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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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To: E. Pluribus Unum

4 of them. We experience time, x, y, z and who’s to say they’re aren’t much more.


61 posted on 05/05/2016 8:07:14 PM PDT by Fhios (Going Donald Trump is as close to going John Galt as we'll get.)
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To: MtnClimber

62 posted on 05/05/2016 8:07:26 PM PDT by UCANSEE2 (Lost my tagline on Flight MH370. Sorry for the inconvenience.)
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To: exDemMom
In any case, we are completely unable to perceive other dimensions, ...

Speak for yourself.

63 posted on 05/05/2016 8:09:00 PM PDT by UCANSEE2 (Lost my tagline on Flight MH370. Sorry for the inconvenience.)
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To: make no mistake
I once heard Heaven is actually a different dimension.

it would almost have to be.

64 posted on 05/05/2016 8:16:43 PM PDT by BipolarBob (I'm so open minded that you should only think like me.)
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To: BipolarBob; make no mistake
I've also heard a theory that Heaven is a place on earth.


65 posted on 05/05/2016 8:20:46 PM PDT by Larry Lucido (#GiveTrumpAChance and then pray we don't get fooled again)
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To: MtnClimber

Well WTF, did they think it was flat? Were there actually ignorant flat spacers out there?


66 posted on 05/05/2016 8:22:52 PM PDT by DesertRhino ("I want those feeble minded asses overthrown,,,)
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To: MtnClimber

Well WTF, did they think it was flat? Were there actually ignorant flat spacers out there?


67 posted on 05/05/2016 8:22:55 PM PDT by DesertRhino ("I want those feeble minded asses overthrown,,,)
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To: MtnClimber

so let me see...

first there were zero dimensions, then there was a BANG, and then there was 1 -> 2 -> 2.9XXXXXXX dimensions. great! spontaeous dimensional order generation from nothing at gazillion degrees, etc., etc, and then dimension 4 kicks in right at 3.0, and disorder started, ugh! but wait, thanks to disorder increasing (time), we reach the point of disorder where solar systems form and then seas and then organic chemicals (ain’t disorder great), and finally cells, and you know the rest.

SMH amazing! these people must be ohhh soooo smart.


68 posted on 05/05/2016 8:25:14 PM PDT by dadfly
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To: MtnClimber
It's not, it's 4 dimensional.
69 posted on 05/05/2016 8:27:33 PM PDT by <1/1,000,000th%
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To: MtnClimber

Because if it wasn’t we’d bump our noses all the time.


70 posted on 05/05/2016 8:28:33 PM PDT by InvisibleChurch
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To: MtnClimber

M-Theory claims there are ii dimensions.


71 posted on 05/05/2016 8:31:11 PM PDT by onedoug
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To: T-Bone Texan
Mass is a dimensional phenomena. It appears discrete (ie, real) and it allows an extremely straightforward and very simple explanation of what we call gravity (the essential first step to anti-gravity engines is knowing what in the hell gravity is in the first place). The complete theory (at least as far as I've gotten it) generally correlates to Einstein's relativity pretty well but it needs to be renamed to the theory of absolutivity because all five dimensions now have a definable absolute zero value, the only caveat being that the generally recognized three dimensions have an absolute zero vector, and the actual point of origin becomes essentially irrelevant.

The trick is to recognize that time has an absolute value of zero at the event horizon of a black hole, so, in theory, whatever exists beyond that horizon is traveling backwards in time (which may allow a general explanation of eternal time because everything eventually collapses back to the beginning and the cycle repeats).

It really is an elegant theory in that it seems to explain the observable universe very concisely, and has a bunch of really interesting corrolaries. For example one corollary states that a massive body at zero absolute velocity has zero gravity, which can be used as the definition of absolute velocity in the first place. Another one is that the universal gravitational constant is neither universal nor constant but is a variable.

Using a single datum point, the acceleration of gravity on Earth, I was able to calculate that the absolute velocity of our solar system is ~0.1c (29,999 km/sec), but I also believe that I screwed up the calculation of the permitivity of free space, so I'm not ready to vigorously defend that calculation.

Like I said, a work in progress.

72 posted on 05/05/2016 8:31:37 PM PDT by lafroste
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To: E. Pluribus Unum; MtnClimber

“It actually is. We only perceive three of them.”

Yes, we only PERCEIVE three, but that does NOT mean that there are not other, real dimensions, which are too small for us to even try to perceive, much less move into.


73 posted on 05/05/2016 8:33:41 PM PDT by 2harddrive
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To: disndat
Do you disbud the females? :-)

Reminds of a joke told by a Nebraskan:

Why do they have astroturf on the field at the University of Iowa stadium?

To keep the cheerleaders from grazing during half-time.

74 posted on 05/05/2016 8:33:56 PM PDT by pierrem15 ("Massacrez-les, car le seigneur connait les siens")
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To: tinyowl

You’ve been reading too much Parmenides or Plotinus.


75 posted on 05/05/2016 8:35:37 PM PDT by pierrem15 ("Massacrez-les, car le seigneur connait les siens")
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To: MtnClimber

Not too hot, not too cold, just right!


76 posted on 05/05/2016 8:38:37 PM PDT by frithguild (The warmth and goodness of Gaia is a nuclear reactor in the Earth's core that burns Thorium)
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To: T-Bone Texan

BTW: it also easily explains the so called dual nature of light (both wave and particle behavior). I have done some work on trying to figure out how to test the theory, but so far, it looks like it would take a budget of roughly the entire cost of WWII. A bit pricey for a weekend warrior to put together.


77 posted on 05/05/2016 8:39:33 PM PDT by lafroste
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To: who_would_fardels_bear
"Consult the Book of Cosmology!"

"Three shall be the number of thy dimensions, and the number of thy dimensions shall be three. Five is right out...."

78 posted on 05/05/2016 8:41:33 PM PDT by grey_whiskers (The opinions are solely those of the author and are subject to change without notice.)
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To: tinyowl

“Seriously, dimensions are a property of the mind”

You’re spot on. I was just going to say the same thing.


79 posted on 05/05/2016 8:44:38 PM PDT by Electric Graffiti (DEPORT OBOLA VOTERS)
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To: Popman

“Elements that make up the planet: Earth, wind, water...
Father, Son, Holy Spirit...
H2O...three molecules...
CO2....Three molecules...
Liquid, solid, vapor...

Just to name a few...

.............

Don’t forget paper, rock, scissors.


80 posted on 05/05/2016 8:46:22 PM PDT by aMorePerfectUnion (BREAKING.... Vulgarian Resistance begins attack on the GOPe Death Star.....)
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