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Re: What modern physics is really about, from a woodworker's view

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On 8/26/17 3:01 PM, dancouriann@gmail.com wrote:
> On Friday, August 25, 2017 at 3:28:25 PM UTC-7, Odd Bodkin wrote:
>> All "things" have been replaced by fields which extend over
>> ALL space and time. They don't live IN space and time... they
>> are part of the fabric OF space and time... the idea of "things"
>> moving through space and time has become replaced with the idea
>> of fields that extend everywhere...
> 
> Be careful not to mix up the concept of "localized objects" with the concept of background independence.  Standard quantum field theory is firmly based on fields that exist IN a fixed background of space and time. The fields of the standard model are not part of the "fabric" OF space and time.  Their extension is a separate issue, but note that energy is localizable in standard QFT.  General relativity, at least in the weak field limit in asymptotically flat space-time, can also be interpreted as a quantum field theory IN a fixed space and time, but in general the full non-linear field equations have a geometrical interpretation in which the metrical field is indeed part OF the "fabric" of space-time, and gravitational energy is not localizable.
> 
>> (I've glossed over a key idea that a field is nothing more than
>> a map of the value(s) of a property(ies) OF spacetime itself...
> 
> I'm not sure how to interpret that.  The fields of the standard model and standard quantum field theory exist in a fixed flat Minkowski space-time.  Attempts to develop a theory with the "key idea" that you described were tried, but they failed, basically because there is no "equivalence principle" for the other forces of nature, that would enable them to be interpreted as features of the geometrical structure of spacetime.
> 

Not what I meant. I'm not referring to a geometric structure a la Kaluza 
and Klein. There is also a fair amount of work that has been done with 
quantum field theory in a curved, dynamic spacetime, so I'm not sure 
it's fair to say that QFTs *only* have been worked out in static flat 
spacetime.

As for whether the fields are separate in existence from the background, 
this is precisely the shift that I'm starting to see in what I'm reading 
-- that there is no reason to think that fields are a thing IN 
spacetime. That is, if you consider that a field is essentially defined 
as a map of some properties over space and time, then the question is, 
properties of WHAT? The field is a map of the properties of the field 
itself? This is where the metric serves as a leading example, not as a 
pointer to a geometric interpretation of the properties, but merely that 
the metric is a description of some properties of spacetime ITSELF, and 
so other fields may indeed be other properties (nongeometric ones, 
perhaps) of spacetime.

-- 
Odd Bodkin -- maker of fine toys, tools, tables

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What modern physics is really about, from a woodworker's view Odd Bodkin <bodkinodd@gmail.com> - 2017-08-25 17:28 -0500
  Re: What modern physics is really about, from a woodworker's view numbernumber1964@gmail.com - 2017-08-25 15:42 -0700
  Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-25 19:17 -0500
    Re: What modern physics is really about, from a woodworker's view benj <nobody@yahoo.com> - 2017-08-26 01:50 -0400
      Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-26 09:07 -0500
        Re: What modern physics is really about, from a woodworker's view Gary Harnagel <hitlong@yahoo.com> - 2017-08-26 08:03 -0700
        Re: What modern physics is really about, from a woodworker's view Odd Bodkin <bodkinodd@gmail.com> - 2017-08-26 10:43 -0500
          Re: What modern physics is really about, from a woodworker's view mlwozniak@wp.pl - 2017-08-26 09:13 -0700
          Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-26 11:26 -0500
            Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-26 17:43 -0400
              Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-27 11:41 -0500
                Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-28 16:23 -0400
          Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-26 17:35 -0400
        Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-26 17:31 -0400
          Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-26 17:01 -0500
            Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-26 18:53 -0400
              Re: What modern physics is really about, from a woodworker's view Serg io <invalid@invalid.com> - 2017-08-27 10:20 -0500
                Re: What modern physics is really about, from a woodworker's view benj <benj@nobody.net> - 2017-08-28 16:21 -0400
          Re: What modern physics is really about, from a woodworker's view mlwozniak@wp.pl - 2017-08-26 22:52 -0700
  Re: What modern physics is really about, from a woodworker's view mlwozniak@wp.pl - 2017-08-25 23:51 -0700
  Re: What modern physics is really about, from a woodworker's view Bídníkùm Laterá <bila@wehia.ui> - 2017-08-26 12:00 +0000
  Re: What modern physics is really about, from a woodworker's view moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-08-26 16:19 +0000
    Re: What modern physics is really about, from a woodworker's view Odd Bodkin <bodkinodd@gmail.com> - 2017-08-26 14:25 -0500
      Re: What modern physics is really about, from a woodworker's view mlwozniak@wp.pl - 2017-08-26 13:38 -0700
  Re: What modern physics is really about, from a woodworker's view dancouriann@gmail.com - 2017-08-26 13:01 -0700
    Re: What modern physics is really about, from a woodworker's view Odd Bodkin <bodkinodd@gmail.com> - 2017-08-26 15:23 -0500
      Re: What modern physics is really about, from a woodworker's view dancouriann@gmail.com - 2017-08-27 00:00 -0700
        Re: What modern physics is really about, from a woodworker's view Odd Bodkin <bodkinodd@gmail.com> - 2017-08-27 16:59 -0500
          Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-28 10:55 -0700
            Re: What modern physics is really about, from a woodworker's view Gary Harnagel <hitlong@yahoo.com> - 2017-08-28 11:09 -0700
      Re: What modern physics is really about, from a woodworker's view Prokaryotic Caspase Homolog <prokaryotic.caspase.homolog@gmail.com> - 2017-08-27 01:33 -0700
  Re: What modern physics is really about, from a woodworker's view numbernumber1964@gmail.com - 2017-08-26 14:43 -0700
  Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-26 15:57 -0700
    Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-26 17:08 -0700
      Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-26 18:00 -0700
        Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-26 19:15 -0700
  Re: What modern physics is really about, from a woodworker's view Thomas Heger <ttt_heg@web.de> - 2017-08-28 21:11 +0200
    Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-28 12:22 -0700
      Re: What modern physics is really about, from a woodworker's view Thomas Heger <ttt_heg@web.de> - 2017-08-28 21:49 +0200
        Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-28 23:43 -0700
          Re: What modern physics is really about, from a woodworker's view Thomas Heger <ttt_heg@web.de> - 2017-08-29 16:01 +0200
            Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-29 10:42 -0700
              Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-30 09:37 -0700
                Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-08-30 10:06 -0700
                Re: What modern physics is really about, from a woodworker's view Thomas Heger <ttt_heg@web.de> - 2017-08-30 21:45 +0200
          Re: What modern physics is really about, from a woodworker's view The Starmaker <starmaker@ix.netcom.com> - 2017-09-02 12:46 -0700
            Re: What modern physics is really about, from a woodworker's view Thomas Heger <ttt_heg@web.de> - 2017-09-03 22:32 +0200

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