Posted on 05/25/2006 1:35:30 PM PDT by Ben Mugged
Scientists at Duke and Rutgers universities have developed a mathematical framework they say will enable astronomers to test a new five-dimensional theory of gravity that competes with Einstein's General Theory of Relativity.
Charles R. Keeton of Rutgers and Arlie O. Petters of Duke base their work on a recent theory called the type II Randall-Sundrum braneworld gravity model. The theory holds that the visible universe is a membrane (hence "braneworld") embedded within a larger universe, much like a strand of filmy seaweed floating in the ocean. The "braneworld universe" has five dimensions -- four spatial dimensions plus time -- compared with the four dimensions -- three spatial, plus time -- laid out in the General Theory of Relativity.
The framework Keeton and Petters developed predicts certain cosmological effects that, if observed, should help scientists validate the braneworld theory. The observations, they said, should be possible with satellites scheduled to launch in the next few years.
If the braneworld theory proves to be true, "this would upset the applecart," Petters said. "It would confirm that there is a fourth dimension to space, which would create a philosophical shift in our understanding of the natural world."
~snip~ "When we estimated how far braneworld black holes might be from Earth, we were surprised to find that the nearest ones would lie well inside Pluto's orbit," Keeton said.
Petters added, "If braneworld black holes form even 1 percent of the dark matter in our part of the galaxy -- a cautious assumption -- there should be several thousand braneworld black holes in our solar system."
(Excerpt) Read more at sciencedaily.com ...
Sorry for the double post - I boo boo'ed.
EXACTLY.
But there is something wrong with our present theory of gravity on large spatial scales. Too many epicycle corrections are piling up, when any lesser theory would just have been rejected by now as falsified by observation. (DM, DE, galactic rotation curves, etc).
From Book 1, Theophilous of Antioch
Infinity is holding a mirror in front of a mirror and seeing the reflection of a reflection of a reflection of a reflection of a reflection of a reflection of a reflection of a reflection......
Where'd you get that explanation? I really like that one because it allows me to'see' the idea.
There are only three physical dimensions; God does not **** with our heads. The only place you will ever see more than three dimensions is in linear programming applications and the like.
I intended this -in our existence/in reality- to limit the realm of my expression. Math is not reality but it 'speaks' of reality.
Most everything you said looked right to me, except you used z in place of t in the c2 term (I assume that's a typo) - and the metrics you use all describe flat spacial geometries. Different geometries emerge when non-diagonal components appear in the metric tensor/matrix in the presence of a gravitational field (things start getting complicated then) - Einstein's gravitational equation dictates how this occurs. Assuming that this 4th spacial dimension has a localized geometry, I'm making an educated guess that the measurable effects would be that gravity becomes much stronger at super-short distances. (What distance, I don't know - experiment rules out anything greater than a cm or so, I think.)
For those interested, see things like quadratic forms or metric spaces, etc.
Most people will be deterred once they actually find out what goes into basic general relativity physics - not because it's too difficult in principle, but because it's, well, boring. Riemannian geometry is what it's all about, and unless you have a vested interest in learning it, it's all a lot of tedious algebra.
WALOGIMBAT
Now this has me confused!
Nice post.
Without
Any
Loss
Of
Generality
It
May
Be
Assumed
That
There are four according to the text: length, width, depth, and height.
See! I told you... us scientists are sexy!
Er, most of us... okay some of us... a few of us...
Okay... Just Lisa Randall is sexy.
Its not like the idea is brand new, and Antares Dawn was written only 10 years ago or so.
Actually I read Antares Dawn in high school and graduated in 89.
There are some FR folks who think Radio Astronomer is sexy ... I cannot say, personally, since I've never met him. But such notions are logical since Astronomy deals with the big and that leaves lots of room for imagination.
I had seen the second copyright date. It was copywritten originally in 1986. 20 years ago, this guy must have some physicist friends. Wait, just looked him up, the guy is a real Rocket Scientist!
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