B

   Ca = tb                     Cb = tb
   A                           B
  -|---------------------------|---------> x
   0                           L
                               O
In case your editor clutters up the figure:
https://paulba.no/temp/Fig1.pdf


The time the object used to travel from A to B is Δt = tb - ta.
The object was moving at the speed v = L/Δt = L/(tb - ta).

Note that the above is equally true according Newtonian Mechanics
and according to The Special Theory of Relativity (SRT).

So is there no difference between NM and SR?

Of course it is.
In NM the Δt is 'absolute' in the sense that it is independent
of frames of reference.

So what about SR?

The metric below defines SR. So what can be deduced from this
metric is what SR predicts. This is indisputable.

   (c⋅dτ)² = (c⋅dt)² − dx² − dy² − dz²                    (1)
or:
   dτ² = (1 − (1/c²)⋅[(dx/dt)² + (dy/dt)² + (dz/dt)²])dt² (2)
or:
   dτ = √(1 − v²/c²)dt                                    (3)
   where v² = (dx/dt)² + (dy/dt)² + (dz/dt)²

(1), (2) and (3)  are the same metric.

Let's calculate the proper time of a clock that is moving from
the event    E1: t =  0, x = 0, y = 0, z = 0
to the Event E2: t = Δt, x = 0, y = 0, z = 0

According to (3): v = 0
  τ = ∫(from t=0 to t=Δt)dt = Δt

But what would it be in the frame of reference K' (t',x',z') ?

Note that the metric (1) is true for any frame of reference
So:
  (c⋅dτ)² = (c⋅dt')² −dx'² −dy'² −dz'²
and:
  (c⋅dτ)² = (c⋅dt)² −dx² −dy² −dz² = (c⋅dt')² −dx'² −dy'² −dz'²
note:
  this does _not_ mean that t = t', x = x', y = y' and z = z'

Let the origin of K' move along the positive x-axis of K
with the speed v.
The events E1 and E2 will then have the coordinates in K':
E1: t' =   0, x' = 0,    y' = 0, z' = 0
E2: t' = Δt', x' = v⋅t', y' = 0, z' = 0

Note that v = dx'/dt' and v² = (dx'/dt')²
So according to (3):
dτ = √(1 − v²/c²)dt'
τ = ∫(from t'=0 to t'= Δt') √(1 − v²/c²)dt' = √(1 − v²/c²)Δt'

The proper time between two events is invariant
so: τ = Δt = √(1 − v²/c²)Δt'

The temporal interval between E1 and E2 is Δt in K
The temporal interval between E1 and E2 is Δt/√(1 − v²/c²) in K'
The temporal intervals between the same two events are
different in K and K'.

Temporal intervals between events are not absolute,
they are frame dependent.
(Note that Δt and Δt' are _not_ proper times.)

-- 
Paul

https://paulba.no/

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#666674

> Le 16/10/2025 à 19:39, "Paul B. Andersen" a écrit :

> Temporal intervals between events are not absolute,
> they are frame dependent.



> Il y a déjà quarante ans je disais que la théorie de la relativité était 
> vraie, 
> mais terriblement mal comprise.
> Je n'ai pas changé d'avis, et je remarque que les physiciens de leur côté ne 
> démordent pas du fait qu'ils ont mieux compris les choses que moi. 
> 
> La réalité est quand même tout autre.
> 
> Je le répète, ce n'est pas que les choses sont fausses ; mais elles sont 
> terriblement mal dites et mal comprises, d'où les paradoxes débiles qui 
> ressurgissent sans cesse (paradoxe de Langevin, paradoxe d'Andromède, paradoxe 
> d'Ehrenfest, paradoxe du garage).  
> 
> Pourtant, chose incroyable, voire miraculeuse au sens propre du mot miracle 
> (signe de quelque chose de grandiose), le dire, c'est comme souffler de la bouche 
> sur les ailes d'un moulin à vent. 
> 
> Je vais préciser cependant une chose que je redis depuis quarante ans : "La 
> notion de simultanéité est absolue pour deux observateurs qui se croisent; ils 
> perçoivent exactement le même univers présent". Chose que les physiciens nient 
> sans comprendre vraiment de quoi ils causent, et simplement parce que n'y ayant 
> pas réfléchi par eux mêmes, ils en ont appris les mathématiques tels quels 
> sans les appliquer au réel.
> 
> C'est pourtant très simple pour qui veut se donner la peine d'évoluer un peu 
> plus haut.
> 
> Un observateur est dans le train, immobile (c'est la voie qui se déplace sous 
> lui) et au milieu d'un wagon. Il perçoit simultanément deux éclairs qui de sont 
> donc produits à égale distance de lui-même, sur la roue avant et sur la roue 
> arrière. 
>  
> Les physiciens se mettent alors à penser que le piéton, sur le bord, va lui 
> aussi percevoir les deux éclairs, mais pas en même temps. Cela est faux. La 
> théorie bien comprise est évidente, il percevra les deux éclairs dans sa 
> rétine de façon simultanée. 
> 
> Simultanéité parfaite pour les deux. C'est exactement où conduisent les 
> transformations de Poincaré si on les comprend clairement et qu'on sort de ce 
> bloc-espace-temsp bidon et grotesque inventé par Minkowski.
> 
> Mais quelque chose se passe pour l'observateur-piéton. Certes les éclairs sont 
> simultanés (il les perçoit en même temps) mais il ne les perçoit pas à 
> distances égales. La roue avant du wagon où frappe l'éclair 
> lui parait bien plus proche que le même effet sur la roue arrière. 
> 
> Je remets ici deux petits dessins que j'avais fait il y a de nombreuses années, 
> en pure perte, mais qui expliquaient pourtant beaucoup mieux les choses que tout 
> ce que vous pouvez voir sur le sujet sur usenet ou sur Youtube.  
> 
> Ce sont deux dessins miraculeux (dans le sens du terme : signe grandiose).
> 
> Non pas parce que c'est vrai (bien sûr que oui, c'est vrai), non pas parce que 
> c'est admirablement dessiné (tu parles, Charles), c'est pas en ça que c'est 
> grandiose et miraculeux.
> 
> C'est parce que ça montre l'immense connerie humaine dans le sens où ne 
> comprenant pas ces deux dessins, on se met à cracher dessus.
> 
> Et ça, c'est franchement miraculeux.
> 
> <http://nemoweb.net/jntp?91KLbtIoNCNz7VkYGHRmN7L--s4@jntp/Data.Media:1>
> 
> <http://nemoweb.net/jntp?91KLbtIoNCNz7VkYGHRmN7L--s4@jntp/Data.Media:2>
 
 Bonne soirée. 


 R.H. 

-- 
Ce message a été posté avec Nemo : <https://www.nemoweb.net/?DataID=tCBCCvcwD2c9arZIMQ9KQA7H4q4@jntp>

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#666716

Den 16.10.2025 19:51, skrev Richard Hachel:
> 
> Forty years ago, I said that the theory of relativity was true, but terribly 
> misunderstood. I haven't changed my mind, and I notice that physicists, for 
> their part, are adamant that they understand things better than I do.
> The reality is, however, quite different.
> 
> I repeat, it's not that things are false; but that they are terribly misspoken 
> and misunderstood, hence the stupid paradoxes that constantly resurface 
> (Langevin's paradox, Andromeda paradox, Ehrenfest paradox, garage paradox).
> 

The Special Theory of Relativity (SR) is precisely defined
by the metric:
      (c⋅dτ)² = (c⋅dt)² − dx² − dy² − dz²

What follows from this metric is what SR predicts.

See:
https://paulba.no/pdf/TwinsByMetric.pdf

see: 2.4 Concrete example
-------------------------
Twin A stays not be interpreted inertial
Twin B travel 10 ly and back with constant acceleration 1c/year
Twin A ages 23.664 years
Twin B ages  9.912 years

This follows inevitably from the metric,
so it is a _fact_ that this is what SR predicts.

There is nothing to "explain".

Your opinion is irrelevant.

-- 
Paul

https://paulba.no/

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#666717

Den 18.10.2025 11:39, skrev Paul B. Andersen:
> See:
> https://paulba.no/pdf/TwinsByMetric.pdf
> 
> see: 2.4 Concrete example
> -------------------------
> Twin A stays not be interpreted inertial

Typo:

Twin A stays inertial

> Twin B travel 10 ly and back with constant acceleration 1c/year
> Twin A ages 23.664 years
> Twin B ages  9.912 years
> 
> This follows inevitably from the metric,
> so it is a _fact_ that this is what SR predicts.
> 
> There is nothing to "explain".
> 
> Your opinion is irrelevant.
> 


-- 
Paul

https://paulba.no/

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#666721

On 10/18/2025 11:43 AM, Paul B. Andersen wrote:
> Den 18.10.2025 11:39, skrev Paul B. Andersen:
>> See:
>> https://paulba.no/pdf/TwinsByMetric.pdf
>>
>> see: 2.4 Concrete example
>> -------------------------
>> Twin A stays not be interpreted inertial
> 
> Typo:
> 
> Twin A stays inertial

Paul poor trash, we have g on Earth, what is
the acceleration of the second twins?

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#666718

On 10/18/2025 11:39 AM, Paul B. Andersen wrote:
> Den 16.10.2025 19:51, skrev Richard Hachel:
>>
>> Forty years ago, I said that the theory of relativity was true, but 
>> terribly misunderstood. I haven't changed my mind, and I notice that 
>> physicists, for their part, are adamant that they understand things 
>> better than I do.
>> The reality is, however, quite different.
>>
>> I repeat, it's not that things are false; but that they are terribly 
>> misspoken and misunderstood, hence the stupid paradoxes that 
>> constantly resurface (Langevin's paradox, Andromeda paradox, Ehrenfest 
>> paradox, garage paradox).
>>
> 
> The Special Theory of Relativity (SR) is precisely defined
> by the metric:
>       (c⋅dτ)² = (c⋅dt)² − dx² − dy² − dz²

Only such an idiot can believe such a nonsensical
lie.

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#666729

Le 18/10/2025 à 11:37, "Paul B. Andersen" a écrit :
> Den 16.10.2025 19:51, skrev Richard Hachel:
> 
> see: 2.4 Concrete example
> -------------------------
> Twin A stays not be interpreted inertial
> Twin B travel 10 ly and back with constant acceleration 1c/year
> Twin A ages 23.664 years
> Twin B ages  9.912 years
> 
> This follows inevitably from the metric,
> so it is a _fact_ that this is what SR predicts.
> 
> There is nothing to "explain".
> 
> Your opinion is irrelevant.

To fully understand the theory of relativity, we must begin with the 
Poincaré-Lorentz transformations and visualize as precisely as possible 
what they imply in our minds.
To research these transformations, there are two simple methods: the one 
used by Henri Poincaré and Richard Hachel (known as the French method) 
and the one used by Albert Einstein and Hermann Minkowski (known as the 
Mittleuropa method).
The first involves observing a train car moving from left to right; the 
second involves imagining oneself in the train car and observing the 
landscape moving from right to left.
The transformations are then said to be positive or negative. In positive 
form (Poincaré, Hachel), we have:
x'=(x+v.To)/sqrt(1-Vo²/c²)
y'=y
z'=z'
t'=(t+x.Vo/c²)/sqrt(1-Vo²/c²)
In negative form, we have:
x'=(x-v.To)/sqrt(1-Vo²/c²)
y'=y
z'=z'
t'=(t-x.Vo/c²)/sqrt(1-Vo²/c²)
It's just the same thing, said differently.

But from this point on, we disagree.

Einstein's concepts then lead to equations and results that are different 
from mine.

For example, here, in the quantification of times measured during 
accelerations, where I give a slightly longer time each time, explaining 
that we should not measure the length of the blue curve on the Cartesian 
reference frame, but the red segment in continuous rotation during 
acceleration (the speed being continuously increasing).

<http://nemoweb.net/jntp?8DMHYu6uoHCkQXN3gk5nBM5BXIM@jntp/Data.Media:1>

<http://nemoweb.net/jntp?8DMHYu6uoHCkQXN3gk5nBM5BXIM@jntp/Data.Media:2>

R.H. 

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#666741

Den 18.10.2025 15:37, skrev Richard Hachel:
> Le 18/10/2025 à 11:37, "Paul B. Andersen" a écrit :
>>
>> see: 2.4 Concrete example
>> -------------------------
>> Twin A stays inertial
>> Twin B travel 10 ly and back with constant acceleration 1c/year
>> Twin A ages 23.664 years
>> Twin B ages  9.912 years
>>
>> This follows inevitably from the metric,
>> so it is a _fact_ that this is what SR predicts.
>>
>> There is nothing to "explain".
>>
>> Your opinion is irrelevant.

You snipped this:

The Special Theory of Relativity (SR) is precisely defined
by the metric:
      (c⋅dτ)² = (c⋅dt)² − dx² − dy² − dz²

What follows from this metric is what SR predicts.

See:
https://paulba.no/pdf/TwinsByMetric.pdf

Read it, and you will see that it is a fact that
in the scenario described in 2.4 Concrete example,
The Special Theory of Relativity predicts that
twin A ages 23.664 years while twin B ages  9.912 years

> 
> To fully understand the theory of relativity, we must begin with the 
> Poincaré-Lorentz transformations and visualize as precisely as possible 
> what they imply in our minds.

The Lorentz transformation follows from the metric, and give
the same answer to my scenario above, namely that
twin A ages 23.664 years while twin B ages  9.912 years.

It is not possible to make SR predict anything else than the above.

It is nothing to "research" or "understand", the prediction above
follows from the metric (and thus from the Lorentz transform).
It is plain and simple mathematics.

Since you think SR predicts otherwise than it factually does,
you are wrong.


> To research these transformations, there are two simple methods: the one 
> used by Henri Poincaré and Richard Hachel (known as the French method) 
> and the one used by Albert Einstein and Hermann Minkowski (known as the 
> Mittleuropa method).
> The first involves observing a train car moving from left to right; the 
> second involves imagining oneself in the train car and observing the 
> landscape moving from right to left.
> The transformations are then said to be positive or negative. In 
> positive form (Poincaré, Hachel), we have:
> x'=(x+v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t+x.Vo/c²)/sqrt(1-Vo²/c²)
> In negative form, we have:
> x'=(x-v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t-x.Vo/c²)/sqrt(1-Vo²/c²)
> It's just the same thing, said differently.
> 
> But from this point on, we disagree.
> 
> Einstein's concepts then lead to equations and results that are 
> different from mine.
> 
> For example, here, in the quantification of times measured during 
> accelerations, where I give a slightly longer time each time, explaining 
> that we should not measure the length of the blue curve on the Cartesian 
> reference frame, but the red segment in continuous rotation during 
> acceleration (the speed being continuously increasing).

You should read:
https://paulba.no/pdf/TwinsByMetric.pdf
The math is correct.

Your math is simply wrong.
You are ignorant of elementary calculus.

-- 
Paul

https://paulba.no/

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#666759

Den 18.10.2025 15:37, skrev Richard Hachel:
> 
> To fully understand the theory of relativity, we must begin with the 
> Poincaré-Lorentz transformations and visualize as precisely as possible 
> what they imply in our minds.
> To research these transformations, there are two simple methods: the one 
> used by Henri Poincaré and Richard Hachel (known as the French method) 
> and the one used by Albert Einstein and Hermann Minkowski (known as the 
> Mittleuropa method).
> The first involves observing a train car moving from left to right; the 
> second involves imagining oneself in the train car and observing the 
> landscape moving from right to left.

The Lorentz transform is a coordinate transformation
from one frame of reference to another.
So we must obviously start with defining the frames
of references, and how they move relative to each other.
Let the frames be called K(t,x,y,z) and K'(t',x',y',z').

If we let the axes be parallel (x||x',y||y',z||z'),
let the origins be aligned at t = t'= 0, and let
the motion be along the x axes, we will have two variants:

In the following is γ = 1/√(1−v²/c²)

#1: The origin of K' is moving along the positive x-axis
     of K with the speed v.
  t' = γ(t - (v/c²)⋅x)
  x' = γ(x - v⋅t)
  y' = y
  z' = z

The inverse transform:
  t = γ(t' + (v/c²)⋅x')
  x = γ(x' + v⋅t')
  y = y'
  z = z'

#2: The origin of K is moving along the positive x'-axis
     of K' with the speed v.
  t' = γ(t + (v/c²)⋅x)
  x' = γ(x + v⋅t)
  y' = y
  z' = z

The inverse transform:
  t = γ(t' - (v/c²)⋅x')
  x = γ(x' - v⋅t')
  y = y'
  z = z'

It is nonsense to call #1 and #2 "different methods".
The difference is a trivial change of direction of the motion.

When you call them "different methods" you haven't understood
that the difference is only a change in direction of the motion.


> The transformations are then said to be positive or negative. In 
> positive form (Poincaré, Hachel), we have:
> x'=(x+v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t+x.Vo/c²)/sqrt(1-Vo²/c²)

The above is a coordinate transformation from
the frame (t,x,y,z) to (t',x',y',z')

> In negative form, we have:
> x'=(x-v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t-x.Vo/c²)/sqrt(1-Vo²/c²)

The above is a _different_ coordinate transformation
from the frame (t,x,y,z) to (t',x',y',z')

> It's just the same thing, said differently.

No. It's simply wrong!
You can't have two different coordinate transformations
between the same two frames of reference.

Your failure to define the frames of reference properly
shows that you don't know what you are doing.

-- 
Paul

https://paulba.no/

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#666773

On 10/19/2025 9:02 PM, Paul B. Andersen wrote:
> Den 18.10.2025 15:37, skrev Richard Hachel:
>>
>> To fully understand the theory of relativity, we must begin with the 
>> Poincaré-Lorentz transformations and visualize as precisely as 
>> possible what they imply in our minds.
>> To research these transformations, there are two simple methods: the 
>> one used by Henri Poincaré and Richard Hachel (known as the French 
>> method) and the one used by Albert Einstein and Hermann Minkowski 
>> (known as the Mittleuropa method).
>> The first involves observing a train car moving from left to right; 
>> the second involves imagining oneself in the train car and observing 
>> the landscape moving from right to left.
> 
> The Lorentz transform is a coordinate transformation
> from one frame of reference to another.
> So we must obviously start with defining the frames
> of references, and how they move relative to each other.
> Let the frames be called K(t,x,y,z) and K'(t',x',y',z').
> 
> If we let the axes be parallel (x||x',y||y',z||z'),
> let the origins be aligned at t = t'= 0, and let
> the motion be along the x axes, we will have two variants:

Fortunately, we have GPS now, so we can be
absolutely sure that the delusions of
relativistic idiots have nothing in common
with real clocks, real time, real coordinates
or real anything.

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#666730

Le 18/10/2025 à 11:37, "Paul B. Andersen" a écrit :
> Den 16.10.2025 19:51, skrev Richard Hachel:
> 
> see: 2.4 Concrete example
> -------------------------
> Twin A stays not be interpreted inertial
> Twin B travel 10 ly and back with constant acceleration 1c/year
> Twin A ages 23.664 years
> Twin B ages  9.912 years
> 
> This follows inevitably from the metric,
> so it is a _fact_ that this is what SR predicts.
> 
> There is nothing to "explain".
> 
> Your opinion is irrelevant.

To fully understand the theory of relativity, we must begin with the 
Poincaré-Lorentz transformations and visualize as precisely as possible 
what they imply in our minds.
To research these transformations, there are two simple methods: the one 
used by Henri Poincaré and Richard Hachel (known as the French method) 
and the one used by Albert Einstein and Hermann Minkowski (known as the 
Mittleuropa method).
The first involves observing a train car moving from left to right; the 
second involves imagining oneself in the train car and observing the 
landscape moving from right to left.
The transformations are then said to be positive or negative. In positive 
form (Poincaré, Hachel), we have:
x'=(x+v.To)/sqrt(1-Vo²/c²)
y'=y
z'=z'
t'=(t+x.Vo/c²)/sqrt(1-Vo²/c²)
In negative form, we have:
x'=(x-v.To)/sqrt(1-Vo²/c²)
y'=y
z'=z'
t'=(t-x.Vo/c²)/sqrt(1-Vo²/c²)
It's just the same thing, said differently.

But from this point on, we disagree.

Einstein's concepts then lead to equations and results that are different 
from mine.

For example, here, in the quantification of times measured during 
accelerations, where I give a slightly longer time each time, explaining 
that we should not measure the length of the blue curve on the Cartesian 
reference frame, but the red segment in continuous rotation during 
acceleration (the speed being continuously increasing).

<http://nemoweb.net/jntp?cUOgry3RjOvfF7U3wksGGjii-Sk@jntp/Data.Media:1>

<http://nemoweb.net/jntp?cUOgry3RjOvfF7U3wksGGjii-Sk@jntp/Data.Media:2>

R.H. 

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#666731

Le 18/10/2025 à 15:39, Richard Hachel  a écrit :
> Le 18/10/2025 à 11:37, "Paul B. Andersen" a écrit :
>> Den 16.10.2025 19:51, skrev Richard Hachel:
>> 
>> see: 2.4 Concrete example
>> -------------------------
>> Twin A stays not be interpreted inertial
>> Twin B travel 10 ly and back with constant acceleration 1c/year
>> Twin A ages 23.664 years
>> Twin B ages  9.912 years
>> 
>> This follows inevitably from the metric,
>> so it is a _fact_ that this is what SR predicts.
>> 
>> There is nothing to "explain".
>> 
>> Your opinion is irrelevant.
> 
> To fully understand the theory of relativity, we must begin with the 
> Poincaré-Lorentz transformations and visualize as precisely as possible what they 
> imply in our minds.
> To research these transformations, there are two simple methods: the one used by 
> Henri Poincaré and Richard Hachel (known as the French method) and the one used 
> by Albert Einstein and Hermann Minkowski (known as the Mittleuropa method).
> The first involves observing a train car moving from left to right; the second 
> involves imagining oneself in the train car and observing the landscape moving 
> from right to left.
> The transformations are then said to be positive or negative. In positive form 
> (Poincaré, Hachel), we have:
> x'=(x+v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t+x.Vo/c²)/sqrt(1-Vo²/c²)
> In negative form, we have:
> x'=(x-v.To)/sqrt(1-Vo²/c²)
> y'=y
> z'=z'
> t'=(t-x.Vo/c²)/sqrt(1-Vo²/c²)
> It's just the same thing, said differently.
> 
> But from this point on, we disagree.
> 
> Einstein's concepts then lead to equations and results that are different from 
> mine.
> 
> For example, here, in the quantification of times measured during accelerations, 
> where I give a slightly longer time each time, explaining that we should not 
> measure the length of the blue curve on the Cartesian reference frame, but the red 
> segment in continuous rotation during acceleration (the speed being continuously 
> increasing).
> 
> <http://nemoweb.net/jntp?cUOgry3RjOvfF7U3wksGGjii-Sk@jntp/Data.Media:1>
> 
> <http://nemoweb.net/jntp?cUOgry3RjOvfF7U3wksGGjii-Sk@jntp/Data.Media:2>
> 
> R.H. 


 <https://www.nemoweb.net/?DataID=YMBZaAA_KlLq9csvn2-nJPEFWkM@jntp>

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#666733

Le 18/10/2025 à 15:39, Richard Hachel  a écrit :
> Le 18/10/2025 à 11:37, "Paul B. Andersen" a écrit :
>> Den 16.10.2025 19:51, skrev Richard Hachel:
>> 
>> see: 2.4 Concrete example
>> -------------------------
>> Twin A stays not be interpreted inertial
>> Twin B travel 10 ly and back with constant acceleration 1c/year
>> Twin A ages 23.664 years
>> Twin B ages  9.912 years
>> 
>> This follows inevitably from the metric,
>> so it is a _fact_ that this is what SR predicts.
>> 
>> There is nothing to "explain".
>> 
>> Your opinion is irrelevant.
> 
> To fully understand the theory of relativity, we must begin with the 
> Poincaré-Lorentz transformations and visualize as precisely as possible what they 
> imply in our minds.
> To research these transformations, there are two simple methods: the one used by 
> Henri Poincaré and Richard Hachel (known as the French method) and the one used 
> by Albert Einstein and Hermann Minkowski (known as the Mittleuropa method).

This is utterly asinine. You made up all of this.

Nothing of this kind is "known".

When it comes to Relativity Poincaré, Einstein, Lorentz, Minkowski are 
relevant and stated basically concording results. You are not relevant.

If you read what Poincaré actally wrote (you didn't) you'll see that he 
is very close to Minkowki's point of view.

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#666732

Paul B. Andersen wrote:

> Den 16.10.2025 19:51, skrev Richard Hachel:
>> I repeat, it's not that things are false; but that they are terribly
>> misspoken and misunderstood, hence the stupid paradoxes that constantly
>> resurface (Langevin's paradox, Andromeda paradox, Ehrenfest paradox,
>> garage paradox).
>> 
> The Special Theory of Relativity (SR) is precisely defined by the
> metric:       (c⋅dτ)² = (c⋅dt)² − dx² − dy² − dz²
> 
> What follows from this metric is what SR predicts.
> See: https://paulba.no/pdf/TwinsByMetric.pdf

good you mention it. The y and z directions are also insignificant, since 
the relativity effects are along a straight line between the target and 
observer. That it move a bit to left or right means nothing in SR

good point, I challenge you.

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#666675

On 10/16/2025 7:42 PM, Paul B. Andersen wrote:
> Den 16.10.2025 07:02, skrev Thomas Heger:
>> Am Mittwoch000015, 15.10.2025 um 20:05 schrieb Paul B. Andersen:
>>> Den 15.10.2025 09:44, skrev Thomas Heger:
>>>> Am Montag000013, 13.10.2025 um 21:59 schrieb Paul B. Andersen:
>>>>>
>>>>> So "time" can be both 'a point in time' and a duration.
>>>>
>>>> No: a point in time is also a duration, but where the reference 
>>>> point (= the beginning of the interval) is assumed to be known already.
> 
>>> You _know_ that we in the western world specifies "points in time"
>>> with the Gregorian calendar and the time zones based on UTC.
>>
>> Sure, 
> 
> So you know that "time" can be 'a point in time',
> and 'a point in time' is no 'duration'.
> 
> So why do you keep protesting?
> 
>> but we could actually use all the other Popes, too, and could use 
>> their calendars, if we wished to do that.
> 
> Sure.
> 
>>
>> So: UTC is just one selection from a plethora of possibilities.
>>
> 
> All countries are using the time zones based on UTC.
> 
>>> We are free to choose our time scale any way we want.
>>> But it must be precisely defined, it is not 'given by nature'.
>>>
>>> Gregorian calendar and time zones based on UTC is
>>> what 'everybody' uses in their everyday life.
>>
>> No, that is absolutely not true.
>>
>> We have actually several time systems in use today.
>>
>> Among the more important ones are the calendars of the Jews and the 
>> Muslims.
> 
> So let we rephrase:
> Time zones based on UTC is what 'everybody' uses
> in their everyday life.

Of course, they have nothing in common with
your dilating delusions...




> So you _always_ use a clock showing the time CET, and
> the Gregorian calendar to meet at work at the right 'point in time'.
> 

Your moronic cult has been trying to ruin that,
but with no success. Common sense has been
warning.

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#666631

On 2025-10-13 05:59:58 +0000, Thomas Heger said:

> Am Samstag000011, 11.10.2025 um 11:28 schrieb Richard Hachel:
>> Le 11/10/2025 à 09:13, Thomas Heger a écrit :
>> 
>>> Einstein's relativity theory isn't relativistic at all.
>>> 
>>> TH
>> 
>> Yes.
>> It's relativistic.
>> But the problem is that it confuses everything, and it leads to 
>> nonsense if you take it a step too far.
>> For example, Albert Einstein, who is considered a god, was unable to 
>> understand the difference between the relativity of chronotropy
>> and the relativity of durations, which is what Dr. Richard Hachel, who 
>> is considered a crank, does.
>> It's the history of humanity in real life.
>> 
>> Let's take Langevin's traveler as an example; Hachel is very precise 
>> about the terms. On the traveler's return, for example, his chronotropy 
>> beats slower than that of the terrestrial traveler (as on the outward 
>> journey), but his watch nevertheless runs faster.
> 
> 
> I would use other words, but actually had the same impression of 
> Einstein's text.
> 
> I meant that time is always an interval, while Einstein thought about 
> time as linear and countable.
> 
> But usually we use some starting point as reference, while often that 
> isn't mentioned.
> 
> What makes no sense, that are terms like 'bestimmte Ära' (certain era), 
> because eras are not numbered.
> 
> Also this concept of 'linear time' (embedded in 'big-bang theory') is 
> most likely wrong.
> 
> Einstein also used 'external time', which is similar to Newtons 
> 'absolute time', while didn't use Poincare's 'local time'.
> 
> So, in my opinion SRT isn't 'relativistic' enough.

The problem with the word "time" (and many other words) is that in
Common Language it is used for many different meanings. When clearer
expression is desired different words should be used for different
meanings. Often, and in particular for discussing physics, it is
best to restrict the meaning of "time" when used as a nout to
expressions that can be used as an answer to the questions that ask
when someting happens, i.e., values of a time coordinate of an event.
The word "duration" can be used for difference of two times. But even
in physics discussions it is usually assumed that the participants can
understand from context which of the multiple meanings of "time" is
used.

-- 
Mikko

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