Who cares about the fourth dimension?

February 3, 2009
Who cares about the fourth dimension?
Comic Gravitation (c) Florian Aigner

Austrian scientists are trying to understand the mysteries of the holographic principle: How many dimensions are there in our universe?

Some of the brightest minds of the world are doing research work in this sector - and still have not succeeded so far: Creating a unified theory of quantum gravitation is often considered to be the “Holy Grail” of modern science. Daniel Grumiller from the Institute of Theoretical Physics, Vienna University of Technology, Austria, can now at least unravel some of the mysteries of quantum gravitation. His results on black holes and gravitational waves are pretty mind-boggling - to say the least. Only recently he won the START prize and will use these funds to engage even more young physicians at the TU Vienna.

We perceive the space around us as three-dimensional. According to Einstein, time and space are inseparabely linked. Adding the time axis to our three-dimensional space makes our space-time-continuum four-dimensional. For decades, scientists have been wondering about the existence of additional dimensions so far hidden to our senses. Grumiller and his colleagues are trying the opposite approach: Instead of postulating additional dimensions, they believe that our universe could in fact be described by less than four dimensions.

“A hologram, as you find it on bank notes or credit cards, appears to show a three-dimensional picture, even though in fact it is just two-dimensional”, Grumiller explains. In such a case, reality has fewer dimensions than we would thinkit appears to have. This “holographic principle” plays an important role in the physics of space time. Instead of creating a theory of gravity in all the time and space dimensions, one can formulate a new quantum theory with one fewer spatial dimension. That way, a 3D theory of gravitation turns into a 2D quantum theory, in which gravity does not appear any more. Still, this quantum theory correctly predicts phenomena like black holes or gravitational waves.

“The question, how many dimensions our world really has, does probably not even have a proper answerprobably cannot be answered explicitly”, Grumiller thinks. “Depending on the particular question we are trying to answer, either one of the approaches may turn out to be more useful.”

Grumiller is currently working on gravitational theories which include two spatial dimensions and one time dimension. They can be mapped onto a two-dimensional gravitationless quantum theory. Such theories can be used to describe rapidly rotating black holes or “cosmic strings” - spacetime defects, which probably appeared shortly after the Big Bang.

Together with colleagues from the University of Vienna, Grumiller is organizing an international workshop, which will take place from April 14 to 24, 2009. Renowned participants, like scientists from Harvard, Princeton, the MIT and many other universities, reveal that the Viennese gravitation physicians are held in high regard internationally.

Source: TU Vienna

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Feb 03, 2009
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Feb 03, 2009
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2.7 / 5 (6) Feb 03, 2009
The interesting thing about dimensions is that they are conceptual; that is, they can be thought of as artifacts of our limited perceptual ability. Dimensions are simply a method of quantifying and describing the characteristics/parameters of an observed phenomenon. I've worked with 11 space-time dimensions and 11 time-space dimensions ( http://fractalicawakening.com ). In space-time, the dynamic/energetic aspects of the spatial dimensions are made possible by the hyperdimension of time, while in time-space, the dynamic/energetic aspects of the temporal dimensions are made possible by the hyperdimension of space. Intelligences in space-time can travel in any spatial direction they wish, but cannot travel along the hyperdimension of time. Conversely, intelligences in time-space can travel in any temporal dimension they wish, but cannot travel along the hyperdimension of space.
1.8 / 5 (5) Feb 03, 2009
we're actually in a 2 dimensional plane of existence

Water surface can be divided into many dropplets. And these droplets can be divided into another, even much smaller dropplets. After then the string and brane models would obtain a much deeper meaning.
2 / 5 (4) Feb 03, 2009
they can be thought of as artifacts of our limited perceptual ability

Not quite. For example, water surface is just two dimensional, because surface waves can follow just two mutually perpendicular directions, in which they cannot interfere mutually. We are saying, this surface has two degrees of freedom.
1.7 / 5 (6) Feb 03, 2009
The number of dimensions can be determined independently by measurements of force constant distance dependence. For example the shielding effect of boat at water surface is indirectly proportional to first power of distance, at 3D the shielding effect remains proportional the second power of distance (Newton's inverse square law for case of gravity and electromagnetic interaction), and so on.


By such way, the number of dimensions is apparently related to inertial energy spreading and it can be measured independently.
2.4 / 5 (5) Feb 03, 2009
Eh dimensions dont really exist... Just something we make up to help understand our world. Iv always thought its interesting how people think about time and space as if we are on the verge of understanding it all. I honestly believe that time is a concept humans overall wont grasp for awhile like 200 years or more. Its pretty simple if you think about it the right way tho. Thought moves in steps time doesn't thats why things that think have a very hard time understanding time. The second you stop trying to messure time you might understand it better but thats freeking impossible to do with all the clocks humans and nature make.
2 / 5 (4) Feb 03, 2009
Time is like a pressure system. It has a low and high end. At the low end of time not much is going on because its almost free of movement. At the high end of time tons of stuff is happening. I would guess that the low end pulls the high end to make even more stuff happen at any given point in time. So like the begining of time would always appear to be moving away from us as we learn more about it. Also if time does end at any given point the past would become the now and anyone at the now would be able to see back forever and possibly make guesses as to how time ends.
Feb 03, 2009
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2.3 / 5 (3) Feb 03, 2009
Yeah but its only the most relevant because its the most easly understood stance. The problem with that is the common understanding is almost always wrong.
1.5 / 5 (8) Feb 04, 2009
My level of understanding is definitelly NOT common in this moment.
2.7 / 5 (3) Feb 04, 2009
@Mag, time is not a 'thing' to be discovered apart from observation; its a means of ordering reality, intrinsic in phenomal reality, yes, but is added by the observer by the process of thought, necessarily. Other mental paradigmns break down as well in qm, because reality in itself does not have the burden of conforming itself within 'thought'.
4 / 5 (1) Feb 04, 2009
Our world may be a giant hologram
From issue 2691 of New Scientist magazine

3.5 / 5 (2) Feb 04, 2009
Sometimes science puts us in a tricky situation.

A theory that may be true, may also be not very useful.

Bear with me for a bit and I will explain. Our brains, being macro-things, like to categorize and simplify to aid understanding ( and thereby, survival ). Anyway, this mechanism is more or less the goal of the brain. When we present a method that shows our world ( universe ) in a wildly different manner than what we perceive, we are reluctant to accept.

Now, I am not saying this theory is right. And I am not saying it is wrong. These are often unimportant distinctions. However, is it useful? Asking that question has real value here.

Knowing what is true and false in the universe is all well and good, and I whole-heartedly support the endevor of knowledge-gaining, but we should not discard theories that are "probably not right" because they still may be useful.

If you still have trouble with what I am getting at, think Netownian physics versus relativity. Yes, relativity is "more correct" but Newtonian is still quite useful, which is why it is still taught.

Anyway, I hope this stimulates some thought.
1.3 / 5 (3) Feb 04, 2009
a theory that may be true, may also be not very useful
Very useful (at least for some people) is the God theory, for example. You can predict nearly everything by using it, it generates money, it may be true and it cannot be refused. What else we should want?

By such approach the science would converge into religious camp very fast. Whereas the whole problem is quite simple: the mainstream science missed the point, environment can be never observed by its own waves. So it claimed negative result of M-M experiment as an ultimate proof of nonexistence of such environment, ignoring successfully all other indicias and particle models of reality.

Is not my problem, I'm not guilty for that mistake - so I'd expect some responsible stance from scientific community and the revalidation of Aether model ASAP. Simply because I'm just not willing to pay research based on trivial mistakes from my taxes anymore. Nobody is prohibited to continue in further research of existing theories - just from private sources, please.

I hope, my stance has certain logics at least for someone.
1.8 / 5 (5) Feb 04, 2009
...relativity is "more correct" but Newtonian...
We are back in times of geocentric model, which was elaborated into high formal precision by thorough fitting with observations. Aether model corresponds the heliocentric model, which appeared counterintuitive and ad-hoced at Galileo times.

We should realize, validity of heliocentric model is based on tautology. It requires a checked gravitational law and known mass of planets at the same moment. But we cannot test one without the another. From pure formal perspective, heliocentric model was never tested by explicit way, as it remains implicit theory.

No wonder, nobody wanted to admit the heliocentric model for Galileo, until independent evidence was found in stellar parallax. From this perspective the Holly Church approach follows the Popper methodology of Mainstream Science very well and nobody can have something against it.

With the only exception, Holly Church has made no mistake in its deductions - whereas Mainstream Science missed the logics of particle environment from its very beginning. By such way, the contemporary scientists are trolling much more by now, then the Holly Church of Galileo era.
3 / 5 (2) Feb 04, 2009
That's not at all what I said. My argument is for usefulness to our understanding. Reading your argument makes me suspect my point was missed.
3 / 5 (2) Feb 04, 2009
Also, either your argument is suffering from a few syntactic/semantic flaws or it makes no sense...
1 / 5 (3) Feb 04, 2009
my argument is for usefulness to our understanding
The utilitarian principle is not testable by its definition. We cannot know, which theory becomes more usefully tomorrow - just because it can help to develop some even more useful theory later.

For example, we can say, the extinction of various species makes no problem for further human evolution: we can synthesize new ones by genetic engineering. But we cannot replace the million years of evolution so easily. What if some extinct strain contains cancer medications, which we are just searching for? Until we cannot travel into past, such lost of information is unrecoverable.
Feb 04, 2009
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Feb 04, 2009
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5 / 5 (1) Feb 04, 2009
What are "gravitation physicians?"
2.3 / 5 (3) Feb 04, 2009
an obstetricians, I presume
2.3 / 5 (3) Feb 04, 2009
The two-dimensional analogy of gravity is well known phenomena noticed in the days of the square rigged sailing ships that, under certain sea conditions, ships lying close together would be mysteriously drawn together until there was a danger of their riggings clashing.


The 3D version of that phenomena coresponds the ancient Fatio-LeSage model of gravity.

This of course may lead into Einstein's utterance that 'I may have got the sign wrong', meaning that gravity is actually a PUSH - and planetary motion calculations do not need their minute fudge factors. Those Fudge factors that physics is so dangerously fond of.
not rated yet Feb 05, 2009
Two dimensional could also be one space dimension and one time dimension.

- Space has (omnidirectional) extension.

- Time has duration. It shows (rate of) change of location of matter in space.

We normally consider space to have three essential extensions in three orthogonal (90 degree) directions, but this is a mathematical convenience only. It does not correspond to physical reality as there are no instances of this 90 degree separation of "spatial dimensions" in nature. They only exist in our mathematical model of reality. Also the terms "one dimensional" and "two dimensional" as used today are nowhere to be found in physical reality. If we talk about reality, we only find that there is extension in space, and that it is equally going in all directions. That is the dimension of space.

Just a thought for consideration...
not rated yet Apr 02, 2009
So much conjecture... Why do so many people make a perfunctory reference to the content before going off on a tangent to explain how things 'really' are? How do they know????

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