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Re: Variable Time and the Variable Speed of Light

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Am 19.09.2018 um 17:43 schrieb Tom Roberts:
> On 9/19/18 9:06 AM, Thomas Heger wrote:
>> the meter is defined by the distance, that light travels through the 
>> vacuum  in a certain (very small) amount of time.
>> So the meter is defined by means of light and a certain interval of time.
> 
> Yes. That interval is 1/299,792,458 second (about 3.33 nanoseconds).
> 
>> This fraction of the second is defined by the time that light needs to 
>> travel a meter through vacuum.
> 
> This last is wrong -- you assumed that you know what a meter is, but 
> using the new definition YOU DON'T KNOW THAT until you determine it (via 
> measurement).
> 
>      That fraction was DEFINED so that the the length of a meter
>      using the new definition differed by as little as possible
>      from the previous definition. The fraction was determined by
>      many measurements of the vacuum speed of light using the old
>      definition.
> 
>> To me this looks VERY much like circular reasoning.
> 
> Only because you phrased it inappropriately.
> 
> There are three inter-related quantities here: the meter, the second, 
> and the vacuum speed of light. We are free to define any two of them, 
> but not all three -- the third must be derived from the two that are 
> defined, via measurement.
>

Actually 'length of the meter' is, what the definition should define.

This already contains implicit assumptions (known to be wrong!):

- one piece (say one cubic meter) of vacuum here is behaving similar to 
one piece of vacuum there (say: one light year away).

- length does not change

- the length of a second does not change

Then we have another implicit assumption in 'speed of light in vacuum'. 
That is 'inertial frame of reference' (stemming from SRT).

But we don't have anything like that here on Earth or even near the 
solar system.

Instead the Earth surface performs circular motions around several axis':
around its own axis
around the Sun
around the center of our Galaxy

We have also gravity, Earth magnetism and lots of em-fields of various 
sources.

This is all supposed to have an influence on light and eventually on 
time, too.

So the definition of the meter is not really a definition.

It is actually a certain way to transfer the original definition to 
other places.

Actually all the SI units are random choices of something, but according 
to a certain systematic approach. The meter was defined as 1/40,000 of 
the meridian through Paris.

The system was a quite clever and had many advantages. Now this length 
was casted into a Platinum bar and that was defining the meter.

Since it was not a very practical method, the new definition of the 
meter uses light.


> There is nothing circular in choosing to define the second and the 
> vacuum speed of light, and then deriving the meter via measurement. 
> There are good metrological reasons for doing it that way, which were 
> accepted back in 1983.
> 
>      Do you seriously think you understand this better than the
>      world's experts? SERIOUSLY????
> 

Physics is in a way 'sick' and the disease is called 'academia'.

This is causing the scientists to base everything they think and say on 
their forefathers and superiors.

So errors (made by any of our ancestors) of any kind are prohibited to 
be considered, unless the scientists wants to loose the job - what they 
usually don't.



TH

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Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-06 01:07 +0200
  Re: Variable Time and the Variable Speed of Light Thomas Heger <ttt_heg@web.de> - 2018-09-19 16:06 +0200
    Re: Variable Time and the Variable Speed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-09-19 10:43 -0500
      Re: Variable Time and the Variable Speed of Light Stakos Netakis <autp@wsalaw.oa> - 2018-09-19 15:56 +0000
      Re: Variable Time and the Variable Speed of Light Thomas Heger <ttt_heg@web.de> - 2018-09-20 06:45 +0200
        Re: Variable Time and the Variable Speed of Light Stakos Netakis <autp@wsalaws.np> - 2018-09-20 16:35 +0000
          Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-21 19:45 +0200
            Re: Variable Time and the Variable Speed of Light Rhett Joyner <udof@rsrrfirw.on> - 2018-09-21 21:41 +0000
              Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-22 00:14 +0200
                Re: Variable Time and the Variable Speed of Light Rhett Joyner <udof@rsrrfirv.on> - 2018-09-21 22:48 +0000
        Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-21 19:43 +0200
          Re: Variable Time and the Variable Speed of Light Thomas Heger <ttt_heg@web.de> - 2018-09-23 16:23 +0200
            Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-23 16:44 +0200
      Re: Variable Time and the Variable Speed of Light alsor@interia.pl - 2018-09-20 11:07 -0700
        Re: Variable Time and the Variable Speed of Light JanPB <filmart@gmail.com> - 2018-09-20 12:16 -0700
          Re: Variable Time and the Variable Speed of Light Jayson Durante <tug@wsedwsa.np> - 2018-09-20 19:43 +0000
          Re: Variable Time and the Variable Speed of Light alsor@interia.pl - 2018-09-20 15:38 -0700
        Re: Variable Time and the Variable Speed of Light Tom Roberts <tjroberts137@sbcglobal.net> - 2018-09-20 23:34 -0500
          Re: Variable Time and the Variable Speed of Light Stakos Netakis <autp@wsalaws.np> - 2018-09-21 09:23 +0000
          Re: Variable Time and the Variable Speed of Light alsor@interia.pl - 2018-09-21 11:25 -0700
            Re: Variable Time and the Variable Speed of Light JanPB <filmart@gmail.com> - 2018-09-21 16:17 -0700
              Re: Variable Time and the Variable Speed of Light alsor@interia.pl - 2018-09-22 10:36 -0700
                Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-22 20:23 +0200
    Re: Variable Time and the Variable Speed of Light Stakos Netakis <autp@wsalaw.oa> - 2018-09-19 15:48 +0000
    Re: Variable Time and the Variable Speed of Light "Dono," <sa_ge@comcast.net> - 2018-09-19 09:19 -0700
      Re: Variable Time and the Variable Speed of Light Stakos Netakis <autp@wsalaws.np> - 2018-09-21 09:58 +0000
    Re: Variable Time and the Variable Speed of Light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2018-09-19 23:43 +0200

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