March 07, 2007
Media equivalence
I want to create a new term, media equivalence, for debates about the problems of civilization, technology and society. We currently have the term moral equivalence
From wikipedia, moral equivalence is a term used in political debate, usually to characterize in a negative way the claim that there can be no moral or ethical hierarchy decided between two sides in a conflict, nor in the actions or tactics of the two sides.
I propose that media equivalence be used when discussing the major problems of civilization, technology and society that it characterize in a negative way the claim that problems that are currently receiving airplay in the media are somehow equivalent to major problems (or are incorrectly linked as relevant to aspects of the debate because it is a top of the mind problem) of civilization, technology and society.
An example would be when one is talking about the sources of global electrical energy and the societal and global problem of air pollution which kills 3 million people per year (world health organization source). 85% of the global electrical power comes from fossil fuels. Someone could bring up a complaint against nuclear energy as a solution that they do not trust the Nuclear Regulatory Commission. The NRC will regulate and monitor the nuclear industry with the same assiduous attention to detail as the Army used at Walter Reed.
Note: the actual referenced discussion is paraphrased.
The Walter Reed incident being a current media scandal in 2007. However, this incident of some hospital rooms being in bad repair and having some cleanliness issues is nowhere near the same scale of the societal problem being discussed. No proven linkages to actual deaths caused.
The entire Iraq War is actually a much smaller problem than societal energy choices as well by many measures.
1. Iraq War is in many ways a by-product of historical energy choices.
2. Far fewer deaths per year than air pollution.
3. Likely fewer long term effects.
4. No potential for global climate change.
Walter Reed is a very small incident related to a smaller problem.
From wikipedia, moral equivalence is a term used in political debate, usually to characterize in a negative way the claim that there can be no moral or ethical hierarchy decided between two sides in a conflict, nor in the actions or tactics of the two sides.
I propose that media equivalence be used when discussing the major problems of civilization, technology and society that it characterize in a negative way the claim that problems that are currently receiving airplay in the media are somehow equivalent to major problems (or are incorrectly linked as relevant to aspects of the debate because it is a top of the mind problem) of civilization, technology and society.
An example would be when one is talking about the sources of global electrical energy and the societal and global problem of air pollution which kills 3 million people per year (world health organization source). 85% of the global electrical power comes from fossil fuels. Someone could bring up a complaint against nuclear energy as a solution that they do not trust the Nuclear Regulatory Commission. The NRC will regulate and monitor the nuclear industry with the same assiduous attention to detail as the Army used at Walter Reed.
Note: the actual referenced discussion is paraphrased.
The Walter Reed incident being a current media scandal in 2007. However, this incident of some hospital rooms being in bad repair and having some cleanliness issues is nowhere near the same scale of the societal problem being discussed. No proven linkages to actual deaths caused.
The entire Iraq War is actually a much smaller problem than societal energy choices as well by many measures.
1. Iraq War is in many ways a by-product of historical energy choices.
2. Far fewer deaths per year than air pollution.
3. Likely fewer long term effects.
4. No potential for global climate change.
Walter Reed is a very small incident related to a smaller problem.
Evidence for New particle physics model
Evidence for particles beyond the standard model of physics The Next-to-minimal supersymmetric standard model seems to fit the data that has been found. We will not know for sure until about 2009 when enough data has been gathered by the new Large Hadron Collider (LHC) that start this year.
Although He and colleagues showed in an earlier paper that the HyperCP result may be explained by the SM if there is no new particle, the implications of a new particle are considerable. If scientists find that particle X is indeed a new particle belonging to a different model, the breakdown of the SM would open up new doors for future investigations in many areas, and possibly answer many questions unanswered by the SM.
”The presence of the superpartners results in the cancellation of the large quantum corrections, leading to a Higgs mass at the desired level,” he said. “The minimal version of such models is called the Minimal Supersymmetric Standard Model (MSSM). The MSSM is a very attractive model in many ways, but it does not address the question of why the electroweak scale is much smaller than the Planck scale to begin with—this is the so-called mu problem.
“Interestingly, the Next-to-Minimal Supersymmetric Standard Model (NMSSM) solves this problem by adding a set of two particles to the MSSM in such a way that the electroweak scale can be naturally small. The NMSSM has been extensively studied in the literature and has many other interesting features. It is therefore a well-motivated model.”
Although physicists need to be careful before discarding an old model and confirming a new model. I do not have that restriction. I am willing to start favoring the NMSSM model now and if the evidence starts looking could for confirmation was still looking good in 2008 would be willing to bet that is way it will break.
Although He and colleagues showed in an earlier paper that the HyperCP result may be explained by the SM if there is no new particle, the implications of a new particle are considerable. If scientists find that particle X is indeed a new particle belonging to a different model, the breakdown of the SM would open up new doors for future investigations in many areas, and possibly answer many questions unanswered by the SM.
”The presence of the superpartners results in the cancellation of the large quantum corrections, leading to a Higgs mass at the desired level,” he said. “The minimal version of such models is called the Minimal Supersymmetric Standard Model (MSSM). The MSSM is a very attractive model in many ways, but it does not address the question of why the electroweak scale is much smaller than the Planck scale to begin with—this is the so-called mu problem.
“Interestingly, the Next-to-Minimal Supersymmetric Standard Model (NMSSM) solves this problem by adding a set of two particles to the MSSM in such a way that the electroweak scale can be naturally small. The NMSSM has been extensively studied in the literature and has many other interesting features. It is therefore a well-motivated model.”
Although physicists need to be careful before discarding an old model and confirming a new model. I do not have that restriction. I am willing to start favoring the NMSSM model now and if the evidence starts looking could for confirmation was still looking good in 2008 would be willing to bet that is way it will break.
March 05, 2007
Solar sail progress is difficult to assess
Different materials for solar sails with wide variation in capability are all in development. The lighter the sail then the faster it will accelerate.
This link has a table which shows the different speeds possible with different accelerations.
The carbon nanotube sail has the highest potential. 1 square kilometer 30 kg or 0.03 grams per square meter
Other work is for rudimentary metal sail with low size (70 square meter sail) and high weight (thus low performance with 20 g per square meter.)
Size and weight make a huge difference in performance.
From 2000 there was what seemed like a promising and simple approach.
Thicker carbon but still 5 grams per square meter
The New Energy systems material is now 3 grams per square meter. The New Energy system material has the advantage of being stiffer and able to support itself and hold a shape.
If you have a nanofactory or anything close that means the top end of the carbon nanotube solar sail performance should fall out as a precursor capabilitity.
This link has a table which shows the different speeds possible with different accelerations.
The carbon nanotube sail has the highest potential. 1 square kilometer 30 kg or 0.03 grams per square meter
Other work is for rudimentary metal sail with low size (70 square meter sail) and high weight (thus low performance with 20 g per square meter.)
Size and weight make a huge difference in performance.
From 2000 there was what seemed like a promising and simple approach.
Thicker carbon but still 5 grams per square meter
The New Energy systems material is now 3 grams per square meter. The New Energy system material has the advantage of being stiffer and able to support itself and hold a shape.
If you have a nanofactory or anything close that means the top end of the carbon nanotube solar sail performance should fall out as a precursor capabilitity.
March 02, 2007
Stanford technology predictions partial review
Reviewing the Delta scan predictions of the Stanford humanities lab.
I had already reviewed one of the predictions
Here are several of the computer related predicions
They predict Working prototypes of quantum computers may be demonstrated by 2040
The working prototype demo was Feb 13 of this year By next year quantums will be well scaled up and commercial.
Nanoscale physical materials that can be automatically assembled into useful configurations by computer instructions could usher in a new era in manufacturing. 11-20 years It is inprecise because certain DNA nanotechnology already qualifies as assembled via computer instructions. If they are talking about diamondoid molecular manufacturing then the timeframe is not unreasonable.
I had already reviewed one of the predictions
Here are several of the computer related predicions
They predict Working prototypes of quantum computers may be demonstrated by 2040
The working prototype demo was Feb 13 of this year By next year quantums will be well scaled up and commercial.
Nanoscale physical materials that can be automatically assembled into useful configurations by computer instructions could usher in a new era in manufacturing. 11-20 years It is inprecise because certain DNA nanotechnology already qualifies as assembled via computer instructions. If they are talking about diamondoid molecular manufacturing then the timeframe is not unreasonable.
Bigelow aerospace plans L1 and lunar facilities
Bigelow Aerospace is gearing up to launchits second prototype space station into orbit. The company has set its sights on something much, much bigger: a project to assemble full-blown space villages at L1 orbit and then drop them to the lunar surface, ready for immediate move-in.
The next test module, Genesis 2, is due for launch in April – with a larger prototype, known as Galaxy, tentatively scheduled for liftoff next year. Bigelow's plan calls for launching the company's first space "hotel" capable of accommodating guests (or researchers, for that matter) in 2010.
Getting all that right is "Job One," Bigelow told me. But by 2012, the focus could start shifting from low Earth orbit, or LEO, farther out into space. One of the key places in Bigelow's plan is a point about 200,000 miles (323,000 kilometers) out from Earth in the moon's direction, where the pulls of terrestrial and lunar gravity balance each other.
Bigelow would turn that region of space, called L1, into a construction zone. Inflatable modules would be linked up with propulsion/power systems and support structures, and then the completed base would be lowered down to the moon's surface, all in one piece.
Once the moon base has been set down, dirt would be piled on top, using a technique that Bigelow plans to start testing later this year at his Las Vegas headquarters. The moon dirt, more technically known as regolith, would serve to shield the base's occupants from the harsh radiation hitting the lunar surface.
The next test module, Genesis 2, is due for launch in April – with a larger prototype, known as Galaxy, tentatively scheduled for liftoff next year. Bigelow's plan calls for launching the company's first space "hotel" capable of accommodating guests (or researchers, for that matter) in 2010.
Getting all that right is "Job One," Bigelow told me. But by 2012, the focus could start shifting from low Earth orbit, or LEO, farther out into space. One of the key places in Bigelow's plan is a point about 200,000 miles (323,000 kilometers) out from Earth in the moon's direction, where the pulls of terrestrial and lunar gravity balance each other.
Bigelow would turn that region of space, called L1, into a construction zone. Inflatable modules would be linked up with propulsion/power systems and support structures, and then the completed base would be lowered down to the moon's surface, all in one piece.
Once the moon base has been set down, dirt would be piled on top, using a technique that Bigelow plans to start testing later this year at his Las Vegas headquarters. The moon dirt, more technically known as regolith, would serve to shield the base's occupants from the harsh radiation hitting the lunar surface.
How Numenta will work
Wired has an interview with Jeff Hawkins about how his Numenta Artificial Intelligence system will work
Scan and match
1) The system is shown a poor-quality image of a helicopter moving across a screen. It’s read by low-level nodes that each see a 4 x 4-pixel section of the image.
2) The low-level nodes pass the pattern they see up to the next level.
3) Intermediate nodes aggregate input from the low-level nodes to form shapes.
4) The top-level node compares the shapes against a library of objects and selects the best match.
Predict and refine
5) That info is passed back down to the intermediate - level nodes so they can better predict what shape they’ll see next.
6) Data from higher-up nodes allows the bottom nodes to clean up the image by ignoring pixels that don’t match the expected pattern (indicated above by an X). This entire process repeats until the image is crisp.
Dileep George built an original demonstration program, a basic representation of the process used in the human visual cortex. Most modeling programs are linear; they process data and make calculations in one direction. But George designed multiple, parallel layers of nodes — each representing thousands of neurons in cortical columns and each a small program with its own ability to process information, remember patterns, and make predictions.
George and Hawkins called the new technology hierarchical temporal memory, or HTM. An HTM consists of a pyramid of nodes, each encoded with a set of statistical formulas. The whole HTM is pointed at a data set, and the nodes create representations of the world the data describes — whether a series of pictures or the temperature fluctuations of a river. The temporal label reflects the fact that in order to learn, an HTM has to be fed information with a time component — say, pictures moving across a screen or temperatures rising and falling over a week. Just as with the brain, the easiest way for an HTM to learn to identify an object is by recognizing that its elements — the four legs of a dog, the lines of a letter in the alphabet — are consistently found in similar arrangements. Other than that, an HTM is agnostic; it can form a model of just about any set of data it’s exposed to. And, just as your cortex can combine sound with vision to confirm that you are seeing a dog instead of a fox, HTMs can also be hooked together. Most important, Hawkins says, an HTM can do what humans start doing from birth but that computers never have: not just learn, but generalize.
An HTM trained to identify helicopters from picture can be fed images it has never seen before, images of highly distorted helicopters oriented in various directions. To human eyes, each was still easily recognizable. Computers, however, haven’t traditionally been able to handle such deviations from what they’ve been programmed to detect, which is why spambots are foiled by strings of fuzzy letters that humans easily type in. George clicked on a picture, and after a few seconds the program spit out the correct identification: helicopter. It also cleaned up the image, just as our visual cortex does when it turns the messy data arriving from our retinas into clear images in our mind. The HTM even seems to handle optical illusions much like the human cortex. When George showed his HTM a capital A without its central horizontal line, the software filled in the missing information, just as our brains would.
Numenta is being applied to help monitor the sensors for air traffic control and il platforms. There are seeing good results with speed improvements over traditional approaches and correct identification of high risk situations. There is no degradation with more information as is the case with some AI systems.
Comparing modern skeptism about molecular nanotechnology with FPGA in 1957
Chris Pheonix has a though experiment of taking an FPGA chip back in time to 1957. He indicates the problems that would encountered trying to get the engineers of the day to accept that the FPGA could work and to believe in it enough to invest the time, money and effort into making the connections and supporting systems to program the FPGA and make it function.
The opinions of skeptics are important in determining the schedule by which new ideas are incorporated into the grand system of technology. It may be the case that molecular manufacturing proposals in the mid-1980's simply could not have hoped to attract serious investment, regardless of how carefully the technical case was presented. An extension of this argument would suggest that molecular manufacturing will only be developed once it is no longer revolutionary. But even if that is the case, technologies that are evolutionary within their field can have revolutionary impacts in other areas.
The IBM PC was only an evolutionary step forward from earlier hobby computers, but it revolutionized the relationship between office workers and computers. Without a forward-looking development program, molecular manufacturing may not be developed until other nanotechnologies are capable of building engineered molecular machines --say, around 2020 or perhaps even 2025. But even at that late date, the simplicity, flexibility, and affordability of molecular manufacturing could be expected to open up revolutionary opportunities in fields from medicine to aerospace. And we expect that, as the possibilities inherent in molecular manufacturing become widely accepted, a targeted development program probably will be started within the next few years, leading to development of basic (but revolutionary) molecular manufacturing not long after.
Photolithography was applied to making the first circuits in 1957
October 1957, staff at DOFL used photoengraving and photomechanical techniques to construct the first electronic circuit that incorporated nonprepackaged transistors and diodes as integral parts. The integrated circuit was patented in 1959.
Vacuum tube computers were still the most powerful machines up to 1958
The first integrated circuits contained only a few transistors. Called "Small-Scale Integration" (SSI), they used circuits containing transistors numbering in the tens.
SSI circuits were crucial to early aerospace projects, and vice-versa. Both the Minuteman missile and Apollo program needed lightweight digital computers for their inertially-guided flight computers; the Apollo guidance computer led and motivated the integrated-circuit technology, while the Minuteman missile forced it into mass-production.
These programs purchased almost all of the available integrated circuits from 1960 through 1963, and almost alone provided the demand that funded the production improvements to get the production costs from $1000/circuit (in 1960 dollars) to merely $25/circuit (in 1963 dollars). They began to appear in consumer products at the turn of the decade, a typical application being FM inter-carrier sound processing in television receivers.
The next step in the development of integrated circuits, taken in the late 1960s, introduced devices which contained hundreds of transistors on each chip, called "Medium-Scale Integration" (MSI).
They were attractive economically because while they cost little more to produce than SSI devices, they allowed more complex systems to be produced using smaller circuit boards, less assembly work (because of fewer separate components), and a number of other advantages.
Further development, driven by the same economic factors, led to "Large-Scale Integration" (LSI) in the mid 1970s, with tens of thousands of transistors per chip.
As I track the progress of technology on this site, the size of the leap to molecular manufacturing is rapidly becoming a smaller one. The expanding space of DNA nanotechnology, directed self assembly, synthetic biology, advanced lithography/nanoimprinting and other techniques for fine control at the 10 nanometer level are setting the stage for a fully enable molecular nanotechnology capability. These are early capabilities in molecular control. I think they are somewhat akin to transistors in the development of computers. They are useful and have some advantages over traditional approaches but they do not scale up as well as the IC systems. They are part of the basis for what will become ICs. Molecular systems will reach there promise when we have a few more key processes and methods to enable super high volume scaling.
Early molecular nanotechnology will have labs on a chip, microbubble circuitry, graphene membranes, other nanoscale membranes for supporting system components.
Also, there will be system architectures and societal experience with precursor systems like from advanced fabber and prototyping systems and modular macroscale robots. Nanoparticles and nanomaterials are already being widely adopted. Carbon nanotubes have already made impressive gains and will be moving from niche applications and research into the mainstream over this year and the next three years.
The opinions of skeptics are important in determining the schedule by which new ideas are incorporated into the grand system of technology. It may be the case that molecular manufacturing proposals in the mid-1980's simply could not have hoped to attract serious investment, regardless of how carefully the technical case was presented. An extension of this argument would suggest that molecular manufacturing will only be developed once it is no longer revolutionary. But even if that is the case, technologies that are evolutionary within their field can have revolutionary impacts in other areas.
The IBM PC was only an evolutionary step forward from earlier hobby computers, but it revolutionized the relationship between office workers and computers. Without a forward-looking development program, molecular manufacturing may not be developed until other nanotechnologies are capable of building engineered molecular machines --say, around 2020 or perhaps even 2025. But even at that late date, the simplicity, flexibility, and affordability of molecular manufacturing could be expected to open up revolutionary opportunities in fields from medicine to aerospace. And we expect that, as the possibilities inherent in molecular manufacturing become widely accepted, a targeted development program probably will be started within the next few years, leading to development of basic (but revolutionary) molecular manufacturing not long after.
Photolithography was applied to making the first circuits in 1957
October 1957, staff at DOFL used photoengraving and photomechanical techniques to construct the first electronic circuit that incorporated nonprepackaged transistors and diodes as integral parts. The integrated circuit was patented in 1959.
Vacuum tube computers were still the most powerful machines up to 1958
The first integrated circuits contained only a few transistors. Called "Small-Scale Integration" (SSI), they used circuits containing transistors numbering in the tens.
SSI circuits were crucial to early aerospace projects, and vice-versa. Both the Minuteman missile and Apollo program needed lightweight digital computers for their inertially-guided flight computers; the Apollo guidance computer led and motivated the integrated-circuit technology, while the Minuteman missile forced it into mass-production.
These programs purchased almost all of the available integrated circuits from 1960 through 1963, and almost alone provided the demand that funded the production improvements to get the production costs from $1000/circuit (in 1960 dollars) to merely $25/circuit (in 1963 dollars). They began to appear in consumer products at the turn of the decade, a typical application being FM inter-carrier sound processing in television receivers.
The next step in the development of integrated circuits, taken in the late 1960s, introduced devices which contained hundreds of transistors on each chip, called "Medium-Scale Integration" (MSI).
They were attractive economically because while they cost little more to produce than SSI devices, they allowed more complex systems to be produced using smaller circuit boards, less assembly work (because of fewer separate components), and a number of other advantages.
Further development, driven by the same economic factors, led to "Large-Scale Integration" (LSI) in the mid 1970s, with tens of thousands of transistors per chip.
As I track the progress of technology on this site, the size of the leap to molecular manufacturing is rapidly becoming a smaller one. The expanding space of DNA nanotechnology, directed self assembly, synthetic biology, advanced lithography/nanoimprinting and other techniques for fine control at the 10 nanometer level are setting the stage for a fully enable molecular nanotechnology capability. These are early capabilities in molecular control. I think they are somewhat akin to transistors in the development of computers. They are useful and have some advantages over traditional approaches but they do not scale up as well as the IC systems. They are part of the basis for what will become ICs. Molecular systems will reach there promise when we have a few more key processes and methods to enable super high volume scaling.
Early molecular nanotechnology will have labs on a chip, microbubble circuitry, graphene membranes, other nanoscale membranes for supporting system components.
Also, there will be system architectures and societal experience with precursor systems like from advanced fabber and prototyping systems and modular macroscale robots. Nanoparticles and nanomaterials are already being widely adopted. Carbon nanotubes have already made impressive gains and will be moving from niche applications and research into the mainstream over this year and the next three years.
New methods for DNA nanotechnology structures
I think the main benefit for these new methods is to extend the capabilities of these DNA nanotechnology systems along with DNA origami, Ned Seemans DNA systems, rotaxane molecular chemistry, other molecular chemistry, laser/electric manipulation, synthetic biology and advanced self assembly. More tools and methods in our rapidly growing molecular manipulation toolbox.
Scientists from Duke University have recently demonstrated a new method for assembling large, low-cost DNA nanostructures, in part by reusing the “sticky-ends,” the broken DNA strands used to connect the nanostructures. In their hierarchical self-assembly method, the scientists have demonstrated one of the largest programmable synthetic nanostructures ever synthesized.
The hierarchical approach to building nanostructures from DNA, beginning with nine oligonucleotides and resulting in an 8 x 8 grid. Credit: Constantin Pistol, et al.
At a molecular weight of 8960 kD, the 64-motif structure is one of the largest programmable synthetic nanostructures ever synthesized. The scientists also predict that this method can be scaled even further before reaching a limit imposed when the generic interactions begin to dominate the process. However, studies in periodic DNA crystal formation suggest that the scale limit is nearly macroscopic.
The first type, the “generic” sticky-end, binds with only one helix instead of the normal two. This binding provides a relatively unstable interaction, which makes it easier to individually program two adjacent grids later on. The second type, the “specific” sticky-end, provides a stronger interaction and can control the weak interactions between the generic sticky-ends.
In one fabrication method, the scientists bound together two 4 x 4 grids, using two generic sticky-ends and one specific sticky-end (the fourth grid arm was left open for identification purposes). The scientists found that the single specific sticky-end could dominate the entire connection, providing a scalable assembly method.
In the second method, Pistol and Dwyer used all specific sticky-ends to connect two 4 x 4 grids. They found that, after the grids were connected, the sticky-ends could be reused in other connections. In this method, the scientists assembled four 4 x 4 grids to produce a 64-motif structure.
In analyzing their structures for defects, Pistol and Dwyer found that missing motifs were common, requiring defect-tolerant designs in future large-scale assemblies. “One of the benefits of DNA nanostructures for computers is device density,” Dwyer said. “The grid has a pitch of 20nm, and this is about half of the smallest device feature in Intel's latest lithography process. The other benefit is manufacturing scale. Each experiment created a vast number of structures (~1012 or more) and this holds the promise of more complex and higher performance computers in the future.”
Scientists from Duke University have recently demonstrated a new method for assembling large, low-cost DNA nanostructures, in part by reusing the “sticky-ends,” the broken DNA strands used to connect the nanostructures. In their hierarchical self-assembly method, the scientists have demonstrated one of the largest programmable synthetic nanostructures ever synthesized.
The hierarchical approach to building nanostructures from DNA, beginning with nine oligonucleotides and resulting in an 8 x 8 grid. Credit: Constantin Pistol, et al.
At a molecular weight of 8960 kD, the 64-motif structure is one of the largest programmable synthetic nanostructures ever synthesized. The scientists also predict that this method can be scaled even further before reaching a limit imposed when the generic interactions begin to dominate the process. However, studies in periodic DNA crystal formation suggest that the scale limit is nearly macroscopic.
The first type, the “generic” sticky-end, binds with only one helix instead of the normal two. This binding provides a relatively unstable interaction, which makes it easier to individually program two adjacent grids later on. The second type, the “specific” sticky-end, provides a stronger interaction and can control the weak interactions between the generic sticky-ends.
In one fabrication method, the scientists bound together two 4 x 4 grids, using two generic sticky-ends and one specific sticky-end (the fourth grid arm was left open for identification purposes). The scientists found that the single specific sticky-end could dominate the entire connection, providing a scalable assembly method.
In the second method, Pistol and Dwyer used all specific sticky-ends to connect two 4 x 4 grids. They found that, after the grids were connected, the sticky-ends could be reused in other connections. In this method, the scientists assembled four 4 x 4 grids to produce a 64-motif structure.
In analyzing their structures for defects, Pistol and Dwyer found that missing motifs were common, requiring defect-tolerant designs in future large-scale assemblies. “One of the benefits of DNA nanostructures for computers is device density,” Dwyer said. “The grid has a pitch of 20nm, and this is about half of the smallest device feature in Intel's latest lithography process. The other benefit is manufacturing scale. Each experiment created a vast number of structures (~1012 or more) and this holds the promise of more complex and higher performance computers in the future.”
March 01, 2007
Foolproof Quantum Cryptography
Adding decoy photons to quantum-cryptographic signals should finally make them "unconditionally secure."
Researchers at Toshiba, in Cambridge, U.K., have found a way to plug a security hole that currently limits how far and how fast encryption keys can be distributed using existing quantum-cryptographic systems. The developments could broaden the commercial appeal of "unconditionally secure" quantum key distribution, says Andrew Shields, head of Quantum Information Group at Toshiba Research Europe, who led the research.
Quantum cryptography is currently only used for sending encryption keys between buildings by some banks and government departments. But systems can only guarantee security over relatively short distances. The challenge is to extend the range and increase the speed at which the keys can be sent so that they can be used more widely, says Shields.
Making quantum encryption totally secure will require the use of single-photon pulses. Pictured is a new light-emitting diode capable of generating such pulses.
Credit: Toshiba Research Europe Ltd.
In practice, however, this sort of unconditional security can only really be guaranteed if one's light source emits nothing but single photons. Since this is not the case in current quantum encryption, eavesdropping attacks are possible. In one strategy, an eavesdropper siphons off individual photons; this attack relies on the fact that some pulses will consist of more than one photon, meaning they won't be missed.
To get around this, existing commercial quantum-encryption systems use tricks to reduce the probability that pulses will contain multiple photons. For example, the systems might limit the intensity of each pulse and reduce the bit rate at which they are sent. However, the trade-off is that the weaker a pulse is, the less distance it can travel, while a slower bit rate will limit the speed at which keys can be distributed, says Shields.
Toshiba's solution is to include within the signal what Shields calls "decoy pulses." These pulses are randomly interspersed within the signal and are weaker than the rest of the signal. This means they rarely consist of more than one photon. If an eavesdropper tries blocking single photons while siphoning off multiple photons from the rest of the pulses, more of these decoy pulses will be blocked on average than will the rest of the signal. So by monitoring the proportion of signals to decoy pulses that make it through, it is possible to detect an attack.
Researchers at Toshiba, in Cambridge, U.K., have found a way to plug a security hole that currently limits how far and how fast encryption keys can be distributed using existing quantum-cryptographic systems. The developments could broaden the commercial appeal of "unconditionally secure" quantum key distribution, says Andrew Shields, head of Quantum Information Group at Toshiba Research Europe, who led the research.
Quantum cryptography is currently only used for sending encryption keys between buildings by some banks and government departments. But systems can only guarantee security over relatively short distances. The challenge is to extend the range and increase the speed at which the keys can be sent so that they can be used more widely, says Shields.
Making quantum encryption totally secure will require the use of single-photon pulses. Pictured is a new light-emitting diode capable of generating such pulses.
Credit: Toshiba Research Europe Ltd.
In practice, however, this sort of unconditional security can only really be guaranteed if one's light source emits nothing but single photons. Since this is not the case in current quantum encryption, eavesdropping attacks are possible. In one strategy, an eavesdropper siphons off individual photons; this attack relies on the fact that some pulses will consist of more than one photon, meaning they won't be missed.
To get around this, existing commercial quantum-encryption systems use tricks to reduce the probability that pulses will contain multiple photons. For example, the systems might limit the intensity of each pulse and reduce the bit rate at which they are sent. However, the trade-off is that the weaker a pulse is, the less distance it can travel, while a slower bit rate will limit the speed at which keys can be distributed, says Shields.
Toshiba's solution is to include within the signal what Shields calls "decoy pulses." These pulses are randomly interspersed within the signal and are weaker than the rest of the signal. This means they rarely consist of more than one photon. If an eavesdropper tries blocking single photons while siphoning off multiple photons from the rest of the pulses, more of these decoy pulses will be blocked on average than will the rest of the signal. So by monitoring the proportion of signals to decoy pulses that make it through, it is possible to detect an attack.
New Nanocoating breakthrough in non-Reflective material
A team of researchers from Rensselaer Polytechnic Institute has created the world’s first material that reflects virtually no light. Reporting in the March issue of Nature Photonics, they describe an optical coating made from the material that enables vastly improved control over the basic properties of light. The research could open the door to much brighter LEDs, more efficient solar cells, and a new class of "smart" light sources that adjust to specific environments, among many other potential applications
To achieve a very low refractive index, silica nanorods are deposited at an angle of precisely 45 degrees on top of a thin film of aluminum nitride. Credit: Rensselaer/Fred Schubert
Schubert and his coworkers have created a material with a refractive index of 1.05, which is extremely close to the refractive index of air and the lowest ever reported. Window glass, for comparison, has a refractive index of about 1.45.
he new optical coating could find use in just about any application where light travels into or out of a material, such as:
-- More efficient solar cells. The new coating could increase the amount of light reaching the active region of a solar cell by several percent, which could have a major impact on its performance. "Conventional coatings are not appropriate for a broad spectral source like the sun," Schubert said. "The sun emits light in the ultraviolet, infrared, and visible spectral range. To use all the energy provided by the sun, we don’t want any energy reflected by the solar cell surface."
-- Brighter LEDs. LEDs are increasingly being used in traffic signals, automotive lighting, and exit signs, because they draw far less electricity and last much longer than conventional fluorescent and incandescent bulbs. But current LEDs are not yet bright enough to replace the standard light bulb. Eliminating reflection could improve the luminance of LEDs, which could accelerate the replacement of conventional light sources by solid-state sources.
-- "Smart" lighting. Not only could improved LEDs provide significant energy savings, they also offer the potential for totally new functionalities. Schubert’s new technique allows for vastly improved control of the basic properties of light, which could allow "smart" light sources to adjust to specific environments. Smart light sources offer the potential to alter human circadian rhythms to match changing work schedules, or to allow an automobile to imperceptibly communicate with the car behind it, according to Schubert.
- Optical interconnects. For many computing applications, it would be ideal to communicate using photons, as opposed to the electrons that are found in electrical circuits. This is the basis of the burgeoning field of photonics. The new materials could help achieve greater control over light, helping to sustain the burgeoning photonics revolution, Schubert said.
-- High-reflectance mirrors. The idea of anti-reflection coatings also could be turned on its head, according to Schubert. The ability to precisely control a material’s refractive index could be used to make extremely high-reflectance mirrors, which are used in many optical components including telescopes, optoelectronic devices, and sensors.
-- Black body radiation. The development could also advance fundamental science. A material that reflects no light is known as an ideal "black body." No such material has been available to scientists, until now. Researchers could use an ideal black body to shed light on quantum mechanics, the much-touted theory from physics that explains the inherent "weirdness" of the atomic realm.
To achieve a very low refractive index, silica nanorods are deposited at an angle of precisely 45 degrees on top of a thin film of aluminum nitride. Credit: Rensselaer/Fred Schubert
Schubert and his coworkers have created a material with a refractive index of 1.05, which is extremely close to the refractive index of air and the lowest ever reported. Window glass, for comparison, has a refractive index of about 1.45.
he new optical coating could find use in just about any application where light travels into or out of a material, such as:
-- More efficient solar cells. The new coating could increase the amount of light reaching the active region of a solar cell by several percent, which could have a major impact on its performance. "Conventional coatings are not appropriate for a broad spectral source like the sun," Schubert said. "The sun emits light in the ultraviolet, infrared, and visible spectral range. To use all the energy provided by the sun, we don’t want any energy reflected by the solar cell surface."
-- Brighter LEDs. LEDs are increasingly being used in traffic signals, automotive lighting, and exit signs, because they draw far less electricity and last much longer than conventional fluorescent and incandescent bulbs. But current LEDs are not yet bright enough to replace the standard light bulb. Eliminating reflection could improve the luminance of LEDs, which could accelerate the replacement of conventional light sources by solid-state sources.
-- "Smart" lighting. Not only could improved LEDs provide significant energy savings, they also offer the potential for totally new functionalities. Schubert’s new technique allows for vastly improved control of the basic properties of light, which could allow "smart" light sources to adjust to specific environments. Smart light sources offer the potential to alter human circadian rhythms to match changing work schedules, or to allow an automobile to imperceptibly communicate with the car behind it, according to Schubert.
- Optical interconnects. For many computing applications, it would be ideal to communicate using photons, as opposed to the electrons that are found in electrical circuits. This is the basis of the burgeoning field of photonics. The new materials could help achieve greater control over light, helping to sustain the burgeoning photonics revolution, Schubert said.
-- High-reflectance mirrors. The idea of anti-reflection coatings also could be turned on its head, according to Schubert. The ability to precisely control a material’s refractive index could be used to make extremely high-reflectance mirrors, which are used in many optical components including telescopes, optoelectronic devices, and sensors.
-- Black body radiation. The development could also advance fundamental science. A material that reflects no light is known as an ideal "black body." No such material has been available to scientists, until now. Researchers could use an ideal black body to shed light on quantum mechanics, the much-touted theory from physics that explains the inherent "weirdness" of the atomic realm.
More accurate breakdown of energy equivalents
This is a more accurate breakdown of what equals one cubic mile of oil. The IEEE Spectrum comparison compares oil's inputs to the other's outputs.
The world's annual consumption, one cubic mile of oil, can be replaced by [this includes converting all cars and trucks to electric or PHEV/biofuels a likely 30-40 year effort with massive global pushes]:
* 700 1.1 GW nuclear plants,
* 1,550 500MW coal plants,
* 720,000 3MW wind turbines,
* Maybe 2 billion 2.1KW solar panels
If we were going to supply a cubic-mile-of-oil equivalent of heat and work from nuclear plants at 33% thermal efficiency (3.3 GW thermal input, 2.2 GW thermal + 1.1 GW electric output) it would take a lot less. If you cranked them for 50 years, a mere 14 1.1 GW plants could supply 771 GW-years of electricity and another 1540 GW-years of low-grade heat, more than satisfying the requirement of 1370 GW-years of heat from oil. Coal would do about about the same, but it would take 31 500 MW plants to equal the 14 nukes. Wind has no waste heat stream and couldn't do as well (the energy would have to be all electric), but the possibilities for solar are amazing. Solar heat (for space heat) can be collected for very little, sometimes for free with careful design. Supplying 770 GW-years of electricity from solar PV at 25% capacity factor would require only about 40 million 2.1 kW installations; doing a year's worth per year would require about 2 billion 2.1 kW systems, or about 700 watts per capita.
700 watts is about 10 of today's PV panels. The industrial nations could almost afford to give 10 panels to every child at birth, and cost improvements in the pipeline could extend this to much of the world in the next decade or two.
Other analysis
The world's annual consumption, one cubic mile of oil, can be replaced by [this includes converting all cars and trucks to electric or PHEV/biofuels a likely 30-40 year effort with massive global pushes]:
* 700 1.1 GW nuclear plants,
* 1,550 500MW coal plants,
* 720,000 3MW wind turbines,
* Maybe 2 billion 2.1KW solar panels
If we were going to supply a cubic-mile-of-oil equivalent of heat and work from nuclear plants at 33% thermal efficiency (3.3 GW thermal input, 2.2 GW thermal + 1.1 GW electric output) it would take a lot less. If you cranked them for 50 years, a mere 14 1.1 GW plants could supply 771 GW-years of electricity and another 1540 GW-years of low-grade heat, more than satisfying the requirement of 1370 GW-years of heat from oil. Coal would do about about the same, but it would take 31 500 MW plants to equal the 14 nukes. Wind has no waste heat stream and couldn't do as well (the energy would have to be all electric), but the possibilities for solar are amazing. Solar heat (for space heat) can be collected for very little, sometimes for free with careful design. Supplying 770 GW-years of electricity from solar PV at 25% capacity factor would require only about 40 million 2.1 kW installations; doing a year's worth per year would require about 2 billion 2.1 kW systems, or about 700 watts per capita.
700 watts is about 10 of today's PV panels. The industrial nations could almost afford to give 10 panels to every child at birth, and cost improvements in the pipeline could extend this to much of the world in the next decade or two.
Other analysis
Putting the brakes on laser mirror systems
I have described a bouncing laser mirror system for accelerating space vehicles to very fast speed. How would braking work ?
The braking is done with a receiving laser bounce system at your destination (like Mars)
OR
you would need to carry a good superconducting magnetic sail to slow you down
OR
you have to bring along a drive system to slow you down (like an ion drive, Vasimr or Minimag orion where you start slowing down halfway)
OR
you do not go faster than you can brake (aerobraking and airbags, whatever drive you have for braking etc...)
I would say that you first send over the robotic parts and gear on slower trips. Bigger, slower payloads with aerobraking and whatever else you have for braking. Maybe an early package would be the nuclear gas reactors (still to be made but on the drawing board) and laser, mirror systems. Send those multi-ton packages over on 96 day or 6 month trips. Whatever speed that you can brake safely from. Then the receiving lasers have power. Then you can do a better job of slowing in bound shipments. Then you can start sending things over faster. Go twice as slow send 4 times as much stuff. Go ten times slower and send 100 times as much stuff. The laser/mirror system is still very efficient in terms of the cost of consumables (mainly just electricity).
Ultimately a network of laser systems for accelerating and slowing vehicles would be needed.
The braking is done with a receiving laser bounce system at your destination (like Mars)
OR
you would need to carry a good superconducting magnetic sail to slow you down
OR
you have to bring along a drive system to slow you down (like an ion drive, Vasimr or Minimag orion where you start slowing down halfway)
OR
you do not go faster than you can brake (aerobraking and airbags, whatever drive you have for braking etc...)
I would say that you first send over the robotic parts and gear on slower trips. Bigger, slower payloads with aerobraking and whatever else you have for braking. Maybe an early package would be the nuclear gas reactors (still to be made but on the drawing board) and laser, mirror systems. Send those multi-ton packages over on 96 day or 6 month trips. Whatever speed that you can brake safely from. Then the receiving lasers have power. Then you can do a better job of slowing in bound shipments. Then you can start sending things over faster. Go twice as slow send 4 times as much stuff. Go ten times slower and send 100 times as much stuff. The laser/mirror system is still very efficient in terms of the cost of consumables (mainly just electricity).
Ultimately a network of laser systems for accelerating and slowing vehicles would be needed.
Path to detailed wiring diagram of the brain
Researchers at the Salk Institute for Biological Studies have jumped what many believe to be a major hurdle to preparing a detailed wiring diagram of the brain: identifying all of the connections to a single neuron. The researchers describe how they modified the deadly rabies virus, turning it into a tool that can cross the synaptic space of a targeted nerve cell just once to identify all the neurons to which it is directly connected.
Viruses that naturally spread between neurons have previously been used to outline the flow of nerve cell communication, but they have two drawbacks. First, once inside the brain, they keep spreading from cell to cell without stopping. Second, they cross different synapses – the specialized junctions between nerve cells - at different rates, crossing bigger, stronger synapses faster than smaller, weaker ones. Together these attributes make these viruses unable to determine exactly which cells are connected to which. The team of Salk researchers sought to create a modified virus whose spread could be limited to a single synaptic connection.
“The core idea is to use a virus that is missing a gene required for spreading across synapses but to provide the missing gene by some other means within the initially infected cells,” says Ian Wickersham, Ph.D., postdoctoral researcher and lead author on the project.
With the critical gene deleted from its genome, the virus is marooned inside a cell, unable to spread beyond it. However, supplying the missing gene in that same cell allows the virus to spread to cells that are directly connected to it. Since these neighboring cells lack the gene supplied in the first cell, the virus is stuck. Only the cells connected directly to the original cell are labeled.
You need two genes expressed in the cell or cell type of interest: TVA, to get the rabies virus in, and the missing viral gene so the virus can spread to connected cells,” says Wickersham.
They experimented on a neonatal rat brain: The result was spectacular: as expected, these red cells were selectively infected by the virus, which spread to hundreds of surrounding cells, turning them brilliantly fluorescent green. Once scientists can identify a neural circuit, they can then deactivate it, and test for changes in brain function.
Viruses that naturally spread between neurons have previously been used to outline the flow of nerve cell communication, but they have two drawbacks. First, once inside the brain, they keep spreading from cell to cell without stopping. Second, they cross different synapses – the specialized junctions between nerve cells - at different rates, crossing bigger, stronger synapses faster than smaller, weaker ones. Together these attributes make these viruses unable to determine exactly which cells are connected to which. The team of Salk researchers sought to create a modified virus whose spread could be limited to a single synaptic connection.
“The core idea is to use a virus that is missing a gene required for spreading across synapses but to provide the missing gene by some other means within the initially infected cells,” says Ian Wickersham, Ph.D., postdoctoral researcher and lead author on the project.
With the critical gene deleted from its genome, the virus is marooned inside a cell, unable to spread beyond it. However, supplying the missing gene in that same cell allows the virus to spread to cells that are directly connected to it. Since these neighboring cells lack the gene supplied in the first cell, the virus is stuck. Only the cells connected directly to the original cell are labeled.
You need two genes expressed in the cell or cell type of interest: TVA, to get the rabies virus in, and the missing viral gene so the virus can spread to connected cells,” says Wickersham.
They experimented on a neonatal rat brain: The result was spectacular: as expected, these red cells were selectively infected by the virus, which spread to hundreds of surrounding cells, turning them brilliantly fluorescent green. Once scientists can identify a neural circuit, they can then deactivate it, and test for changes in brain function.
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