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Re: Particle Physics

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Am 22.04.2016 20:35, schrieb Tom Roberts:
> On 4/22/16 4/22/16 - 12:49 PM, Thomas Heger wrote:
>> [use of natural units]
>> I regard this behaviour as disgusting!
>
> That says far more about you than about the use of natural units.
>
> It seems you simply do not understand what units actually are. They are
> NOT some mystical quantity that make physical calculations come out
> right. They are simply a standard value to which ratios are made.
>
> So when we say something has a length of 1 meter, what we actually mean
> is that the ratio of its length to the standard length of a meter is 1.

No!

If we take the meter as unit for measurements of the type length, then a 
certain length is a product of a number and the standard unit '1 m'.

It can be a small number or a large number. So we could measure tiny 
distances and extremely large ones with the same unit.

For convenience we could measure atoms in very small units and stars 
with light-years. But that's is not necessary. Meters are possible for 
all possible distances.

To leave out the meter in a measurement would make things difficult, 
since nobody could interpret a certain number (say 453), if we do not 
declare, which kind of units we would like to count with it.

>
>> I cannot real see how physicists justify to sweep the dimensions of a
>> unit under
>> the rug.
>
> No "justification" is needed, and there is no "sweeping", either.
>
> All that is happening is that a more convenient set of standards is
> chosen so that various conversion factors are 1, rather than some
> historical value (such as 299,792,458 m/s for the speed of light in
> vacuum).

Agreed: '1' is much more convenient than '299,792,458'.

But what do have against 'm/s' (or another type of dimension)?

>
>> 1 lightsecond per second as
>> value of c is certainly possible.
>
> Sure. But that is not unitless. The way physicists actually do this is
> to use centimeters for the unit of time, so c becomes 1 cm/cm = 1.
>

I wonder if universities have a special department for caring  about the 
subsequent mental trauma of physics student, after they went through an 
introduction into theoretical physics.


TH

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Particle Physics Carl Susumu <numbernumber1212@gmail.com> - 2016-04-21 17:09 -0700
  Re: Particle Physics Gary Harnagel <hitlong@yahoo.com> - 2016-04-21 19:42 -0700
    Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-22 06:42 +0200
      Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-22 07:14 -0500
        Re: Particle Physics David Fuller <fuller.david@hotmail.com> - 2016-04-22 07:01 -0700
        Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-22 19:49 +0200
          Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-22 13:06 -0500
            Re: Particle Physics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-04-23 01:37 +0200
          Re: Particle Physics Tom Roberts <tjroberts137@sbcglobal.net> - 2016-04-22 13:35 -0500
            Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-22 22:29 +0200
              Re: Particle Physics Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2016-04-22 23:32 +0200
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-23 06:15 +0200
                Re: Particle Physics JanPB <filmart@gmail.com> - 2016-04-22 22:25 -0700
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-23 23:18 +0200
                Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-24 13:55 -0500
              Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-23 08:33 -0500
                Re: Particle Physics Dirk Van de moortel <dirkvandemoortel@hotspam.not> - 2016-04-23 15:53 +0200
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-23 20:36 +0200
                Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-24 13:59 -0500
              Re: Particle Physics Tom Roberts <tjroberts137@sbcglobal.net> - 2016-04-23 16:43 -0500
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-24 07:16 +0200
                Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-24 14:02 -0500
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-25 06:55 +0200
                Re: Particle Physics Odd Bodkin <bodkinodd@gmail.com> - 2016-04-25 06:07 -0500
                Re: Particle Physics Thomas Heger <ttt_heg@web.de> - 2016-04-26 22:24 +0200

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