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Re: Is Space different in QM and GR

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Am 13.08.2018 um 17:21 schrieb Tom Roberts:
> On 8/12/18 10:58 PM, SolomonW wrote:
>> is space something different in QM compared to GR?
> 
> Remember that both QM and GR are models of the world we inhabit, but 
> they are valid in different domains. The overlap of their respective 
> domains is essentially empty.
> 
> Both models use 3-d spatial manifolds to model space. In GR that is not 
> fundamental, but is a projection of a (3+1)-dimensional spacetime 
> manifold. In QM, space is flat (i.e. its Riemann curvature tensor is 
> identically zero); not so in GR, where the curvature of spacetime (and 
> thus of space) is of fundamental importance.
> 
>      Note that on cosmological scales, space is observed to be flat
>      (within measurement resolution); on smaller scales it is not.
> 

What we call 'universe' or 'space' matches the description of our own 
past light cone (in GR lingo).

So it's more like Hermann Minkowski said, that there are a multitude of 
spaces, not just a single one.

The 'realm of overlap' would then be simply a point, which we could call 
'observer'.

The observer is somewhere and in his direct vicinity there are those 
tiny particles, that QM deals with, while on a larger scale and further 
distance we see remote objects like stars.

These stars belong to the realm visible to us (as observers), hence are 
'relative' (as is space).

The 'real thing', however', must be something (like spacetime), which 
looks in close proximity like particles and on the large scale like 
stars in distance.

This is so because nature must be understood as undivided and more or 
less independent from some special observer.

So the world of particles and the realm of QM is a certain perspective 
we have in our vicinity from the 'real thing', that behave differently 
than QM thinks.

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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