String Theorists Squeeze Nine Dimensions Into Three

In the February 25 Issue:

String theorists squeeze nine dimensions into three

Simulation suggests extra spatial directions failed to thrive

By Devin Powell

Web edition : Friday, January 13th, 2012

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A simulation of the early universe using string theory may explain why space has three observable spatial dimensions instead of nine.

The leading mathematical explanation of physics goes beyond modern particle theory by positing tiny bits of vibrating string as the fundamental basis of matter and forces. String theory also requires that the universe have six or more spatial dimensions in addition to the ones observed in everyday life. Explaining how those extra dimensions are hidden is a central challenge for string theorists.

“This new paper demonstrates, for the first time, that our 3-D space appears naturally … from the 9-D space that string theory originally has,” says Jun Nishimura of the High Energy Accelerator Research Organization in Tsukuba, Japan. He and his colleagues will publish their findings in an upcoming issue of Physical Review Letters.

In the simulation, the universe starts off as a tiny blob of strings that is symmetric in nine different dimensions. As the strings interact, a random energy fluctuation — provided by the quantum laws that govern these small scales — breaks the symmetry. Three dimensions balloon outward, leaving the other six stunted at a billionth of a trillionth of a trillionth of a centimeter, far too small to be detected.

Applying string theory to the beginning of the universe in this way has long proven difficult. That’s because the math included in traditional versions of the theory can be solved only when strings interact weakly at low temperatures, not in the seething maelstrom that existed moments after the Big Bang.

To tackle the extreme energies of the Big Bang, Nishimura and his team had to recast one version of string theory, called IIB, as grids of equations that could be fed into a supercomputer. Limited by the power of this computer, the researchers could track the interactions of no more than 32 strings for the first split second of history.

For some physicists, this way of approximating string theory is too oversimplified to be believable. “Frameworks like the one they're using … lack a lot of other stuff that goes into trying to make a realistic model,” says Shamit Kachru, a theoretical physicist at Stanford University.

To prove the usefulness of the new approach, Nishimura’s team will need to study times much later in the universe’s history, comparing their results against real observations of how matter is distributed across the universe.

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Comments 9

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So "string theory" tells us we live in a 3-dimensional space?

Brilliant! But we already knew that.

And notice that anything regarding the mechanism for reducing the hypothetical "extra dimensions" is completely untestable.

In fact untestability is the hallmark of "string theory".

For over 44 years this postmodern Platonic pipe-dreaming has yet to come up with a single definitive prediction that is prior, feasible, quantitative, non-adjustable and unique to "string theory".

When "string theory" can actually make a testable definitive prediction, then that would be something worth knowing.

Until then, hold the hype, please.

Robert L. Oldershaw
Discrete Scale Relativity

knecht

Jan. 17, 2012 at 10:15am
Isn't it worthwhile to examine the ramifications of string theory, and to attempt to elaborate it as fully as possible? Right now it still seems rather esoteric, but just because the theory hasn't been brought to complete fruition has no bearing on its ultimate truth or falsity.

Gary McLoughlin

Jan. 18, 2012 at 10:53am
This was an interesting article. I don't agree with Mr. Oldershaw because apparently he doesn't realize that some readers want to hear about different ideas as they are explored. If you're not interested in string theory, perhaps there are other things you could spend your time on? Until then, hold the negativity please.

Aaron Martins

Jan. 20, 2012 at 9:56am
I live Fez, Moracco 22 year. Bad Place.

said mohammed

Jan. 20, 2012 at 9:56am
Interesting and well written article.

I don't know if there is anything to string theory or not. And speaking just as a total amateur who has trouble finding the square root key on his slide rule, it has always bothered me about string theory that at the big bang only three dimensions expanded while the other dimensions stayed small. That was too convenient. Maybe this new paper will lay that question to rest.

Marty

Jan. 23, 2012 at 11:05am
The health and progress of science depend upon definitive predictions which are prior, feasible, quantitative, non-adjustable and unique to the theory being tested.

Throughout Einstein's career he was a master at identifying the definitive predictions that revealed whether or not his ideas were correct. This is how science is supposed to work.

In the case of "string theory", "WIMPs", the "multiverse" and so much more in postmodern theoretical physics the critical scientific requirement of definitive predictions is sadly lacking.

Even after 44 years there is no formal "string/brane theory", far less a single definitive prediction.

If you like the faith-based or authority-based approaches of pseudoscience, be my guest. But I say no definitive predictions = no science.

I do value the speculative exploration of ideas, but this should not be confused with testable science. At least not if we want something more than pipe-dreaming glass-bead games.

Robert L. Oldershaw
Discrete Scale Relativity
Discrete Fractal Cosmology

knecht

Jan. 23, 2012 at 11:08am
As another amateur I feel that string theory and others try to fit the facts to their theories. Even my favorite, plasma universe carried forward by W Thornhill, seems to be sliding toward emphasizing a capacitor aspect(correctly) although fueled by Birkeland Currents instead of neutrino input as I view it.

Now that our heliospheric compression is nearly max, and then will shortly discharge as a non locality event ( I wonder what they will call it? A double-layer plasma break? An absorbtion of all but 3 dimensions? ) the scientific findings that were able to be defined with the additional compression will then fade into mythology as they have so many cycles (5,000 y) before.
Of course, this time the solar sail was to provide energy so to establish this ephemeral compression as a permanent fixture here on E. The Greeks hubris comes to mind.

kathleen sisco

Jan. 23, 2012 at 1:38pm
String theorists (and the rest of us) would do well to remember that the three dimensions that today seem so much a natural and rational part of spacetime were invented by Rene Descartes in the 17th century. They are modeled on the regular hexahedron, or cube, which Fuller (1979) has shown is not the coordinate system nature is actually using.

“The prime barrier to humanity’s discovery and comprehension of nature is the obscurity of the mathematical language of science. Fortunately, however, nature is not using the strictly imaginary, awkward, and unrealistic coordinate system adopted by and taught by present-day academic science.”
––Fuller, R. B. (1979). Synergetics 2. New York: Macmillan Publishing Co., p. xxiii, p. 566.

Robert Chester

Jan. 31, 2012 at 11:06am
Im not a scientist but i have a relenting almost compulsion with the values 1, 3 and 9 and thier easily understood interactions. I think instead of a 1-10 number system, a 1-9 system should be use ie. three sets of 9 and nine sets of those three and so on to infinity... or easier explained 1 obviously the most basic value, 3 sets of 1 = 3 and 3 set of 3 = 9.. So nine set of 1 = 9 nine sets of 3 is 27 nine set of 27 is 243. These key values can alway be easly understood and reduced with the power of 3s. So when numbers huge and unmanagable the value 243 could be easliy understood and expession as 1. My head floods with the possibilities, I can do amazing mental math in a 3-d or "cubed" world with this idea in mind. Is there an algorythm, if thats the right word, or math that works like this?

Casey Orr

Feb. 22, 2012 at 4:11pm

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