## 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."*
## And.. (Score:5, Funny)

... if you add a sixth dimension (time), you can store a near-infinite amount of information!

Retrieval is a bitch though.

## Re:And.. (Score:5, Funny)

My 6th dimensional storage device is /dev/null in order to retrieve the data, all you have to do is go back to the exact moment in time that it was written.

## Re:And.. (Score:5, Funny)

I use the MD5 compression algorithm to store my data. I still haven't found a good MD5 decompressor yet.

## Re: (Score:3, Interesting)

Adisde from the mis-use of the word "dimension", this is not revolutionary.

Magnetic hard disks commonly get 500GB on a much smaller platter. Why is optical so much harder?

## Re: (Score:3, Insightful)

mind you, that is no worse than calling stereoscopic pictures or movies "3D". But true 3D is holographic.

## Re: (Score:2)

## 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,

whenyou 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 dataisdifferent, 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.

## I count 6 dimensions not 5 (Score:3, Interesting)

I was wondering how two polorizations of light were being counted as dimensions, as light still needs a wavelength. Looks like each wavelength can store two bits of information, two patterns (see the photo on the article page), by polorizing it at different angles. So horizontal red is one dimension, verticle red is another; they're both used seperately. Hmm... why are they calling it 5? Am I missing something?

## Re: (Score:2)

And (to reply to myself once more) here's my answer http://hardware.slashdot.org/comments.pl?sid=1239971&cid=28032371 [slashdot.org]

## Re:I count 6 dimensions not 5 (Score:5, Informative)

Hmm... why are they calling it 5? Am I missing something?

Yes - the dimension of the system is just the number of independent variables, the 3 wavelengths and the 2 polorisations.

Think about it in terms of a 1D line vs a 2D plane. In the case of the line there is the less than 0 and greater than 0 regions. When you move up to a plane there are two new greater than 0 and less than 0s (in the y plane as opposed to the x plane of the 1D line, say). So you have 4 possible combinations (or quadrants in the plane) in 2 dimensions.

Also - note that light which is circularly polarised is both vertically polarised *and* horizontally polarised, so you can have unpolarised red light; vertically polarised red light; horizontally polarised red light and vertically and horizontally polarised red light.

(Similar to: just red light; red light and blue light; red light and green light and red light blue light and green light)

## Re: (Score:2)

Yar, I originally read it as dimensions to describe the data read from any physical point, rather than addressing dimensions required to locate the data which is what's meant.

## Re: (Score:2, Informative)

## 5 dimensions? (Score:5, Funny)

x,y,z,strange and charmed?

## Re: (Score:2)

If you had some way to store data in particle spin, I could easily see 6 dimensions.

x,y,z position, plus x,y,z spin.

Interesting stuff....

## Re: (Score:2)

If you had some way to store data in particle spin, I could easily see 6 dimensions.

x,y,z position, plus x,y,z spin.

Interesting stuff....

You should let a physicist know you discovered 3 new dimensions. I think they'd want to know about that.

## Re:5 dimensions? (Score:5, Interesting)

Most physicists should be perfectly comfortable applying the term "dimensions" to cases other than spatial dimensions.

Once you're used to infinite-dimensional Hilbert spaces, media articles that mention "five-dimensional storage" are only infinitesimally interesting by comparison.

## Re: (Score:2)

But you're absolutely correct - physicists (as well as other enlightened and intelligent people) refer to parameters as dimensions.

You need them so that you don't overlap with yourself and become a Bose.

Thumbs up & high five (one for each dimension).

High six if you have an extra finger.

## Re: (Score:2, Funny)

You killed my father! Prepare to die.

## 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:5 dimensions? (Score:5, Informative)

Your example is easy to relate to, but there's a problem people should be aware of. While you can refer to the book's location using a 6-dimensional quantity, you *could* do it in 3, by giving its position in space. In a "real" n-dimensional system, you cannot reduce the system to less than n dimensions.

A good, but less-accessible example, is the state of an object in classical mechanics. The position of an object is 3-dimensional. The state, however, is 6-dimensional: your position (3D) and momentum (3D).

## Re: (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: (Score:2)

Heh. I remember working on a bioinformatics problem for a friend of mine that dealt with no less than

9dimensions. I parsed the data and dumped it into an array that was 9 arrays deep...I'd never done more than 3 dimensions before, and I wasn't even sure it wouldwork. Everyone I showed it to (cs and physics guys) thought it was complete bullshit, but it made the math so hilariously easy...I'm one of those geometry people, so it made sense in my weird brain to apply linear algebra to it.Crazy shit. I had s

## Re: (Score:3, Interesting)

Is that so? Isn't that slightly sloppy, from a physicists point of view?

Rotation and spin are another degree of freedom (and, IRC, has been refered to as such by my physics lecturers), but physically not another dimension.

Mathematically, a Hilbert-space state vector is infinite-dimensional. But physically, it is just a function describing the state of the system in a three dimensional space over time.

My problem with using such an expression in a PopSci article is, that it is sensationalism. It relies on the

## Re: (Score:3, Interesting)

"Rotation and spin are another degree of freedom (and, IRC, has been refered to as such by my physics lecturers), but physically not another dimension"Well they kind of are, in that they can't be collapsed into a smaller number of dimensions. If you take rotation of an object, what that refers to in the lower dimensions is the different in momentum of one side of the object to the other. If you do not include that information, to be able describe the object to the same degree of detail, you'd have to includ

## Re: (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,

## Re:5 dimensions? (Score:4, Informative)

Ya know, reading the actual article (yes, I know) it actually looks like it is 6 dimensions not 5 anyway... as it's 3 wavelengths x 2 polorizations, not 3 wavelengths + 2 polorizations... ie, each colour is used twice, creating 6 virtual colours, ie, 6 dimensions.

## Re: (Score:3, Funny)

## Re: (Score:3, Funny)

## Re:5 dimensions? (Score:5, Funny)

Chuck has as many dimensions as he pleases, and Chuck is not a

theory; Chuck is real. And unlike string theory, he willkillyou.## 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.

## Re: (Score:2)

I don't understand why the technobabble was added

To make people read the story, i.e. to sell newspapers (or ad views).

## Re: (Score:2)

## 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: (Score:2)

His toaster is in fact really four-dimensional. Even in the "usual" sense. It has 3 dimensions of space, and exists for a certain range in the dimension of time.

## Re:Five dimensional in the same way... (Score:4, Interesting)

What about color? What about weight? What about temperature? What about how much Barack Obama likes it on a scale of 1-10 assuming that's defined? All of these are valid features to include in your consideration. Perhaps you only care about two of the spacial dimensions, and it's two-dimensional.

Time is not automatically a 4th dimension. I really wish that myth would disappear. It's a convenience for visualizing some forms of 4D things (eg, imagining a hypercube as a normal cube that is gradually changing size) but you can visualize it other ways as well. I prefer to think of a hypercube as a cube plus its color.

Of course, these researchers are totally exploiting that consideration in the population to get fudning. Kind of like how you always add "with implications to homeland security" to the end of proposals, or "the Reds might already have one" in the good old days.

## Re: (Score:2)

"It has 3 dimensions of space"Even that's not really true. It has three dimensions of space occupied (size), it also has three dimensions of space where it's positioned... so, size and position in a 3 dimensional space requires 6 dimensions. I dunno what you'd use your "fourth dimension" for... it's age perhaps (if we assume it exists now)? If we don't assume it exists now, then you'd need two time dimensions to describe it, one for when it was created and one for when it was destroyed. Of course, four dime

## Re: (Score:2)

What's equally odd is that to the layperson I'm sure 'data encoding using differing polarisations and wavelengths of light' means about as much as 'data encoding in five dimensions'. I guess they decided the latter sounds better.

## Re: (Score:2)

In case the laylifeform* is a retard, then yes. Come on. It was a tech site. We are a tech site. And even if not: Wikipedia is just a bookmark away.

Or don't you learn polarization and wavelengths in early high school (or high school equivalent)?

* Making everything end in "-person" is just p.c. personism. :P

## Re: (Score:2)

Maybe I underestimate people, but I rarely go wrong by assuming low scientific literacy in the general population. Admittedly I didn't RTFA, I just assumed it was the BBC one I'd read earlier in the day, so I was thinking it was aimed at a general audience.

I will, of course, also ensure that I use the -lifeform suffix in future to ensure I don't cause any offence to non-person citizens :)

## Re: (Score:2)

If 5 dimensions is only 5 times as much data stored as usual, then you're right, the term 'attribute' would be more useful.

However, if each dimension compounds upon each other, then it's certainly worth using.

For example, a 5D array of say... 10 bits each (10*10*10*10) for what would usually be only 10 bits for the equivalent 1D would be phenomenal.

## Re: (Score:2)

Can you store a red toaster in the same location as your silver toaster, just because it has a different color?

## Re: (Score:2)

5dimensional.## Re: (Score:2)

## Re:Five dimensional in the same way... (Score:5, Funny)

Oh please, it's as if I said a byte is an 8-dimensional bit.

## Re: (Score:3, Interesting)

A byte is a one-dimensional, eighth-order, array of bits.

Of course, bits in this context are discrete units of information only capable of providing one of two values. This method is interesting because the "bits" are capable of providing 5 pieces of unrelated, non-interfering, pieces of data. It's perfectly acceptable to refer to it as an orthogonal, five-dimensional datum, regardless of the lack of separation in space or time, and that they are not at 90 degree angles.

## Re: (Score:2)

Or you know, it's really just a 3D physical thing in 3D space that they measure various properties of.

Could I make a CD that records data not as pits but as pits painted with color and say I've gotten more dimensions out of it? NO!

## Re: (Score:2)

"Or you know, it's really just a 3D physical thing in 3D space that they measure various properties of"What do you think the 3 dimensions of a physical object are but properties? Is height not a property? Is wavelength of light reflected off something not as important the objects width when describing it? Could you recreate the object exactly with only one of those bits of information?

"Could I make a CD that records data not as pits but as pits painted with color and say I've gotten more dimensions out of i## Re: (Score:2, Informative)

Also, you got it wrong. Their "bits", as you say, are able to store SIX, not five pieces of unrelated, non-interfering, pieces of data. By using three wavelenghts and two polarization, they get to write six different patterns in the disc.

What's happening here is that the coordinates to reach those bits are five: x,y,z,wavelength, polarization. That'

## Re: (Score:2)

Come on, it's a little misleading to claim that this disk is five dimensional. What they mean is that the data storage mechanism has five degrees of freedom.

I might as well claim my fingers are five dimensional, since they have five degrees of freedom too.

## Re: (Score:2)

"I might as well claim my fingers are five dimensional, since they have five degrees of freedom too"They can store information in multiple places in multiple ways at the same time (address 1,1,1,1,1 could store a 1 while address 1,1,1,1,2 could store a 0), whereas your hand can only exist in one state at any one time. The equivalent addressing would be something like a single dimension (finger number) and the value retrieved could be the % at which that finger is extended... so that's five bits of informati

## Re: (Score:2)

## Re: (Score:2)

A bit itself is one dimensional, as it can be two things.

## Re: (Score:2)

A byte *is* an 8-dimensional bit, at least in the mathematical vector sense. Not a particularly useful description of a byte though. And this use of '5 dimensional' is pure marketing bollocks.

## Re: (Score:2)

Is this stored in the same physical footprint of its non-5-dimensional counterpart?

If so, please describe said counterpart, and tell us why it's not 5-dimensional.

## 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.

## What else has gold, glass and plastic? (Score:5, Funny)

Goldschläger! [wikipedia.org]

## Re: (Score:2)

## Yawn. (Score:5, Insightful)

## Re:Yawn. (Score:4, Funny)

FWIW, I would definitely have a geekgasm at a 1 cm^2 TB thumbdrive.

Think about, that's

infinitestorage in a 1 cm^3 bay of thumbdrives.Finally, a hand-held (well, desktop when you consider usage) storage device able to store all the porn ever created in the past OR future.

## Re: (Score:2)

## Re: (Score:2)

## Storage in the Fifth Dimension... (Score:5, Funny)

...can it be the Age of Aquarius?

## Re: (Score:2)

Thank you!

If I had mod points, I'd share 'em.

## Re: (Score:2)

## Misuse of the word "dimension" (Score:4, Insightful)

That's not the same as having six dimensions.

## Re: (Score:2)

Look, my comment has 5 dimensions. Wait a moment... "words"

## Re: (Score:2)

It's not actually misuse of the word "dimension". You're just used to thinking only of spatial dimensions, and other restricted senses of the term.

## Re:Misuse of the word "dimension" (Score:5, Informative)

## Re: (Score:3, Informative)

## Re: (Score:2)

"a 12x12 multiplication table is finite and discrete, but still has two dimensions"Surely they're factors of a single dimension rather than two dimensions?

## Re: (Score:2)

## Ooohhh! Snap!! (Score:5, Funny)

Yeah! take that Sony. They not only have blue ray, they have blue, yellow and green ray.

It's a color laser light-show smackdown!.

Boo-Yeah!!!

## Re: (Score:2)

Which is why Sony refer to it as the sting ray... ouch.

(which I guess would eventually make the blue ray an ex ray?)

## When can I buy it? (Score:2)

I used to read about stuff just like this in Scientific American in ..... 1993.

So where are the products? That's what I want to know. Not bashing on the researchers here, but I will be I 70 before I here there is an actual product I can buy?

## Re: (Score:2, Insightful)

## Re: (Score:2)

## Watch out while storing on the 8th Dimension . . . (Score:2)

. . . you might hit Buckaroo Banzai on the road.

## The hardest part (Score:5, Funny)

is engineering a read/write head which is bent at 90 degrees to reality in two distinct and orthogonal directions.

The downside is that a head crash would threaten the integrity of the space-time continuum worse than a Large Hadron Collider mishap and two

Star Trek: Voyagerepisodes all occurring at the same time.## Re: (Score:3, Funny)

Christ. I mean, having to sit through

oneepisode of ST:V makes me want to destroy the space time continuum. (Yatta!)## Uh, no... (Score:3, Funny)

## Flux Capacitor can't be far, can it... (Score:5, Funny)

1.1TB thanks to optical storage in 5 dimensions...3 more and we'll be driving cars through mountains. I can't wait. I just hope the researchers behind this work realize that no mater where they go, there they are.

## Re: (Score:3, Funny)

## If we remember our 2010 dialog... (Score:2)

Chandra: I've erased all of HAL's memory from the moment the trouble started.

Dr. Vasili Orlov: The 9000 series uses

holographic memoryso chronological erasures would not work.Chandra: I made a tapeworm.

Walter Curnow: You made a what?

Chandra: It's a program that's fed into a system that will hunt down and destroy any desired memories.

## Crap (Score:2)

Crap. Just when I get used to having to work an extra fourth dimensional shift [theonion.com], now I have to pick up work on a 5th dimension?

When will I sleep?

## Re: (Score:2)

"When will I sleep?"By doing things in different places at the same time, rather than different times in the same place - you are asleep already, a few inches to your left.

## 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: (Score:2)

I disagree with your questions (heh) - this isn't a single solution, this is multiple technologies providing multiple solutions. In this instance, they're working together, but they don't have to be. Only by knowing as many different solutions as possible can we be more certain to be picking the best ones.

"Solid state is the future, if I am not mistaken"You may be mistaken... partially... probably. As a replacement for spinning random access media, perhaps, but what about mass distribution where re-writeabi

## Does polarization really count as a dimension? (Score:2, Interesting)

Wavelength is definitely a full dimension, as it would be possible to read data at a near infinite number of specific wavelengths. Reading should be easy because you can just pass the light through a prism and check a specific angle of refraction to find the wavelength you need. Writing would be trickier, but it's an engineering problem that can be improved upon over time.

I'm not sure if I'd call polarization a dimension because there are only two angles you can work with, the angle you start with and the a

## Re: (Score:2)

I'm not sure if I'd call polarization a dimension because there are only two angles you can work with, the angle you start with and the angle perpendicular to it. If you try to use a third angle, data from other two will mix with what you're trying to read. So I would say polarization adds another bit (allowing you to store twice as much), but not another full dimension (potentially allowing you to store orders of magnitude more).

But it's completely independent of the other dimensions, so it probably counts. Maybe this is the same sort of thing as the string theory people mean when they talk about extra "rolled up" dimensions, or how the surface of a sheet of paper and the surface of a paper towel tube are both two dimensional even though there are a lot less discrete positions going around the circumference of the tube?

## Re: (Score:2)

Maybe this is the same sort of thing as the string theory people mean when they talk about extra "rolled up" dimensions, or how the surface of a sheet of paper and the surface of a paper towel tube are both two dimensional even though there are a lot less discrete positions going around the circumference of the tube?I doubt it, the string theorists are talking about SPATIAL dimensions, while this is talking of axis of data stored (the terms fail me, someone earlier had them correct, but my brain failed). I

## Re: (Score:2)

"as it would be possible to read data at a near infinite number of specific wavelengths"A high number perhaps, but light frequency does appear to be quantized, that being the case it's definitely a finite set.

The article that appeared recently about the ultra high speed camera, which works with a single wide spectrum pulse, split through space by prism to interact with the object, with the reflections being recombined to a single point, but seperated through time and read by a single photo diode (or whateve

## Why are the centimeters cubic? (Score:2)

## Meaning (Score:2)

If words meant things, we wouldn't have this argument twice a week. Unfortunately, it's an unenforceable suggestion - people use words as they please.

I prefer to think of this as storing something in three geometric dimensions and two buzzword/marketing dimensions.

As to the time-as-a-dimension thing, was there ever anything so completely wrong? Do things change over time in the second or fourth geometric dimensions? Whoops.

I have to learn to admit to myself that the dimension discussion, like the "what's a

## Polarization can be a dimension, but not wavelengt (Score:5, Informative)

Wavelength doesn't really count as a dimension for stroage, nor can one store an infinite amount of information by using an infinite number of frequencies. However, polarization could be considered a dimension for the purposes of storage.

The problem with anything in the frequency domain is that you cannot encode a single frequency without creating a spread which crosses multiple frequencies. This limits how short a pulse one can encode at the desired frequency and how closely one can pack discrete frequencies together to encode different data. Coupled with the noise floor the combination limits the amount of data which can be stored in the frequency domain.

for example, if you were to look at the fourier transform of a sine wave you would see a single frequency. However, if you were to look at the fourier transform of the sine wave and INCLUDE the lack of a sine wave before and after the sine wave pulse being encoded, you would see a log of bleedover into other frequencies due to the ramp-up and ramp-down times. Any change, such as going from flatline to a sine-wave, will create a lot of harmonics. Harmonics can be reduced (but not eliminated) by using an envelope to ramp-up or ramp-down the operation, but an envelope of course requires the pulse duration to be longer. So the amount of data which can be stored is limited no matter what you do.

It works a bit differently when one is working in a quantum mechanical domain... in that case it is possible to store discrete information at discrete frequencies, but you only have particular frequencies to work with, typically related to the energy level of the electrons being knocked around.

-Matt

## Re:Five? (Score:4, Informative)

X, Y, Z, wavelength, polarization

Just like how a tic-tac-toe board and a chess board are both two dimensional, despite one having a lot more locations than the other, the number of distinct polarizations or wavelengths this can detect doesn't matter. It's the number of different "things" it looks at.

## Re: (Score:3, Informative)

Hard disc platters are made from glass. A cube of glass is very difficult to break, and the surface could be protected with a layer of plastic.

## Not another disk (Score:2)

## Re: (Score:2)

With something like a CCD array? Without movement, you could only read as much data as the CCD could hold, so each disc would be fairly limited in size.

## Re: (Score:2)

## Re: (Score:2)

The two can be equal, in perl.