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Why is space three-dimensional?
Phys.org ^ | 3 May, 2016 | Lisa Zyga

Posted on 05/05/2016 6:53:04 PM PDT by MtnClimber

The question of why space is three-dimensional (3D) and not some other number of dimensions has puzzled philosophers and scientists since ancient Greece. Space-time overall is four-dimensional, or (3 + 1)-dimensional, where time is the fourth dimension. It's well-known that the time dimension is related to the second law of thermodynamics: time has one direction (forward) because entropy (a measure of disorder) never decreases in a closed system such as the universe.

In a new paper published in EPL, researchers have proposed that the second law of thermodynamics may also explain why space is 3D.

"A number of researchers in the fields of science and philosophy have addressed the problem of the (3+1)-dimensional nature of space-time by justifying the suitable choice of its dimensionality in order to maintain life, stability and complexity," coauthor Julian Gonzalez-Ayala, at the National Polytechnic Institute in Mexico and the University of Salamanca in Spain, told Phys.org.

..... The scientists propose that space is 3D because of a thermodynamic quantity called the Helmholtz free energy density. In a universe filled with radiation, this density can be thought of as a kind of pressure on all of space, which depends on the universe's temperature and its number of spatial dimensions.

Here the researchers showed that, as the universe began cooling from the moment after the big bang, the Helmholtz density reached its first maximum value at a very high temperature corresponding to when the universe was just a fraction of a second old, and when the number of spatial dimensions was approximately three. The key idea is that 3D space was "frozen in" at this point when the Helmholtz density reached its first maximum value, prohibiting 3D space from transitioning to other dimensions.

(Excerpt) Read more at phys.org ...


TOPICS: Astronomy; Science
KEYWORDS: stringtheory; universe
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1 posted on 05/05/2016 6:53:04 PM PDT by MtnClimber
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To: MtnClimber

Cause that’s the way God designed it.


2 posted on 05/05/2016 6:54:07 PM PDT by Some Fat Guy in L.A. (Still bitterly clinging to rational thought despite it's unfashionability)
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To: MtnClimber

Interesting theory. Could it be because the Heavenly Father wanted it that way?


3 posted on 05/05/2016 6:54:19 PM PDT by MtnClimber (For photos of Colorado scenery and wildlife, click on my screen name for my FR home page.)
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To: MtnClimber

So we’d have more cubic footage.


4 posted on 05/05/2016 6:54:46 PM PDT by Larry Lucido (#GiveTrumpAChance and then pray we don't get fooled again)
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To: MtnClimber

Are they certain it’s only 3-dimensional?


5 posted on 05/05/2016 6:56:55 PM PDT by skr (May God confound the enemy)
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To: MtnClimber

It actually is. We only perceive three of them.


6 posted on 05/05/2016 6:59:19 PM PDT by E. Pluribus Unum ("If voting made any difference they wouldn't let us do it." --Samuel Clemens)
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To: MtnClimber

Because space is made of Up, Down, and Sideways.


7 posted on 05/05/2016 6:59:42 PM PDT by Arthur McGowan
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To: MtnClimber

Are the liberals trying to blame us for the lack of extra dimensions?
“Universe limited to 3 dimensions—women and minorities hit hardest by shortage.”


8 posted on 05/05/2016 6:59:44 PM PDT by The Continental Op
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To: skr

Flatlanders are always surprised.


9 posted on 05/05/2016 7:01:02 PM PDT by Cvengr ( Adversity in life & death is inevitable; Stress is optional through faith in Christ.)
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To: MtnClimber

Because they made all those stupid glasses with a red lens and a blue lens.

One more dimension and we’d have to have another eye.....like my cousin Sam.


10 posted on 05/05/2016 7:01:17 PM PDT by blueunicorn6 ("A crack shot and a good dancer")
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To: MtnClimber

< inhale > ... ‘ere.


11 posted on 05/05/2016 7:01:31 PM PDT by XEHRpa
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To: Larry Lucido

Some things look really good in 3D.

And where would we be without ice cubes???


12 posted on 05/05/2016 7:01:35 PM PDT by disndat
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To: skr

Four dimensions, actually, including time.

In any case, we are completely unable to perceive other dimensions, even if they did exist. With everything in the physical world describable in terms of the x, y, and z axes and time, what possible use is there for another dimension?


13 posted on 05/05/2016 7:01:47 PM PDT by exDemMom (Current visual of the hole the US continues to dig itself into: http://www.usdebtclock.org/)
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To: disndat

I once lived in a two-dimensional universe. It got kind of boring. All the women were built like Calista Flockhart.


14 posted on 05/05/2016 7:02:36 PM PDT by Larry Lucido (#GiveTrumpAChance and then pray we don't get fooled again)
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To: MtnClimber
"when the number of spatial dimensions was approximately three"

Can anyone explain to me how there can be a non-integer number of dimensions?

If the number of dimensions was approximately three, might there have at one time been pi dimensions?

15 posted on 05/05/2016 7:03:35 PM PDT by who_would_fardels_bear
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To: E. Pluribus Unum

You don’t perceive time? you are in another universe! ;-)


16 posted on 05/05/2016 7:05:44 PM PDT by Arlis
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To: Arlis

I was going to say time, but time and gravity are so intimately intertwined that it’s not really a single dimension.


17 posted on 05/05/2016 7:06:38 PM PDT by E. Pluribus Unum ("If voting made any difference they wouldn't let us do it." --Samuel Clemens)
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To: Larry Lucido

Flockhart...Flockhart...

Sounds familiar. Actor that played a lawyer?

I ain’t gonna look.


18 posted on 05/05/2016 7:07:02 PM PDT by disndat
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To: MtnClimber

I once heard Heaven is actually a different dimension.


19 posted on 05/05/2016 7:07:54 PM PDT by make no mistake
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To: MtnClimber

What do The 5th Dimension think about this?


20 posted on 05/05/2016 7:08:32 PM PDT by aomagrat (Gun owners who vote for democrats are too stupid to own guns.)
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