A group of three researchers from KEK, Shizuoka University and Osaka University has for the first time revealed the way our universe was born with 3 spatial dimensions from 10-dimensional superstring theory in which spacetime has 9 spatial directions and 1 temporal direction. This result was obtained by numerical simulation on a supercomputer.

According to Big Bang cosmology, the universe originated in an explosion from an invisibly tiny point. This theory is strongly supported by observation of the cosmic microwave background and the relative abundance of elements. However, a situation in which the whole universe is a tiny point exceeds the reach of Einstein's general theory of relativity, and for that reason it has not been possible to clarify how the universe actually originated.

In superstring theory, which is considered to be the "theory of everything", all the elementary particles are represented as various oscillation modes of very tiny strings. Among those oscillation modes, there is one that corresponds to a particle that mediates gravity, and thus the general theory of relativity can be naturally extended to the scale of elementary particles. Therefore, it is expected that superstring theory allows the investigation of the birth of the universe. However, actual calculation has been intractable because the interaction between strings is strong, so all investigation thus far has been restricted to discussing various models or scenarios.

Superstring theory predicts a space with 9 dimensions, which poses the big puzzle of how this can be consistent with the 3-dimensional space that we live in.

A group of 3 researchers, Jun Nishimura (associate professor at KEK), Asato Tsuchiya (associate professor at Shizuoka University) and Sang-Woo Kim (project researcher at Osaka University) has succeeded in simulating the birth of the universe, using a supercomputer for calculations based on superstring theory. This showed that the universe had 9 spatial dimensions at the beginning, but only 3 of these underwent expansion at some point in time.

This work will be published soon in *Physical Review Letters*.

In this study, the team established a method for calculating large matrices (in the IKKT matrix model), which represent the interactions of strings, and calculated how the 9-dimensional space changes with time. In the figure, the spatial extents in 9 directions are plotted against time.

If one goes far enough back in time, space is indeed extended in 9 directions, but then at some point only 3 of those directions start to expand rapidly. This result demonstrates, for the first time, that the 3-dimensional space that we are living in indeed emerges from the 9-dimensional space that superstring theory predicts.

This calculation was carried out on the supercomputer Hitachi SR16000 (theoretical performance: 90.3 TFLOPS) at the Yukawa Institute for Theoretical Physics of Kyoto University.

It is almost 40 years since superstring theory was proposed as the theory of everything, extending the general theory of relativity to the scale of elementary particles. However, its validity and its usefulness remained unclear due to the difficulty of performing actual calculations. The newly obtained solution to the space-time dimensionality puzzle strongly supports the validity of the theory.

Furthermore, the establishment of a new method to analyze superstring theory using computers opens up the possibility of applying this theory to various problems. For instance, it should now be possible to provide a theoretical understanding of the inflation that is believed to have taken place in the early universe, and also the accelerating expansion of the universe, whose discovery earned the Nobel Prize in Physics this year. It is expected that superstring theory will develop further and play an important role in solving such puzzles in particle physics as the existence of the dark matter that is suggested by cosmological observations, and the Higgs particle, which is expected to be discovered by LHC experiments.

**Explore further:**
String theory researchers simulate big-bang on supercomputer

## rawa1

The whole trick is based on the fact, the density fluctuations of gas are forming n-spheres in hyperspace and the energy density depends on the volume/surface ratio of these hyperspheres. Surprisingly, for 3D hyperspheres this ratio is highest one, the radius of both circle (2D sphere), both 4D hypersphere is smaller with respect to its surface, than at the case of 3D sphere. It's because the transverse waves are spreading through surface of particles forming the volume of environment and the slower their speed is, the larger is the space which they form. It explains too, why the density fluctuations of dense gas converge to packed spheres with increasing density of that gas.

## rawa1

Before some time Dr Karch and Dr Randall demonstrated too, that a universe filled with equal numbers of branes and anti-branes will naturally come to be dominated by 3-branes and 7-branes because these are the least likely to run into their anti-brane counterparts and thus be annihilated.

http://xxx.lanl.g.../0506053

## jdbertron

Can we stop making such false statements about the big bang please ? It's about as absurd as saying it was purple.

## rawa1

## Nanobanano

that actually EXACTLY what all the major BB theorists continue to say publicly, to this day.

I was just watching a brand new documentary on Nat Geo 2 days ago, and they used that same language again.

## vega12

## that_guy

Seeing as so far it is kind of a waste of time until we can pull string theory into the empirical realm, I understand why they were hesitant to waste good supercomputing time on this.

Well, if anyone really thought that this was an important task to model, they could have done it a decade ago at the same speed...

But I digress, I suppose string theory is interesting enough that we should throw a few resources at it. Hopefully someday it will even make predictions.

Until then, third tier "super" computers are good enough.

## Osiris1

## Sean_W

BTW, does anything in string theory make sense of why the original 10 dimensions were there to become our 3 1 universe or why there is only one time dimension--both before and after the expansion?

## Skultch

You are both correct and make valid points. However, we people that understand these things are not really the intended audience of these shows. They dumb it down to attract NEW laypersons, usually children that understand what explosions are, but not "inflation," and who will eventually figure this out if they really care. All I'm saying is, I understand why the writers do this. I might not if I were in their shoes, but I understand. I do similar things when explaining technical IT/networking issues to my customers. Not all viewers are aspiring physicists.

## Callippo

## Callippo

Of course, the above is valid only under the assumption of Euclidean geometry, but the geometry formed with hypersphere packing in nonEuclidean and the number of dimensions is apparently higher there (about 245 dimensions or so).

## dtyarbrough

## Callippo

## BIG COCK

@rawa1

Completely and utterly false. Surfaces get more massive as the number of dimensions gets larger, and n-spheres are no exception. The surface to volume ratio of hyperspheres is in particular n/R, where n is the number of dimensions and R is the radius, and it is obvious that the ratio becomes larger as you pass to higher-dimensional embedding spaces.

I'm curious: do you just invent facts for fun, or do you actually believe the garbage that you constantly seem to post?

## Foolish1

## Callippo

http://mathworld...._900.gif

http://en.wikiped...ace_area

## Tangent2

## MorituriMax

nanobanan, whatever

No, it isn't. EXPANSION OF SPACE TIME, not EXPLOSION IN SPACE.

## MorituriMax

Dec 24, 2011## 80centuries

## Callippo

## Callippo

"..This goes back to the pre-arXiv days, before many of our current graduate students were even born, but some of us are old enough to remember similar claims being made back in the late 1980s. For example theres the 1989 Brandenberger-Vafa paper claiming that string theory predicts 3 dimensions, using a string gas cosmology. I dont remember if there was a finally, physicists find a way to make a prediction based on string theory press release back in 1989 or not..."

## Seeker2

So originally the energy density of the universe was very high. For the guys who claim the total energy of the universe is zero, maybe all this initial energy is balanced out by what might be the negative energy of compacted spacetime. Seems strange though.

## Callippo

http://people.rit...4565.jpg

## Seeker2

## Callippo

## Seeker2

## billyphillips7

## Callippo

## Seeker2

## billyphillips7

## Seeker2

## Cynical1

Does this make the whole experience fractal or ergodic?

And why does the header say 10 dimensions and the article only says 9? Are they saying that our 3 spatial dimensions count as the 10th?

And lastly - so Calippo and Rawa1 are the same person? They do sound the same in the way they describe AWT as ripples in a pond (or sink or bathtub or puddle on your drive after a rain....)

## Callippo

## TabulaMentis

I am curious how something can come from nothing as the string theorists proclaim. Maybe you could provide some entertainment in explaining that to us laypersons? Also explain how the entire universe was at one time compressed into a tiny speck.

## TabulaMentis

While you are at it create a single line diagram similar to the one found on this Wikipedia page:

http://en.wikiped...eory.svg

It should be very easy for you to add to that illustation what existed prior to the BB, what caused the BB and how the nine spatial dimensions, plus the one temporal dimension were created. The Wikipedia illustration is very concise and needs to be extended.

## TabulaMentis

I almost forgot. Please include the matrices in the single line diagram.

## Shifty0x88

Not sure if it is the same, so don't quote me on that

## Urgelt

So. I'm struggling with the notion that this matrix computation yields "strong proof" of anything.

What they did amounts to a ginormous simulation. Ginormous to us, surely, but not as ginormous as the real thing: the universe, and every particle, wave, or whatever-it-is in it, over around 14 billion years, give or take. They had to take some shortcuts to simulate all of that on a single supercomputer over a manageable, human-scale period of time. And there, my friends, is the rub. The design of the simulation, not the physical universe, determined the outcome.

Simulations are interesting, certainly, but until we see string theory generate hypotheses testable through experimentation, there's no "strong proof."

## numerized

Dec 27, 2011## Callippo

## taylone

## AmritSorli

where time is a numerical order (sequence) of material change

see more on

http://www.physor...ion.html

string theory has no experimental basis, it is a pure mathematical model with no correspondence in physical world

## rawa1

The question, whether these postulates can be reconciled with another postulates of string theory (like the Lorentz symmetry) in reliable way is another thing. Although it may not be quite apparent for laymans, the approach of string theory to reconciliation of quantum mechanics with special relativity is quite straightforward - it's actually way simpler, than it should/could be. But even the very simple approaches lead into complex math at the case of relativity and quantum mechanics, because these two theories are complex by itself.

## Eoprime

I vote you down for a.) Ätherwavenonsense b.) constant spamming c.) putting meaningless words together

And guess what, i even report your AWT posts because of pseudoscience (like NeutronRepulsion). now please get lost and take Omatrumbum withyou.

Eo

## rawa1

There is nothing non-physical on dense aether model with compare to string theory. It's very simple and natural model of reality and all main aspects of which can be modelled with common water surface. With compare to string theory and various ad-hoced theories. As you can see above, the dense aether model enables even to explain the strengths and weakness of these theories.

No concept is nonsense, until you prove the opposite.

## Seeker2

## Seeker2

So basically AWT is a Genesis 1 update.

## rawa1

## Seeker2

Must not be too much. I thought you were a steady state man.

## rawa1

AWT just says, from sufficiently distant perspective the steady state and big bang models will become indistinguishable each other. The uniform distribution of redshift indicates, it's of anthropocentric origin but this uniformity is violated with Doppler anisotropy of the red shift.

## rawa1

## rawa1

## rawa1

## Callippo

Note that this phase transform is of gradualist nature, it proceeds in isolated islands ("galaxies") at different stages and we can find the residua of previous phase all around us - actually in the similar way, like the Big Bang residua.

## Seeker2

So AWT theory would seem to be much more effective describing the sectarian community than any possible physical application.

Total ignorance should be a sufficiently distant perspective.

## Callippo

## HoraceShmorace

## Callippo

## Seeker2

Right. Keep it fuzzy so it can't be tested. That way nobody can prove it's wrong.

Right. Advanced technology is basically black magic.

## Callippo

http://www.aether...part.gif

Whereas the short-wavelength photons and heavier particles travel across density gradient of gravity field, the longwavelength photons and neutrinos are traveling in the opposite direction. In this way the subtle portion of observable matter always travels against time arrow defined with entropy flux. Bellow human observer scale most of massive objects tend to evaporate, above this scale they collapse with gravity.

## Seeker2

## Callippo

## Callippo

## Seeker2

## Seeker2

## Callippo

## Seeker2

## Cynical1

## ED__269_

## Seeker2