Researchers Store Optical Data In Five Dimensions 239
Al writes "Researchers from Swinburne University of Technology in Victoria, Australia, have developed an optical material capable of storing information in five dimensions. Using three wavelengths and two polarizations of light, the Australian researchers were able to write six different patterns within the same area. The material is made up of layers of gold nanorods suspended in clear plastic that has been spun flat onto a glass substrate and multiple data patterns can be written and read within the same area in the material without interference. The team achieved a storage density of 1.1 terabytes per cubic centimeter by writing data to stacks of 10 nanorod layers."
Five dimensional in the same way... (Score:4, Insightful)
..that my toaster is four dimensional because I can describe it as "silver".
This is cool enough as it is, I don't understand why the technobabble was added: polarization and color information layers may be novel attributes of a disc but there's no real reason to describe them as "5-dimensional" other than to sound physics-y.
Yawn. (Score:5, Insightful)
Misuse of the word "dimension" (Score:4, Insightful)
That's not the same as having six dimensions.
Re:Five dimensional in the same way... (Score:1, Insightful)
In this case they were undoubtedly using dimension in the mathematics sense and not the physics sense.
Also, being able to understand the different meanings of words based on their context is a basic skill of language comprehension. Just saying.
Re:Five dimensional in the same way... (Score:5, Insightful)
To be blunt, your toaster is very much four dimensional if you care about its color.
In ML we talk about feature spaces having hundreds of dimensions and are just being accurate. The things you care about are the dimensions. Want Euclidean dimension in space? There are three dimensions. Dimensionality of spin? One for each of the quantities.
If we want to sound smart, we explain the theory behind SVMs and how it's in an infinite dimensional space:-)
Re:Five dimensional in the same way... (Score:5, Insightful)
It's clear there's a use of the word that's technically fine but it's misrepresentative to pretty much anyone that's going to be reading the BBC article or this Technology Review site or whatever and all sources claim it wasn't the media making it up. It's pretty easy to post here and imply people are idiots because they don't know more than the popular science definition but then again everyone's an idiot about a great many things.
Spinning disks and lasers (Score:2, Insightful)
This should have been tagged "vapor ware". What about the materials involved (gold) ? Re-write ability ? Speed of write ? Speed of reads ? Possible seek times ? How well manufacturing of this scales ? etc.
Re:5 dimensions? (Score:5, Insightful)
1. Building
2. Floor
3. Wing
4. Room
5. Shelf
6. Book
I guess I've been accustomed to thinking about larger dimension numbers than 3 or 4 for a long time.
Re:And.. (Score:0, Insightful)
Seeing that the fourth dimension is TIME just what is the 5h and 6th?
Re:When can I buy it? (Score:2, Insightful)
Re:5 dimensions? (Score:3, Insightful)
You left our its orientation (3D) and it's angular monmentum (3D) (assuming non-point objects). Hence 12-D at least.
Re:And.. (Score:5, Insightful)
There is no "the" anythingth dimension; a dimension is just a property or variable that can be changed independantly of other dimensions within the context. So, in many areas of physics, the four dimensions you use in equations etc will often include time, but that doesn't mean that time is some universal dimension to be found in all equasions. For this storage, when you do the reading/writing is irrelevant to the data, eg, if you write a 1 at 4pm, it will be the same as if you wrote that 1 at 5pm. But, if you write it in a different colour, then the data is different, so, the data at any location can be expressed as a function of the intensity of each of the three colours (or wavelengths) and the intensity of the two different polorizations of light - five dimensions.
If for example you want to talk about the mass of any of the points where data's stored, then what matters is how many atoms there are there, nothing else is relevant, and so you'd only say there's one dimension.
So as you see, dimensions aren't universal things, they're purely contextual.
Re:And.. (Score:2, Insightful)
Re:5 dimensions? (Score:3, Insightful)
In Clifford / Geometric Algebras, which are the correct type of algebras for physics, if there are n dimensions (orthogonal vectors) then there are 2^n degrees of freedom. The grades of the degrees of freedom go by the rows of Pascal's triangle.
For 3-D that is 1 scalar (for real number coefficients), 3 vectors (x,y,z), 3 bivectors (xy, yz, zx - planes of rotation) and 1 pseudoscalar (xyz - volume). (xy = outer product of x and y, often written x^y. x^y = -y^x)
In 4-D space-time: 1 scalar (n) - 4 vectors (x,y,z,t) - 6 bivectors (xy, yz, zx, xt, yt, zt -the latter 3 are velocities revealed as rotations)- 4 trivectors - (xyz, xyt, yzt, zxt - the latter 3 are spins) - 1 pseudoscalar (xyzt). ("t" will have a square (inner product, x^2=x.x) opposite in sign to the other three dimensions, usually t^2=1 x^2=-1.)
Google "geometric algebra tutorial" for more about the physical meaning. It beats the hell out of cross products, quaternions, and many applications of linear algebra and tensors.
Re:And.. (Score:3, Insightful)
mind you, that is no worse than calling stereoscopic pictures or movies "3D". But true 3D is holographic.
Re:And.. (Score:2, Insightful)