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NNTP-Posting-Date: Sun, 08 May 2016 08:03:47 -0500
Subject: Re: Where did the 3 geometric dimensions come from?
Newsgroups: sci.physics
References: <dp8natFrm3hU1@mid.individual.net>
From: Sam Wormley <swormley1@gmail.com>
Date: Sun, 8 May 2016 08:03:47 -0500
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On 5/8/16 6:47 AM, 7 wrote:
> Where did the 3 geometric dimensions come from?

   One might say that the three spatial dimensions where created in the
   big bang... and that of course begs the question, where there three
   spatial dimensions in the environment in which the big bang occurred.


   Here is a reason there are only four dimensions in our universe.
   Tegmark: On the dimensionality of spacetime
 > http://space.mit.edu/home/tegmark/dimensions.pdf

 > Abstract.

 > Some superstring theories have more than one effective low-energy
 > limit corresponding to classical spacetimes with different
 > dimensionalities. We argue that all but the (3 + 1)-dimensional one
 > might correspond to ‘dead worlds’, devoid of observers, in which case
 > all such ensemble theories would actually predict that we should find
 > ourselves inhabiting a (3 + 1)-dimensional spacetime. With more or
 > less than one time dimension, the partial differential equations of
 > nature would lack the hyperbolicity property that enables observers
 > to make predictions. In a space with more than three dimensions,
 > there can be no traditional atoms and perhaps no stable structures. A
 > space with less than three dimensions allows no gravitational force
 > and may be too simple and barren to contain observers.

-- 

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