That sounds rather stupid. Why only test for "on" or "off" when you can test for any of the states?
Two points: what other states, and how do you propose we measure them? Quantum bits will typically have only the 1/on and 0/off states, by design - partly because it meshes well with our classical computing methods, and partly because most make use of concepts like spin which are naturally in up/down or the like. When isolated, they evolve into a state expressed by a|0> + b|1>, where a and b are the probability that you will observe the 0 state or the 1 state, respectively. This superposition state is impossible to observe, since the wavefunction collapses into one or the other on observation, so we can only observe either the 1 or the 0. More generally, you have a state for the entire register which is the superposition of every possible 'classical' state, with individual probabilities of being observed when you check the register of a, b, c and so forth.
Also, your post makes little since, everything is observed, which is why it exists, just because it isent observed by humans dosent mean its not observed,
This is very true, in general, and is the very reason why quantum computing is hard. The qubits have to be completely isolated from everything except the read/write mechanism, so that these particles will only be observed by humans, and nothing else, otherwise many of the requirements to make a quantum computer effective cannot be reasonably achieved.
I do believe you're mistaken. Quantum bits are exactly like regular bits in their possible observable states - that is, they are either "on" or "off" when observed. The interesting part of quantum computing comes from the fact that, when they're not being observed, they exist in a superposition of both "on" and "off" states. Now, if you put 8 of these bits together, you have a 'qbyte' which, while when it's observed it can only represent the same range as a regular byte, can be used in calculations representing every single possible permutation of the data at once - i.e. every number from 0 through 255. Each bit you add doubles the number of states you can simultaneously test using this superposition property - this is what the GP meant when he said that quantum computing scales as 2^n.
The chart is one which compares active subscribers, and for that goal, "Monthly fee" is an extremely sensible metric, methinks. Moreover, quoth the FAQ:
1. Why isn't [MMOG_NAME] listed?
There are four main reasons why a particular game isn't listed in the charts:
a) The game in question isn't really a MMOG, at least by my reckoning. Games like Diablo II and Phantasy Star Online fall into this category. Guild Wars developers say in their own FAQ that they do not consider their game a MMOG; in addition, it doesn't charge a monthly fee (see below). Please don't email me trying to insist otherwise; I'm not likely to be convinced.
b) The game in question is free and/or doesn't charge a regular monthly fee. Games like Furcadia, Magic: the Gathering Online, and Project Entropia are good examples; these games are normally free to play, but some players can also pay a variable amount to access additional content in the game. This makes it almost impossible to come up with a number comparable to monthly subscribers in other games.
Both points relavent in general, the most significant bit is emphasised by me.
Okay, so because a theory (or more an idea or almost a philosiphy) cannot be disproven, it becomes a disaster for modern science?
Well, yes, because that's not how science works. Theories have to be put forward which make predictions which can be meaningfully tested. If there is no way to actually test it, then it is, in effect, impossible to develop - by definition it cannot be wrong, and therefore is effectively complete, and science is 'finished', more or less. If such an idea ends up being the dominant trend, then yes, it would be something of a disaster.
I suppose we should stop looking for what started the universe, since we can't disprove the existance of God or anything. What a load of BS.
Would you class the statement "Everything happens because God says so" as scientific? I would hope not - such a statement is inherently impossible to scrutinise or critique, as "God did it" is, in this theory, a perfectly valid response. Science does not advance by pursuing ideas of that sort, but rather putting forward testable theories, and working out ways to stress them and see if their predictions hold, and refining them as a result.
That some ideas cannot be disproven is not a problem for science - instead we content ourselves with studying those that can be.
Mouses has somehow, inexplicably, became viewed an acceptable substitute for mice in computing circles.
From asking various people who use it their reason for doing so, I get answers ranging from "dunno", though fake origins of the word "mouse" in computing terms as some sort of acronym, around claims that the inventor chose that name (as far as I can tell, he doesn't care), to the suggestion that "mice" could lead to confusion with the furry creature (although why exactly it does so more than "mouse" escapes me).
All in all, it seems rather pointless to me, but it's pretty much common usage in some places now, so seems pointless to complain about it.
If you get a post like "they should do X like they it in CS" (...) then there really isn't much you can do.
But what if they should do X like they do it in CS/WoW/whatever other game you hate? What if it is a really valid suggestion, even for this different game? You should judge an idea based on its merits, not on it's origin.
Yes, TFA is incorrectly worded. They applied for the 2155 to 2175MHZ band.
Interestingly, they reason they're offering the government money is not as a 'kick-back', but to actually pay for the allocation, since they aren't offering any money to purchase it up-front.
"Territory" is commonly used to denote the regions of release which games are typically separated into - the big ones being Japan, the US, and the UK/Europe (sometimes the last two go together, sometimes not). I've seen it used in both English and American publications quite a bit, it's pretty much standard usage.
It would be cool to artificially vary the viscosity of the water with polymers, or add salts to increase specific gravity to note the affect on the pattern properties.
They beat you to it - they also did the experiment with ethylene glycol (about 15 times the viscosity of water). The same effect was observed, but only for low-order polygons. Not a huge difference in required frequencies over most depths, although the curves are rather less smooth than the ones obtained for water (presumably due to vorticies and so forth arising from the higher viscosity)
Well, if you have waves in the bucket, and the circumference of the hole is a multiple of that wavelength, then it's very natural that this phenomenon should happen.
In that situation, there would be perfect axial symmetry as these wavelengths would be identical in all directions, giving a fixed circular standing wave pattern once the flow stabilised (given a symmetric bucket, obviously). However, in this case, we have a breakdown in axial symmetry, and instead have slowly rotating geometric shapes instead.
But seriously, what if in the ocean the waterflow is spinning very hard itself under certain conditions, wouldn't that be a possible explanation for the disappearances in the Bermuda Triangle?
Not really, no - whirlpools and the like are a whole other kettle of fish than the result presented here. Surface deformations of rotating water and the like have been known about for a long time (and I'm sure have been postulated as an explanation in the past), this is just an interesting little anomoly which turns up under certain particular conditions. Given this is highly dependant on things like the container shape, water depth and so forth, I don't think a direct analog would be observable in the real world.
They could try to get him on unauthorized use a computer system, but the precedent there would be bad.
Do you really want to go to jail because you guessed a URL? I know I often have tried to get around sites with bad navigation by crafting the URL, I don't consider that hacking.
How often does your crafting of a URL cost a company monies on the order of maybe ten thousand dollars? (guesstimate based off how much he "withdrew" from his account after they closed it)
Very different situations - lots of things are ignored when they do no harm, but if he loses his case, he will be setting himself up nicely for Linden to smack him down a bit.
It's more than just violating the EULA - he 'hacked' (yes, I know it's not exactly the right word, but you just know it'd be used if it ever came to court) the system to enable him to circumvent controls (minimum bids, probably some degree of supervision from someone at the company) to get property which, if the system was working correctly, he would have paid many times more for.
Compare it to some types of cheque fraud - the system (or teller or what have you, depending on the nature of the scam) is fooled into completing a transaction by the fraudster's manipulation of the normal procedures. Definately illegal, and very similar to this - due a flaw in the automated nature of the auction processing, he was able to complete transactions which should never have been allowed in the normal scheme of things. This wasn't a bumbling rube finding a good deal, this was someone manipulating the system with a clear intent to turn a sizable profit from it.
This basically comes down to a battle between "They should have been more careful" and the fact that he maliciously interfered with their system in an unintended way for personl gain. Given the company will probably be cheerfully loading up on words like "Fraud", "hacking", "Terms of Use" in any arguments they submit, he'll probably get steamrolled pretty quickly since courts like to pounce on words like that.
My preferred approach is not to use the term "group velocity" due to these ambiguities. But this is/., and I was in a rush, and at least I sparked a discussion that has hopefully clarified matters for the average reader.
Quite understandable, but I have gotten into a bit of a habit of defending scientific arguments from people who are criticising the result based on some misremembered bit of knowledge from their past (being the token scientist in my family, it typically falls to me to explain/defend anything which has caught people's attention and which they feel is intersting/pointless), so I felt compelled to butt in here too.
It seems that the real point of this experiment is that (should they be able to produce a useful pulse with the properties they desire) it will actually be able to test the mechanism which is speculated to cause this effect, as well as simply observing the result, although that point isn't really mentioned much in the article. You're quite right that it will probably be another one of the "Established theory wins again!" situations, but hey, you gotta check to know for sure, right?
Very true - although I had understood that the issue with the phase velocity was not that it was expressly limited by c (as in could be measured to be c), but that in materials where it would have been greater than c, it loses physical significance and can't be meaningfully observed, for obvious reasons. Of course then there's the question of whether or not it has any value at all then and you get bogged down in semantics.
I think the real point which illustrates the issues in describing this is illustrated a few times in that quotes you posted:
the phase velocity cannot be determited experimentally and must therefore be considered to be void of any direct physical significance.
If the medium is not strongly dispersive...
These values are tools used to study a particular subset of waves - it's a very large, very useful section, but in cases where we have all sorts of quantum mechanical effects and extreme numbers coming into play, their usefulness and even their meaning is diluted somewhat, which leaves any attempt to describe them up for all these various little bits of nitpicking.
But hey, nitpicking is one of the funnest bits of science, right?
What if there exists a humanly imperceptible medium through which light travels?
You know, I can't quite decide if this is going for humour or not - the 'Ether' which light propagated through was the major player in the theory of light for hundreds of years. However, as we learnt more about light, the requirements on the nature of the ether so that it existed, could support light waves as we observe them, and still not be picked up by all the experiments done to attempt to find it required it to have a simply ludicrous selection of physical properties, which are often self-contradictory or conflict with other ideas to the extent that it's been abandoned by all but a few obsessives.
However, there is an interesting little theory I read once - due to the uncertainty principle photons, electrons and other particles are popping in and out of existance all the time. Many real, observed forces are interpreted in these terms. The question is, do they affect regular light propagation? And if so, if you arrange a cavity (a very small one, obviously), you can restrict the particles can form inside it (as a result of the boundary conditions imposed on their wavefunction by the cavity) and hence reduce the number of particles which interact with the light, and hence get a real, measureable, and meaningful above-c speed.
Of course it's just an idea, I don't think I've ever seen it ever put forward in any serious forum, it's a very minor detail, and I must confess I've never really put more thought into it than relating the description of it than I am right now. But still, it's an amusing idea, I think.
It is impossible to get group velocities that are faster than c (the speed of light in a free vacuum, a universal constant.) Information travels with the group velocity.
This statement, and your criticism of the experiment, is based on out of date (or simply ill-researched) information, and it worries me that it got modded up to 5.
In this case, the group velocity is indeed faster than the speed of light - the form of the wavepacket peak (the speed of which is the definition of the group velocity [1]) travels through the fibre almost instantaneously, much faster than c. This is one of the two things about this experiment is interesting, as by the old-fashioned definition you are championing, information has just been transmitted faster than the speed of light (as has been done before [2], although I believe it was generally in quantum-tunneling type situations, rather than something as normal-seeming as a optical fibre.)
The significant point to take home from that part is that the "It's the group velocity that carries information" mantra is not strictly true. In this case, the leading edge of the pulse is all that is needed to reconstruct the whole thing, and then suddenly we're faced with a battle between our definition of information transportation at the group velocity (with the wave peak) and causality. Causality obviously wins, and information transportation needs a more complex definition than is covered in introductory optics courses.
Just to be a terminology stickler, you've got group and phase velocity confused.
No, it'd be you who has the two terms reversed. Group velocity is the one which defines the rate of information travel (usually), and is the one which is tricky (but not impossible) to get above c.
Phase velocity is not the 'speed of light itself', but the speed of an individual point on the wave profile, and it is trivially simple to get values greater than c - they arise naturally during X-ray propagation in metals, for example (it would even theoretically be possible using a mechanical system, if you had the time and inclination to build one).
In other words, Kaplan is estimating, from his "gut feeling," that 15% of the people who've gotten to level 60 will ALSO have spent 15+ hours a week for several months in BWL. Either the WoW playerbase (of 5-6 million) is even more fanatical than I would have guessed, or this is a big overestimate, and possibly an attempt to justify the fact that for about a year now the WoW development team has focused almost exclusively on new content for the high-end raiders who make up a small proportion of the fan base. (I guess I shouldn't be complaining, since I'm a raider myself, but hey.)
15 hours + is a pretty high estimate, I would've thought. I mean, my guild has 3 raid evenings, of which 2 were typically spent in BWL while learning it (the 3rd was a quick romp through Molten Core for easy loots and such). The comparatively casual playtime means we go a bit slower than the crazy hardcore guilds, but we have a significant portion of our founding members still not burnt out, while almost every other guild has some pretty significant levels of turnover.
That said, despite going slower, we're certainly still able to do this stuff - there are some problems if you have a bad week which prevents you from getting real experience on the new boss when you wipe on ones which should be on farm status or whatnot, but in general you can make solid experience even with a (comparatively) small time investment.
Perhaps he's a bit high on the number of people who've killed Nef now, but it wouldn't surprise me if that number was correct for the number of people working towards it.
Slashdot Mirror
Ah, you're quite right, well spotted. My break from quantum mechanics has made me sloppy.
Those probabilities should be a^2, b^2, and so forth. Seems slashdot doesn't like alt-0178.
Two points: what other states, and how do you propose we measure them? Quantum bits will typically have only the 1/on and 0/off states, by design - partly because it meshes well with our classical computing methods, and partly because most make use of concepts like spin which are naturally in up/down or the like. When isolated, they evolve into a state expressed by a|0> + b|1>, where a and b are the probability that you will observe the 0 state or the 1 state, respectively. This superposition state is impossible to observe, since the wavefunction collapses into one or the other on observation, so we can only observe either the 1 or the 0. More generally, you have a state for the entire register which is the superposition of every possible 'classical' state, with individual probabilities of being observed when you check the register of a, b, c and so forth.
Also, your post makes little since, everything is observed, which is why it exists, just because it isent observed by humans dosent mean its not observed,
This is very true, in general, and is the very reason why quantum computing is hard. The qubits have to be completely isolated from everything except the read/write mechanism, so that these particles will only be observed by humans, and nothing else, otherwise many of the requirements to make a quantum computer effective cannot be reasonably achieved.
I do believe you're mistaken. Quantum bits are exactly like regular bits in their possible observable states - that is, they are either "on" or "off" when observed. The interesting part of quantum computing comes from the fact that, when they're not being observed, they exist in a superposition of both "on" and "off" states. Now, if you put 8 of these bits together, you have a 'qbyte' which, while when it's observed it can only represent the same range as a regular byte, can be used in calculations representing every single possible permutation of the data at once - i.e. every number from 0 through 255. Each bit you add doubles the number of states you can simultaneously test using this superposition property - this is what the GP meant when he said that quantum computing scales as 2^n.
1. Why isn't [MMOG_NAME] listed?
There are four main reasons why a particular game isn't listed in the charts:
a) The game in question isn't really a MMOG, at least by my reckoning. Games like Diablo II and Phantasy Star Online fall into this category. Guild Wars developers say in their own FAQ that they do not consider their game a MMOG; in addition, it doesn't charge a monthly fee (see below). Please don't email me trying to insist otherwise; I'm not likely to be convinced.
b) The game in question is free and/or doesn't charge a regular monthly fee. Games like Furcadia, Magic: the Gathering Online, and Project Entropia are good examples; these games are normally free to play, but some players can also pay a variable amount to access additional content in the game. This makes it almost impossible to come up with a number comparable to monthly subscribers in other games.
Both points relavent in general, the most significant bit is emphasised by me.
Rather elegantly, in fact, by postulating the existance of a universe where "took off" is not a synonym for "created".
Well, yes, because that's not how science works. Theories have to be put forward which make predictions which can be meaningfully tested. If there is no way to actually test it, then it is, in effect, impossible to develop - by definition it cannot be wrong, and therefore is effectively complete, and science is 'finished', more or less. If such an idea ends up being the dominant trend, then yes, it would be something of a disaster.
I suppose we should stop looking for what started the universe, since we can't disprove the existance of God or anything. What a load of BS.
Would you class the statement "Everything happens because God says so" as scientific? I would hope not - such a statement is inherently impossible to scrutinise or critique, as "God did it" is, in this theory, a perfectly valid response. Science does not advance by pursuing ideas of that sort, but rather putting forward testable theories, and working out ways to stress them and see if their predictions hold, and refining them as a result.
That some ideas cannot be disproven is not a problem for science - instead we content ourselves with studying those that can be.
"Nearly 10 million people are online, swapping media, at any given time," he says. That May figure is up from 8.7 million people in 2005, he says.
Apparently a 15% growth rate per year is what the music industry calls 'contained'. I wish someone would come and 'contain' my savings account...
From asking various people who use it their reason for doing so, I get answers ranging from "dunno", though fake origins of the word "mouse" in computing terms as some sort of acronym, around claims that the inventor chose that name (as far as I can tell, he doesn't care), to the suggestion that "mice" could lead to confusion with the furry creature (although why exactly it does so more than "mouse" escapes me).
All in all, it seems rather pointless to me, but it's pretty much common usage in some places now, so seems pointless to complain about it.
Initially, I read that as "Sexchange.com", and had immediate misgivings about your business model.
But what if they should do X like they do it in CS/WoW/whatever other game you hate? What if it is a really valid suggestion, even for this different game? You should judge an idea based on its merits, not on it's origin.
Interestingly, they reason they're offering the government money is not as a 'kick-back', but to actually pay for the allocation, since they aren't offering any money to purchase it up-front.
"Territory" is commonly used to denote the regions of release which games are typically separated into - the big ones being Japan, the US, and the UK/Europe (sometimes the last two go together, sometimes not). I've seen it used in both English and American publications quite a bit, it's pretty much standard usage.
They beat you to it - they also did the experiment with ethylene glycol (about 15 times the viscosity of water). The same effect was observed, but only for low-order polygons. Not a huge difference in required frequencies over most depths, although the curves are rather less smooth than the ones obtained for water (presumably due to vorticies and so forth arising from the higher viscosity)
In that situation, there would be perfect axial symmetry as these wavelengths would be identical in all directions, giving a fixed circular standing wave pattern once the flow stabilised (given a symmetric bucket, obviously). However, in this case, we have a breakdown in axial symmetry, and instead have slowly rotating geometric shapes instead.
Not really, no - whirlpools and the like are a whole other kettle of fish than the result presented here. Surface deformations of rotating water and the like have been known about for a long time (and I'm sure have been postulated as an explanation in the past), this is just an interesting little anomoly which turns up under certain particular conditions. Given this is highly dependant on things like the container shape, water depth and so forth, I don't think a direct analog would be observable in the real world.
Don't you just hate redundancy in TLA Acronyms?
Do you really want to go to jail because you guessed a URL? I know I often have tried to get around sites with bad navigation by crafting the URL, I don't consider that hacking.
How often does your crafting of a URL cost a company monies on the order of maybe ten thousand dollars? (guesstimate based off how much he "withdrew" from his account after they closed it)
Very different situations - lots of things are ignored when they do no harm, but if he loses his case, he will be setting himself up nicely for Linden to smack him down a bit.
Compare it to some types of cheque fraud - the system (or teller or what have you, depending on the nature of the scam) is fooled into completing a transaction by the fraudster's manipulation of the normal procedures. Definately illegal, and very similar to this - due a flaw in the automated nature of the auction processing, he was able to complete transactions which should never have been allowed in the normal scheme of things. This wasn't a bumbling rube finding a good deal, this was someone manipulating the system with a clear intent to turn a sizable profit from it.
This basically comes down to a battle between "They should have been more careful" and the fact that he maliciously interfered with their system in an unintended way for personl gain. Given the company will probably be cheerfully loading up on words like "Fraud", "hacking", "Terms of Use" in any arguments they submit, he'll probably get steamrolled pretty quickly since courts like to pounce on words like that.
Quite understandable, but I have gotten into a bit of a habit of defending scientific arguments from people who are criticising the result based on some misremembered bit of knowledge from their past (being the token scientist in my family, it typically falls to me to explain/defend anything which has caught people's attention and which they feel is intersting/pointless), so I felt compelled to butt in here too.
It seems that the real point of this experiment is that (should they be able to produce a useful pulse with the properties they desire) it will actually be able to test the mechanism which is speculated to cause this effect, as well as simply observing the result, although that point isn't really mentioned much in the article. You're quite right that it will probably be another one of the "Established theory wins again!" situations, but hey, you gotta check to know for sure, right?
I think the real point which illustrates the issues in describing this is illustrated a few times in that quotes you posted:
the phase velocity cannot be determited experimentally and must therefore be considered to be void of any direct physical significance.
If the medium is not strongly dispersive...
These values are tools used to study a particular subset of waves - it's a very large, very useful section, but in cases where we have all sorts of quantum mechanical effects and extreme numbers coming into play, their usefulness and even their meaning is diluted somewhat, which leaves any attempt to describe them up for all these various little bits of nitpicking.
But hey, nitpicking is one of the funnest bits of science, right?
You know, I can't quite decide if this is going for humour or not - the 'Ether' which light propagated through was the major player in the theory of light for hundreds of years. However, as we learnt more about light, the requirements on the nature of the ether so that it existed, could support light waves as we observe them, and still not be picked up by all the experiments done to attempt to find it required it to have a simply ludicrous selection of physical properties, which are often self-contradictory or conflict with other ideas to the extent that it's been abandoned by all but a few obsessives.
However, there is an interesting little theory I read once - due to the uncertainty principle photons, electrons and other particles are popping in and out of existance all the time. Many real, observed forces are interpreted in these terms. The question is, do they affect regular light propagation? And if so, if you arrange a cavity (a very small one, obviously), you can restrict the particles can form inside it (as a result of the boundary conditions imposed on their wavefunction by the cavity) and hence reduce the number of particles which interact with the light, and hence get a real, measureable, and meaningful above-c speed.
Of course it's just an idea, I don't think I've ever seen it ever put forward in any serious forum, it's a very minor detail, and I must confess I've never really put more thought into it than relating the description of it than I am right now. But still, it's an amusing idea, I think.
This statement, and your criticism of the experiment, is based on out of date (or simply ill-researched) information, and it worries me that it got modded up to 5.
In this case, the group velocity is indeed faster than the speed of light - the form of the wavepacket peak (the speed of which is the definition of the group velocity [1]) travels through the fibre almost instantaneously, much faster than c. This is one of the two things about this experiment is interesting, as by the old-fashioned definition you are championing, information has just been transmitted faster than the speed of light (as has been done before [2], although I believe it was generally in quantum-tunneling type situations, rather than something as normal-seeming as a optical fibre.)
The significant point to take home from that part is that the "It's the group velocity that carries information" mantra is not strictly true. In this case, the leading edge of the pulse is all that is needed to reconstruct the whole thing, and then suddenly we're faced with a battle between our definition of information transportation at the group velocity (with the wave peak) and causality. Causality obviously wins, and information transportation needs a more complex definition than is covered in introductory optics courses.
References, cos I like that sort of thing:
[1] http://www.rp-photonics.com/group_velocity.html - definition of group velocity
[2] http://www.rp-photonics.com/superluminal_transmiss ion.html - article on superluminal transmission, including a reference to situations where the group velocity is greater than c.
No, it'd be you who has the two terms reversed. Group velocity is the one which defines the rate of information travel (usually), and is the one which is tricky (but not impossible) to get above c.
Phase velocity is not the 'speed of light itself', but the speed of an individual point on the wave profile, and it is trivially simple to get values greater than c - they arise naturally during X-ray propagation in metals, for example (it would even theoretically be possible using a mechanical system, if you had the time and inclination to build one).
See: http://www.rp-photonics.com/superluminal_transmiss ion.html
http://www.rp-photonics.com/group_velocity.html
15 hours + is a pretty high estimate, I would've thought. I mean, my guild has 3 raid evenings, of which 2 were typically spent in BWL while learning it (the 3rd was a quick romp through Molten Core for easy loots and such). The comparatively casual playtime means we go a bit slower than the crazy hardcore guilds, but we have a significant portion of our founding members still not burnt out, while almost every other guild has some pretty significant levels of turnover.
That said, despite going slower, we're certainly still able to do this stuff - there are some problems if you have a bad week which prevents you from getting real experience on the new boss when you wipe on ones which should be on farm status or whatnot, but in general you can make solid experience even with a (comparatively) small time investment.
Perhaps he's a bit high on the number of people who've killed Nef now, but it wouldn't surprise me if that number was correct for the number of people working towards it.