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Re: Why is space three-dimensional? ... Thermodynamics

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john wrote:

> You can go somewhere anytime you want.

Superficially, it would be nice if it were true, but if you think this 
through you realize that if this were possible then it would break 
causality.

Which locations you can reach from where you are at which point in time is 
obviously limited not only by the directions in which you can go, but also 
by the speeds that you can achieve.  So conceivable spatial obstacles aside, 
as far as we know, the maximum possible speed is the constant, finite speed 
of light in vacuum.

And so it makes sense to consider not only space, but space(-)time where a 
position is an *event*, each of which has (3) spatial coordinates and a (1) 
temporal coordinate.

There are two *light cones* originating from (having their tip at) the 
observer’s position in spacetime (which for simplicity we can define as the 
origin of the coordinate system) that extend into the past, the future and 
in space: you can learn from events that lie on and inside the past light 
cone, you can affect and reach events that lie within the future light cone, 
and you can send (light) signals to arrive at events that lie on the future 
light cone.  (Everything that lies on a light cone travels at the speed of 
light, everything inside travels slower; everything outside would have to 
travel faster than light, which is not possible.)

<http://www.britannica.com/topic/Albert-Einstein-on-Space-Time-1987141>
<https://en.wikipedia.org/wiki/Light_cone>

> Doesn't change the "where".
> No zero volume entities.
> No point particles.

Wishful thinking; *observation* tells us otherwise.

> No 2D.
> No 1D.
> Just 3D.
> Physical.

Time is an essential part of the physical world, so only three (spatial) 
dimensions do not suffice to describe it.

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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Why is space three-dimensional? ... Thermodynamics Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-05-04 04:08 -0400
  Why is space three-dimensional? ... Thermodynamics john <johnsefton288@gmail.com> - 2016-05-04 04:43 -0700
    Why is space three-dimensional? ... Thermodynamics HVAC <mr.hvac@gmail.com> - 2016-05-04 04:49 -0700
      Why is space three-dimensional? ... Thermodynamics john <johnsefton288@gmail.com> - 2016-05-04 05:29 -0700
        Why is space three-dimensional? ... Thermodynamics HVAC <mr.hvac@gmail.com> - 2016-05-04 05:35 -0700
        Re: Why is space three-dimensional? ... Thermodynamics Odd Bodkin <bodkinodd@gmail.com> - 2016-05-04 12:24 -0500
          Re: Why is space three-dimensional? ... Thermodynamics john <johnsefton288@gmail.com> - 2016-05-04 10:31 -0700
            Re: Why is space three-dimensional? ... Thermodynamics Odd Bodkin <bodkinodd@gmail.com> - 2016-05-04 16:57 -0500
              Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-04 15:12 -0700
                Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-04 21:49 -0400
                Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-05 05:37 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Odd Bodkin <bodkinodd@gmail.com> - 2016-05-05 10:58 -0500
                Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-05 13:50 -0700
            Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-05 05:51 +0200
              Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-05 04:45 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Odd Bodkin <bodkinodd@gmail.com> - 2016-05-05 11:29 -0500
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-06 05:36 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Odd Bodkin <bodkinodd@gmail.com> - 2016-05-06 09:40 -0500
                Re: Why is space three-dimensional? ... Thermodynamics john <johnsefton288@gmail.com> - 2016-05-06 08:00 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-06 19:54 +0200
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-07 00:36 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Sam Wormley <swormley1@gmail.com> - 2016-05-07 09:28 -0500
                Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-07 07:53 -0700
                Re: Why is space three-dimensional? ... Thermodynamics HVAC <mr.hvac@gmail.com> - 2016-05-07 08:08 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-07 12:59 -0700
                Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-08 00:21 -0400
                Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-07 23:50 -0400
                Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-08 00:01 -0400
                Re: Why is space three-dimensional? ... Thermodynamics Mahipal <mahipal7638@gmail.com> - 2016-05-08 08:17 -0700
                Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-09 00:48 -0400
                Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-07 17:13 +0200
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-08 00:56 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-08 10:04 +0200
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-08 05:19 -0700
                Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-08 14:58 +0200
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-09 00:00 -0700
                Re: Why is space three-dimensional? ... Thermodynamics jay moseley <jaymoseley@hotmail.com> - 2016-05-09 00:35 -0700
                Re: Why is space three-dimensional? ... Thermodynamics "Y.Porat" <y.y.porat@gmail.com> - 2016-05-08 22:19 -0700
                Re: Why is space three-dimensional? ... Thermodynamics "Y.Porat" <y.y.porat@gmail.com> - 2016-05-06 22:55 -0700
                Re: Why is space three-dimensional? ... Thermodynamics A Nony Mouse <abc@cef.ghi> - 2016-05-07 00:02 -0600
                Re: Why is space three-dimensional? ... Thermodynamics Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-05-07 17:59 +0200
          Re: Why is space three-dimensional? ... Thermodynamics "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-05-05 14:51 -0700
            Re: Why is space three-dimensional? ... Thermodynamics Sam Wormley <swormley1@gmail.com> - 2016-05-05 16:57 -0500
  Re: Why is space three-dimensional? ... Thermodynamics Parag Mishra <parag.misra2009@gmail.com> - 2016-05-04 08:14 -0700
    Re: Why is space three-dimensional? ... Thermodynamics Sam Wormley <swormley1@gmail.com> - 2016-05-04 11:17 -0500
  Re: Why is space three-dimensional? ... Thermodynamics "Y.Porat" <y.y.porat@gmail.com> - 2016-05-05 01:37 -0700
  Re: Why is space three-dimensional? ... Thermodynamics "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-05-05 09:27 -0700
    Re: Why is space three-dimensional? ... Thermodynamics "hanson" <hanson@quick.net> - 2016-05-05 10:47 -0700
    Re: Why is space three-dimensional? ... Thermodynamics Sam Wormley <swormley1@gmail.com> - 2016-05-05 15:26 -0500
      Re: Why is space three-dimensional? ... Thermodynamics "nuny@bid.nes" <Alien8752@gmail.com> - 2016-05-05 14:43 -0700
        Re: Why is space three-dimensional? ... Thermodynamics "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2016-05-05 15:03 -0700
          Re: Why is space three-dimensional? ... Thermodynamics "reber g=emc^2" <herbertglazier0@gmail.com> - 2016-05-06 10:12 -0700
        Re: Why is space three-dimensional? ... Thermodynamics ClutterFreak <ClutterFreak@FakeAddress.com> - 2016-05-05 18:47 -0500
          Re: Why is space three-dimensional? ... Thermodynamics "hanson" <hanson@quick.net> - 2016-05-05 21:09 -0700
        Re: Why is space three-dimensional? ... Thermodynamics benj <nobodyxx@gmail> - 2016-05-05 22:16 -0400
  Re: Why is space three-dimensional? ... Thermodynamics "nuny@bid.nes" <Alien8752@gmail.com> - 2016-05-05 15:25 -0700
    Re: Why is space three-dimensional? ... Thermodynamics john <johnsefton288@gmail.com> - 2016-05-05 16:26 -0700
    Re: Why is space three-dimensional? ... Thermodynamics Yousuf Khan <bbbl67@spammenot.yahoo.com> - 2016-05-08 00:04 -0400

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