Proposed Spacetime Structure Could Provide Hints for Quantum Gravity Theory

Spacetime, which consists of three dimensions of space and one time dimension, is such a large, abstract concept that scientists have a very difficult time understanding and defining it. Moreover, different theories offer different, contradictory insights on spacetime’s structure. While general relativity describes spacetime as a continuous manifold, quantum field theories require spacetime to be made of discrete points. Unifying these two theories into one theory of quantum gravity is currently one of the biggest unsolved problems in physics.

In an attempt to better understand spacetime, mathematical physicist Achim Kempf of the University of Waterloo has proposed a new possible structure of spacetime on the Planck scale. He suggests that spacetime could be both discrete and continuous at the same time, conceivably satisfying general relativity and quantum field theories simultaneously. Kempf’s proposal is inspired by information theory, since information can also be simultaneously discrete and continuous. His study is published in a recent issue of Physical Review Letters.

“There are fiercely competing schools of thought, each with good arguments, about whether spacetime is fundamentally discrete (as, for example, in spin foam models) or continuous (as, for example, in string theory),” Kempf told PhysOrg.com. “The new information-theoretic approach could enable one to build conceptual as well as mathematical bridges between these two schools of thought.”

As Kempf explains, the underlying mathematical structure of information theory in this framework is sampling theory - that is, samples taken at a generic discrete set of points can be used to reconstruct the shape of the information (or spacetime) everywhere down to a specific cutoff point. In the case of spacetime, that cutoff would be the natural ultraviolet lower bound, if it exists. This lower bound can also be thought of as a minimum length uncertainty principle, beyond which structural properties cannot be precisely known.

www.physorg.com...

It just keeps getting more interesting. Gravity is such a mystery. Wether spacetime consists of discreet points or is continuos has been a raginf debate for a long time.

With so many mysteries in both quantum and relatavistic physics it amazes me that they can work on these problems without brain dripping from their noses.

As strange as gravity is and its unwillingness to be tamed, makes one think (at least makes me think) that we may never no the answer.

Then again a straightforward non-multiverse, quantum foam, dark something or another invoking answer would just be a huge let down

[edit on 14-1-2010 by constantwonder]

Explanation: S&F!

They are making it way harder than it needs to be and in fact they have already got the answer!

Here is why....

Remember that Wilkinson Microwave Anisotrophy Map!

Well the scientists were all waiting around the monitor, waiting for the downloaded data to be displayed and a discussion broke out over whether it would vindicate GR or visa versa QM!

So the technician puts the data up on the screen and it was homogenous and isotrophic in appearance and the GR supporters all cheered. But the technician then turned up the CONTRAST and suddenly the picture became anisotrophic and imhomogenous and then all the QM supporters all cheered! Both veiws of the data were completely accurate as the data had not changed. ONLY THE WAY IT WAS VIEWED! And the algorythym to do this was a contrasting algorythym and it already EXISTS!

GR is like viewing the universe as one would view an orange at a distance of about 10mtrs and at that SCALE one can not accurately DISCERN any very small topological differences i.e. the orange skin looks orange and smooth. Where as QM is like viewing the universe as one would view an orange at a distance of less than 1mm and at that SCALE on can not accurately DISCERN any extremely large topological differences i.e. The orange skin looks mainly orange but there are other coloured spots and the texture is very rough! The orange didn't change, but the CONTRAST between different SCALES of POV DID!

Personal Disclosure: THEY KNOW THIS! They don't want to put themselves out of a job and this is why they keep coming up with this BS. Its freaking fixed already. :shk:

Seriously, I have to agree with you there--that would be a huge let down. I'm counting on it all being terribly exotic and not in the least mundane. I have to put my membership to good use there before it expires, will see if I can find the paper (hope it's available in my bundle). Do you have a link to the article you posted from? Oh there it is. Thanks for the link.

[edit on 14-1-2010 by elfie]

reply to post by OmegaLogos

Never heard of it, I'll check that out. Also I agree with you, it seems that industry and scientists are play acting in order to show that they are working hard to discover this or that when in reality it may have been figured out decades ago and they have to show it to the public as if they have been working on it. Can't let the sheep know that we have had advance techology for decades but kept it to ourselves and the elite in order to have control.

Mod Note: Excessive Quoting – Please Review This Link

[edit on Thu Jan 14 2010 by Jbird]

I believe they have solved gravity, some of those strange craft that people are seeing are ours, actually I think the Germans solved it in the late thirties or early forties and brought the technology to the U.S. after the WW11...

S&F

Interesting information.

Granted, a bit over my head but still fascinating.