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The Plastic Fractal Magnet

bedessen writes "An article at NewsFactor summarizes the developments in new plastics that exhibit magnetic fields of fractal dimensions. Whereas a simple bar magnet produces magnetic fields that go from the north pole to the south pole, the fields of the new hybrid plastic sprout like branches of a cactus lined with secondary fields that resemble needles. As these fields become increasingly interlocked, they exhibit a unique kind of order. This intensely ordered structure might one day be key to storing information with a very high density. The researchers behind this are Arthur Epstein, director of the Center for Materials Research at Ohio State University, and Joel Miller, a professor of chemistry at the University of Utah. There's also this PDF overview of the subject, which is quite technical but still readable."

41 of 161 comments (clear)

  1. If my calculations are correct... by Anonymous Coward · · Score: 5, Funny

    This new fractal magnet will allow my flux-capacitor to send this message BACK IN TIME... to get first post! .....

    Great Scott!

  2. Practical Applications? by kavachameleon · · Score: 5, Interesting

    Is there any news on actual practical applications of these new magnets we've been hearing about? BTW... Discover Magazine had an article on Carbon magnets, quite interesting, because carbon is not *supposed* to be magnetic. Link here. Just my comments...

    1. Re:Practical Applications? by Alsee · · Score: 5, Funny

      Practical Applications?

      Finally! A fractal magnet that will stick to my fractal refrigerator! The normal magnets always fell off because it doesn't have a flat surface.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  3. Less than one dimension is problematic... by dagg · · Score: 5, Interesting
    Controlling nanoscale magnetic fields that exist in less than one dimension may prove problematic...

    Am I the only one having problems understanding that article? I'm not a physicist, but I didn't think anything could exist in less than one dimension. Freaky.

    --
    Sex - Find It
    1. Re:Less than one dimension is problematic... by Jace+of+Fuse! · · Score: 3, Funny

      Controlling nanoscale magnetic fields that exist in less than one dimension may prove problematic...

      I didn't think anything could exist in less than one dimension. Freaky.

      I would say if it can't exist in less than one dimention then controlling a nanoscale magnetic field that doesn't exist would prove QUITE problematic. If they can find a way to get around the whole "not existing" part, this could open up whole new areas of science.

      --

      "Everything you know is wrong. (And stupid.)"

      Moderation Totals: Wrong=2, Stupid=3, Total=5.
    2. Re:Less than one dimension is problematic... by BattleWolf · · Score: 5, Interesting
      Elsewhere in the article it states:

      "A fractal is an object whose volume is not a simple product of its dimensions," Epstein told NewsFactor. Where "the volume of a rectangular box is its length times its width times its height, the volume of a snowflake is a fractal," Epstein explained. Fractal dimensions are fractional -- instead of 3-D or 2-D, they might be 1/2-D or 0.8-D.

      I guess Fractals are freaky... they look kinda cool though... :)

    3. Re:Less than one dimension is problematic... by civilizedINTENSITY · · Score: 4, Informative

      Carbon nanotubes are used to transport single electrons. The wavelength of said electrons are such that the dimensions of the conduit result in what can best be modeled as a one dimensional potential well (as taught in senior-level Intro Quantum classes via ODEs, as a way to avoid the math of 3D potential wells and PDEs). So perhaps it could be said that 1D does exist for very very small, bound objects.

    4. Re:Less than one dimension is problematic... by kasperd · · Score: 5, Interesting

      Anything that can be represented as a (or a finite number of) point could be considered to have a dimension of zero.

      That is true, but in fact you can even have an infinite number of points and still have a dimension of zero.

      There are different kinds of infinity. The set of integers is what we call a countable infinity, while the set of real numbers is what we call an uncountable infinity. There are even uncountable infinites that are infinitely larger than the real numbers. In fact it is a suprprise once you realize how large infinities can become compared to the quite small infinity of the integers. In fact the inifinity of the integers is the smallest infinity you can find.

      A set of countable infinity has dimension zero, anything with dimention larger than zero is an uncountable infinity same size as the real numbers. Wether the dimension is 0.1 or 3.0 the number of points will be exactly the same. And that is the case for any finite number of dimensions. And AFAIK no fractal can be of higher dimension than the space in which it exists, so we can never create fractals with inifinite dimension.

      --

      Do you care about the security of your wireless mouse?
    5. Re:Less than one dimension is problematic... by Henry+V+.009 · · Score: 3, Informative

      You use the one-dimensional potential well because you don't need to take angular momentum into account (which would require the 3-D Schrodinger equation). Think about modeling a baseball in freshman physics. You could do that in 3 dimensions--but you could also beat yourself over the head with a club because it's so much fun when you stop. You model the baseball in 2 dimensions, because that is mathematically equivalent. That doesn't mean that ballistic motion is 2-dimensional.

      Personally, I think the word dimension should be banned from from all discussions of popular science. But hell, there are enough Ph.D.'s out there that shoot thier mouths off like they are unclear on the concept.

  4. Great by FS1 · · Score: 3, Funny

    Something else that i don't understand that will change my life forever.

    --
    A Fatal OE Exception has occurred, Sig will now reboot.
    1. Re:Great by Crusty+Oldman · · Score: 3, Funny
      Something else that i don't understand that will change my life forever.

      Just wait 'till you discover women!

  5. I have a question... by rgoer · · Score: 5, Interesting

    The article, in its initial description of fratal geometry, cited this comparison: where a rectangluar prism has volume of length times width times height , a snowflake has a volume that is fractal in nature. The article went on to say that while the rectangular prism's volume is three-dimensional, the volume of the snowflake, being fractal, was fractionally dimensional (i.e. 1/2d or 0.8d or something, instead of 3d).

    My question: if you were to find a huge snowflake, and melt it down, and measure that water in a graduate, wouldn't you find its volume? And wouldn't that volume be 3d? How does its volume, assuming it remains constant, change from being 1/2d or whatever to 3d? Sorry if I sound ignorant, but fractal mathematics is a little beyond me.

    1. Re:I have a question... by jazir1979 · · Score: 5, Informative

      I'm by no means qualified to answer this, but heck i'm a-gonna do it anyway!

      Yes, the volume of the water would be 3D. The volume changes from 1/2D to 3D because you are changing the geometry of the object! Honestly, I think the answer *is* as simple as that..

      --
      What's your GCNSEQNO?
    2. Re:I have a question... by f97tosc · · Score: 5, Informative

      The snowflake would have a true 3D volume because it is not perfectly thin; it is a physical approximation of a mathematical concept.

      The analogy of the snowflake refers to the edge of the snowflake. Imagine that you took a thread and tried to put it along the edge of the snowflake. Assuming that the thread was very thin it would take an infinitely long thread to cover the entire edge, because of the way it is folded. Thus the 'edge' can be said to have a dimension higher than 1 (it does not fit into one dimension). Using mathematical techniques one can also demonstrate that the the infinite thread takes zero space in 2D, thus the dimension is somewhere between 1 and 2; it is a fractal.

      Tor

    3. Re:I have a question... by civilizedINTENSITY · · Score: 3, Informative

      Fractal implies a geometric pattern that is repeated at every scale and so cannot be represented by classical geometry. While there is a finite volume associated with a snowflake, you are right (I think) in attributing the "fractional" dimensionality of the snowflake to its geometry. Obviously the fractal nature is lost as soon as the flake melts. Consider the question: how doe we determine the volume of the snowflake without destroying its fractal nature? That is to say, what linear measurements of length can be used to calculate its volume? Note: weighing the fractal and using density also avoids the question of a geometric calculation of volume and would be cheating.

    4. Re:I have a question... by boomgopher · · Score: 3, Informative

      I'm a jackass, forgot it was html formatted.

      The dimension D of an object made of N exact copies of itself, each shrunk by a factor of S is:

      log(N)
      ------
      log(1/S)

      So, a fractal is an object with a non-integer D.

      --
      Your hybrid is not saving the environment. Its purpose is to make you feel good about buying something.
    5. Re:I have a question... by gilroy · · Score: 3, Informative
      Blockquoth the poster:

      That is, you've got one three-dimensional liter of water versus one fractionally- dimensional liter of water?

      No, the volume is changed both qualitatively and quantitatively. Even with classical geometry, the volume isn't conserved. Melting an ice cube changes its volume. Why shouldn't melting a snowflake? As has been mentioned, the alteration of the configuration does indeed affect volume.
    6. Re:I have a question... by f97tosc · · Score: 5, Informative

      Imagine that you took a thread and tried to put it along the edge of the snowflake. Assuming that the thread was very thin it would take an infinitely long thread to cover the entire edge, because of the way it is folded

      Isn't this comparable to the Paradox of Achilles and the turtle [openetwork.com]? Meaning that the thread does not have to be infinitely long?
      Well this is a valid but unfortunately rather complicated discussion. When you add an infinite number of objects with size zero (or approaching zero), the sum can turn out to be finite or infinite depending on exactly in what way the objects approach zero size (and sometimes, if I remember correctly, it even depends on the order in which you add them).

      In the case of this 'paradox', you add an infinite number of objects (stretches of time) that approach zero so quickly that the total is actually finite. This is what some of the Greek thinkers did not realize.

      For fractals, on the other hand, when you add the infinite number of small (approaching zero size) objects they end up taking infinite amount of space. This is a necessary condition; if you add them all and the total is finite then it is not a fractal.

      Tor

    7. Re:I have a question... by f97tosc · · Score: 4, Informative

      But doesn't the analogy breakdown because the pattern can't truelly repeat scaling down forever? That is, there will have to come a level at which the resolution of the molecules destroy the ever repeating pattern, like grain in a photograph

      Yes, this is true for all fractals with a physical manifestation. There is always some lower and upper scale where the fractal properties break down. The lower scale is often, as you suggest, on an atomic level.

      A mathematical fractal is an abstraction that has infinite resolution. Such abstractions can be useful to study the properties of physical fractals, even though we know that these are only approximations.

      Tor

    8. Re:I have a question... by jericho4.0 · · Score: 3, Informative
      IANAP, but here goes;
      Everthing you can see or interact with, from snowflakes to magnetic fields, exists in a 3d universe. Such things as electrons, quarks, superstrings etc might not, but I've never seen one.

      The snowflake exibits a fractal dimension over a wide range of scales. If you took a microscope you could magnify it many times over and keep finding the same level of detail being revealed. So we say it has a fractal dimension. Without knowing the fractalness of a paticular snowflake, the dimensions of the snowflake wouldn't be enough to tell you how much water was in it with much accuracy.

      A coastline has the same property on a human scale. As the size of your measuring stick decreses, the length of the coastline increases.

      --
      "A language that doesn't affect the way you think about programming, is not worth knowing" - Alan Perlis
    9. Re:I have a question... by bedessen · · Score: 3, Informative

      A 2D object's area (or "volume" if you will, since there are only two dimensions) changes as x^2 as you scale the object. A 3D object's volume changes as x^3 as you scale the object. An object with fractal dimension has a volume that scales as some non-integer power as you scale the object.

      (additional story link where Epstein confirms this)

  6. Interesting by acehole · · Score: 3, Funny

    I guess the applications for this are pretty big...

    I mean you could have a harddrive that not only gets corrupt when you leave it in the sun (as you do..) but it can melt too.

    --
    Be you Admins? nay, we are but lusers!
  7. Re:Too cold for practical applications... by hdparm · · Score: 3, Funny
    What kind of uses exist for superconductors at these temperatures?

    I don't know but if it's meant to be used for storing information in some kind of computer, that one for sure won't be using AMD processors.

  8. Temperature Issues by limekiller4 · · Score: 5, Interesting

    From the article
    The plastic ultimately stabilized in 1.6 dimensions at a temperature of minus 269 degrees Celsius (minus 452 degrees Fahrenheit).

    It would be nice if someone came up with a chart that plotted the correlation between the temperature necessary in the lab and the temperature necessary to bring the item to market for a significant number of products. Because I'm willing to bet that -249 C is pretty close to the Don't Hold Your Breath mark.

    --
    My .02,
    Limekiller
  9. Getting away from magnetic storage... by silvaran · · Score: 5, Interesting

    I'd like to get away from magnetic storage as a temporary removable storage device... The last time the floor waxer zamboni zipped past my locker I lost my college programming project... not to mention the number of VHS tapes that are useless now... am I alone in this?

  10. Help? by limekiller4 · · Score: 5, Funny

    From the article:
    The plastic ultimately stabilized in 1.6 dimensions at a temperature of minus 269 degrees Celsius (minus 452 degrees Fahrenheit).

    I'd be happy if my girlfriend would stabilize in three dimensions at room temperature.

    How long do you think it'll take for them to figure that one out?

    --
    My .02,
    Limekiller
  11. Plastics, Fractal Magnetics & Optics.. by jamesjw · · Score: 4, Interesting


    It raises an interesting possibility - with a new way of forming high density magnetic fields I wonder if we'll see a return to Megneto Optical media or weather the two will stay seperate..

    It'd certainly be interesting to get more storage out of yer cd sized media if you could use the plastics as a storage medium as well as the optical layer..

    Maybe its a crazy idea..

    Somebody will probably take this idea and ger rich off it none the less :)

    --
    -- If at first you don't succeed, lie!
    1. Re:Plastics, Fractal Magnetics & Optics.. by civilizedINTENSITY · · Score: 5, Informative
      "It'd certainly be interesting to get more storage out of yer cd sized media..."

      Checkout the link in the previous story The Top Ten Physics Highlights of 2002, Highlight #7,Magnets open the gate to nanoscale logic , to see how nano-sized mangetic structures could be used. The hard part is going to be interfacing to this structures. These structures are *small*.
      the ferromagnetic NOT gate is a "completely new class of device" that could be made even smaller. The researchers have also created a 13-bit shift register by linking the devices together, and believe it should be possible to make a full set of logic gates using their technique
      Note: this is digital logic without transistors, but with nanoscale ferromagnetic wire.
  12. Re:FP? by civilizedINTENSITY · · Score: 3, Informative
    Do they even need to get a current flow to generate their magnetism?

    From the pdf link:
    "The essential component of any magnetic material is the presence of an unpaired electron or more precisely, the spin associated with an unpaired electron. These spins, depicted in this article as arrows (a or b), and how they interact with each other determine the magnetic behavior of all magnets. Magnets are materials in which these spins are ordered."
    Perhaps its all about the ordering (which could be due to the geometry of the molecular structure).

    Note: the pdf file also states (towards the end):
    "It is important to emphasize that magnetic ordering is not a property of an isolated molecule; it is a cooperative solid-state (bulk) materials property. Thus, to achieve bulk magnetic behavior for a molecular system, intermolecular interactions must be present in at least two, and preferably three, directions.
    Its interesting that where we are looking at is (I think, perhaps) a non-bulk form of magnetism, and the statement is perhaps overstating a requirement.
  13. Easy intro to fractal dimension by infolib · · Score: 4, Informative

    Is here

    Among other results it is shown that Great Britain's coastline has a fractal dimension of 1.24, while that of South Africa is very nearly 1.

    --
    Any sufficiently advanced libertarian utopia is indistinguishable from government.
  14. A fractal harddrive? by happyhippy · · Score: 3, Interesting
    So doesnt that mean instead of just a single bit being corrupted affecting the one bit, in the fractal drive that bit could affect the rest of the drive?

    Doesnt this therefore introduce the need for a (quantum like) million bits error correction per one bit problem?

  15. So upsetting.... by morganjharvey · · Score: 4, Funny

    I'm so used to coming home from the bars and getting very basic "here's an update to this" or "here's a new apache module" from slashdot.

    But when I come home at 5 in the morning, not quite so sober, and you're talking about half dimensions? That's just not nice.... What the hell am I supposed to wrap my brain around? If it's only half dimensional, does that mean I only have to wrap just my left lobe around it? I'm sooooooo lost.... :)

  16. Poor physics majors by 0x0d0a · · Score: 4, Funny

    They had enough fun with plain ol' obloidish magnetic field calculations. Can you imagine the math once we start throwing in fractals?

    1. Re:Poor physics majors by 0x0d0a · · Score: 3, Interesting

      Sorta. The volume's easier, but I was thinking of what happens if you're trying to figure out how two fields are interacting...

  17. Re:Scandinavian Coast? by infolib · · Score: 3, Informative

    Norway: Fractal dimension 1.52 (here and here, apparently from Feder.)
    Google is your friend

    I suspect the swedish coast has nearly as high a dimension, with Denmark a bit lower.

    --
    Any sufficiently advanced libertarian utopia is indistinguishable from government.
  18. Re:How do you measure 1.6 dimensions? by popmaker · · Score: 3, Insightful

    You find out how the thing works, or evolves. Take a snowflake. You see how it comes to be, you begin with an ice particle, others start hitting it, sticking with it and form a crystal. This is obviously a process which we can set up mathematically. Like, for each iteration, this happens and that adds to the whole snowflake. By using mathematical rules we now use our knowledge of how a snowflake evolves to find its fractal dimension.

    Now, fractals are said to be infinite, that is, they have infinite volume, and a self-similarity on all scales. Natural phenomena does, however, not. So no natural object is a TRUE fractal. But obviously, a snowflake IS self-similar, and it remains self-similar over a number of scales. To be a TRUE fractal it would have to be self-similar infinitely.

    But anyhow, if a object is irregular, and behaves like a fractal, finding it's fractal dimension (or finding the dimension of the mathematical object representing it) is actually quite useful.

    Just think of a fractal as a result of an iterated process. Trees grow leaves. Snowflakes grow, clouds grow, lightnings twist and turn, coastlines get beaten by oceans, etc. The idea of a fractal gives an insight into how such objects come to look like they do.

    and check out my fractal program! :-) fractical

  19. Maxwell by MarkusQ · · Score: 3, Funny

    Whereas a simple bar magnet produces magnetic fields that go from the north pole to the south pole, the fields of the new hybrid plastic sprout like branches of a cactus lined with secondary fields that resemble needles

    Shouldn't the headline have been "Maxwell's equations disproven!" or something else more fitting for such a revolutionary discovery?

    Unless of course Maxwell's equations still stand, in which case the headline should have been something like "Hype replaces progress in science; film at 11:00"

    -- MarkusQ

  20. Fractal dimension... by wirelessbuzzers · · Score: 5, Informative

    If the disjoint union of n disjoint copies of a fractal F makes a similar (in the geometric sense) one k times as big, then the fractal dimension of F is (log n)/(log k) = log base k of n.

    This makes the fractal dimension of a square 2 because it takes four of them to make a square twice as big and log 4 / log 2 = 2. The fractal dimension of the Sierpinski Gasket is log 3 / log 2 because you can assemble 3 copies of it to get one twice as big.

    The dimension of the Cantor set (that's the one where you start with the unit interval and remove the middle third of every line, or equivalently the numbers between 0 and 1, inclusive, whose base-3 expansion contains no 1s) is log 2 / log 3 which is less than 1.

    The dimension of the rational points in a square is still 2, even though it has fewer points than the Cantor set. So, fractal dimensions are "freaky."

    --
    I hereby place the above post in the public domain.
  21. Biological Fractals by Dollyknot · · Score: 3, Informative

    I first learned about chaos theory, from James Gleick's excellent book 'Chaos' about ten years ago. I've been hooked ever since.

    The thing that stuck in my head was Fiegenbaum's number 4.669, which BTW is irrational. This ratio is everywhere and most profound of all, is visible in the architecture of our bodies. The main artery from the heart called the Aorta, is like the trunk of a tree, point being is, if you measure the distance between the heart and the first bifurcation, divide that distance by 4.669, it gives you the statistical length of the two branches from the first bifurcation. Now here is the kicker:- it is that ratio, all the way down to the smallest cappillary, to enable a blood supply for every cell in our bodies.

    GM technology worries me, not because I'm scared of engineering. But because to my knowledge, we do not yet understand the mathematics of morphogenesis. DNA is a simple four bit code and yet somehow or other, nature manages to store a cellular doubling number in that four bit code.

    We all start out as one cell, that doubles in a binary progression. Our body plan is formed by the x,y,z matrics of those doublings. The fractal like architecture of our bodies, gives us a hint to how, the miracle of storing our entire code base, in about four gig might be acomplished.

    This new discovery excites me, who knows where it will lead, a new understanding of life maybe? New math? New electronics? The list is endless.

    Cutting edge indeed.

    Peter

    --
    It's called an elephant's trunk whereas it is in fact, an elephant's nose, a nose by any other name would smell as sweet
  22. Re:How do you measure 1.6 dimensions? by MickLinux · · Score: 3, Interesting

    Okay, here's an interesting project for you:

    (1) Start with the Mandelbrot Set or the Julia Set, calculated to a resolution p (say, granularity of 0.0001.

    (2) Calculate the curvature (curve-centered curvature, not x-axis-centered curvature) as a function of position along the line, down to a resolution of 2p.

    (3) Take the fast-fourier transform of this data

    (4) Use the FFT data to see if you can predict the FFT for lower levels.

    My guess is that it won't be predictable -- but I don't know. It might be.

    BTW... :

    Snowflakes almost definitely aren't fractal. Rather, their development is probably going to be controlled by the semiconducting nature of the outer layer of ice as it freezes, and charges separating as widely as they can.

    Nor are trees fractal. They have their rules, but those rules aren't within the definition of what fractal. Rather, fractals can help one generate convincing images of trees, but the similarity stops there.

    --
    Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's
  23. The CHART by aphor · · Score: 3, Insightful

    Your sig:

    It's much easier to mod me down than to post an intelligent reply.
    That's true only if the opportunities to mod or post are equal. That seems to be true only around 8:30 CST/CDT. Mod and post on the same discussion are prohibited. The opportunity to mod is a rare thing, and it gives the moderator more influence (although with the all-too-easy click-click convenience) than a poster (who can affect the visibility of the thread only at +2 when sufficient karma has been earned).

    I believe the choice to moderate is an important one, and while I agree with your sentiment (I think...) that people who moderate without without knowing what they are doing should think harder about things, I don't think that differentiates moderation from posting replies.

    Oh, which brings me to my point: it's easier to suggest that someone else make(or find) a chart instead of doing it yourself...

    Note: the Slashdot "lameness filter" didn't like my ASCII art, but it apparently ignores journal entries...

    <a ref="http://slashdot.org/~aphor/journal/20520">The chart</a>
    is in my journal. Furthermore, Slashdot doesn't like hrefs from comments to a person's journal. The rules to this Slashdot game are neither simple nor obvious!

    --
    --- Nothing clever here: move along now...