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More on Lenses with a Negative Index of Refraction
Roland Piquepaille writes "A University of Toronto researcher has developed a flat lens that doesn't respect the "normal" laws of nature and could significantly enhance the resolution of imaged objects. "The creation of an unusual flat lens may finally resolve a long-running controversy about the existence of materials that have metaphysical qualities -- so-called "metamaterials" -- that transcend the laws of nature. The lens could lead to amplified antennas, smaller cell phones and increased data storage on CD-ROMs. As says George Eleftheriades, the Toronto professor, "This is new physics." Check this column for more details and other references to metamaterials."
Maybe it's just me, but every other invention and discovery means, along the other things, smaller cellphones.
"Lisa, in this house, we follow the laws of thermodynamics!"
01101001 01100001 01101101 01101110 01101111 01110100 01100001 01101100 01100001 01110111 01111001 01100101 01110010
The University of Toronto has an article about this.
"I'd rather have a full bottle in front of me than a full frontal lobotomy"
It is impossible to transcend the laws of nature. You can only determine that your understanding of nature has changed.
Nick Powers
Encryption: I may not agree with what you say, but I will defend your right to encrypt it...
I read the summary and terms like 'predicted analytically and demonstrated through simulation' don't seem to indicate that the material is actually developed. Unfortunately I don't have a subscription so I couldn't delve further. Anyone care to see if this is just speculation or if they actually have a material that seems to have neg refractive-index properties.
Now you can finally quit your job at 7-11 and start earning a decent income applying all of the metaphysics you studied in college in the new field of metamaterials!
New technology does not equal 'metaphysical' devices. That's a stupid and confusing use of the word. And do you really mean to tell me that anything which isn't completely understood 'violates the known laws of physics'? Take a valium.
'Metamaterials" are not "metaphysical", in the same way that metainformation is not inherently metaphysical. Meta is--say it with me people--just a prefix meaning (from the jargon file) "one level up" or if you prefer (from websters) "between, with, after, behind, over, about, reversely".
Metamaterials are carefully constructed arrangements of regular materials, whose properties combine to produce behaviours that no "pure" material can duplicate, including negative indexes of refraction.
This should not be a surprising concept to anyone who is aware that, for example, atoms can combine form metatoms (so-called "molecules") that have all kinds of properties not found when dealing with pure elements -- and yet the laws of nature survive!
There is no transcending the laws of nature going on here.
"Just once, I'd like to meet an alien menace that wasn't immune to bullets." -- The Brigadier, Dr. Who
The emphasis on the "flatness" of the lenses, at least on /., is misguided too. These are special materials, and the lenses are flat because they have to be owing to the properties of the materials, not the other way around.
Heck, there are all different shapes of lens. Nikon's been out front with consumer "aspherical" lenses for a few years now, selling them in camera lenses and relatively low-end consumer binoculars. They let you simplify things like the number of elements in a camera lens, or help with distortions on the edge of the field in binoculars. Those are all curved, still, just not spherical on the edges -- but a new shape of lens isn't really much news. It's the whacky materials that make this story.
I guess it's science reporting, so let's take what we can get.
/shrug
"Fundamentalism" isn't about divine morality. It's about human authority.
The original UToronto release talks about evanescent waves, apparently a fairly critical part of the equation, and leads to the conclusion that the laws of physics are not actually being broken. Rather, the whole idea is that it is possible to create a lens with a negative index of refraction without anything exceeding the speed of light. Fancy footwork, yes, and perhaps still only a theoretical possibility rather than product nearly ready for sale. But not quite as dramatic as it sounds.
I hate it when science discoveries are reported in that uber-hyped style. It so obscures what the real finding actually is. It looks like they have something here, but in between the whole 'transcend the laws of nature' garbage and the 'this is so fantastic and revolutionary it will change absolutely everything' garbage, it's hard to see what they actually have.
Need a Python, C++, Unix, Linux develop
The U o T press release with a bit more info can be found here.
-PCB
'Men never commit evil so fully and joyfully as when they do it for religious convictions.' B. Pascal
Anyone that has had a high school physics class or a few semesters of introductory physics in college remembers snell's law and that infernal little quantity called 'n' that describes the characteristics of the material with respect to light. What they don't tell you in those classes is that you aren't even getting half of the picture.
Initially, you see n defined as c/v, where v is the speed of light in the material. Since v is less than c (always) this number is always greater than 1 except for vacuum. This is where the 'wierd science' part comes is, and the fact that you're only getting a fraction of the picture. In reality, n has both real and imaginary parts - the imaginary part decribes the 'folding' or how much the wave magnitude decays in the medium over distance and time. For example, if you took something that measured the intensity of light outside in the sunlight and compared it to the intensity of light behind a window in a house, the intensity *inside* would be less because the glass absorbs a certain amount of energy of the light as it passes through. As you can see, this 'n' thing is a little more complicated than what you learned initially in high school and college - end result, well, they sorta lied to you. In fact, the above is just scraping the barrel because you're still trying to give physical credence to a mathematical model.
The 'bad science' comes from putting too much faith in what the math really means. Guys, math is just a tool to *model* reality. If you put too much credence in it you start to think that stuff like virtual particles and feynman diagrams are real. They aren't. They're a tool used by physicists to get an answer that agrees with experiment. For more info on negative index of refraction stuff look at what these guys did, and also look here for a little more info.
Not that it isn't cool to hope that things go faster than light and that we're just getting part of the picture...
Did you lose it in some metaphysical device?
The term 'metaphysical' is only used in the title and first line of the article. The scientists all use the term 'metamaterials' instead. A better definition of what 'metamaterials' are:
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As a matter of fact, I am a lawyer. But I play an actor on TV.
For those scratching their heads at this one, maybe I can help. (I'm not an expert in this field, but I do related work).
First off, the article mentions three properties: permittivity, permeability and refractive index. To keep the discussion simple, lets only consider refractive index, which is negative here.
So what does that mean? It in some sense it means that light is traveling backward in such a material. Not in the reflected sense of backward, but in the time reversal sense. For example, lets say you have light from a light bulb incident on such a material. In air, the light is divergerging (spreading out) from the light bulb. When the light enters this material, it no longer is diverging, but it is instead now converging.
It's certainly not hard to think of a different way of making light converge: use a lens. Indeed, at first glance a material with a negative index of refraction would seem to act very much like a lens. However there are some important differences.
In particular, lets say you wanted to make a very small spot of light (useful for reading CD's, or making IC's). A lens can at best focus light down to a spot roughly equal to the size of the wavelength of light. (This is why blue lasers are wanted for advanced CD/DVD's: shorter wavelength gives a smaller spot which gives greater density). A material with a negative index can get around this limitation.
How? There is one conventional way of making a spot of light smaller than the wavelength. That's by simply using a pinhole (or a capillary, which is esentially a pinhole with a funnel to push more light through pinhole). The problem with a pinhole, is the small spot of light only exists in the plane of the pinole. The light diverges very quickly so it's hard to do anything useful with it. (There is some interest in doing near field microscopy this way). However, if you had some of this magic material, you could recreate the small spot in a different plane. (You can't do this with a lense because it is impossible to capture the entire wavefront exiting the pinhole. This material has no such limitation - you can put this material right up against the pinhole).
This explains why this material might be interesting for CD technology. I have no idea about the other applications they mention.
I'm sure this lenses is real, but the submitter is hopelessly confused about the laws of nature and metaphysics. For one thing, metaphysics doesn't really have much to do with real physics at all, but rather refers to thinking about the nature of reality. Questions like "does god exist", "What makes something 'true'", "how can paradoxes exit" etc. Something that violates the laws of nature is supernatural.
And secondly, nothing can violate the laws of physics anyway. If something can't be explained by physics, then it means our theories are wrong, not the thing is 'supernatural' or whatever. Geez.
And to think, my great post about using enzymes to create electricity rather then expensive fuel cells got deleted.
autopr0n is like, down and stuff.
Actually, my BS detector went off in a few places in the linked article.
"Light passing through a flat glass lens will diverge." Not on my planet, bucko.
"'allows focusing almost two orders of magnitude higher than is possible with conventional lenses'..." Exactly what numerical quantity corresponds with "focusing?"
"the amount of information that could be stored on optical media would be vastly increased..." I thought that was limited by the wavelength of light used to record and read the information.
"By reversing the mathematical signs of the three main properties of all optical materials -- permittivity, permeability and refractive index -- Veselago showed that light going one way in normal materials would reverse direction in metamaterials." 1) Sure, if I start flipping signs in long-accepted equations that describe phenomena in the natural world, I can come up with all kinds of breakthroughs - antigravity, to say the least! 2) But if I set up a conventional refractive/reflective (I specifically omit "diffractive") optical system of any sort, can't I also run the light the other way identically?
Now, I think I recall an article in Scientific American some time back about structures made up of nanoantennae whose macroscopic optical properties were counterintuitive, but I don't think what I'm reading here speaks to that.
...and Physicists are terrible at English. Seriously guys, put down the calculator and look up some of the words you are using; you are starting to sound like Dubya (He misunderestimated my mathematical abilities!). Once they start reporting that "the discovery filled me with shock and awe and sent me into a regime of extreme delight" I'm gonna start waving a gun around. :-)
Seriously though, just because Joe Physics "proved" something with a number of complex mathematical conjectures and theories 20 years ago, that doesn't mean that all future results that contradict this are "violations of the fundamental properties of Nature". Please get down off your high horse. The universe was not created according to a first-year calculus textbook, and if you disagree with this you have your own regime...sorry...agenda to push, such as having a commonly-accepted theory with your name on it.
Reminds me of a graph published by a fairly respected researcher that one of my profs showed me that modeled the spectroscopic properties of a number of compounds to a tee. A whole lot of work went into this equation, and it was even more impressive when you consider the limited processing power of computers at the time. There was just one catch: the modeling equation had FIVE variables...oh sorry..."correction factors". My friend asked him if they tried fitting the properties of a cup of coffee to the graph as well, because it would probably fit with the proper "correction factors". He thought it was worth a try...but he IS a coffee nut.
One organization makes a robotically controlled radiation delivery "laser" that does effectively that by continuously moving around your body: It aims at the tumor constantly, but only spends a very small percentage of time on any other area of the body, hence the total radiation to the tumor is very high, while the destruction of healthy cells is limited.
Hearing about that product I imagine that that is a really cool and noble software development pursuit.
I've noticed in the last few months that Slashdot's science coverage is going downhill. Good things go unmentioned, while crap like 'metaphysical' materials gets posted. Better refresh. Probably got a new story up about free energy or time travel. Or maybe one about creationism being correct, while we're at it.
For her Lasik is getting within reach, but still carries a significant risk of further loss of vision and is unlikely to get her eyesight to the point where she don't need glasses.
Glasses is going to remain the only safe option for a lot of people for years to come.
metamaterials.net
From this articleIf you want to go beyond the media, then you might want to check out the papers by George V. Eleftheriades. BTW the article has a bad URL for the University of Toronto, is should be http://www.utoronto.ca.
Jumpstart the tartan drive.