It should go without saying that there will be creep with use of technology like this... This is such a bad idea. There are better ways to do this than biometrics, and really, does a library need to be that "secure"? What's next, are we going to require fingerprints to register at various websites? I'm sure that'll go over real well.
Not quite that big. I use one of these- typically very strong, but field falls off rapidly (1/r or 1/r^2), so shit doesn't fly into the magnet till you get within at least 2-3 meters of it (typically 1-1.5m). And you only need the big current once- the reason you use liquid nitrogen and helium is to cool your magnet to temperatures at which the material it's made of will superconduct. Put current in now, keep your magnet cool, and you no longer have to be tied into the grid- the current just keeps circling around in the material, generating the magnetic field.
As for detecting spins, there are a multitude of ways. For instance, proton spins are detected in magnetic resonance imaging (MRI) because while the spins' orientations are affected by the external magnetic field's direction, they happen to precess about that axis like a top with a certain frequency. That frequency itself can be manipulated to generate a coherent magnetic field that alternates with time, and can be detected separately from the external field by the use of a wire coil (AC magnetic field creates a voltage that can be measured). By spatially encoding via frequency and phase (i.e. x,y,z correspond to different frequencies of alternating magnetic field, or same frequencies with phase of oscillation slightly offset per position), a map of proton density can be created (more protons = more spins = more spins). In other words, an image. THe same type of coupling is utilized in other ways, such as standard nuclear magnetic resonance, and magnetic resonance force microscopy (MRFM). The latter is basically a sort of NMR atomic force microscope. Incredibly sensitive, but a somewhat complicated setup. Last summer, a research group led by Dan Rugar was able to detect a single electron spin using and MRFM setup.
A local eye doctor told me once that this is because your eyes actually tend to focus about an inch behind the glass on your CRT because of the way the image is projected. Eventually this probably causes problems.
What difference does where your eyes focus make? I can move backwards an inch while looking at any object and change where I am focusing by the same inch. That is not going to cause any problems. William Bates's ideas have been repeated quite a few times by many doctors, some of whom where little more than glorified quacks. Besides, most people are not reading their monitor at "close distances The reason people become near or farsighted is because the shape of their eyeball changes, changing the distance between the lens and the retina.
I found the IE google toolbar to be more useful than the one that comes built into Firefox. Wish they would add in all that extra functionality... I remember trying out a beta version of it for FF and coming away a little unsatisfied. However, the overall advantages of using FF vastly outweigh the few and insignificant disadvantages.
I think that two distinct definitions should be recognized here. One is the vernacular definition, the one that we use in everyday speech. For the most part, planet is taken to mean a spherical object orbiting a star with a minimum limits of mass, radius, etc, i.e. the nine planets (though Pluto really doesn't belong there) of our solar system, and like objects in other solar systems, orbiting a star.
The scientific definition, however, is a completely differe matter. I think it would be useful to classify objects methodically (I am sure this already being done). This lends itself to clear nomenclature for communication between scientists, as well as a way to incorporate new classes of objects as they may be hypothesized or observed. For instance, a clear distinction could be made between planetary (from the ancient Greek for "wandering") objects that are luminous and those that are not. It might be necessary to distinguish those that are luminous due to thermonuclear processes and those that are not. This would mean classifying stars as planets, but should there really be a distinction? Are they not all objects floating out there in space?
Any suggestions for a classification scheme, or does anyone out there know of a standard currently in use? The responses should be interesting!
Exactly. They installed a fiber-optic network sometime in the mid-90's, and have an incredible amount of bandwidth. Every room in Taft (I lived there 97-98, 2nd floor) had fiber going all the way to the rooms. Plus, all of University Circle has a wireless tie-in. But apparently, these things mean nothing to "connectivity" as Forbes and the Princeton Review see it. And that is just for one school- imagine some of the other heavy hitters that are missing from the top 25.
After having taken a quick look at the rankings, the methodology, and my alma mater's place in the mix, I have concluded that this is a big crock of shit.
Why, you ask? Well, I'm not going to say that RPI is a bad school, because it isn't, but is its IT really better than Caltech or MIT's? I have to question that, though without better data it's impossible for me to say. But I can with a fair amount of certainty that Caltech and MIT are probably superior in that respect when compared to the University of North Dakota. I mean, c'mon, who is going to believe that?
As far as the methodology goes, there was weight given to things that don't really matter- for instance, whether computers are required. A lot of schools don't require them per se, but they are a de facto necessity that no one in their right mind would matriculate without. A better indicator would have been computer purchasing programs- but that isn't what got weighted.
I also have issues with the computer to student ratio. I went to Case Western Reserve University in Cleveland, Ohio. According to this "study", there are only 3 computers for every 100 undergraduate students. What a crock! As a matter of fact, the number they list is 100 computers open for public use by students on the entire campus. I think not- I was there, and there are way more computers than that. I could not give you an exact number because I never bothered to count, but suffice to say more than 100. We are talking about a top 50 university, not Podunk U here. Also, most undergraduates have computers available to them through their department in addition to public terminals- the methodology does not consider that at all.
In the end, I find studies like this to have fairly erroneous conclusions. They never seem to agree with one another- one list may have a school like Case in the top 10, and in this one it doesn't even break the top 25. Nope, but the U. of N. Dakota is right up there! When I think of network innovation, I think of Case, Carnegie Mellon, MIT, Caltech, RPI, etc., not U. of N. Dakota. They weighted the wrong variables, and were sloppy about collecting data on those variables. In short, this study isn't worth diddly-squat, and those that read into it should be aware that the bad data and poor theory obfuscate the matter of which schools are really the most "connected".
w00t negative moderation!!! Yay! I only get negative mods from redundancy though... which is funny b/c when you are in the top 15-20 posts you really have no idea that you are posting a redundant message, since the other people posting a similar message have not done so when you originally began your post. A strange quirk of the moderation system.
Sweet, maybe I'll get off-topic on this one too.
Apparently, Louisiana is well-known for this kind of crap. In order to be a florist in Louisiana, you have to be licensed. Achieving this requires taking a $150 exam before a committee. Of course, the committee is composed of other local florists, to whom you represent competition. For a quick blurb on this, and the effort to eradicate (which has already failed), check out:
LOL, you beat me to it. And the best part is that a lot of it, if not all of it is correct. Like the opening page, that actually is a correct formula for the density of states in 3 dimensions (different in 1 and 2 D). Honestly, this is probably one of the better sites out there. I love the background for photonic crystals- it's dead on. Shout out to Kathy Kash at Case Western!
The standard physics text for intro solid state is Kittel. I would avoid this. Try Marder's text, Condensed Matter Physics. It is heady stuff, but if you want to dig deep it is a good source. An old classic for profs and grad students is Ashcroft & Mermin's text (something something solid state something).
I had a KT7A-RAID motherboard a few years back. This thing had a multitude of problems, to say the least. However, at one point it was more problematic than usual. It would keep freezing and rebooting randomly. I could barely even login in to Win2K. So finally I got fed up and opened up the case.
There, right next to the motherboard was an exposed cap. The metal sheath had shot right off, leaving the dielectric completely exposed! Unfortunately, I couldn't get the sheath back on because the dielectric was this foamy stuff that expanded outwards if it wasn't constrained by its sheath. So with a pair of needle-nosed pliers, I adjusted the sheath's bottom to accomodate the larger dielectric. Shoved it back, being careful to not break leads.
Voilá! Problem solved! This was about 2 or 3 years ago, and that system is still running strong, and without the constant reboots and freezes. The morale of the story is to not get intimidated by the multitude of electronics inside your computer's case, as you can often repair them yourself using a little ingenuity.
NASA has been bugging me for years, ever since the days of Goldin and now O'Keefe. I believe that both of these head administrators have been overly prone to political pressure, and that Goldin's search for life on Mars has directed way too much money towards the endeavour of exploring Mars specifically for life, or what we think of as life. It's a modern day El Dorado as far as I am concerned for a variety of reasons, including ambient temperature, lack of magnetic field, lack of overwhelming evidence of large amounts of liquid to facilitate mixing of various organic molecules, depressed solar intensity due to distance from the sun, etc.
And now what- we don't have the guts to fix Hubble? I think what this is really about is that we don't want to spend the money, that the head of NASA (O'Keefe is not even a scientist) is willing to bank on ground based telescopes under construction being able to fill in for what Hubble currently does (such as the almost burned observatory in Arizona). That is a dangerous, if not stupid, bet to be undertaking. Instead, we are going to throw our dollars at an improperly positioned space station that is doing trivial, not very important science and the search for life elsewhere in the solar system at a time when we are not technologically well equipped for such missions. We need to focus on near-Earth applications, going no further than the moon until we can bring down the costs and time needed to explore planets like Mars, Jupiter and Saturn for signs of life. I would rather obtain good astrophysics data than bad, inconclusive data about whether water existed in a crater on Mars many unspecified millions of years ago.
I had the same assignment as you did, or something close. EPR paradox- from the Griffith's undergrad text. And I love your prof's quote. At least people are trying to understand- unfortunately, getting your learning from TV isn't going to cut it (although I would take anything from NOVA on PBS at more or less face value, unlike Discovery or the Science Channel).
Heh, there are so many physicsists responding to this article. I love it. I don't know about you, but I can tell who has and who has not taken some formal physics and actually studied quantum mechanics, and who is trying to remember that episode of whatever on Discovery from a few months back.
Mod this up. First post I've read in answer to my parent that really captures what is going. No offense, but a lot of you are kind of talking out of your asses without having seriously studied things.
"Sam Sachdev, a graduate of the University of Iowa, is also a freelance science journalist. In addition, for between three and four hours a day, he writes fiction. Presently, he's writing a play about the relationship between gay-rights and marriage, in the U.S., and Christianity."
Here Here! Glad to see the physicists bitching about this thing. Heh, I didn't notice the photon/proton mixup, but that explains why the slashdotters keep mentioning shadow protons. Sigh. Just last week someone asked me if the world is all subjective because of physics- she was thinking of relativity. The state of science education in this country is abysmal.
Slashdot Mirror
It should go without saying that there will be creep with use of technology like this... This is such a bad idea. There are better ways to do this than biometrics, and really, does a library need to be that "secure"? What's next, are we going to require fingerprints to register at various websites? I'm sure that'll go over real well.
As for detecting spins, there are a multitude of ways. For instance, proton spins are detected in magnetic resonance imaging (MRI) because while the spins' orientations are affected by the external magnetic field's direction, they happen to precess about that axis like a top with a certain frequency. That frequency itself can be manipulated to generate a coherent magnetic field that alternates with time, and can be detected separately from the external field by the use of a wire coil (AC magnetic field creates a voltage that can be measured). By spatially encoding via frequency and phase (i.e. x,y,z correspond to different frequencies of alternating magnetic field, or same frequencies with phase of oscillation slightly offset per position), a map of proton density can be created (more protons = more spins = more spins). In other words, an image. THe same type of coupling is utilized in other ways, such as standard nuclear magnetic resonance, and magnetic resonance force microscopy (MRFM). The latter is basically a sort of NMR atomic force microscope. Incredibly sensitive, but a somewhat complicated setup. Last summer, a research group led by Dan Rugar was able to detect a single electron spin using and MRFM setup.
Seems slashdotted already, at 8 minutes past posting. Anyone manage to save a copy to bittorrent?
I found the IE google toolbar to be more useful than the one that comes built into Firefox. Wish they would add in all that extra functionality... I remember trying out a beta version of it for FF and coming away a little unsatisfied. However, the overall advantages of using FF vastly outweigh the few and insignificant disadvantages.
The scientific definition, however, is a completely differe matter. I think it would be useful to classify objects methodically (I am sure this already being done). This lends itself to clear nomenclature for communication between scientists, as well as a way to incorporate new classes of objects as they may be hypothesized or observed. For instance, a clear distinction could be made between planetary (from the ancient Greek for "wandering") objects that are luminous and those that are not. It might be necessary to distinguish those that are luminous due to thermonuclear processes and those that are not. This would mean classifying stars as planets, but should there really be a distinction? Are they not all objects floating out there in space?
Any suggestions for a classification scheme, or does anyone out there know of a standard currently in use? The responses should be interesting!
LOL. Brilliant comeback.
A estos hijueputas nunca les van a importar.
Exactly. They installed a fiber-optic network sometime in the mid-90's, and have an incredible amount of bandwidth. Every room in Taft (I lived there 97-98, 2nd floor) had fiber going all the way to the rooms. Plus, all of University Circle has a wireless tie-in. But apparently, these things mean nothing to "connectivity" as Forbes and the Princeton Review see it. And that is just for one school- imagine some of the other heavy hitters that are missing from the top 25.
Why, you ask? Well, I'm not going to say that RPI is a bad school, because it isn't, but is its IT really better than Caltech or MIT's? I have to question that, though without better data it's impossible for me to say. But I can with a fair amount of certainty that Caltech and MIT are probably superior in that respect when compared to the University of North Dakota. I mean, c'mon, who is going to believe that?
As far as the methodology goes, there was weight given to things that don't really matter- for instance, whether computers are required. A lot of schools don't require them per se, but they are a de facto necessity that no one in their right mind would matriculate without. A better indicator would have been computer purchasing programs- but that isn't what got weighted.
I also have issues with the computer to student ratio. I went to Case Western Reserve University in Cleveland, Ohio. According to this "study", there are only 3 computers for every 100 undergraduate students. What a crock! As a matter of fact, the number they list is 100 computers open for public use by students on the entire campus. I think not- I was there, and there are way more computers than that. I could not give you an exact number because I never bothered to count, but suffice to say more than 100. We are talking about a top 50 university, not Podunk U here. Also, most undergraduates have computers available to them through their department in addition to public terminals- the methodology does not consider that at all.
In the end, I find studies like this to have fairly erroneous conclusions. They never seem to agree with one another- one list may have a school like Case in the top 10, and in this one it doesn't even break the top 25. Nope, but the U. of N. Dakota is right up there! When I think of network innovation, I think of Case, Carnegie Mellon, MIT, Caltech, RPI, etc., not U. of N. Dakota. They weighted the wrong variables, and were sloppy about collecting data on those variables. In short, this study isn't worth diddly-squat, and those that read into it should be aware that the bad data and poor theory obfuscate the matter of which schools are really the most "connected".
Heh you beat me to the punch. I found it rather annoying as it prevented me from folding the magazine the way I like to, so I ripped it out.
w00t negative moderation!!! Yay! I only get negative mods from redundancy though... which is funny b/c when you are in the top 15-20 posts you really have no idea that you are posting a redundant message, since the other people posting a similar message have not done so when you originally began your post. A strange quirk of the moderation system. Sweet, maybe I'll get off-topic on this one too.
Tsk tsk for not getting your units right. One gigabyte transfer speed? What? One gigabyte per second? Per hour? Per Martian solar year?
http://www.2theadvocate.com/stories/071504/opi_edi 2001.shtml
The standard physics text for intro solid state is Kittel. I would avoid this. Try Marder's text, Condensed Matter Physics. It is heady stuff, but if you want to dig deep it is a good source. An old classic for profs and grad students is Ashcroft & Mermin's text (something something solid state something).
There, right next to the motherboard was an exposed cap. The metal sheath had shot right off, leaving the dielectric completely exposed! Unfortunately, I couldn't get the sheath back on because the dielectric was this foamy stuff that expanded outwards if it wasn't constrained by its sheath. So with a pair of needle-nosed pliers, I adjusted the sheath's bottom to accomodate the larger dielectric. Shoved it back, being careful to not break leads.
Voilá! Problem solved! This was about 2 or 3 years ago, and that system is still running strong, and without the constant reboots and freezes. The morale of the story is to not get intimidated by the multitude of electronics inside your computer's case, as you can often repair them yourself using a little ingenuity.
And now what- we don't have the guts to fix Hubble? I think what this is really about is that we don't want to spend the money, that the head of NASA (O'Keefe is not even a scientist) is willing to bank on ground based telescopes under construction being able to fill in for what Hubble currently does (such as the almost burned observatory in Arizona). That is a dangerous, if not stupid, bet to be undertaking. Instead, we are going to throw our dollars at an improperly positioned space station that is doing trivial, not very important science and the search for life elsewhere in the solar system at a time when we are not technologically well equipped for such missions. We need to focus on near-Earth applications, going no further than the moon until we can bring down the costs and time needed to explore planets like Mars, Jupiter and Saturn for signs of life. I would rather obtain good astrophysics data than bad, inconclusive data about whether water existed in a crater on Mars many unspecified millions of years ago.
Opens at $23.50, closes at $67.38.
I had the same assignment as you did, or something close. EPR paradox- from the Griffith's undergrad text. And I love your prof's quote. At least people are trying to understand- unfortunately, getting your learning from TV isn't going to cut it (although I would take anything from NOVA on PBS at more or less face value, unlike Discovery or the Science Channel).
Maybe more like Speedo in crack.
Heh, there are so many physicsists responding to this article. I love it. I don't know about you, but I can tell who has and who has not taken some formal physics and actually studied quantum mechanics, and who is trying to remember that episode of whatever on Discovery from a few months back.
Mod this up. First post I've read in answer to my parent that really captures what is going. No offense, but a lot of you are kind of talking out of your asses without having seriously studied things.
Keyword- freelance
I think by shadow particle he meant what physicists call a virtual particle. But the 'article' still sucks donkey balls.
Here Here! Glad to see the physicists bitching about this thing. Heh, I didn't notice the photon/proton mixup, but that explains why the slashdotters keep mentioning shadow protons. Sigh. Just last week someone asked me if the world is all subjective because of physics- she was thinking of relativity. The state of science education in this country is abysmal.