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Groups > sci.physics.relativity > #406996 > unrolled thread

Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT?

Started by"HGW, DSc." <HG@....>
First post2017-01-28 06:58 +1100
Last post2017-02-01 12:18 -0800
Articles 20 on this page of 79 — 18 participants

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Contents

  Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-28 06:58 +1100
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Juliana Auerbach <jaot@tognaenn.org> - 2017-01-27 20:15 +0000
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Odd Bodkin <bodkinodd@gmail.com> - 2017-01-27 14:20 -0600
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Juliana Auerbach <jaot@tognaenn.org> - 2017-01-27 20:30 +0000
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-02-02 02:17 +0100
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Irvin Starrett <etrrarn@arneir.etr> - 2017-02-02 05:03 +0000
            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-02-02 12:37 +0100
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? moroney@world.std.spaamtrap.com (Michael Moroney) - 2017-01-28 00:48 +0000
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-29 09:44 +1100
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Y <yanarchi@hotmail.com> - 2017-02-01 15:03 -0800
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-27 14:33 -0600
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-29 10:04 +1100
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "Paul B. Andersen" <relativity@paulba.no> - 2017-01-29 10:31 +0100
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-30 06:46 +1100
            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "Paul B. Andersen" <relativity@paulba.no> - 2017-01-29 21:55 +0100
              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-30 20:40 +1100
                Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "Paul B. Andersen" <relativity@paulba.no> - 2017-01-30 21:20 +0100
                  Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-31 20:05 +1100
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Juanita Forney <iatiet@oetnnrn.org> - 2017-01-31 10:54 +0000
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-01 09:40 +1100
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-31 10:20 -0800
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-01 09:27 +1100
                        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-31 15:45 -0800
                          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-01 11:04 -0800
                            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-01 11:12 -0800
                              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-01 16:47 -0800
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-31 19:42 -0600
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-02 06:58 +1100
                        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-01 14:42 -0800
                          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-02 10:53 -0800
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? mlwozniak@wp.pl - 2017-02-01 14:00 -0800
            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? benj <benj@nobody.net> - 2017-01-30 17:50 -0500
              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? xxein1@att.net - 2017-01-30 17:39 -0800
              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-31 20:08 +1100
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-30 09:06 -0600
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-31 20:12 +1100
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-01-28 12:04 +1100
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? mlwozniak@wp.pl - 2017-01-28 03:03 -0800
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-01-29 13:26 +1100
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? mlwozniak@wp.pl - 2017-01-29 11:40 -0800
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-28 18:21 -0800
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-01-29 13:27 +1100
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-29 00:45 -0800
            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-29 11:52 -0800
              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-29 12:51 -0800
                Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-29 14:36 -0800
                  Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-29 18:04 -0800
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-30 23:42 -0800
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-01-31 20:10 +1100
                        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-01-31 10:17 -0800
                          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-01 09:43 +1100
                          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-02-02 22:44 +1100
                            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-02 09:37 -0800
                            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-03 08:24 -0800
                              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-03 16:59 -0800
                                Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-02-04 12:08 +1100
                                  Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? benj <benj@nobody.net> - 2017-02-03 20:18 -0500
                                  Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-03 21:39 -0800
                                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? The Starmaker <starmaker@ix.netcom.com> - 2017-02-04 12:37 -0800
                                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? alsor@interia.pl - 2017-02-04 14:32 -0800
                                Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? benj <benj@nobody.net> - 2017-02-03 20:23 -0500
                              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-02-04 12:06 +1100
          Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-29 19:50 +1100
            Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Sylvia Else <sylvia@not.at.this.address> - 2017-01-29 19:59 +1100
              Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-30 06:50 +1100
                Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-30 09:25 -0600
                  Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-01-31 20:19 +1100
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Juanita Forney <iatiet@oetnnrn.org> - 2017-01-31 10:59 +0000
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-31 10:49 -0600
                    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? Tom Roberts <tjroberts137@sbcglobal.net> - 2017-01-31 10:44 -0600
                      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-01 10:10 +1100
    Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-01-30 19:03 -0800
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? alsor@interia.pl - 2017-01-31 10:43 -0800
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-01 10:12 +1100
        Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? alsor@interia.pl - 2017-02-01 11:46 -0800
    Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? JanPB <filmart@gmail.com> - 2017-01-31 15:20 -0800
      Re: Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "HGW, DSc." <HG@....> - 2017-02-02 07:00 +1100
    Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-02-01 12:13 -0800
      Let's Get This Straight. Is Free Falling 'Inertial' or Is it NOT? "David (Lord Kronos Prime) Fuller" <fuller.david@hotmail.com> - 2017-02-01 12:18 -0800

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#407385

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-01-31 10:20 -0800
Message-ID<5890D567.61CC@ix.netcom.com>
In reply to#407322
HGW, DSc. wrote:
> 
> On 31/01/17 07:20, Paul B. Andersen wrote:
> > On 30.01.2017 10:40, HGW, DSc. wrote:
> >> On 30/01/17 07:55, Paul B. Andersen wrote:
> 
> >> I suspected this would be too hard for you. I was right.
> >>
> >> In an  x-t diagram, constant speed of an object is represented by a
> >> straight line. Nothing 'moves'. Acceleration causes the line to be
> >> curved. Again nothing moves.
> >
> > And since acceleration causes the x-t line to curve but not to move,
> > it is obvious that any movement represents Newtonian acceleration.
> >
> > Another crystal clear thought. :-D
> >
> >> Ask yourself, what is an object doing if its x-t LINE IS continually
> >> changing somehow?
> >
> > My parser returns the message "doesn't parse".
> >
> > Hanry, you are a master of nonsensical self contradictory statements,
> > and even if I find them quite funny at times, I have had enough for now.
> 
> Can't answer can you? I'll ask again. What does movement signify in
> space/time?


the only thing i know that moves in your space/time is tiny little
particles.

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#407428

From"HGW, DSc." <HG@....>
Date2017-02-01 09:27 +1100
Message-ID<o6r2uo$1ml5$2@gioia.aioe.org>
In reply to#407385
On 01/02/17 05:20, The Starmaker wrote:
> HGW, DSc. wrote:

>>>
>>> Hanry, you are a master of nonsensical self contradictory statements,
>>> and even if I find them quite funny at times, I have had enough for now.
>>
>> Can't answer can you? I'll ask again. What does movement signify in
>> space/time?
>
>
> the only thing i know that moves in your space/time is tiny little
> particles.

..and what does that actually mean?

[toc] | [prev] | [next] | [standalone]


#407444

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-01-31 15:45 -0800
Message-ID<5891218F.57DA@ix.netcom.com>
In reply to#407428
HGW, DSc. wrote:
> 
> On 01/02/17 05:20, The Starmaker wrote:
> > HGW, DSc. wrote:
> 
> >>>
> >>> Hanry, you are a master of nonsensical self contradictory statements,
> >>> and even if I find them quite funny at times, I have had enough for now.
> >>
> >> Can't answer can you? I'll ask again. What does movement signify in
> >> space/time?
> >
> >
> > the only thing i know that moves in your space/time is tiny little
> > particles.
> 
> ..and what does that actually mean?


you want an example? the earth, the planet earth...that thing you walk
on yous call a planet..is just a particle.

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#407505

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-02-01 11:04 -0800
Message-ID<58923125.526E@ix.netcom.com>
In reply to#407444
The Starmaker wrote:
> 
> HGW, DSc. wrote:
> >
> > On 01/02/17 05:20, The Starmaker wrote:
> > > HGW, DSc. wrote:
> >
> > >>>
> > >>> Hanry, you are a master of nonsensical self contradictory statements,
> > >>> and even if I find them quite funny at times, I have had enough for now.
> > >>
> > >> Can't answer can you? I'll ask again. What does movement signify in
> > >> space/time?
> > >
> > >
> > > the only thing i know that moves in your space/time is tiny little
> > > particles.
> >
> > ..and what does that actually mean?
> 
> you want an example? the earth, the planet earth...that thing you walk
> on yous call a planet..is just a particle.


carl sagan calls it...a blue dot.

[toc] | [prev] | [next] | [standalone]


#407507

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-02-01 11:12 -0800
Message-ID<58923334.7317@ix.netcom.com>
In reply to#407505
The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > HGW, DSc. wrote:
> > >
> > > On 01/02/17 05:20, The Starmaker wrote:
> > > > HGW, DSc. wrote:
> > >
> > > >>>
> > > >>> Hanry, you are a master of nonsensical self contradictory statements,
> > > >>> and even if I find them quite funny at times, I have had enough for now.
> > > >>
> > > >> Can't answer can you? I'll ask again. What does movement signify in
> > > >> space/time?
> > > >
> > > >
> > > > the only thing i know that moves in your space/time is tiny little
> > > > particles.
> > >
> > > ..and what does that actually mean?
> >
> > you want an example? the earth, the planet earth...that thing you walk
> > on yous call a planet..is just a particle.
> 
> carl sagan calls it...a blue dot.


Just imagine if you will..

somebody looking
through a 
very powerful
microscope...
at all these particles,
and suddendly sees..

a pale blue dot.


What does it mean? It means they have to get funding for a more powerful microscope.

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#407541

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-02-01 16:47 -0800
Message-ID<589281B8.44D2@ix.netcom.com>
In reply to#407507
The Starmaker wrote:
> 
> The Starmaker wrote:
> >
> > The Starmaker wrote:
> > >
> > > HGW, DSc. wrote:
> > > >
> > > > On 01/02/17 05:20, The Starmaker wrote:
> > > > > HGW, DSc. wrote:
> > > >
> > > > >>>
> > > > >>> Hanry, you are a master of nonsensical self contradictory statements,
> > > > >>> and even if I find them quite funny at times, I have had enough for now.
> > > > >>
> > > > >> Can't answer can you? I'll ask again. What does movement signify in
> > > > >> space/time?
> > > > >
> > > > >
> > > > > the only thing i know that moves in your space/time is tiny little
> > > > > particles.
> > > >
> > > > ..and what does that actually mean?
> > >
> > > you want an example? the earth, the planet earth...that thing you walk
> > > on yous call a planet..is just a particle.
> >
> > carl sagan calls it...a blue dot.
> 
> Just imagine if you will..
> 
> somebody looking
> through a
> very powerful
> microscope...
> at all these particles,
> and suddendly sees..
> 
> a pale blue dot.
> 


The problem with the 'scientific community' is that they don't understand
the blue dot.

One example, if you're looking for another earth, you'll discover that there only exist
only one planet in the entire universe that it's surface is blue like the planet earth.

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#407451

FromTom Roberts <tjroberts137@sbcglobal.net>
Date2017-01-31 19:42 -0600
Message-ID<BtGdnVKR05droQzFnZ2dnUU7_8zNnZ2d@giganews.com>
In reply to#407322
On 1/31/17 1/31/17   3:05 AM, HGW, DSc. wrote:
> What does movement signify in space/time?

You repeatedly display your complete IGNORANCE of what science actually is.

Physics in general, and spacetime in particular, are MODELS of the world we 
inhabit, or of interesting alternative worlds.

In the MODEL that is spacetime, a pointlike object IN THE MODELED WORLD is 
represented as a line (its "worldline"). In the MODELED WORLD it can move 
arbitrarily (within the constraints of its equations of motion), and variations 
in its motion correspond to bends in its worldline -- inertial pointlike objects 
have straight worldlines (in SR, geodesic worldlines in GR), while accelerated 
(non-inertial) pointlike objects have non-straight worldlines.

	So think about the earth orbiting the sun. In spacetime, using
	coordinates in which the sun is at rest, its worldline is a
	helix with radius 1 a.u. and period 1 year; its axis is
	parallel to the time coordinate. Such a model requires GR,
	in which this helix is a geodesic path through spacetime.

	(I am omitting some caveats and conditions for clarity.)

In the MODEL those lines are eternal and unchanging (because after all, what is 
happening in the world is determined by the equations of motion of all its 
constituents). To THE ANALYST, the entire 4-d spacetime MODEL is available for 
inspection at any time (i.e. ANALYST'S TIME), and TO THE ANALYST nothing is 
moving IN THE MODEL. But IN THE WORLD BEING MODELED anything can move within the 
constraints of its equations of motion.

BTW This is no different from Newtonian mechanics -- that is a different model, 
but the analyst can examine any and all times and locations in the model.

So we see that HGW's confusion is due to his poor phrasing, imprecise language, 
and reliance on PUNS -- "movement" has different meanings (in the world or in 
the model; relative to other objects in the world being modeled, or relative to 
the analyst).

Tom Roberts

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#407513

From"HGW, DSc." <HG@....>
Date2017-02-02 06:58 +1100
Message-ID<o6tej3$1bop$1@gioia.aioe.org>
In reply to#407451
On 01/02/17 12:42, Tom Roberts wrote:
> On 1/31/17 1/31/17   3:05 AM, HGW, DSc. wrote:
>> What does movement signify in space/time?
>
> You repeatedly display your complete IGNORANCE of what science
> actually is.
>
> Physics in general, and spacetime in particular, are MODELS of the
> world we inhabit, or of interesting alternative worlds.
>
> In the MODEL that is spacetime, a pointlike object IN THE MODELED
> WORLD is represented as a line (its "worldline"). In the MODELED
> WORLD it can move arbitrarily (within the constraints of its
> equations of motion), and variations in its motion correspond to
> bends in its worldline -- inertial pointlike objects have straight
> worldlines (in SR, geodesic worldlines in GR), while accelerated
> (non-inertial) pointlike objects have non-straight worldlines.

Thank you for repeating what I just told you. I hope you are not trying
to take credit for it.
....but you still have not gotten the idea that Einstein's spacetime is
bullshit and Galilean is perfectly legitimate.

> So think about the earth orbiting the sun. In spacetime, using
> coordinates in which the sun is at rest, its worldline is a helix
> with radius 1 a.u. and period 1 year; its axis is parallel to the
> time coordinate. Such a model requires GR, in which this helix is a
> geodesic path through spacetime.

See! You don't know Galilean space/time does exactly the same.
It does NOT need GR.

> (I am omitting some caveats and conditions for clarity.)
>
> In the MODEL those lines are eternal and unchanging (because after
> all, what is happening in the world is determined by the equations of
> motion of all its constituents). To THE ANALYST, the entire 4-d
> spacetime MODEL is available for inspection at any time (i.e.
> ANALYST'S TIME), and TO THE ANALYST nothing is moving IN THE MODEL.
> But IN THE WORLD BEING MODELED anything can move within the
> constraints of its equations of motion.

yes we know all that....

> BTW This is no different from Newtonian mechanics -- that is a
> different model, but the analyst can examine any and all times and
> locations in the model.
>
> So we see that HGW's confusion is due to his poor phrasing,
> imprecise language, and reliance on PUNS -- "movement" has different
> meanings (in the world or in the model; relative to other objects in
> the world being modeled, or relative to the analyst).

My question to PA was, "what would a moving point or curve signify on a
space/time diagram?"

I assume you cannot answer that either.

> Tom Roberts

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#407531

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-02-01 14:42 -0800
Message-ID<58926464.4F98@ix.netcom.com>
In reply to#407513
HGW, DSc. wrote:
> 
> On 01/02/17 12:42, Tom Roberts wrote:
> > On 1/31/17 1/31/17   3:05 AM, HGW, DSc. wrote:
> >> What does movement signify in space/time?
> >
> > You repeatedly display your complete IGNORANCE of what science
> > actually is.
> >
> > Physics in general, and spacetime in particular, are MODELS of the
> > world we inhabit, or of interesting alternative worlds.
> >
> > In the MODEL that is spacetime, a pointlike object IN THE MODELED
> > WORLD is represented as a line (its "worldline"). In the MODELED
> > WORLD it can move arbitrarily (within the constraints of its
> > equations of motion), and variations in its motion correspond to
> > bends in its worldline -- inertial pointlike objects have straight
> > worldlines (in SR, geodesic worldlines in GR), while accelerated
> > (non-inertial) pointlike objects have non-straight worldlines.
> 
> Thank you for repeating what I just told you. I hope you are not trying
> to take credit for it.
> ....but you still have not gotten the idea that Einstein's spacetime is
> bullshit and Galilean is perfectly legitimate.


maybe you don't understand what spacetime means...


i can explain it to you clearly..


spacetime is the samething as e=mc2,

in otherwords


energy is mass and mass is energy


space is time and time is space.

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#407620

FromThe Starmaker <starmaker@ix.netcom.com>
Date2017-02-02 10:53 -0800
Message-ID<58938022.1A57@ix.netcom.com>
In reply to#407531
The Starmaker wrote:
> 
> HGW, DSc. wrote:
> >
> > On 01/02/17 12:42, Tom Roberts wrote:
> > > On 1/31/17 1/31/17   3:05 AM, HGW, DSc. wrote:
> > >> What does movement signify in space/time?
> > >
> > > You repeatedly display your complete IGNORANCE of what science
> > > actually is.
> > >
> > > Physics in general, and spacetime in particular, are MODELS of the
> > > world we inhabit, or of interesting alternative worlds.
> > >
> > > In the MODEL that is spacetime, a pointlike object IN THE MODELED
> > > WORLD is represented as a line (its "worldline"). In the MODELED
> > > WORLD it can move arbitrarily (within the constraints of its
> > > equations of motion), and variations in its motion correspond to
> > > bends in its worldline -- inertial pointlike objects have straight
> > > worldlines (in SR, geodesic worldlines in GR), while accelerated
> > > (non-inertial) pointlike objects have non-straight worldlines.
> >
> > Thank you for repeating what I just told you. I hope you are not trying
> > to take credit for it.
> > ....but you still have not gotten the idea that Einstein's spacetime is
> > bullshit and Galilean is perfectly legitimate.
> 
> maybe you don't understand what spacetime means...
> 
> i can explain it to you clearly..
> 
> spacetime is the samething as e=mc2,
> 
> in otherwords
> 
> energy is mass and mass is energy
> 
> space is time and time is space.

of course, if you don't like the word "spacetime", you can call it
something else...gravityland.

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#407530

Frommlwozniak@wp.pl
Date2017-02-01 14:00 -0800
Message-ID<cf57c028-7aef-4177-8ef5-07d3bf8785ec@googlegroups.com>
In reply to#407451
W dniu środa, 1 lutego 2017 02:42:20 UTC+1 użytkownik tjrob137 napisał:
> On 1/31/17 1/31/17   3:05 AM, HGW, DSc. wrote:
> > What does movement signify in space/time?
> 
> You repeatedly display your complete IGNORANCE of what science actually is.
> 
> Physics in general, and spacetime in particular, are MODELS of the world we 
> inhabit, 

Yes. they are models of your sick imagination - the only
world you know.

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#407285

Frombenj <benj@nobody.net>
Date2017-01-30 17:50 -0500
Message-ID<588fc31a$0$53041$c3e8da3$fdf4f6af@news.astraweb.com>
In reply to#407139
On 1/29/2017 2:46 PM, HGW, DSc. wrote:
> On 29/01/17 20:31, Paul B. Andersen wrote:
>> On 29.01.2017 00:04, HGW, DSc. wrote:
>>>
>>> 'AT rest' in Minkowski coordinates merely
>>> means constant velocity in Newtonian.
>>>
>>
>> :-D
>
> I am not at all surprised that you do not understand the significance of
> 'spacetime'. Since Newtonian 'velocity' is static in 4D space, it should
> be obvious that any 'movement' in 4D represents Newtonian acceleration.
>
> As the once regular poster here, Louis Savain, used to point out,
> "nothing MOVES' in spacetime.

Only if you assume spacetime to be a 4 dimensional manifold. Clearly 
since it "warps" such an assumption is incorrect.

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#407301

Fromxxein1@att.net
Date2017-01-30 17:39 -0800
Message-ID<28883107-21de-47d5-ab25-3c06a6fdd05d@googlegroups.com>
In reply to#407285
On Monday, January 30, 2017 at 5:50:05 PM UTC-5, benj wrote:
> On 1/29/2017 2:46 PM, HGW, DSc. wrote:
> > On 29/01/17 20:31, Paul B. Andersen wrote:
> >> On 29.01.2017 00:04, HGW, DSc. wrote:
> >>>
> >>> 'AT rest' in Minkowski coordinates merely
> >>> means constant velocity in Newtonian.
> >>>
> >>
> >> :-D
> >
> > I am not at all surprised that you do not understand the significance of
> > 'spacetime'. Since Newtonian 'velocity' is static in 4D space, it should
> > be obvious that any 'movement' in 4D represents Newtonian acceleration.
> >
> > As the once regular poster here, Louis Savain, used to point out,
> > "nothing MOVES' in spacetime.
> 
> Only if you assume spacetime to be a 4 dimensional manifold. Clearly 
> since it "warps" such an assumption is incorrect.

xxein:  Why?  What is spacetime then?  I want to know exactly what it is so that I may ponder it.

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#407323

From"HGW, DSc." <HG@....>
Date2017-01-31 20:08 +1100
Message-ID<o6pk5m$sm9$1@gioia.aioe.org>
In reply to#407285
On 31/01/17 09:50, benj wrote:
> On 1/29/2017 2:46 PM, HGW, DSc. wrote:
>> On 29/01/17 20:31, Paul B. Andersen wrote:
>>> On 29.01.2017 00:04, HGW, DSc. wrote:
>>>>
>>>> 'AT rest' in Minkowski coordinates merely
>>>> means constant velocity in Newtonian.
>>>>
>>>
>>> :-D
>>
>> I am not at all surprised that you do not understand the significance of
>> 'spacetime'. Since Newtonian 'velocity' is static in 4D space, it should
>> be obvious that any 'movement' in 4D represents Newtonian acceleration.
>>
>> As the once regular poster here, Louis Savain, used to point out,
>> "nothing MOVES' in spacetime.
>
> Only if you assume spacetime to be a 4 dimensional manifold. Clearly
> since it "warps" such an assumption is incorrect.

Well if you are so knowledgeable, you might like to help Paul Andersen 
explain what 'movement in spacetime' means.

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#407209

FromTom Roberts <tjroberts137@sbcglobal.net>
Date2017-01-30 09:06 -0600
Message-ID<mpmdnSIQB7QYyxLFnZ2dnUU7_83NnZ2d@giganews.com>
In reply to#407086
On 1/28/17 1/28/17 - 5:04 PM, HGW, DSc. wrote:
> 'AT rest' in Minkowski coordinates merely means constant
> velocity in Newtonian.

You merely display your PERSONAL IGNORANCE of what these terms actually mean.

> You haven't answered my question at all. How can an object thrown from the ISS
> towards the ground be considered inertial?

That's because you didn't bother to read what I wrote. I did answer it:

>> In General Relativity, a SMALL [#] free falling object is inertial in
>> the sense that its proper acceleration is identically zero.

Bottom line: when you insist on thinking in sound bites you have no hope
of understanding subtle concepts, such as modern physics. And when you
don't understand the subject and refuse to study it, you have even less
hope.

Tom Roberts

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#407325

From"HGW, DSc." <HG@....>
Date2017-01-31 20:12 +1100
Message-ID<o6pkcp$t3q$1@gioia.aioe.org>
In reply to#407209
On 31/01/17 02:06, Tom Roberts wrote:
> On 1/28/17 1/28/17 - 5:04 PM, HGW, DSc. wrote:
>> 'AT rest' in Minkowski coordinates merely means constant
>> velocity in Newtonian.
>
> You merely display your PERSONAL IGNORANCE of what these terms actually
> mean.
>
>> You haven't answered my question at all. How can an object thrown from
>> the ISS
>> towards the ground be considered inertial?
>
> That's because you didn't bother to read what I wrote. I did answer it:
>
>>> In General Relativity, a SMALL [#] free falling object is inertial in
>>> the sense that its proper acceleration is identically zero.
>
> Bottom line: when you insist on thinking in sound bites you have no hope
> of understanding subtle concepts, such as modern physics. And when you
> don't understand the subject and refuse to study it, you have even less
> hope.

Q) Readers, if it walks like a physicist, talks like a physicist, quacks 
like a physicist but thinks like a  duck, what is it?

A) Tom Roberts.

> Tom Roberts
>

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#407027

FromSylvia Else <sylvia@not.at.this.address>
Date2017-01-28 12:04 +1100
Message-ID<ef291iF9qj7U1@mid.individual.net>
In reply to#406996
On 28/01/2017 6:58 AM, HGW, DSc. wrote:
> To a person on the ground, an object falling to Earth is accelerating,
> as in dv/dt (ignore air). It also appears to be accelerating relative to
> Earth when viewed from the moon. ...yet it has been claimed here that
> the state of free fall is inertial.
> Note, all massive objects in the universe are freely 'falling' so can
> their 'reference frames' be regarded as inertial?

A person on the ground is not inertial, so the requirement that the laws 
of physics by the same for all inertial observers does not apply to the 
person on the ground. An inertial body accelerates in the frame of a 
non-inertial observer.

As for massive bodies being inertial, the problem is that, in common 
with all observers, the volume of space regarded as being inertial for 
the observer is that volume where the gravitational field doesn't vary 
significantly in either intensity or direction. A massive body itself 
creates a field that varies in intensity and direction, so the volume of 
space regarded as inertial is much smaller than the body.

Sylvia.

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#407047

Frommlwozniak@wp.pl
Date2017-01-28 03:03 -0800
Message-ID<f7bb8505-ea18-44b8-83b6-4eae1cab2ea9@googlegroups.com>
In reply to#407027
W dniu sobota, 28 stycznia 2017 02:04:51 UTC+1 użytkownik Sylvia Else napisał:

> A person on the ground is not inertial, so the requirement that the laws 
> of physics by the same for all inertial observers does not apply to the 
> person on the ground. An inertial body accelerates in the frame of a 
> non-inertial observer.

And, as every physicist is on the ground - they
never apply this rule.
Right, lady?

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#407094

FromSylvia Else <sylvia@not.at.this.address>
Date2017-01-29 13:26 +1100
Message-ID<ef5263Fqm0eU1@mid.individual.net>
In reply to#407047
On 28/01/2017 10:03 PM, mlwozniak@wp.pl wrote:
> W dniu sobota, 28 stycznia 2017 02:04:51 UTC+1 użytkownik Sylvia Else napisał:
>
>> A person on the ground is not inertial, so the requirement that the laws
>> of physics by the same for all inertial observers does not apply to the
>> person on the ground. An inertial body accelerates in the frame of a
>> non-inertial observer.
>
> And, as every physicist is on the ground - they
> never apply this rule.
> Right, lady?
>

Wrong. Where theory indicates that the fact that we're non-inertial in 
the vertical direction, that is taken into account. A physicist who 
mistakenly neglects the issue will find that their experiments don't 
produce the expected results, which will prod them to consider what 
they'd overlooked.

Sylvia.

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#407138

Frommlwozniak@wp.pl
Date2017-01-29 11:40 -0800
Message-ID<87090d48-c39d-45f1-a450-4053e0a26b00@googlegroups.com>
In reply to#407094
W dniu niedziela, 29 stycznia 2017 03:26:13 UTC+1 użytkownik Sylvia Else napisał:
> On 28/01/2017 10:03 PM, mlwozniak@wp.pl wrote:
> > W dniu sobota, 28 stycznia 2017 02:04:51 UTC+1 użytkownik Sylvia Else napisał:
> >
> >> A person on the ground is not inertial, so the requirement that the laws
> >> of physics by the same for all inertial observers does not apply to the
> >> person on the ground. An inertial body accelerates in the frame of a
> >> non-inertial observer.
> >
> > And, as every physicist is on the ground - they
> > never apply this rule.
> > Right, lady?
> >
> 
> Wrong. Where theory indicates that the fact that we're non-inertial in 
> the vertical direction, that is taken into account. A physicist who 
> mistakenly neglects the issue will find that their experiments don't 
> produce the expected results

In other words, lady, what You wrote 2 paragraphes above
is naive, worthless and has nothing in common with reality.

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