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Though diamond isn't as good a semi-conductor material as silicon due to a wider band-gap (>3eV compared to silicon's 1.12eV), it can be successfully n- and p-doped to form p-n junctions and FETs with (iirc) enough gain for logic applications.

See here for further detail.

You're right in saying that zero-temperature, un-doped diamond is an insulator, but then so is zero-temperature un-doped silicon.

There are several groups working on competing approaches. There are two groups in the US (disclaimer: I work for one) and one in Germany working on the epitetinal electrical stimulation approach; one US group working on a subretinal light-powered device; one US group working on an approach involving light-activated neurotransmitter chemicals, one group in Belgium using an optic nerve "cuff" electrode; a group using cortical stimulation (the main subject of the Wired article); and probably others, not to mention all the work being done on stem cell transplants.

Some of the latest research results in the area have been collected in an issue of the Journal of Neuroengineering.

One-fifth of an atmosphere is a vacuum? That's pretty high pressure if you ask me. Most modern areas of science need much much lower pressures than that to be viable (10^-3 torr at the very least).

But, hey, isn't it *fun* to know that there are some cheap (tabletop) experiments that are still out there waiting to be done?

Many of the really good cheap science has been done already, but that isn't to say that it's all used up! You could always win an Ig noble by studying beer froth

Yes you can, but the moon is about 2100 miles across

Even the best laser will disperse to a spot a few miles across on the moon. When it hits there, it needs to be bright enough to be visible here. and it needs to be much larger.

Imagine the moon as a circle 2100 pixels across. For the writing to be visible on earth, the illuminated line probably needs to be 25 to 50 miles across. And bright enough to shine back 235,000 miles. Mind you, the moon is about the size of your thumbnail when you hold your hand out in front of you. Think something with the resolution of a 48 pixel icon file, maybe less.

The proportions are easy enough to figure out. Then we get to the power requirements of such a beam.

Typical entertainment grade lasers for light shows are 5 - 20 watts, and can be higher power. If you want a spot 6 kilometers wide on the moon, then normal 6 mm wide beams (about 1/4) would have to expand 1,000 times the diameter, 1,000,000 times the area, and would have to be about 40 megawatts. 6 KM = 3.728 miles.

If you want a 60km spot then you are taking about 10 the diameter, another 100x the area, and so 100x the power for the dot to scale properly.

This means a 4 gigawatt laser to draw your pretty design on the surface of the moon. You could probaly get away with a simple Gigawatt laser. The only ones currently made are scientific research grade, and generate pulses in the nanosecond range. a 10 gigawatt laser to push a solar sail as a means of interpalnetary propulsion. There is also this interesting paper.

No offense mate, but you're off your rocker.

There *was* a beginning to the universe, it is widely accepted that the universe is 'the ultimate free lunch,' and was brought into existence by a quantum fluctuation. Not only that, but we have a pretty good picture of what happened during the first 3 minutes, as well as what happened after that.

As any astronomer would explain to you, there is a point which we could call the end of the universe, depending on who you believe about when the universe will end. I'm speaking of the two possible eventual outcomes for our universe: Heat Death or collapse. (Although at this point the majority of cosmologists agree that our universe is expanding at an accelerating pace, and thus the universe is doomed to become a very chilly place indeed).

"But how," you ask, "can you claim that heat death is the end of the universe, or of time?" Sure, time will go on after heat death, but there will be nothing around to MEASURE that time, because all activity in the universe will have stopped with the temperature at a very cold 0K.

I also found it a bit funny that you think we need a new Galileo or Copernicus, when we have someone even better. Weinberg is one of the most brilliant physicists that has ever lived, certainly the most influential of my life (if that gives you a clue to how old I am). Don't get me wrong, I'm not trying to belittle Copernicus, Galileo, Newton or even Einstein. But Weinberg came up with a theory to unify two of the four fundamental forces (weak and electromagnetic), as well as the Inflationary theory.

Now, as far as escaping our universe and getting to another universe, this is all highly theoretical stuff. But there are a fair number of scientists who believe that our universe is but one in a larger multiverse. There are numerous theories about how these other universes would be formed, as well as how they could be kept seperate from our own which I will not go into here (some involve black holes, others involve the period of unknown time immediately (picoseconds) after the Big Bang.

"The Big Bang theory isn't about beliefs as you seem to use the word. It's about the best explanation that fits the evidence."

It is perhaps the best CURRENT explanation. But it is not as good a theory as it was even a few years ago. There are questions that the Big Bang theory has no explanation for.

For example, as recently as 1998 it was discovered that the universe is "flat". A tiny difference in the density of the universe, either up or down, would make it curved. This means the Big Bang was "tuned" to produce exactly this density. The odds of that happening by chance are estimated at 1 to 10^50.

The Big Bang does not explain the increasing evidence that the expansion of the universe is actually accelerating .

The Big Bang theory does not adequately explain (IMHO) the "Horizon Problem", which is that the universe looks uniform in all directions, from galaxy evolution to background radiation. (Yes, I am aware of "Inflation Theory", which seeks to address the Horizon Problem, but it's pretty shaky. Here's a paper disputing the ability of the inflationary model to produce homogenous CMBR if you are interested.)

Dead-Tree References:
"The Field", Lynne McTaggart - Recommended for everyone, written for laymen.
"Science and the Akashic Field", Ervin Laszlo - This is a bit more technical.

Enrico Fermi supposedly failed every single person who ever took his Quantum Mechanics course at the University of Chicago.

This story is not likely.

Fermi only gave the quantium mechanics course once in 1954 in the last year of his life. He was known as an outstanding teacher, always willing to help students. His notes for the course were published in a book titled Notes on Quantum Mechanics with additional material supplied by one of the students. None of the reviews I've found mention the story about all the students failing.

One of his colleagues writes:

Fermi's legendary classroom teaching was the fruit of careful preparation. He seemed to derive pleasure from the act of teaching, without regard for the result. He never showed annoyance at a student's failure to grasp on the first try (or even the second) what he was trying to explain. On the contrary, if Fermi had to repeat an explanation, his pleasure appeared to be doubled.

Laser-triggered lightning discharge and it's done by *GASP* non-Americans! Guess we have to vaporize Malaysia as soon as their chip fabs get too old to be useful...

Mal-2

It seems you are trying to make a semantical argument about this. So don't just take my word for it, see what the Institute of Physics have to say about it as well.

So far, analog neuromorphic VLSI has hit a dead-end in terms of real applications. Also digital signal processing has been speeding up to the point where it can go almost as fast as a lot of the parallel analog models.

The one exception is that the work on analog retina models lead to the development of the Foveon X3 technology, which is just packing R,G, and B CMOS sensors into a single vertical column on a chip. But again, the neuromorphic part of the retina model is not the X3 technology, the X3 technology is stacking CMOS sensors.

Analog neuromorphic VLSI did have one big result, the electrical engineers managed to teach the biologists a lot about signal processing, and the cross-pollination of this knowledge has lead to discoveries such as ripple analysis in auditory cortex.

Check out Table 1 and Table 3 - "liquid ink pen" has 6/6 success rate.

3D Holograms Detect Fake Signatures

Several sources reported last week that a new technique that produces 3D holograms of handwriting could be used to detect fake signatures on checks, credit card receipts or other important handwritten documents. Here are pointers to Nature , Scientific American or BBC News Online . Instead of using 2D techniques to look at the sequence of pen strokes in a signature, this new method is based on 3D micro-profilometry which permits to translate the writing into an image showing dips and furrows of the sample so that anomalies can be detected. If you plan to imitate your spouse's signature, beware! Forensics have a new and very efficient tool. As an example, for the use of ballpoint pens on normal paper, the success rate was 100%.

Nature describes the problem and its solution.

Suspect signatures are usually analysed by expert graphologists, who compare the appearance of different letters in a name with a verified original. However, they are restricted to looking at flat, two-dimensional writing, and good forgeries can sometimes slip through the net.

The new three-dimensional analysis reveals the sequence in which each pen stroke was made on the page. The technique also highlights differences in the pressure applied by the writer as they marked the page. Such pressure differences are extremely difficult to mimic.

Let's turn to BBC News for more details.

Conventionally, handwriting has been analysed by forensic experts in 2D, looking at the sequence of pen strokes in handwriting, like a signature.

But this is not entirely accurate, because the exact sequence of strokes is not always clear and can vary.

"Using virtual reality and image processing, it is possible solve two of the most difficult problems in graphology: strokes superposing and strokes direction.

"These, in particular in case of same inks, are not detectable in a objective way with the traditional methods," Lorenzo Cozzella, part of the research team, told BBC News Online.

Here is a an example of "profilometric acquisition by means of conoscopic holography. These strokes were made by a BIC pen on common paper. The investigation area is about 5 mm × 5 mm. (a) 3D view of the strokes' profile. It is possible to note the regularity in the (S) line. (b) 3D view of the strokes' profile. The presence of bumps is evident. (c) 3D view with a mirror along the z-axis."

The research work has been published by the Journal of Optics A: Pure and Applied Optics in its Septemebr issue under the name "Superposed strokes analysis by conoscopic holography as an aid for a handwriting expert." Here are two links to the abstract and the full paper (free registration needed, valid for 30 days, PDF format, 6 pages, 320 KB). The above images come from this paper.

How is this technique working? Surprisingly well, according to Nature.

To test their system, the scientists used a database of 126 letters, each written by a different author. In almost 90% of the cases they tested, the author of a particular letter could be identified by comparing details of how their pen strokes crossed with a set of verified writing samples. For ballpoint pens on normal paper, the success rate was 100%.

If you want to see the

3D Holograms Detect Fake Signatures

Several sources reported last week that a new technique that produces 3D holograms of handwriting could be used to detect fake signatures on checks, credit card receipts or other important handwritten documents. Here are pointers to Nature , Scientific American or BBC News Online . Instead of using 2D techniques to look at the sequence of pen strokes in a signature, this new method is based on 3D micro-profilometry which permits to translate the writing into an image showing dips and furrows of the sample so that anomalies can be detected. If you plan to imitate your spouse's signature, beware! Forensics have a new and very efficient tool. As an example, for the use of ballpoint pens on normal paper, the success rate was 100%.

Nature describes the problem and its solution.

Suspect signatures are usually analysed by expert graphologists, who compare the appearance of different letters in a name with a verified original. However, they are restricted to looking at flat, two-dimensional writing, and good forgeries can sometimes slip through the net.

The new three-dimensional analysis reveals the sequence in which each pen stroke was made on the page. The technique also highlights differences in the pressure applied by the writer as they marked the page. Such pressure differences are extremely difficult to mimic.

Let's turn to BBC News for more details.

Conventionally, handwriting has been analysed by forensic experts in 2D, looking at the sequence of pen strokes in handwriting, like a signature.

But this is not entirely accurate, because the exact sequence of strokes is not always clear and can vary.

"Using virtual reality and image processing, it is possible solve two of the most difficult problems in graphology: strokes superposing and strokes direction.

"These, in particular in case of same inks, are not detectable in a objective way with the traditional methods," Lorenzo Cozzella, part of the research team, told BBC News Online.

Here is a an example of "profilometric acquisition by means of conoscopic holography. These strokes were made by a BIC pen on common paper. The investigation area is about 5 mm × 5 mm. (a) 3D view of the strokes' profile. It is possible to note the regularity in the (S) line. (b) 3D view of the strokes' profile. The presence of bumps is evident. (c) 3D view with a mirror along the z-axis."

The research work has been published by the Journal of Optics A: Pure and Applied Optics in its Septemebr issue under the name "Superposed strokes analysis by conoscopic holography as an aid for a handwriting expert." Here are two links to the abstract and the full paper (free registration needed, valid for 30 days, PDF format, 6 pages, 320 KB). The above images come from this paper.

How is this technique working? Surprisingly well, according to Nature.

To test their system, the scientists used a database of 126 letters, each written by a different author. In almost 90% of the cases they tested, the author of a particular letter could be identified by comparing details of how their pen strokes crossed with a set of verified writing samples. For ballpoint pens on normal paper, the success rate was 100%.

If you want to see the

Abstract

For legal purposes there is a requirement for the validation of signatures and handwritten documents. A helpful method in this respect is the so-called superposed strokes analysis, based on the observation of some characteristics in the writing, such as some letters and their dynamics.

This paper introduces a promising new technique for superposed strokes analysis based on conoscopic holography. Through a non-contact 3D measure a 3D profile is created of the superposed strokes that allows the writing dynamics to be determined, such as, for example, if a stroke was drawn clockwise or counterclockwise.

We propose a 3D analysis by an opto-electronic system, in order to improve the graphology analysis for off-line signature verification.

"In relativistic electromagnetism the recoil force of a railgun should act on the magnetic field and absorb field energy-momentum. The Ampere-Neumann electrodynamics, on the other hand, requires the recoil forces to reside in the railheads and push the rails back toward the gun breach. Experiment confirms the latter mechanism."

Railgun Recoil and Relativity
(the above is actually the whole article)

As far as Newton is concerned, yep. It would have to bolted to the deck pretty tightly.

Here's a very short description: Railgun recoil and relativity

Drexler *never* said that "grey goo" would consume the biosphere. What he actually said was "Dangerous replicators could easily be too tough, small, and rapidly spreading to stop - at least if we made no preparation." (emphasis mine, see Engines of Creation Chapter 11). It has been known for more than a decade that there are easy solutions to the problem of designing "safe" replicators that do not grow exponentially using strategies such as the "broadcast architecture" (in computer science terms -- you never give a replicator a copy of its own source code). [See Merkle, R. C., "Self Replicating Systems and Molecular Manufacturing", JBIS 45:407-413 (1992)].

Nor is the idea that assembly lines produce better manufacturing systems than self-replicating systems new. [See Hall, J. S., "Architectural considerations for self-replicating manufacturing systems", Nanotechnology 10(3):323-330 (September, 1999).] It is obvious that the ability to self-replicate is extra overhead when compared with assembly systems optimized for specific assembly tasks.

Finally, it was shown several years ago that we have the technology to detect out-of-control self-replicating systems (nanorobots generate heat which can be detected by existing satellite systems). [For a discussion of various scenarios read: Freitas, R. A., "Some Limits to Global Ecophagy by Biovorous Nanoreplicators with Public Policy Recommendations" (May, 2000).]

Drexler alludes to the fact that we are already in the midst of a "green goo" ("We have trouble enough controlling viruses and fruit flies.") Most people are unaware of the fact that they have more copies of foreign genomes (in the form of self-replicating bacteria) on or in their body than they have copies of their own genome. Some of these bacteria actually produce vitamins that humans use. So "goo" scenarios should not be viewed as completely negative. It is worth noting that the same methods that can be used to stop the "green goo" (e.g. heat or radiation) can be used to stop the "gray goo" if we are prepared to detect and eliminate it. One sees examples of this today as government agents circulate through the crowd waiting to view President Regan's body in Washington with biological and chemical weapons detectors. It simply comes down to understanding the hazards and being prepared to deal with them.

It is also worth noting that the design of fully self-replicating nanorobots is *not* a simple or inexpensive task. (Look at how long it took Nature to get it started...) So it is highly improbable that such abilities could be developed by rogue groups before civilized nations developed robust detection and elimination methods.

For people who want to read more details, the IOP press release is here and points to the actual paper (registration probably required).

Also, I would respectfully request before you post any responses to this note that you "go do your homework" (that will put you one up on the reporters reporting on this and allow for an informed discussion).

Drexler *never* said that "grey goo" would consume the biosphere. What he actually said was "Dangerous replicators could easily be too tough, small, and rapidly spreading to stop - at least if we made no preparation." (emphasis mine, see Engines of Creation Chapter 11). It has been known for more than a decade that there are easy solutions to the problem of designing "safe" replicators that do not grow exponentially using strategies such as the "broadcast architecture" (in computer science terms -- you never give a replicator a copy of its own source code). [See Merkle, R. C., "Self Replicating Systems and Molecular Manufacturing", JBIS 45:407-413 (1992)].

Nor is the idea that assembly lines produce better manufacturing systems than self-replicating systems new. [See Hall, J. S., "Architectural considerations for self-replicating manufacturing systems", Nanotechnology 10(3):323-330 (September, 1999).] It is obvious that the ability to self-replicate is extra overhead when compared with assembly systems optimized for specific assembly tasks.

Finally, it was shown several years ago that we have the technology to detect out-of-control self-replicating systems (nanorobots generate heat which can be detected by existing satellite systems). [For a discussion of various scenarios read: Freitas, R. A., "Some Limits to Global Ecophagy by Biovorous Nanoreplicators with Public Policy Recommendations" (May, 2000).]

Drexler alludes to the fact that we are already in the midst of a "green goo" ("We have trouble enough controlling viruses and fruit flies.") Most people are unaware of the fact that they have more copies of foreign genomes (in the form of self-replicating bacteria) on or in their body than they have copies of their own genome. Some of these bacteria actually produce vitamins that humans use. So "goo" scenarios should not be viewed as completely negative. It is worth noting that the same methods that can be used to stop the "green goo" (e.g. heat or radiation) can be used to stop the "gray goo" if we are prepared to detect and eliminate it. One sees examples of this today as government agents circulate through the crowd waiting to view President Regan's body in Washington with biological and chemical weapons detectors. It simply comes down to understanding the hazards and being prepared to deal with them.

It is also worth noting that the design of fully self-replicating nanorobots is *not* a simple or inexpensive task. (Look at how long it took Nature to get it started...) So it is highly improbable that such abilities could be developed by rogue groups before civilized nations developed robust detection and elimination methods.

For people who want to read more details, the IOP press release is here and points to the actual paper (registration probably required).

Also, I would respectfully request before you post any responses to this note that you "go do your homework" (that will put you one up on the reporters reporting on this and allow for an informed discussion).

True, but the editors (i.e. referees) are not just commenting on the style of presentation but on the content and methodology. They should have a mastery of the subject and be fully appraised of the state-of-the-art so that journal content is properly peer reviewed.

The "vanity press" argument is flawed. Journals do not have very high readerships - they appeal to very specialised communities - and thus they do not have access to the economies of scale of traditional publishing. It's not that there isn't demand - it's just not substantial compared to say, mens' magazines.

The advent of electronic publishing reduces the burden so that the costs are smaller and largely fixed irrespective of demand. This means that journals can be run by professional societies who can permit their members to publish at no cost.

Check out The Institute of Physics and its journals. They allow free 30 day access.

Then you've heard of the Institute of Physics' Dirac Prize, right?

Not to mention this other canny Brit.

Ethanol is a lot easier to transport, refill,... than hydrogen. I bet a lot of energy is wasted in the ethanol->hydrogen reaction. So why not just use the ethanol directly?

Because this system is using low-grade ethanol that has a lot of water in it. Engine-grade ethanol has to have the water removed, the process is much less efficient. Institute of Physics article.

Ethanol takes energy to make. Lots of energy

This article says that one advantage is that you don't have to remove all the water from the ethanol for this process to work. The final stage of removing the last few percent of water does use quite a bit of energy. So I wonder how this difference would change the math on this. Also if the equipment using this device goes from 20% efficiency to 60%, that could mean if this technology became widespread (used by the tractors and trucks growing and hauling the grain) This would mean that growing and hauling the grain would be far more energy efficient. I wonder if this could make ethanol actually become a significant source of energy. I'm not saying this will all happen but it sure would be exciting if the math works out for this scenario.

The IOP web site here claims that ethanol to electricity is 3x more efficient than ethanol for powering vehicle engines.

One item of interest is that this new technique converts ethanol to hydrogen at a 60% efficiency rate, compared to the 20% efficiency rate with current technology.

This article gives a few more details, and here is the actual press release.

Just go here.

from the Institute of Physics

I read the actual paper, (available, with registration required, here), and granted, these guys did a good job on the analysis and experimental verfication, and also should be commended for bringing attention to this phonemena, but the basis for their work has been know for quite some time. In the field of geophysics, it has long been known that "spontaneous potential" exists due to the flow of water through sermipermable layers of rock and clay. A bibliography on spontaneous potential in boreholes has been compiled by the USGS with some papers dating back to the 1940's.

The real questions are how practical and economically viable this approach will be for medium to large-scale power generation. For natural sites (e.g. permeable rock layers), what type of electrodes can be used, how well will they resist corrosion, and how large must they be? The bottom line: how much will the power cost over the entire life cycle in terms of $ per KWH?

For manufactured microchannel membranes or devices, added questions are the cost of manufacture and the lifespan of the device. How easily will the pores become clogged, what steps must be taken to prevent this, how long will it take for the pores to erode over time, and what is the expected lifetime of the microchannel device?

One big difference between pure science and engineering is that engineers need to factor in economics.

If we take one liter (1 kg) of water at a pressure of 30 cm, then the energy contained is 2.94 J, of which 0.12 J will be available as electrical output. By comparison, a 1500 mAh NiMH battery can store 6500 J. The efficiency of the water battery can probably be improved, but let's face it, for small volumes and reasonable pressures, the stored energy density will never be very high.

If we take one liter (1 kg) of water at a pressure of 30 cm, then the energy contained is 2.94 J, of which 0.12 J will be available as electrical output. By comparison, a 1500 mAh NiMH battery can store 6500 J. The efficiency of the water battery can probably be improved, but let's face it, for small volumes and reasonable pressures, the stored energy density will never be very high.

I saw this on CNN and immediately read the actual article published in the Journal of Measurement Science Technology. (probably need an institutional subscription to access the article.) One of the co-authors works for Campden & Chorleywood Food Research Association, which is presumbly where the funding came from (the sample preparation section mentions that the cookies were baked there).

Obviously companies that are in the business of selling cookies will do research into problems associated with their product. Broken cookies are a big deal. I open my Chips Ahoy and find a bunch of them broken, I'm a bit annoyed. I might even switch to Keebler cookies if there's don't break as much.

Basic experimental method (at least from what I can gather looking at the article). Take cookie, put it in environment with a given humidity and allow to equilibrate. Then transfer to new chamber with different humidity and watch how the cookie swells over time with speckle interferometry measurements to measure displacement and strain (I don't really understand how that part works). From this, determine a hygroscopic expansion coefficient and publish your work in a random journal.

Unfortunately, they really didn't test a variety of cookies and really didn't go into much detail on the type of cookie they did test. Would have been interesting if they did comparitive work between chocolate chip vs. snickerdoodles...

I saw this on CNN and immediately read the actual article published in the Journal of Measurement Science Technology. (probably need an institutional subscription to access the article.) One of the co-authors works for Campden & Chorleywood Food Research Association, which is presumbly where the funding came from (the sample preparation section mentions that the cookies were baked there).

Obviously companies that are in the business of selling cookies will do research into problems associated with their product. Broken cookies are a big deal. I open my Chips Ahoy and find a bunch of them broken, I'm a bit annoyed. I might even switch to Keebler cookies if there's don't break as much.

Basic experimental method (at least from what I can gather looking at the article). Take cookie, put it in environment with a given humidity and allow to equilibrate. Then transfer to new chamber with different humidity and watch how the cookie swells over time with speckle interferometry measurements to measure displacement and strain (I don't really understand how that part works). From this, determine a hygroscopic expansion coefficient and publish your work in a random journal.

Unfortunately, they really didn't test a variety of cookies and really didn't go into much detail on the type of cookie they did test. Would have been interesting if they did comparitive work between chocolate chip vs. snickerdoodles...

Pretty cool.

I beg to differ. Silicon has been made to emit light in various ways for over a decade.

"Scientists at Surrey University, led by researcher Kevin Homewood, are showing off a prototype silicon-based light-emitting diode (LED) -- an invention that could be of significance to the whole electronics and communication industry.

"By enabling silicon to emit light, the scientists say they may have found a way to use light to efficiently transfer data around microchips. This could lead to smaller, more powerful computers and improve data communications significantly."

ZDNet UK: Light-emitting silicon boosts chip speeds: 8th March 2001

"The photoluminescence emanating from a regular array of 1.2 m sized dots composed of Si nanocrystals was studied with spatial, spectral and temporal resolution."

New Journal of Physics: Nanostructuration with visible-light-emitting silicon nanocrystals

"GENEVA, Switzerland -- STMicrolectronics claims to have achieved a breakthrough in the creation of light-emitting silicon and said it would have engineering samples of monolithic silicon devices based on the technology, combining electrical isolation and optical communication, before the end of 2002.

"The development allows silicon light emitters to match the efficiency of compound semiconductor materials such as gallium arsenide for the first time, the company said."

EE Times: STMicro claims light-emitting silicon breakthrough: October 28, 2002

"The discovery of visible luminescence from porous silicon [1] has stimulated a large interest in this material. Numerous studies have demonstrated that it is possible to achieve efficient visible luminescence from porous silicon layers [2]. This material system has significant economic potential as efficient visible emitters could be fabricated on silicon wafers and incorporated with current microelectronic devices using existing silicon processing technologies."

[1] L. T. Canham. "Silicon quantum wire array fabrication by electrochemical and chemical dissolution of wafers." Appl. Phys.Lett., 1990, 57 1046 - 1048.

[2] For a recent review of the work in porous silicon see : Thin Solid Films, 1995, 225 and "Porous Silicon", edited by Z. Chuan and R Tsu, World Scientific, Singapore, 1995.

A Visible Large Area Light Emitting Diode Fabricated From Porous Silicon Using A Conducting Polyaniline Contact

BTW, technically, photocells are optoelectronic devices, as are LEDs.

The actual papers are available online.
Part I
Part II

Mirrored:
Part I
Part II

The actual papers are available online.
Part I
Part II

Mirrored:
Part I
Part II

Future of user/subscriber go-everywhere & do-everything (GoDo for short) computing would include communications (GSM, WiFi 802.11x, Bluetooth, and IR/RF capabilities included). Still ... I would select Transmeta code-morphing processors as the technology edge for that future not Intel, Motorola, or TI ... though TI does now have a chip set that comes closer to the above stated goal for digital transmission systems. Transmeta code-morphing processors provide the ability to redefine operational spectrum requirements as you travel locally and globally with (I suspect, don't know?) less complex circuits/chip sets. The technology is known as Software Definable Radios (SDR). The future looks good to me ....

Related Links:

SDR.org - http://www.sdrforum.org/sdr_primer.html

TI DR Chip Set - http://www.eetimes.com/story/OEG20020109S0063

Transmeta - http://www.transmeta.com

Airship - http://wireless.iop.org/articles/feature/1/1/3/1

http://www.airship.com/prod/uses_telecoms_frames.h tm

OldHawk777

Reality is a self-induced hallucination.

Hall, J Storrs, Louis Steinberg and Brian D Davison (1998) "Combining agoric and genetic methods in stochastic design" Nanotechnology 9 No 3 (September 1998) 274-284

the paper can be found here

AFAIK 'Gravity Waves' are not bound by the speed of light, they are instantaneous.

Quote from this page: "Gravitational waves are a prediction of Einstein's general relativity theory which describes gravity as distortions, caused by mass, of the very fabric of the Universe - spacetime. They are ripples in the spacetime fabric that travel outwards at the speed of light."

However measurements are on the way to test this.

Personally I don't think the physics winner (Demonstration of the Exponential Decay Law Using Beer Froth) satisfies the awards criteria for achievements that "cannot or should not be reproduced." I know once I finish work to today I plan to try to reproduce it!

There's a PDF of the real journal article available from Nanotechnology's site.

In the article they say that their atomic memory has an energy density of 250 terabits per square inch (compared to 100 gigabits per square inch for a hard drive). A CD-ROM has 14 square inches of recordable area. If one were to use this technique on a surface the size of a CD-ROM, that would give:

(14 square inches) * (250 terabits/square inch) / (8 bits/byte) = 437.5 terabytes

Incredibly huge, but I'm sure there's a number of people who would still be able to fill it up.

It's was either Slashdot or The Register where I got this link from a few months ago. It's about the same subject, but goes as far to mention that this technology can be used to guide individual atoms through the fiber tubes. The article says that the research on this is just beginning, and will be used to measuring gravitational fields and the like... I'm not too up on my physics, but does anyone see this akin to teleportation? It's only one atom at a time, and it's not a "wireless" solution, but you are moving actuall matter over high speed communications lines. Any physics people have an opinion? (as if I had to ask)