Physicists find way to 'see' extra dimensions (Forwarded)

University Communications
University of Wisconsin-Madison
Madison, Wisconsin

Contact:
Gary Shiu, 608-265-3285

February 2, 2007

Physicists find way to 'see' extra dimensions
By Jill Sakai

Peering backward in time to an instant after the big bang, physicists at
the University of Wisconsin-Madison have devised an approach that may help
unlock the hidden shapes of alternate dimensions of the universe.

A new study demonstrates that the shapes of extra dimensions can be "seen"
by deciphering their influence on cosmic energy released by the violent
birth of the universe 13 billion years ago. The method, published today
(Feb. 2) in Physical Review Letters, provides evidence that physicists can
use experimental data to discern the nature of these elusive dimensions --
the existence of which is a critical but as yet unproven element of string
theory, the leading contender for a unified "theory of everything."

Scientists developed string theory, which proposes that everything in the
universe is made of tiny, vibrating strings of energy, to encompass the
physical principles of all objects from immense galaxies to subatomic
particles. Though currently the front-runner to explain the framework of
the cosmos, the theory remains, to date, untested.

The mathematics of string theory suggests that the world we know is not
complete. In addition to our four familiar dimensions -- three-dimensional
space and time -- string theory predicts the existence of six extra
spatial dimensions, "hidden" dimensions curled in tiny geometric shapes at
every single point in our universe.

Don't worry if you can't picture a 10-dimensional world. Our minds are
accustomed to only three spatial dimensions and lack a frame of reference
for the other six, says UW-Madison physicist Gary Shiu, who led the new
study. Though scientists use computers to visualize what these
six-dimensional geometries could look like, no one really knows for sure
what shape they take.

The new Wisconsin work may provide a long-sought foundation for measuring
this previously immeasurable aspect of string theory.

According to string theory mathematics, the extra dimensions could adopt
any of tens of thousands of possible shapes, each shape theoretically
corresponding to its own universe with its own set of physical laws.

For our universe, "Nature picked one -- and we want to know what that one
looks like," explains Henry Tye, a physicist at Cornell University who was
not involved in the new research.

Shiu says the many-dimensional shapes are far too small to see or measure
through any usual means of observation, which makes testing this crucial
aspect of string theory very difficult. "You can theorize anything, but
you have to be able to show it with experiments," he says. "Now the
problem is, how do we test it?"

He and graduate student Bret Underwood turned to the sky for inspiration.

Their approach is based on the idea that the six tiny dimensions had their
strongest influence on the universe when it itself was a tiny speck of
highly compressed matter and energy -- that is, in the instant just after
the big bang.

"Our idea was to go back in time and see what happened back then," says
Shiu. "Of course, we couldn't really go back in time."

Lacking the requisite time machine, they used the next-best thing: a map
of cosmic energy released from the big bang. The energy, captured by
satellites such as NASA's Wilkinson Microwave Anisotropy Probe (WMAP), has
persisted virtually unchanged for the last 13 billion years, making the
energy map basically "a snapshot of the baby universe," Shiu says. The
WMAP experiment is the successor to NASA's Cosmic Background Explorer
(COBE) project, which garnered the 2006 Nobel Prize in physics.

Just as a shadow can give an idea of the shape of an object, the pattern
of cosmic energy in the sky can give an indication of the shape of the
other six dimensions present, Shiu explains.

To learn how to read telltale signs of the six-dimensional geometry from
the cosmic map, they worked backward. Starting with two different types of
mathematically simple geometries, called warped throats, they calculated
the predicted energy map that would be seen in the universe described by
each shape. When they compared the two maps, they found small but
significant differences between them.

Their results show that specific patterns of cosmic energy can hold clues
to the geometry of the six-dimensional shape -- the first type of
observable data to demonstrate such promise, says Tye.

Though the current data are not precise enough to compare their findings
to our universe, upcoming experiments such as the European Space Agency's
Planck satellite should have the sensitivity to detect subtle variations
between different geometries, Shiu says.

"Our results with simple, well-understood shapes give proof of concept
that the geometry of hidden dimensions can be deciphered from the pattern
of cosmic energy," he says. "This provides a rare opportunity in which
string theory can be tested."

Technological improvements to capture more detailed cosmic maps should
help narrow down the possibilities and may allow scientists to crack the
code of the cosmic energy map -- and inch closer to identifying the single
geometry that fits our universe.

The implications of such a possibility are profound, says Tye. "If this
shape can be measured, it would also tell us that string theory is
correct."

The new work was funded by grants from the National Science Foundation,
the U.S. Department of Energy and the Research Corp.

IMAGE CAPTION:
[http://www.news.wisc.edu/newsphotos/...sion_art07.jpg
(518KB)]
A computer-generated rendering of a possible six-dimensional geometry
similar to those studied by UW-Madison physicist Gary Shiu.

Image: courtesy Andrew J. Hanson, Indiana University

I would just like to make a dig for LISA. We can see the Universe
300,000 years old in the shape of COBE. According to Jan Baez in
sci.physics.research graviational waves can be "seen" steming from
10^-38 sec. If this is true GCOBE would provide a test of String
Theory. I feel though that LISA is not really adaquate. LISA you see
consists of only 3 spacecraft arranged in an equllateral triangle of
size 5 million km. To get a GCOBE picture you will need a consellation
of LISAs.

Unfortunately - I must get this dig in NASA is infatuated with manned
space flight. LISA will probably never leave the ground and String
Theory will be tested exclusively by Europeans.


- Ian Parker

On a sunny day (3 Feb 2007 04:14:23 -0800) it happened "Ian Parker"
wrote in
.com:

I would just like to make a dig for LISA. We can see the Universe
300,000 years old in the shape of COBE. According to Jan Baez in
sci.physics.research graviational waves can be "seen" steming from
10^-38 sec. If this is true GCOBE would provide a test of String
Theory. I feel though that LISA is not really adaquate. LISA you see
consists of only 3 spacecraft arranged in an equllateral triangle of
size 5 million km. To get a GCOBE picture you will need a consellation
of LISAs.

Unfortunately - I must get this dig in NASA is infatuated with manned
space flight. LISA will probably never leave the ground and String
Theory will be tested exclusively by Europeans.


- Ian Parker

As t o'on the edge' experiments by the US:
I dont want to be sceptical, but had my reservations,
so far from gravity probe B we have only learned:
: When spinning a raw egg on the table, you will find that its spin rate
decreases rapidly, while a hard boiled egg spins happily at the same rate
for some time)
From http://einstein.stanford.edu/highlig...ode_story.html
More in April 2007......

Now that is good to know, but I have no expectations.....
Sam Wormley will perhaps like the math involved to correct for 'polhode'
motion...
But as to get an actual usable result it looks like different timescales
are needed.
Humanity has only flew high in hightech for say a hundred years.
Before the big comet in 2028 or there about I expect no string theory proof.
(of disproof), those string guys know that, and feel safe so far.
Would be way cool if it got proven wrong or right sooner though.

On Sat, 03 Feb 2007 00:41:11 +0000, Andrew Yee wrote:

University Communications
University of Wisconsin-Madison
Madison, Wisconsin

Contact:
Gary Shiu, 608-265-3285

February 2, 2007

Physicists find way to 'see' extra dimensions By Jill Sakai

Peering backward in time to an instant after the big bang, physicists at
the University of Wisconsin-Madison have devised an approach that may help
unlock the hidden shapes of alternate dimensions of the universe.

A new study demonstrates that the shapes of extra dimensions can be "seen"
by deciphering their influence on cosmic energy released by the violent
birth of the universe 13 billion years ago.

More crap.
Hypothesis piled upon hypoythesis with occasional minor unrelated
observational "support" that would in all likelyhood be better used
supporting a reality based phyics of the universe.




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/ _ \/ __/ _ | / _ \ / _ \/ _ |/ / / / /
/ // / _// __ |/ // / / ___/ __ / /_/ / /__
/____/___/_/ |_/____/ /_/ /_/ |_\____/____/

On 3 Feb, 14:00, Jan Panteltje wrote:
On a sunny day (3 Feb 2007 04:14:23 -0800) it happened "Ian Parker"
I dont want to be sceptical, but had my reservations,
so far from gravity probe B we have only learned:
: When spinning a raw egg on the table, you will find that its spin rate
decreases rapidly, while a hard boiled egg spins happily at the same rate
for some time)
Fromhttp://einstein.stanford.edu/highlights/hl_polhode_story.html
More in April 2007......

I don't think you are aware of what gravitational waves are. They
travel at the speed of light and pass through matter. This is why
10-38sec was quoted. LISA will in fact detect a number of phenomena
like neutron stars in close orbit and matter orbiting and falling into
black holes. Gravitational COBE will not be thermal like COBE but will
in fact extent over a number of epochs in the Universe. The only way
that LISA will be able to distinguish is spectrally. It can't even
(with 3 spacecraft) distinuisgh between the planes of polarization
with a spin 2 particle.

Now that is good to know, but I have no expectations.....
Sam Wormley will perhaps like the math involved to correct for 'polhode'
motion...
But as to get an actual usable result it looks like different timescales
are needed.
Humanity has only flew high in hightech for say a hundred years.
Before the big comet in 2028 or there about I expect no string theory proof.

A disproof is as important as a proof. I too am skeptical about string
Theory. The only scientific thing to do is to take a look and see.

As far as humanity being extinguished by a comet in 2028 is concerned
- on what do you base your assertions. - Religious fundamentalism?


- Ian Parker