No, condensation occurs when the temperature of air drops below the dew point. The air is what's containing the moisture. (Yes, introducing cold objects to warm air causes condensation on them, too.)
Placing a room-temperature laptop in a refrigerator is a mistake. It will accumulate condensation going in as it cools down, and possibly coming back out as the cold laptop contacts warm air.
There are some good strategies to generate a ton of false positives, making the system useless. However, after a couple of people in a day with no reason to be emitting radiation and seemingly not carrying anything suspicious are found, they'd probably shut down the border crossing and call in investigators. There aren't many natural situations that would cause a lot of false positives, so if they catch a ton, they can suspect someone has planted them there to foil the system.
You call it whatever you want, I suppose. The general term is a digit (for any base). But you just convert base-2 numbers into base-3 for communication, and then back -- similar to how a computer converts our base-10 numbers into binary before using them.
They just mean that their objects can encode one of three states. The amount of information, in "bits", a state encodes is log2(number of possible states), and log2(3) ~= 1.58. By the same token, a single decimal digit stores 3.32 bits.
I think he's upset that he took CS classes, not vocational training classes. When will people learn that learning how to program isn't what CS is?
Frankly, understanding how things work is really important in programming. If you're working with a database without an understanding of the mechanics of its storage, you're likely to do it badly. If you don't understand how the cryptographic algorithms you're using work, you definitely shouldn't be trusted with a crypto library.
Which eggheads are you talking about? I certainly wouldn't call the policy-makers eggheads. The people I'm talking about are those that design and test the radiological detection equipment and those that track the world's "missing" radioactive material.
These guys know full well there are other means of attack than nuclear devices, and most of them are much easier to implement and thus more likely. Nuclear devices, however, have a much higher cost associated with not detecting them. (The cult's subway sarin attack in Japan would not have been nearly as devastating as a dirty bomb in Tokyo.) They've also determined there's a distinct possibility that terrorists could use these devices. That doesn't mean anyone is ruling out and not guarding against other potential avenues of attack, but usually you don't mention those in an article or discussion about anti-nuclear measures.
They're also familiar with many low-tech ways around these detectors. There are, admittedly, lots of low-tech ways around them, some of which have counters, some of which don't. (As an example, there's a great photo of a border station where vehicles have clearly simply driven around the scanner.)
I'm not really a conspiracy theorist here. Say what you will about the government wanting to keep people afraid to do whatever its nefarious schemes are. You don't need to build radiological detectors at border crossings to do that. Further, we're talking about a matter where, as far as I can tell, nobody's "basic rights" have been taken away. This system has plenty of false positives, yet nobody's been imprisoned because of it. As far as I know, you have no right when entering the country to deny a search by customs and border security, particularly if they have a good reason to search (such as emitting radiation beyond the level expected in most vehicles). So, while accusing the government of trying to take away your liberties and keep you afraid may be true, it's no more relevant to the discussion than the fact that your attempt to make they government into a rights-stealing bogeyman.
Most of this scanning is done only on a fraction of the crossings -- although low-energy X-ray scanners are fast, they're just not that cheap.
Of course, there's a way to get around just about any of these systems. If you're smuggling nuclear material, though, remember that having enough to have redundant supplies is more expensive, and the people in the one truck that gets caught had better have absolutely no link to the other two trucks.
No, the eggheads are quite familiar with exactly how effective they are and with potential ways of circumventing the security. While it's nice to pretend you're far more clever than they, it's not so. If you happen to go to a physics meeting where they're doing presentations on radiological detectors, they're more than happy to lay out in detail the failings of the system.
Many border monitoring stations do just that, but you should assume that a potential terrorist would know if they were all fake, making the expenditure of creating the fake detectors a waste.
You understand this has both caught and failed to catch zero dirty bombers, yes? I think we should know from criticism when the administration says there hasn't been another terrorist attack that the rock-that-keeps-away-bears argument is flawed.
The system as a whole gets a couple of false positives a day, roughly. The monitoring isn't that expensive (many of the border detectors are fake -- or at least, were a few years ago), but manually examining false positives is expensive.
One of the more entertaining false-positive triggers is cat litter, which in truckload quantities contains enough radioactive material to trigger a detector.
Actually, if you're talking about transporting bomb material, existing border radiation detectors are already sensitive enough to detect radioactive isotopes shielded by truck-sized load of steel. (Another possibility is to simply hide the material in a truckload of scrap iron.)
The Heisenberg uncertainty principle isn't really what you mean. Heisenburg states that if two variables (such as position and momentum) have a particular relationship, then you cannot simultaneously measure both of them to arbitrary accuracy. (It places specific limits on the accuracy to which you can measure them.)
To make a long story short, though, both quantum entanglement and the collapse of wavefunctions due to measurement are experimentally-confirmed fact, and small quantum computers have been built.
Your personal opinion sounds like the opinion of many physicists in early quantum mechanics days. It's called a hidden variable, meaning that there is a deterministic process going on that we can't get at, and that superposition is just a convenient statistical model. This was more or less summarized in the EPR paradox. The answer to this was Bell's theorem, which showed, again cutting a long story short, that whether superposition and entanglement were "real" or just hiding some deterministic hidden variable could be determined experimentally. This has been done, and superposition and entanglement are real. (Though Einstein would be happy to know that despite the apparent "spooky action-at-a-distance" of entangled particles, they cannot be used to transmit information faster than lightspeed.)
No, this is why you don't use secret key system like 3DES or AES. Essentially, the number of keys you need to distribute scales with the number of pairs of communicating parties. If you have N parties all wanting to communicate with each other, that's O(N^2) keys. This is fairly unlikely, though. If you have, say, S servers (banks, etc.) and C clients, it's more like O(S*C) -- though a client-server pair may separate keys for different tasks.
One-time pads cannot be reused. That's why they're called one-time. This means that the quantity of one-time pad data that needs to be securely shared between two communicating parties is equal to the quantity of data they want to exchange. Say a bank transaction involves communicating 1k of data. The bank needs to give you -- securely -- 1k of OTP data per transaction you'll want to make. Generally, this is inconvenient. Since real one-time pads are unbreakable, this just means the vector for attack is moved somewhere else -- most likely, how you communicate the OTP data. (If someone can impersonate you to a bank employee and get a few transactions' worth of pad, the security of a one-time pad is irrelevant. If you use an existing cryptographic algorithm to exchange one-time pad data, you're wasting time -- simply transmit your real data using this algorithm.) One-time pads have been used, but only in a few specific situations. In general, they're not useful.
Applying a one-time pad to data is generally done by simply XORing the pad (which consists of random bits) with the data. Reusing a one-time pad is incredibly easy to break.
It appears from the first comment on the post that it's likely that this post isn't really accurate. Shor's factoring algorithm is O(k) in number of qbits and O(k^3) in number of operations. This doesn't mean that the number of gates in the quantum computer is O(k^3), it means that the time it takes to execute the algorithm is O(k^3). It appears this discrepancy may be a result of not agreeing on terminology. I haven't checked this out thoroughly, but glancing at my copy of Mermin's "Quantum Computer Science" confirms that it's k^3 in time, and only k in space.
While it's clear a quantum computer won't be breaking your RSA keys any time soon, there's a big difference between remarking that a 4096-bit key will require "billions" of qbits and the more correct claim that it will require thousands of qbits (at least 20k qbits).
My reading of that is that the KDE 4 version is new and in development, so a) not all features in the KDE 3 version are necessarily present or working yet b) they're not offering commercial support for it yet.
This misstatement reminds me of a story. Almost all electricity is produced by doing something that produces heat. Heat heats up water, steam runs a turbine, turbine and magnets make electricity. So why do we have electric hot-water heaters, when we could've just piped the hot water to our homes? After all, we pipe cold water to our homes.
Thermal and electrical insulators aren't perfect insulators, they just have very poor conductance. However, the difference between a thermal conductor and a thermal insulator is small. The difference between an electrical insulator and an electrical conductor is very large. So if you're shipping something over long distances, heat is very lossy, but electricity is not very lossy (even if you include the fact that your carrier for electricity has nonzero resistance).
Now, when the stuff you're insulating is, say, hot coffee or ice water in a room-temperature environment, really good thermal insulation is quite effective. However, keeping things cold even at liquid nitrogen temperatures isn't that easy. (Liquid nitrogen is popular as a lab temperature because it's fairly cheap and easy to maintain.) Even excellently-insulated systems at those temperatures require a bath of liquid nitrogen and boil off quite a bit of it. Maintaining that kind of a heat sink to compensate for thermal conductivity is difficult and expensive for large systems.
Pressure, on the other hand, is an entirely different beast. Unfortunately, most people here seem to be thinking of gases under pressure, which you can sort of visualize as being similar to heat or electricity (mostly escaping from the weak points in your "insulation", being difficult to maintain very high pressures, etc.). Pressure in solids, however, doesn't really work quite the same, and generating and maintaining very high pressures within a solid is not necessarily unfeasible.
Problems with your statement: * Misuse of "proven". Try "demonstrated". * Inclusion Congress and DMCA, which has nothing to do with this. * White-hat hackers lack particular resources that are very useful in finding criminals. Most of them aren't too keen on getting arrested, whereas law enforcement doesn't really need to worry about this. * You can't "block piracy".
From my experience with "cyber cops", they won't give two shits about copyright infringement (isn't that a civil matter anyway?). Current law enforcement focuses on some identity theft (usually not a lot of computer investigation involved there), child pornography, and bank theft (in its many forms). Larger criminal organizations, which make as much use out of the Internet as they can, are harder to do much about because of jurisdictional boundaries. As a result "cyber cops" have been putting together organizations to a) share useful information and techniques b) have more effective cross-jurisdictional investigations.
Further, the feature of being able to verify your vote after it is cast is a feature that doesn't exist in the current voting system. I flip some toggles, and can verify which toggles I've flipped, but I have no guarantee (just by looking at the thing) regarding what happens after the lever is pulled.
Re:really, i didn't make it up
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"...but every person has an abolute right to not be even "incidentally exposed" to some things..."
That's not true. You have a certain right to not be forced to be subjected to objectionable material (the corollary to the right to free speech is the right to walk away), but this doesn't extend to any claim that public resources must be restricted to conform to some mutually-agreed-upon idea of "acceptable". If the option to turn off the television is reasonable, then your right to not listen/view is satisfied.
Don't tack the word "absolute" onto a discussion of rights just because you happen to think that right is particularly important.:p
Certainly true. To an extent, though, the purpose of these regulations such as those the FCC enforces (and those that various cable networks self-enforce) are to supply parents with information about programming they're not already familiar with. I suppose some parents view it as "too late" if their children accidentally see something unexpected on television (such as, for example, cooking and serving a human placenta on a daytime food show). Of course, this doesn't apply to programming that you're already familiar with and that has a consistent quality. (I'd mostly be concerned about younger children, and children's programming certainly falls into this category.)
I don't agree with that mindset -- incidental exposure isn't too damaging -- but the FCC regulations aren't entirely intended simply to prevent children from viewing objectionable content while removing the need from parental supervision.
There's not much wrong with steganography of encrypted data, particularly if the data in the covert channel would have been statistically similar to random data anyway.
Most image steganography isn't that great, though, and steganography by a well-known means of cleartext data is fairly pointless.
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No, condensation occurs when the temperature of air drops below the dew point. The air is what's containing the moisture. (Yes, introducing cold objects to warm air causes condensation on them, too.)
Placing a room-temperature laptop in a refrigerator is a mistake. It will accumulate condensation going in as it cools down, and possibly coming back out as the cold laptop contacts warm air.
There are some good strategies to generate a ton of false positives, making the system useless. However, after a couple of people in a day with no reason to be emitting radiation and seemingly not carrying anything suspicious are found, they'd probably shut down the border crossing and call in investigators. There aren't many natural situations that would cause a lot of false positives, so if they catch a ton, they can suspect someone has planted them there to foil the system.
You call it whatever you want, I suppose. The general term is a digit (for any base). But you just convert base-2 numbers into base-3 for communication, and then back -- similar to how a computer converts our base-10 numbers into binary before using them.
They just mean that their objects can encode one of three states. The amount of information, in "bits", a state encodes is log2(number of possible states), and log2(3) ~= 1.58. By the same token, a single decimal digit stores 3.32 bits.
I think he's upset that he took CS classes, not vocational training classes. When will people learn that learning how to program isn't what CS is?
Frankly, understanding how things work is really important in programming. If you're working with a database without an understanding of the mechanics of its storage, you're likely to do it badly. If you don't understand how the cryptographic algorithms you're using work, you definitely shouldn't be trusted with a crypto library.
Which eggheads are you talking about? I certainly wouldn't call the policy-makers eggheads. The people I'm talking about are those that design and test the radiological detection equipment and those that track the world's "missing" radioactive material.
These guys know full well there are other means of attack than nuclear devices, and most of them are much easier to implement and thus more likely. Nuclear devices, however, have a much higher cost associated with not detecting them. (The cult's subway sarin attack in Japan would not have been nearly as devastating as a dirty bomb in Tokyo.) They've also determined there's a distinct possibility that terrorists could use these devices. That doesn't mean anyone is ruling out and not guarding against other potential avenues of attack, but usually you don't mention those in an article or discussion about anti-nuclear measures.
They're also familiar with many low-tech ways around these detectors. There are, admittedly, lots of low-tech ways around them, some of which have counters, some of which don't. (As an example, there's a great photo of a border station where vehicles have clearly simply driven around the scanner.)
I'm not really a conspiracy theorist here. Say what you will about the government wanting to keep people afraid to do whatever its nefarious schemes are. You don't need to build radiological detectors at border crossings to do that. Further, we're talking about a matter where, as far as I can tell, nobody's "basic rights" have been taken away. This system has plenty of false positives, yet nobody's been imprisoned because of it. As far as I know, you have no right when entering the country to deny a search by customs and border security, particularly if they have a good reason to search (such as emitting radiation beyond the level expected in most vehicles). So, while accusing the government of trying to take away your liberties and keep you afraid may be true, it's no more relevant to the discussion than the fact that your attempt to make they government into a rights-stealing bogeyman.
Most of this scanning is done only on a fraction of the crossings -- although low-energy X-ray scanners are fast, they're just not that cheap.
Of course, there's a way to get around just about any of these systems. If you're smuggling nuclear material, though, remember that having enough to have redundant supplies is more expensive, and the people in the one truck that gets caught had better have absolutely no link to the other two trucks.
They use a low-energy exterior x-ray scanner on trucks. If it doesn't penetrate into the shipping container, they're investigated further.
No, the eggheads are quite familiar with exactly how effective they are and with potential ways of circumventing the security. While it's nice to pretend you're far more clever than they, it's not so. If you happen to go to a physics meeting where they're doing presentations on radiological detectors, they're more than happy to lay out in detail the failings of the system.
Many border monitoring stations do just that, but you should assume that a potential terrorist would know if they were all fake, making the expenditure of creating the fake detectors a waste.
You understand this has both caught and failed to catch zero dirty bombers, yes? I think we should know from criticism when the administration says there hasn't been another terrorist attack that the rock-that-keeps-away-bears argument is flawed.
The system as a whole gets a couple of false positives a day, roughly. The monitoring isn't that expensive (many of the border detectors are fake -- or at least, were a few years ago), but manually examining false positives is expensive.
One of the more entertaining false-positive triggers is cat litter, which in truckload quantities contains enough radioactive material to trigger a detector.
Actually, if you're talking about transporting bomb material, existing border radiation detectors are already sensitive enough to detect radioactive isotopes shielded by truck-sized load of steel. (Another possibility is to simply hide the material in a truckload of scrap iron.)
The Heisenberg uncertainty principle isn't really what you mean. Heisenburg states that if two variables (such as position and momentum) have a particular relationship, then you cannot simultaneously measure both of them to arbitrary accuracy. (It places specific limits on the accuracy to which you can measure them.)
To make a long story short, though, both quantum entanglement and the collapse of wavefunctions due to measurement are experimentally-confirmed fact, and small quantum computers have been built.
Your personal opinion sounds like the opinion of many physicists in early quantum mechanics days. It's called a hidden variable, meaning that there is a deterministic process going on that we can't get at, and that superposition is just a convenient statistical model. This was more or less summarized in the EPR paradox. The answer to this was Bell's theorem, which showed, again cutting a long story short, that whether superposition and entanglement were "real" or just hiding some deterministic hidden variable could be determined experimentally. This has been done, and superposition and entanglement are real. (Though Einstein would be happy to know that despite the apparent "spooky action-at-a-distance" of entangled particles, they cannot be used to transmit information faster than lightspeed.)
No, this is why you don't use secret key system like 3DES or AES. Essentially, the number of keys you need to distribute scales with the number of pairs of communicating parties. If you have N parties all wanting to communicate with each other, that's O(N^2) keys. This is fairly unlikely, though. If you have, say, S servers (banks, etc.) and C clients, it's more like O(S*C) -- though a client-server pair may separate keys for different tasks.
One-time pads cannot be reused. That's why they're called one-time. This means that the quantity of one-time pad data that needs to be securely shared between two communicating parties is equal to the quantity of data they want to exchange. Say a bank transaction involves communicating 1k of data. The bank needs to give you -- securely -- 1k of OTP data per transaction you'll want to make. Generally, this is inconvenient. Since real one-time pads are unbreakable, this just means the vector for attack is moved somewhere else -- most likely, how you communicate the OTP data. (If someone can impersonate you to a bank employee and get a few transactions' worth of pad, the security of a one-time pad is irrelevant. If you use an existing cryptographic algorithm to exchange one-time pad data, you're wasting time -- simply transmit your real data using this algorithm.) One-time pads have been used, but only in a few specific situations. In general, they're not useful.
Applying a one-time pad to data is generally done by simply XORing the pad (which consists of random bits) with the data. Reusing a one-time pad is incredibly easy to break.
It appears from the first comment on the post that it's likely that this post isn't really accurate. Shor's factoring algorithm is O(k) in number of qbits and O(k^3) in number of operations. This doesn't mean that the number of gates in the quantum computer is O(k^3), it means that the time it takes to execute the algorithm is O(k^3). It appears this discrepancy may be a result of not agreeing on terminology. I haven't checked this out thoroughly, but glancing at my copy of Mermin's "Quantum Computer Science" confirms that it's k^3 in time, and only k in space.
While it's clear a quantum computer won't be breaking your RSA keys any time soon, there's a big difference between remarking that a 4096-bit key will require "billions" of qbits and the more correct claim that it will require thousands of qbits (at least 20k qbits).
My reading of that is that the KDE 4 version is new and in development, so a) not all features in the KDE 3 version are necessarily present or working yet b) they're not offering commercial support for it yet.
This misstatement reminds me of a story. Almost all electricity is produced by doing something that produces heat. Heat heats up water, steam runs a turbine, turbine and magnets make electricity. So why do we have electric hot-water heaters, when we could've just piped the hot water to our homes? After all, we pipe cold water to our homes.
Thermal and electrical insulators aren't perfect insulators, they just have very poor conductance. However, the difference between a thermal conductor and a thermal insulator is small. The difference between an electrical insulator and an electrical conductor is very large. So if you're shipping something over long distances, heat is very lossy, but electricity is not very lossy (even if you include the fact that your carrier for electricity has nonzero resistance).
Now, when the stuff you're insulating is, say, hot coffee or ice water in a room-temperature environment, really good thermal insulation is quite effective. However, keeping things cold even at liquid nitrogen temperatures isn't that easy. (Liquid nitrogen is popular as a lab temperature because it's fairly cheap and easy to maintain.) Even excellently-insulated systems at those temperatures require a bath of liquid nitrogen and boil off quite a bit of it. Maintaining that kind of a heat sink to compensate for thermal conductivity is difficult and expensive for large systems.
Pressure, on the other hand, is an entirely different beast. Unfortunately, most people here seem to be thinking of gases under pressure, which you can sort of visualize as being similar to heat or electricity (mostly escaping from the weak points in your "insulation", being difficult to maintain very high pressures, etc.). Pressure in solids, however, doesn't really work quite the same, and generating and maintaining very high pressures within a solid is not necessarily unfeasible.
Problems with your statement:
* Misuse of "proven". Try "demonstrated".
* Inclusion Congress and DMCA, which has nothing to do with this.
* White-hat hackers lack particular resources that are very useful in finding criminals. Most of them aren't too keen on getting arrested, whereas law enforcement doesn't really need to worry about this.
* You can't "block piracy".
From my experience with "cyber cops", they won't give two shits about copyright infringement (isn't that a civil matter anyway?). Current law enforcement focuses on some identity theft (usually not a lot of computer investigation involved there), child pornography, and bank theft (in its many forms). Larger criminal organizations, which make as much use out of the Internet as they can, are harder to do much about because of jurisdictional boundaries. As a result "cyber cops" have been putting together organizations to a) share useful information and techniques b) have more effective cross-jurisdictional investigations.
Further, the feature of being able to verify your vote after it is cast is a feature that doesn't exist in the current voting system. I flip some toggles, and can verify which toggles I've flipped, but I have no guarantee (just by looking at the thing) regarding what happens after the lever is pulled.
"Myopic Books, a used book store in Chicago..."
What do they know? They're shortsighted.
"...but every person has an abolute right to not be even "incidentally exposed" to some things..."
:p
That's not true. You have a certain right to not be forced to be subjected to objectionable material (the corollary to the right to free speech is the right to walk away), but this doesn't extend to any claim that public resources must be restricted to conform to some mutually-agreed-upon idea of "acceptable". If the option to turn off the television is reasonable, then your right to not listen/view is satisfied.
Don't tack the word "absolute" onto a discussion of rights just because you happen to think that right is particularly important.
I suspect he doesn't understand how the digital broadcast conversion works.
Certainly true. To an extent, though, the purpose of these regulations such as those the FCC enforces (and those that various cable networks self-enforce) are to supply parents with information about programming they're not already familiar with. I suppose some parents view it as "too late" if their children accidentally see something unexpected on television (such as, for example, cooking and serving a human placenta on a daytime food show). Of course, this doesn't apply to programming that you're already familiar with and that has a consistent quality. (I'd mostly be concerned about younger children, and children's programming certainly falls into this category.)
I don't agree with that mindset -- incidental exposure isn't too damaging -- but the FCC regulations aren't entirely intended simply to prevent children from viewing objectionable content while removing the need from parental supervision.
It's a lot easier to edit those fields than to properly redo all the lighting so that a lighting-analysis program can't detect it.
There's not much wrong with steganography of encrypted data, particularly if the data in the covert channel would have been statistically similar to random data anyway.
Most image steganography isn't that great, though, and steganography by a well-known means of cleartext data is fairly pointless.