Teaching math isn't about teaching a specific skill that everyone will use, it's about teaching how to approach problems quantitatively. At least it should be. As someone pointed out in a post further down, a lot of us don't use literary analysis in day to day life either but the reason to learn it is that learning different topics that require critical and logical thinking will arm students with better methods to approach problems with.
A physicist may well benefit a great deal from from having gone to English class in high school. Sure they only use make use of the basics, like correct spelling and grammar, every day but the style of critical thinking that is exercised in literary analysis is additional tool that they have. Similarly, math teaches and practices a way of approaching problems that other subjects don't address.
Someone who has an education in only a range of topics that is limited to their interests will be a flat, bland and incapable person.
That's absolutely right, if the market determines the going rate for bandwidth. Bandwidth is, after all, a finite resource; however, there is no competition and hence there are no market forces at play in this situation. That's where this whole can of worms came from in the first place. The whole industry is regulated because of the excessively high barriers to entry for new competitors. It's not going to be an ideal situation but it would be less bad if it was regulated well instead of being regulated by the CRTC.
Depends on where you live. If you live in Toronto, then it affects all of Canada because as far as you're concerned, Toronto = Canada.
Joking aside, Bell dominates the market in most of Ontario and Quebec. Most of the other providers in Quebec and Ontario are reselling Bell's bandwidth which means that this impacts a large portion of the internet business in Canada. Moreover, I'm sure it sets a precedent that would be relevant to resellers of Shaw or Tellus bandwidth in the West.
Shaw tends to be quite good compared to Bell but that could change. They have absurdly low data caps but they never enforce them; unlike Bell, which demands a pound of flesh for every GB over your 60 GB limit.
Let me take a run at explaining quantum computing less awkwardly than the article.
A quantum bit (qbit) may be in a 0 state, a 1 state or any linear superposition (combination) of the two, eg. 0 + i1. When measured, the outcome of the measurement can only be 0 or 1 with the probabilities of each being governed by the ratio of contributions to the qbit from the 0 and 1 components.
One qbit can usefully encode one bit of classical information (this is the point that most articles on the subject muddle up). Entangled qbits, however, also encode information into the relationship between them. More accurately, the state of the two qbits combined cannot be described by the individual states of each qbit. The number of possible states that the combined system can occupy is greater than the number of states that two unentangled qbits (or classical bits) could occupy. In other words, N entangled qbits occupy a much larger state space than 2^N, which is the state space for N classical bits.
A quantum register containing N qbits can yield an answer with, at most, 2^N bits of classical information once measured; however, the computation itself can be performed in a state space that is much larger than 2^N, hence the dramatic increase in computational power for certain algorithms. It's difficult to come up with algorithms that exploit the large quantum state space but yield a deterministic (rather than probabilistic answer). In some cases, however, even probabilistic answers may be okay if the correctness of the solution can be verified quickly with a classical algorithm and the quantum computation re-run.
No, you really don't want to fuck with customs officers. Be civil and try to ignore violations of your rights because you will only make your situation worse.
If you want to dick around with customs officers make damn sure you have absolutely nothing that you can't import and have declared everything that you need to (did you declare the bag of peanuts you got on the plane and have in your bag?) and that you have nowhere to be for a day or so.
I'm surprised that the US doesn't already have data retention laws. It still doesn't change a lot. Phone companies and ISPs already keep logs and police routinely subpoena them. This proposal isn't as dire as the summary title makes it seem; logs of who you talk to (which IP you connect to) are already kept for a long time. A more useful law would be one that places a maximum time on the retention period, not a minimum.
It also doesn't look like he's talking about getting one useful prototype chip working in five years. He seems to mean one spin transistor five years from now. That probably puts it at decades from hitting market and only if it's a more suitable technology than all the other technologies that could, just maybe, replace the current basic transistor design.
I'd agree with that. You should make the recommendation based on which piece of software is better suited to the task. The consensus of other posters seems to be that that isn't Plone. More generally, given two identical feature sets from a commercial and an open-source application, the argument of which to use in a business setting still shouldn't fall to idealism. You'd have to look at support and frequency of updates. An open-source project with a large community may well be suitable but a smaller project might not be.
Thanks for the detailed reply! There must be a pile of unwanted non-linear effects when sending that much light through a fiber amplifier. Cross-phase modulation and four-wave-mixing must make an appearance when you're trying to keep two polarization encoded (and phase-encoded!) signals separate.
The article implies that it's easy to do, there was simply never a need before. I seriously doubt that it's a trivial thing to accomplish a four-fold increase in bandwidth on existing infrastructure.
Polarization has a habit of wandering around in fiber. Temperature and physical movement of the fiber will change how the polarization is altered as it passes through the fiber. In a trans-oceanic fiber the effect could be dramatic; the polarization would likely wander around with quite a high frequency. This would need to be corrected for by periodically sending reference pulses though the fiber so that the receivers could be re-calibrated. Not too difficult, but any inaccessible repeaters would still need to be retrofitted. I also don't know if in-fiber amplifiers are polarization maintaining. They rely on a scattering process that might not be.
Phase-encoding has similar problems. Dispersion, the fact that different frequencies travel at different velocities (this leads to prisms separating white light into rainbows), will distort the pulse shape and shift the modulation envelope with respect to the phase. You either need very low dispersion fibers, and they already need to use the best available, or have some fancy processing at a receiver or repeater. Adding extra phase encoding simply implies that the current encoding method (probably straight-up, on-off encoding) is inefficient. That's not necessarily lack of foresight, that's because dense encoding is probably really hard to do in a dispersive medium like fiber. Again, it's not a trivial drop-in replacement.
The article downplays how hard these problems are. It implies that the engineers simply didn't think it through the first time around, but that's far from the case. A huge amount of money and effort goes into more efficiently encoding information in fiber. There probably is no drop in solution, but very clever design in new repeaters and amplifiers might squeeze some bonus bandwidth into existing cable.
It's probably two of them. Two degrees of freedom from polarization, two from phase.
If your information is carried on an amplitude modulated sine wave, you recover it by demodulating with another sine wave. Demodulating with an orthogonal function, cosine, yields nothing. So you can pack a second carrier with a cosine phase in there and then demodulate each with the correct phase to extract the modulation signal. I don't know much about how much cross-talk there would be but probably, in theory, as long as the modulation frequency (on the order of GHz) is slow compared to the carrier frequency (hundreds of THz), it's not too bad.
The Laws of Physics don't form a complete, formal logical system nor do they attempt to. The set of mathematical axioms used to describe the physical world doesn't need to be complete in order to be logically coherent; it can be proven using axioms that lie outside the set and still be useful and coherent.
There is a temptation to apply elegant theorems like Godel's to situations that they do not apply to and this is one of those cases. The Laws of Physics do not, in the sense of a formal system, attempt to prove themselves and hence Godel's theorem does not apply.
The work is related to trapping single, neutral atoms efficiently. Trapping techniques for bulk quantities of charged particles tend to be simpler. Slowing down energetic particles is probably tough, but doesn't relate to this research.
Photographs of trapped single atoms abound; they're just not that interesting. The atom will scatter light from the trapping beams and the scattered light can be easily imaged onto a camera. In fact, imaging is often used to characterize the trap. The atom just shows up as a blurry dot with the size of the blur being determined by the diffraction limit of the light or perhaps the tightness of the confinement. There's certainly no internal structure that would be resolvable.
I would imagine that it would be similar legally to applying mods or cracks to game consoles or iPhones. Breaking a digital lock is, in itself, illegal in some countries and that would certainly qualify. Beyond that, I've never really understood the argument that you can't do what you want with your phone/console/chip.
My question is how is the patch applied? Is it a firmware update on the processor itself? (Do processors have firmware to update?) Bios update? If it's in the operating system, what does the processor look like to a Linux kernel and how would one unlock it in that case? No doubt someone here has a better idea of how it will work than I do.
Let me provide some context. This research group specializes in manufacturing arbitrary waveguide structures on chips, then coupling particular quantum states of light into them. The idea is to turn a large optical table worth of mirrors into a tiny chip. What they have done here, is allowed a two photon input state to interfere with itself in the waveguide structure.
While interesting technically, it isn't exactly a huge leap forward because the interaction is linear. What's needed for deterministic quantum computation with light is a very non-linear process. The waveguide structure can replace a large number of mirrors and compact the optics into a tiny space but, at the end of the day, mirrors aren't all that interesting for quantum computation. It is, however, worthwhile because of the impressive miniaturization and the technical challenge of working with quantum light in such tiny structures. A strong non-linear component will be needed for true optical quantum computation, but chips like these show a lot of promise for handling a lot of state preparation and measurement.
It's a pretty damn big loophole. They used a 1 mW beam which is about as powerful as a laser pointer. That's many orders of magnitude larger than a single-photon level signal and should be very easy to detect. Not noticing a milliwatt of light hitting the detector in a quantum scheme is something like leaving a key written in plain text on a sticky note on your monitor and being shocked when your key is "hacked."
I'm sure there aren't many companies that would put up with that at all. That's why it would be so effective; not many ISPs would remain in business if they failed to protect their customers from such shut-offs.
Exactly. It's altogether too easy for professors to use PowerPoint slides as a crutch. There's no substitute for making a derivation in class with the students following along in their notebooks. "Here's a derivation that I worked out three years ago when I made the slide" just isn't good enough. Even the process of making small mistakes can be a valuable learning opportunity for students, as long as it isn't excessive.
I've only just moved to Australia so I can't really provide much political insight but there is interesting global context for this story in particular. That's that many other countries, including the U.S. have laws like this that are already in effect. Obviously the law wouldn't require all traffic content to be recorded, but rather IP logs to put internet traffic on similar footing to telephone calls. The police can look up who you talked to and when with a subpoena but no warrant.
I might be wrong, I'm basing this on similar legislation that was just passed in Canada, but that was my impression of the heavily redacted document. At least in Australia and Canada there is debate. I'm fairly certain that in the U.S. such logs are already maintained by law as well; the U.S. was used as the example that Canada was lagging behind in terms of security. Not only do U.S. ISPs maintain IP logs but traffic flowing across the American border is monitored by the NSA with almost no public supervision. And American public information is snooped and logged by the NSA. Quite frankly, the U.S. approach to monitoring it's citizens it's much more invasive, secretive and frightening.
The redacted document is a miserable failure of the current government to provide transparency, but at least the measures taken by the Australian government will be made public before they go into law; even if debate on the issue is curbed. It's far from an ideal situation, but I'd take Canadian or Australian internet laws over the NSA.
Slashdot Mirror
I hope they don't find the bodies that I buried on my Farmville.
Teaching math isn't about teaching a specific skill that everyone will use, it's about teaching how to approach problems quantitatively. At least it should be. As someone pointed out in a post further down, a lot of us don't use literary analysis in day to day life either but the reason to learn it is that learning different topics that require critical and logical thinking will arm students with better methods to approach problems with.
A physicist may well benefit a great deal from from having gone to English class in high school. Sure they only use make use of the basics, like correct spelling and grammar, every day but the style of critical thinking that is exercised in literary analysis is additional tool that they have. Similarly, math teaches and practices a way of approaching problems that other subjects don't address.
Someone who has an education in only a range of topics that is limited to their interests will be a flat, bland and incapable person.
That's absolutely right, if the market determines the going rate for bandwidth. Bandwidth is, after all, a finite resource; however, there is no competition and hence there are no market forces at play in this situation. That's where this whole can of worms came from in the first place. The whole industry is regulated because of the excessively high barriers to entry for new competitors. It's not going to be an ideal situation but it would be less bad if it was regulated well instead of being regulated by the CRTC.
Depends on where you live. If you live in Toronto, then it affects all of Canada because as far as you're concerned, Toronto = Canada.
Joking aside, Bell dominates the market in most of Ontario and Quebec. Most of the other providers in Quebec and Ontario are reselling Bell's bandwidth which means that this impacts a large portion of the internet business in Canada. Moreover, I'm sure it sets a precedent that would be relevant to resellers of Shaw or Tellus bandwidth in the West.
Shaw tends to be quite good compared to Bell but that could change. They have absurdly low data caps but they never enforce them; unlike Bell, which demands a pound of flesh for every GB over your 60 GB limit.
Let me take a run at explaining quantum computing less awkwardly than the article.
A quantum bit (qbit) may be in a 0 state, a 1 state or any linear superposition (combination) of the two, eg. 0 + i1. When measured, the outcome of the measurement can only be 0 or 1 with the probabilities of each being governed by the ratio of contributions to the qbit from the 0 and 1 components.
One qbit can usefully encode one bit of classical information (this is the point that most articles on the subject muddle up). Entangled qbits, however, also encode information into the relationship between them. More accurately, the state of the two qbits combined cannot be described by the individual states of each qbit. The number of possible states that the combined system can occupy is greater than the number of states that two unentangled qbits (or classical bits) could occupy. In other words, N entangled qbits occupy a much larger state space than 2^N, which is the state space for N classical bits.
A quantum register containing N qbits can yield an answer with, at most, 2^N bits of classical information once measured; however, the computation itself can be performed in a state space that is much larger than 2^N, hence the dramatic increase in computational power for certain algorithms. It's difficult to come up with algorithms that exploit the large quantum state space but yield a deterministic (rather than probabilistic answer). In some cases, however, even probabilistic answers may be okay if the correctness of the solution can be verified quickly with a classical algorithm and the quantum computation re-run.
Well, it's at least that often that a science journalist misrepresents a researcher's statements to make it sound like he thinks he has.
No, you really don't want to fuck with customs officers. Be civil and try to ignore violations of your rights because you will only make your situation worse.
If you want to dick around with customs officers make damn sure you have absolutely nothing that you can't import and have declared everything that you need to (did you declare the bag of peanuts you got on the plane and have in your bag?) and that you have nowhere to be for a day or so.
I'm surprised that the US doesn't already have data retention laws. It still doesn't change a lot. Phone companies and ISPs already keep logs and police routinely subpoena them. This proposal isn't as dire as the summary title makes it seem; logs of who you talk to (which IP you connect to) are already kept for a long time. A more useful law would be one that places a maximum time on the retention period, not a minimum.
It also doesn't look like he's talking about getting one useful prototype chip working in five years. He seems to mean one spin transistor five years from now. That probably puts it at decades from hitting market and only if it's a more suitable technology than all the other technologies that could, just maybe, replace the current basic transistor design.
I'd agree with that. You should make the recommendation based on which piece of software is better suited to the task. The consensus of other posters seems to be that that isn't Plone. More generally, given two identical feature sets from a commercial and an open-source application, the argument of which to use in a business setting still shouldn't fall to idealism. You'd have to look at support and frequency of updates. An open-source project with a large community may well be suitable but a smaller project might not be.
Thanks for the detailed reply! There must be a pile of unwanted non-linear effects when sending that much light through a fiber amplifier. Cross-phase modulation and four-wave-mixing must make an appearance when you're trying to keep two polarization encoded (and phase-encoded!) signals separate.
The article implies that it's easy to do, there was simply never a need before. I seriously doubt that it's a trivial thing to accomplish a four-fold increase in bandwidth on existing infrastructure.
Polarization has a habit of wandering around in fiber. Temperature and physical movement of the fiber will change how the polarization is altered as it passes through the fiber. In a trans-oceanic fiber the effect could be dramatic; the polarization would likely wander around with quite a high frequency. This would need to be corrected for by periodically sending reference pulses though the fiber so that the receivers could be re-calibrated. Not too difficult, but any inaccessible repeaters would still need to be retrofitted. I also don't know if in-fiber amplifiers are polarization maintaining. They rely on a scattering process that might not be.
Phase-encoding has similar problems. Dispersion, the fact that different frequencies travel at different velocities (this leads to prisms separating white light into rainbows), will distort the pulse shape and shift the modulation envelope with respect to the phase. You either need very low dispersion fibers, and they already need to use the best available, or have some fancy processing at a receiver or repeater. Adding extra phase encoding simply implies that the current encoding method (probably straight-up, on-off encoding) is inefficient. That's not necessarily lack of foresight, that's because dense encoding is probably really hard to do in a dispersive medium like fiber. Again, it's not a trivial drop-in replacement.
The article downplays how hard these problems are. It implies that the engineers simply didn't think it through the first time around, but that's far from the case. A huge amount of money and effort goes into more efficiently encoding information in fiber. There probably is no drop in solution, but very clever design in new repeaters and amplifiers might squeeze some bonus bandwidth into existing cable.
It's probably two of them. Two degrees of freedom from polarization, two from phase.
If your information is carried on an amplitude modulated sine wave, you recover it by demodulating with another sine wave. Demodulating with an orthogonal function, cosine, yields nothing. So you can pack a second carrier with a cosine phase in there and then demodulate each with the correct phase to extract the modulation signal. I don't know much about how much cross-talk there would be but probably, in theory, as long as the modulation frequency (on the order of GHz) is slow compared to the carrier frequency (hundreds of THz), it's not too bad.
The Laws of Physics don't form a complete, formal logical system nor do they attempt to. The set of mathematical axioms used to describe the physical world doesn't need to be complete in order to be logically coherent; it can be proven using axioms that lie outside the set and still be useful and coherent.
There is a temptation to apply elegant theorems like Godel's to situations that they do not apply to and this is one of those cases. The Laws of Physics do not, in the sense of a formal system, attempt to prove themselves and hence Godel's theorem does not apply.
The work is related to trapping single, neutral atoms efficiently. Trapping techniques for bulk quantities of charged particles tend to be simpler. Slowing down energetic particles is probably tough, but doesn't relate to this research.
Photographs of trapped single atoms abound; they're just not that interesting. The atom will scatter light from the trapping beams and the scattered light can be easily imaged onto a camera. In fact, imaging is often used to characterize the trap. The atom just shows up as a blurry dot with the size of the blur being determined by the diffraction limit of the light or perhaps the tightness of the confinement. There's certainly no internal structure that would be resolvable.
Or reasonable tab overflow handling.
I would imagine that it would be similar legally to applying mods or cracks to game consoles or iPhones. Breaking a digital lock is, in itself, illegal in some countries and that would certainly qualify. Beyond that, I've never really understood the argument that you can't do what you want with your phone/console/chip.
My question is how is the patch applied? Is it a firmware update on the processor itself? (Do processors have firmware to update?) Bios update? If it's in the operating system, what does the processor look like to a Linux kernel and how would one unlock it in that case? No doubt someone here has a better idea of how it will work than I do.
Let me provide some context. This research group specializes in manufacturing arbitrary waveguide structures on chips, then coupling particular quantum states of light into them. The idea is to turn a large optical table worth of mirrors into a tiny chip. What they have done here, is allowed a two photon input state to interfere with itself in the waveguide structure.
While interesting technically, it isn't exactly a huge leap forward because the interaction is linear. What's needed for deterministic quantum computation with light is a very non-linear process. The waveguide structure can replace a large number of mirrors and compact the optics into a tiny space but, at the end of the day, mirrors aren't all that interesting for quantum computation. It is, however, worthwhile because of the impressive miniaturization and the technical challenge of working with quantum light in such tiny structures. A strong non-linear component will be needed for true optical quantum computation, but chips like these show a lot of promise for handling a lot of state preparation and measurement.
It's a pretty damn big loophole. They used a 1 mW beam which is about as powerful as a laser pointer. That's many orders of magnitude larger than a single-photon level signal and should be very easy to detect. Not noticing a milliwatt of light hitting the detector in a quantum scheme is something like leaving a key written in plain text on a sticky note on your monitor and being shocked when your key is "hacked."
It certainly means that we both spend too much time here.
before I change my sig. I like this one.
I'm sure there aren't many companies that would put up with that at all. That's why it would be so effective; not many ISPs would remain in business if they failed to protect their customers from such shut-offs.
Exactly. It's altogether too easy for professors to use PowerPoint slides as a crutch. There's no substitute for making a derivation in class with the students following along in their notebooks. "Here's a derivation that I worked out three years ago when I made the slide" just isn't good enough. Even the process of making small mistakes can be a valuable learning opportunity for students, as long as it isn't excessive.
I've only just moved to Australia so I can't really provide much political insight but there is interesting global context for this story in particular. That's that many other countries, including the U.S. have laws like this that are already in effect. Obviously the law wouldn't require all traffic content to be recorded, but rather IP logs to put internet traffic on similar footing to telephone calls. The police can look up who you talked to and when with a subpoena but no warrant.
I might be wrong, I'm basing this on similar legislation that was just passed in Canada, but that was my impression of the heavily redacted document. At least in Australia and Canada there is debate. I'm fairly certain that in the U.S. such logs are already maintained by law as well; the U.S. was used as the example that Canada was lagging behind in terms of security. Not only do U.S. ISPs maintain IP logs but traffic flowing across the American border is monitored by the NSA with almost no public supervision. And American public information is snooped and logged by the NSA. Quite frankly, the U.S. approach to monitoring it's citizens it's much more invasive, secretive and frightening.
The redacted document is a miserable failure of the current government to provide transparency, but at least the measures taken by the Australian government will be made public before they go into law; even if debate on the issue is curbed. It's far from an ideal situation, but I'd take Canadian or Australian internet laws over the NSA.