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Re: Is Space different in QM and GR

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Am 14.08.2018 um 02:30 schrieb Tom Roberts:
> On 8/13/18 1:38 PM, Thomas Heger wrote:
>> What we call 'universe' or 'space' matches the description of our own 
>> past light cone (in GR lingo).
> 
> Not at all! The past lightcone of any given event is a 4-D spacetime 
> region -- nowhere close to what we mean by "space" or "universe".
> 
>      Some authors define "past lightcone" as the locus from
>      which light rays will directly reach the given event.
>      Others include the interior of that locus, as do I.
> 
> Moreover, there are events outside of our past lightcone that CLEARLY 
> belong to space, and to the universe. For instance, at a given time both 
> the earth and the sun exist in space, but are outside each other's past 
> lightcone.


'Past light cone' is not really a cone. In a 3d Minkowski diagram we 
have one spatial dimension missing. So we need to take two dimensions as 
representative for three.

The picture means: nested spheres, the further away the longer ago.

And if you think about it for a moment, than this is actually what we 
find in the sky.

So: what we call 'universe' is not universal at all, but the picture we 
receive from the past and along the light cone.

That is not space, sure. But it is, what we actually see, if we look 
through a telescope.

The 'real thing' must therefor be assumed, so that it would look like 
our sky under the mentioned conditions.

IOW: the real universe is invisible and has not the properties we 
ascribe to space.

I personally think, that Minkowski was in fact right with his proposal.

>> So it's more like Hermann Minkowski said, that there are a multitude 
>> of spaces, not just a single one.
> 
> He said that, because to define "space" in SR/GR one must project 
> spacetime onto an achronal 3-d surface [#]. In SR the usual way to do 
> that is to select an inertial frame and consider the 3-d submanifold 
> consisting of all points with a given value of its time coordinate. 
> Since there are an infinite number of inertial frames, there are an 
> infinite number of such submanifolds, each of which can be called "space".

I personally think, that Minkowski was in fact right with his proposal.

>      [#] A surface for which the interval between every
>      pair of events is spacelike.
> 
>> [... considerable nonsense omitted]



So, what is your motivation for spreading nonsense for decades over the 
UseNet.

Is that a job? Or is this a cult?


TH

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Is Space different in QM and GR SolomonW <SoloomonW@citi.com.au> - 2018-08-13 13:58 +1000
  Re: Is Space different in QM and GR Gary Harnagel <hitlong@yahoo.com> - 2018-08-12 21:11 -0700
    Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-13 12:23 -0700
  Re: Is Space different in QM and GR The Starmaker <starmaker@ix.netcom.com> - 2018-08-12 22:08 -0700
  Re:Is Space different in QM and GR Libor Striz <poutnik4REMOVEnntp@CAPITALSgmail.com> - 2018-08-13 07:17 +0200
  Re: Is Space different in QM and GR Tom Roberts <tjroberts137@sbcglobal.net> - 2018-08-13 10:21 -0500
    Re: Is Space different in QM and GR Lovu Biftek <ufeli@fupuks.cl> - 2018-08-13 15:59 +0000
      Re: Is Space different in QM and GR Tom Roberts <tjroberts137@sbcglobal.net> - 2018-08-13 11:58 -0500
        Re: Is Space different in QM and GR Lovu Biftek <ufeli@fupuks.cl> - 2018-08-13 21:26 +0000
    Re: Is Space different in QM and GR Thomas Heger <ttt_heg@web.de> - 2018-08-13 20:38 +0200
      Re: Is Space different in QM and GR "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2018-08-13 12:37 -0700
        Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-13 12:49 -0700
          Re: Is Space different in QM and GR "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2018-08-13 13:09 -0700
            Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-13 13:28 -0700
              Re: Is Space different in QM and GR "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2018-08-13 14:10 -0700
      Re: Is Space different in QM and GR Tom Roberts <tjroberts137@sbcglobal.net> - 2018-08-13 19:30 -0500
        Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-13 18:09 -0700
          Re: Is Space different in QM and GR Lovu Biftek <ufeli@fupuks.cl> - 2018-08-14 10:17 +0000
        Re: Is Space different in QM and GR Thomas Heger <ttt_heg@web.de> - 2018-08-14 13:33 +0200
  Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-13 12:30 -0700
  Re: Is Space different in QM and GR kenseto <setoken@att.net> - 2018-08-14 07:53 -0700
    Re: Is Space different in QM and GR Lovu Biftek <ufeli@fupuks.cl> - 2018-08-14 20:38 +0000
      Re: Is Space different in QM and GR kenseto <setoken@att.net> - 2018-08-14 14:51 -0700
        Re: Is Space different in QM and GR Lovu Biftek <ufeli@fupuks.cl> - 2018-08-14 22:44 +0000
          Re: Is Space different in QM and GR mitchrae3323@gmail.com - 2018-08-14 15:53 -0700

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