Slashdot Mirror
Holographic Principle Could Apply To Our Universe
New submitter citpyrc sends this news from the Vienna University of Technology: The "holographic principle" asserts that a mathematical description of the universe actually requires one fewer dimension than it seems. What we perceive as three dimensional may just be the image of two dimensional processes on a huge cosmic horizon. Up until now, this principle has only been studied in exotic spaces with negative curvature. This is interesting from a theoretical point of view, but such spaces are quite different from the space in our own universe. Results obtained by scientists at Vienna (abstract) now suggest that the holographic principle even holds in a flat spacetime, like ours.
The holographic universe theory has been around for at least 25+ years
When you have famous astronomers and people such as
* "The stuff of the universe is mind-stuff" - Astronomer Arthur Eddington
* "... our brains mathematically construct hard reality by interpreting frequencies from a dimension transcending time and space. The brain is a hologram, interpreting a holographic universe." - Cyberneticist David Foster
* "Today there is a wide measure of agreement... that the stream of knowledge is heading towards a non-mechanical reality; the universe begins to look more like a great thought than like a great machine" - Astronomer James Jeans
saying the universe appears to function like a holographic mind then I find ANY sort of calculations that can give credence to this theory is definitely interesting.
To most slashdotters it remains only a theory
Table-ized A.I.
Tits exist in at least Four Dimensions.
I've found that over time, they extend their vertical dimension in a much larger proportion than the loss to the original horizontal dimension...
Entropy causes Sagging, film at 11.
Truth isn't Truth - Guliani
The word "theory" implies that it is testable.
In this case it is testable, as there are a couple interferometer based experiments working toward testing it.
But it continues to witlessly push forward on the assumption that the proponents could win the argument (grant money) if it could sell enough books and achieve mainstream popularity.
You don't get a grant for just being popular. You get a grant for proposing to do something, and that something has to both fall under the directives of a particular grant program, and get good reviews about the chances of achieving something and usefulness from other scientists.
I for one don't want to give Physics research a blank check to investigate some unobservable math fantasy.
Like several other new proposed theories in physics, this is not without observation. It is an extension of already seen phenomena and theories. This is in the same way that observations confirming Newtonian mechanics also confirm relativity because it makes the same predictions in the situations tested by older experiments.
The word "theory" implies that it is testable.
"Falsifiable" is a better word here. You don't need to be able to do controlled experiments (tests) in order to have a solid theory - an influx of new observations of the universe as we find it works just as well.
And the holographic principle is certainly falsifiable.
1) It imposes a limit on the amount of entropy in any given volume - find a system which can be in more than the allowed number of states, and isn't inside a black hole, and this theory is dead.
2) It sets a really high value on the entropy of black holes. Black holes become the dominant source of entropy in our universe. This has consequences in cosmology that are fundamental, if the only reason entropy is increasing in our universe is this assigning of entropy to black holes. There are certainly physicists playing with that idea, as it could be career-making, true or false.
3) It has deep implications for the evolution of black holes - how they evaporate. This will be a lot harder to prove (I don't think we'll validate Hawking radiation in my lifetime), but might be possible to falsify by finding a black hole that's clearly not allowed by theory.
Heck, there are implications for particle physics that are still being understood, and lots there is testable now with the LHC. The more and farther you reason from a premise like this, the more likely it is to matter to something easy to measure, or at least possible to measure.
The reason the discovery of the Higgs boson was such a big deal is that it confirmed a bunch of really abstract theory in quantum mechanics that is very, very far from anything we can measure, except at the end of this very long chain of reasoning there's this prediction of this new oddball particle (that there's no other reason to expect - it come from deep in the abstract math of QM, not from anything else we measured). So finding that particle confirms that whole crazy chain of logic. Something similar will eventually happen for the holographic principle.
Socialism: a lie told by totalitarians and believed by fools.
Just about any dimensional space can be represented in fewer dimensions, or even 1 dimension
But that all misses the point here. The point of the holographic principle is not that one can imagine a 3D encoding onto a 2D surface, e.g. a holograph, but that the maximum possible information in a volume is not proportional to volume, but to surface area. That implies the fundamental mechanics of the universe can't be something like "voxels". We observe a universe which we can measure in 3 spatial dimension down to the Plank length, in principle, but that can't be what's really going on, at least if the holographic principle holds.
Socialism: a lie told by totalitarians and believed by fools.
It's all a matter of philosophy. There's been a bit of churning the past few decades, but I prefer this simple differentiation: A theory is a predictive model, an hypothesis is a testable prediction. The utility of a theory is then determined by the success of the hypotheses it generates.
Required reading for internet skeptics
Sure. I don't work in physics, but here is my understanding of the holographic principle.
Imagine that you are in a bathtub. There is a certain kind of physics that dictates the motions of waves in the bathtub. Now, you might believe that you need to understand the entirety of water to predict its future motion. You could develop a theory of water in bathtubs, and run experiments to verify if they are true.
After a lot of thought, you might come across the realization that in order to understand the mechanics of the water in the bathtub, it is only necessary to understand the way the surface of the water moves, or maybe even how the water interacts with the edge of the bathtub. This means that you've reduced the dimension of your theory in some way. While this analogy isn't true, there are examples of where it is-- for instance, the physics of harmonic oscillators, like strings, drumheads, etc, can be understood by looking at the boundaries of those oscillations.
Now, in physics, there are several ways that holography shows up. The most famous of these holography theories is called the AdS/CFT correspondence. It conjectures that a certain 5 dimensional string theory can be understood as a 4 dimensional field theory on the boundary. Now, I think that this perspective is interesting to physicists not because of the dimension change (dimensions in theoretical physics usually have little correlation with the observable dimensions of spacetime) but because it was one of the first known correspondences where a string theory reproduced the results of a field theory. Quantum Field theory is the most validated theory of physics we have, but it is thought to have foundational errors. String theory is suppose to offer a way out, but is... hard.
Hope that helps!
It would seem that ancient wisdom triumphs and we live in a 2D world.