Guns might deter burglars, but when any irresponsible idiot can get a gun you've got a worse situation. Eg, here are two relevent headlines right from the top of today's front page on CNN, regarding idiots with guns intentionally shooting and killing people. .
FWIW, I'm not entirely anti-gun, I think there are situations and occupations they're certainly warranted. But I don't buy the whole "2nd amendment is my God-given right, guns solve everything and make the world a perfect place" argument either.
Dunno if it's fixed, there used to be a bug in slashdot that the first paragraph separator didn;'t work (not sure if it's been fixed). so i inserted a period so it didn't matter. i added a sentence and forgot to take the first dot out.
btw, there should be a paragraph separator here, between the italicized quotes and my reply, if not then the bug is still there.
Re:My idiosyncratic take
on
Divine Proportions
·
· Score: 3, Interesting
There's a term for that - intellectual masturbation.
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But the irony is that despite the author's pretence, the review is horribly written and not clear at all. I'm a physics grad student, I've read my share of poorly-written texts and articles, but in even those instancs, at least, does the author convey his message in some understandable way.
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This review was atrocious, yet the author prides himself on his ability to use a thesaurus. It seems he wants so badly to be admired as a Renaissance man, yet he only comes out looking foolish.
I'm a physics grad student, and I've had similar situations to you. Things I've learned in math classes were just abstract intangible theory, and I didn't really visualize them well enough to understand. Until I had to USE those methods in physics. Pretty much all of calculus, differential equations, linear algebra, group theory, etc.
Not to mention that the reviewer's submission is one of the worst-written pieces of trash I've ever seen. It's as if this guy thinks he's a great writer because he happens to know a few esoteric words, some foreign phrases, but his writing is absolutely atrocious. Ironic that he's criticizing another guy for a poorly-written book.
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If you want to see how a REAL scientist writes, without sound pretentious, but yet writing clearly without unnecessary obfuscation, check out anything by Richard Feynmann for instance.
OpenBSD's standard out-of-the-box install is very well-hardened security wise, AFAIK there haven't been any local or remote exploits for years. But once you start opening ports and running daemons (say even third-party daemons) then it's not necessarily secure anymore. But stupid actions by the administrator don't imply that the OS itself isn't secure.
If you want the 'real deal' for free, then you should definitely comb through the Arxiv , which are real articles written by real researchers, usually the same article that gets sent to a specific subscription-only journal later. If you want real stuff, you should have no problem weeding out any crap from real scientists. Ie, find what university or facility the scientist works in to find out if they're legit, look at references and those references, etc. There's quite alot of stuff there.
Well if you want to play that game, the Apple IIGS came out a year BEFORE your Amiga 500 and had resolution of 640x200 with 4096 colors.
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And in reality your statement (as well as mine here) are quite misleading because both systems could only simultaneously display a handful of colors (out of a palette of 4096).
But anyway, if you're going to dis Apple at least do a proper comparison.
I think you're taking those signs far too seriuosly, for the people at the conference they're just having fun. Like i said, they were poking fun at Microsoft, they weren't doing any slashdotesque "Micro$oft is for luzers" or anything.
I'm the opposite. I used to be a FOSS zealot, I've run Linux since 1998, I've gone out of my way to write reports in LaTeX instead of Word and to do presentations in OpenOffice instead of Powerpoint, etc. But now my time is worth more than a few bucks, and putzing around with my Linux box is getting too annoying.
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So last year when my GF got a Mac Mini and I started using OS X, I've come to realize that I'll gratefully pay money for Quality closed-source software. I've since even bought iWork '06, and I never would have thought I'd pay money for an Office Suite.
So what you say might be true for a select few of the harder-core FOSS zealots, but I don't see why FOSS zealots would have even been on the Mac platform anyway if they're as zealous as to switch merely for the closing of Xnu. But anyway, for the rest of the 99% of the computing populace, this OSS initiative will be welcomed.
These guys might have something to say about that, they've got a supercomputer of 1100 dual G5 Xserves running OS X 10.3.9. There are other OS X supercomputer and distributed cluster projects you can read about here.
No they're not, people here on slashdot are constantly bickering whether Apple is a hardware or a software company. It's both.
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Apple is really a solutions company. They give you the complete package to get done what you need to get done, without you worrying about the fine details. From the high end they'll sell you a server environment (Xserve + RAID + OS X Server), at the low end they'll sell you a system to let you browse the web, play with photos and make simple movies (iMac or MacBook + OS X), etc. And anywhere inbetween, they give you the tools for you to do what you want. They give you the solutions.
Sure they sell hardware, they sell software, but look where they're aiming their market, and you'll see it's really solutions they sell.
Neutrinos are notoriously difficult to detect, for precisely the same reasons that you propose using them as imaging - they can travel through nearly everything. I used to work for the SNO project back around 1996, the amount of engineering and technological sophistication that goes into a detector like this is quite amazing.
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Back in the day there were proposals about using neutrinos to communicate with submarines and other military vehicles around the planet, since neutrinos can travel through the Earth. Since a military vessel would have to have a very small neutrino detector (to keep its mobility), the detection of neutrinos by this thing would be super low. IIRC, expected usable bandwidths (not sure if they actually did the experiment or not) would be something like a byte per day, which is obviously too low to be useful for military.
I carry both a phone and a PDA, and I really hate taking both of them with me. I'd get a decent phone/PDA combo if it didn't suck. I hate trying to use the extra goodies on my mobile, so I'd rather it's interface and design be more like a PDA with a built-in phone than a phone with PDA functionality. I hope that makes some sense.
Basically, of the PDA features I really only want my address book, calendar, and phone all in one package.
I'd recommend Scottrade. I used to have E*Trade, but they're real bastards, for every 3-month period you don't buy/sell anything they charge you a $40 fee. That adds up real fast. So I just transferred my portfolio to Scottrade, where I can sit out for months on end as I'm a student and don't have much money.
I think Scottrade has commissions of $7, which E*Trade aproaches if you make enough trades (their commissions start at $15 and go down as you make more trades to $7). But as someone else said, if you've got only $1000 or so to play with, I'd suggest buying and holding some stocks for long-term investments and not really day-trading. Day-trading requires buying/selling stocks on slight upticks, for which the stock commissions (remember, you get them buying AND selling) really eat into for you to make a profit. Ie, a stock increase of a few cents would be useless to you (unless you're playing with penny-stocks which is highly inadvisable), but would be great for someone who bought a few thousand shares.
The second article said we had isolated one quantum effect in the lab, that being entanglement.
There are TONS more quantum effects than entanglement, quantum effects have been observed going back to 1900's and earlier, eg blackbody radiation, photoelectric effect, conduction of metals, semiconductors (transistors), magnetic materials, etc. Everything really is quantum mechanical, in fact the Pauli Exclusion Principle is fundamental for all of chemistry and atomic orbitals (all based on the quantum effect of an electron being spin-1/2.) Without that, all matter wouldn't exist as atoms and molecules, etc.).
Anyway, back to your first theorem, quantum entanglement has been recently measured in the laboratory. However there are two things of note. Firstly, laboratory entanglement (the entangling process and measurement) occurs at COLD temperatures (below 4.2K, probably in the millikelvins, but I'm too lazy to look it up exactly). Secondly entanglement seems to last only for short durations. If someone would be able to entangle two electrons (or other spin-1/2 particles, say some representation of qubits) at room temprature and for a relatively long time, that would be huge news. So it's questionable that the brain works like this.
Now right here I'll just briefly play devil's advocate and postulate that maybe there are some other effects in the brain that can in fact implement some sort of either entanglement, or quantum coherence instead, that work at room temperature, that might be possible, I'm not smart enough to absolutely deny that happening a priori. But given the fact that the brain works at body temperature, and thermal fluctuations at these levels tend to reduce quantum coherence (that's why cryogenics is such a big field in physics, trying to measure coherent systems requires suppression of thermal activations) it doesn't seem likely. But maybe there's some funky neural chemistry going on, akin to high-temperature superconductors (but not superconductors but some other quantum coherent system).
Any scientists worth their salt will check, recheck, recheck again, ad nauseum, their setup, their measurement errors, etc repeatedly before concluding something as groundbreaking as major changes in fundamental laws. Any scientist of reputability will nearly instantly lose their prestige by rushing to claim something as profound as new laws of physics, when in fact the effect is explained by improper calibrations or other minor yet well-understood effects. (Case in point, Pons & Fleischmann and cold fusion).
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Another example is superconductivity. When it was discovered accidentally in 1911, it required a huge amount of study and reproducing before it could be ascertained that it was indeed a novel physical effect, and not merely some side-effect (like two wires shorting together through thermal contraction). Eg, in my lab a common joke, when seeing accidentally shorting, is to claim discovery of room-temperature superconductivity.
And finally, regarding the astronomical observatories that I know if, there are TONS of papers, procedures and manuals you must painstakingly go through (there's even a friggin' dedicated help desk) to understand the calibrations, errors, etc of the sensors (eg STIS and ACS on the Hubble). So when you say error handling is sloppily done, which instruments/observatories and their associated publications are you referring to? I'm not questioning that some scientists are sloppy, but any reputable scientist (especially when claiming something profound as a rewrite of known physics) will almost certainly not be.
In other equally-important front-page slashdot news, there were these two fellars standin' on a bridge, a-goin' to the bathroom. One fellar said, "The water's cold" and the other fellar said, "The water's deep". I believe one fella runs linux. Get it?
Great-Grandparent asked the worthwhile question about the spaceship's own gravitational field affecting the experiment. The Grandparent said "Gauss's Law [wolfram.com] says that the gravitational acceleration of a body anywhere in an enclosed sphere is 0."
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First, re-read my own reply to my first comment for clarification (posted long before your comment here). Secondly, the grandparent is implying that merely having a spherically-symmetric shell implies the field inside is zero. And this is only true in the absence of any masses outside. Which in reality would include thrusters, communications, etc. I comment on all of this in my response.
So yeah, the grandparent responded to the grandparent by assuming some kind of ridiculous hypothetical experiment, while ignoring the actual reality of building a self-contained ship with sensors, telemetry, possibly thrusters, and simultaneously making this entire thing have a spherically-symmetric mass density. So in that sense I'd say my responses are well justified.
Regarding your grading methods, you seem to be one of those physics TA's that merely looks at the final answer and deducts significant points for minor arithmatic errors, despite having a 10 page solution with the correct method (eg a problem from a typical Jackson level E&M class).
The so-called 'tangents' directly follow from your original erroneous implications of Gauss's law, along with your further accusations of "confused physical reasoning" to demonstrate that you are in fact the confused party.
Do you even understand Gauss's law? My example did envelop the mass with a "Gaussian surface", the fact you don't understand that and yet resort to namecalling only makes you look both naive and immature.
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Read my first reply to my comment for more clarification if you want. But as per your comment here, the surface integral of the vector field (dot producted with its infinitesmal area element, of course) is identically zero for any surface enclosing zero net source/sink density (ie, masses or charges). Just because this surface integral (ie, a continuous sum) is zero doesn't imply the local vector field at any point on or within the surface will be zero. As perfectly exemplified by my brick example.
And finally, the gravitational field within a hollow sphere is zero only if the gravitational field is also zero in the absence of that sphere.
I wonder how they could conclude that a change of this magnitude would come from gravity leaking into other dimension and not from any of the other myriad of possible effects.
The way any scientist would. List all known possibilities of your "myriad of possible effects". Then quantitatively estimate and calculate the magnitude of those effects on the orbit's precession. If all effects are less than the gravitional effect by some quantity greater than the experiment's margin of error, then you assume you can measure this and run the experiment.
If the experiment doesn't give you the values you expect, then you find a flaw in either your theory, your experiment, or your assumptions of the possible effects, etc. If it does give you the values you expect, then you have another good data point in the MOND or similar graviational theory. In any case, you either learn something useful, and further solidify our understanding of known physics.
Just one clarification. I re-read your post and see that you mentioned "inside a sphere". That constraint can even be extended to any hollow spherically-symmetric massive object, to yield zero acceleration inside the cavity (only by virtue of the symmetry). But that's assuming that there are no other massive objects in the universe (or of significance nearby). Including any massive objects outside the sphere.
However, if there were any thrusters attached to the sphere, or asteroids or other junk outside the cavity, then these WOULD contribute to the gravitational field inside the cavity. But yes, if the engineers were somehow able to make a perfectly spherically-symmetric container that is jettisoned, and send far enough away from all other masses, then that container's gravitational field should be negligible inside its inner cavity.
And since the L4 and L5 Lagrange points are unstable points, there shouldn't be much space junk at those points. However, any craft that will stay at those points for an extended time will need to have some kind of orbit-adjustment system (eg thrusters) to keep it at the Lagrange point. I'm too lazy now to determine the time scale of how long a passive object (ie, a perfectly spherical shell without thrusters) would remain at the Lagrange point before drifting too far away to significant gravitational fields (assuming reasonable initial conditions). But presumably it would be longer than the lifetime of this experiment.
But still, the technological engineering challenges are pretty difficult. Even if the container were passive, the engineers would need to build in system sensors and telemetry into the enclosure, probably destroying the spherical symmetry, but they could account for these perturbations in the orbits, if they know the precise locations and density distributions, etc.
Slashdot Mirror
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Man shoots four and kills two after breaking up with his girlfriend
Man shoots girl for walking a few steps onto his property
FWIW, I'm not entirely anti-gun, I think there are situations and occupations they're certainly warranted. But I don't buy the whole "2nd amendment is my God-given right, guns solve everything and make the world a perfect place" argument either.
Dunno if it's fixed, there used to be a bug in slashdot that the first paragraph separator didn;'t work (not sure if it's been fixed). so i inserted a period so it didn't matter. i added a sentence and forgot to take the first dot out.
btw, there should be a paragraph separator here, between the italicized quotes and my reply, if not then the bug is still there.
.
But the irony is that despite the author's pretence, the review is horribly written and not clear at all. I'm a physics grad student, I've read my share of poorly-written texts and articles, but in even those instancs, at least, does the author convey his message in some understandable way.
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This review was atrocious, yet the author prides himself on his ability to use a thesaurus. It seems he wants so badly to be admired as a Renaissance man, yet he only comes out looking foolish.
I'm a physics grad student, and I've had similar situations to you. Things I've learned in math classes were just abstract intangible theory, and I didn't really visualize them well enough to understand. Until I had to USE those methods in physics. Pretty much all of calculus, differential equations, linear algebra, group theory, etc.
.
If you want to see how a REAL scientist writes, without sound pretentious, but yet writing clearly without unnecessary obfuscation, check out anything by Richard Feynmann for instance.
OpenBSD's standard out-of-the-box install is very well-hardened security wise, AFAIK there haven't been any local or remote exploits for years. But once you start opening ports and running daemons (say even third-party daemons) then it's not necessarily secure anymore. But stupid actions by the administrator don't imply that the OS itself isn't secure.
If you want the 'real deal' for free, then you should definitely comb through the Arxiv , which are real articles written by real researchers, usually the same article that gets sent to a specific subscription-only journal later. If you want real stuff, you should have no problem weeding out any crap from real scientists. Ie, find what university or facility the scientist works in to find out if they're legit, look at references and those references, etc. There's quite alot of stuff there.
Maybe virtual Barbarella will show up, destroy the evil Duran Duran, and help rid the world of the scourge of crappy music.
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And in reality your statement (as well as mine here) are quite misleading because both systems could only simultaneously display a handful of colors (out of a palette of 4096).
But anyway, if you're going to dis Apple at least do a proper comparison.
I think you're taking those signs far too seriuosly, for the people at the conference they're just having fun. Like i said, they were poking fun at Microsoft, they weren't doing any slashdotesque "Micro$oft is for luzers" or anything.
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So last year when my GF got a Mac Mini and I started using OS X, I've come to realize that I'll gratefully pay money for Quality closed-source software. I've since even bought iWork '06, and I never would have thought I'd pay money for an Office Suite.
So what you say might be true for a select few of the harder-core FOSS zealots, but I don't see why FOSS zealots would have even been on the Mac platform anyway if they're as zealous as to switch merely for the closing of Xnu. But anyway, for the rest of the 99% of the computing populace, this OSS initiative will be welcomed.
These guys might have something to say about that, they've got a supercomputer of 1100 dual G5 Xserves running OS X 10.3.9. There are other OS X supercomputer and distributed cluster projects you can read about here.
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Apple is really a solutions company. They give you the complete package to get done what you need to get done, without you worrying about the fine details. From the high end they'll sell you a server environment (Xserve + RAID + OS X Server), at the low end they'll sell you a system to let you browse the web, play with photos and make simple movies (iMac or MacBook + OS X), etc. And anywhere inbetween, they give you the tools for you to do what you want. They give you the solutions.
Sure they sell hardware, they sell software, but look where they're aiming their market, and you'll see it's really solutions they sell.
I like the banners they have that are poking fun at Microsoft. Such as likening Leopard to Vista 2.0 and also saying "Hasta la Vista, Vista".
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Back in the day there were proposals about using neutrinos to communicate with submarines and other military vehicles around the planet, since neutrinos can travel through the Earth. Since a military vessel would have to have a very small neutrino detector (to keep its mobility), the detection of neutrinos by this thing would be super low. IIRC, expected usable bandwidths (not sure if they actually did the experiment or not) would be something like a byte per day, which is obviously too low to be useful for military.
I carry both a phone and a PDA, and I really hate taking both of them with me. I'd get a decent phone/PDA combo if it didn't suck. I hate trying to use the extra goodies on my mobile, so I'd rather it's interface and design be more like a PDA with a built-in phone than a phone with PDA functionality. I hope that makes some sense. Basically, of the PDA features I really only want my address book, calendar, and phone all in one package.
I think Scottrade has commissions of $7, which E*Trade aproaches if you make enough trades (their commissions start at $15 and go down as you make more trades to $7). But as someone else said, if you've got only $1000 or so to play with, I'd suggest buying and holding some stocks for long-term investments and not really day-trading. Day-trading requires buying/selling stocks on slight upticks, for which the stock commissions (remember, you get them buying AND selling) really eat into for you to make a profit. Ie, a stock increase of a few cents would be useless to you (unless you're playing with penny-stocks which is highly inadvisable), but would be great for someone who bought a few thousand shares.
The second article said we had isolated one quantum effect in the lab, that being entanglement.
There are TONS more quantum effects than entanglement, quantum effects have been observed going back to 1900's and earlier, eg blackbody radiation, photoelectric effect, conduction of metals, semiconductors (transistors), magnetic materials, etc. Everything really is quantum mechanical, in fact the Pauli Exclusion Principle is fundamental for all of chemistry and atomic orbitals (all based on the quantum effect of an electron being spin-1/2.) Without that, all matter wouldn't exist as atoms and molecules, etc.).
Anyway, back to your first theorem, quantum entanglement has been recently measured in the laboratory. However there are two things of note. Firstly, laboratory entanglement (the entangling process and measurement) occurs at COLD temperatures (below 4.2K, probably in the millikelvins, but I'm too lazy to look it up exactly). Secondly entanglement seems to last only for short durations. If someone would be able to entangle two electrons (or other spin-1/2 particles, say some representation of qubits) at room temprature and for a relatively long time, that would be huge news. So it's questionable that the brain works like this.
Now right here I'll just briefly play devil's advocate and postulate that maybe there are some other effects in the brain that can in fact implement some sort of either entanglement, or quantum coherence instead, that work at room temperature, that might be possible, I'm not smart enough to absolutely deny that happening a priori. But given the fact that the brain works at body temperature, and thermal fluctuations at these levels tend to reduce quantum coherence (that's why cryogenics is such a big field in physics, trying to measure coherent systems requires suppression of thermal activations) it doesn't seem likely. But maybe there's some funky neural chemistry going on, akin to high-temperature superconductors (but not superconductors but some other quantum coherent system).
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Another example is superconductivity. When it was discovered accidentally in 1911, it required a huge amount of study and reproducing before it could be ascertained that it was indeed a novel physical effect, and not merely some side-effect (like two wires shorting together through thermal contraction). Eg, in my lab a common joke, when seeing accidentally shorting, is to claim discovery of room-temperature superconductivity.
And finally, regarding the astronomical observatories that I know if, there are TONS of papers, procedures and manuals you must painstakingly go through (there's even a friggin' dedicated help desk) to understand the calibrations, errors, etc of the sensors (eg STIS and ACS on the Hubble). So when you say error handling is sloppily done, which instruments/observatories and their associated publications are you referring to? I'm not questioning that some scientists are sloppy, but any reputable scientist (especially when claiming something profound as a rewrite of known physics) will almost certainly not be.
In other equally-important front-page slashdot news, there were these two fellars standin' on a bridge, a-goin' to the bathroom. One fellar said, "The water's cold" and the other fellar said, "The water's deep". I believe one fella runs linux. Get it?
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First, re-read my own reply to my first comment for clarification (posted long before your comment here). Secondly, the grandparent is implying that merely having a spherically-symmetric shell implies the field inside is zero. And this is only true in the absence of any masses outside. Which in reality would include thrusters, communications, etc. I comment on all of this in my response.
So yeah, the grandparent responded to the grandparent by assuming some kind of ridiculous hypothetical experiment, while ignoring the actual reality of building a self-contained ship with sensors, telemetry, possibly thrusters, and simultaneously making this entire thing have a spherically-symmetric mass density. So in that sense I'd say my responses are well justified.
Regarding your grading methods, you seem to be one of those physics TA's that merely looks at the final answer and deducts significant points for minor arithmatic errors, despite having a 10 page solution with the correct method (eg a problem from a typical Jackson level E&M class).
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The so-called 'tangents' directly follow from your original erroneous implications of Gauss's law, along with your further accusations of "confused physical reasoning" to demonstrate that you are in fact the confused party.
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Read my first reply to my comment for more clarification if you want. But as per your comment here, the surface integral of the vector field (dot producted with its infinitesmal area element, of course) is identically zero for any surface enclosing zero net source/sink density (ie, masses or charges). Just because this surface integral (ie, a continuous sum) is zero doesn't imply the local vector field at any point on or within the surface will be zero. As perfectly exemplified by my brick example.
And finally, the gravitational field within a hollow sphere is zero only if the gravitational field is also zero in the absence of that sphere.
The way any scientist would. List all known possibilities of your "myriad of possible effects". Then quantitatively estimate and calculate the magnitude of those effects on the orbit's precession. If all effects are less than the gravitional effect by some quantity greater than the experiment's margin of error, then you assume you can measure this and run the experiment.
If the experiment doesn't give you the values you expect, then you find a flaw in either your theory, your experiment, or your assumptions of the possible effects, etc. If it does give you the values you expect, then you have another good data point in the MOND or similar graviational theory. In any case, you either learn something useful, and further solidify our understanding of known physics.
However, if there were any thrusters attached to the sphere, or asteroids or other junk outside the cavity, then these WOULD contribute to the gravitational field inside the cavity. But yes, if the engineers were somehow able to make a perfectly spherically-symmetric container that is jettisoned, and send far enough away from all other masses, then that container's gravitational field should be negligible inside its inner cavity.
And since the L4 and L5 Lagrange points are unstable points, there shouldn't be much space junk at those points. However, any craft that will stay at those points for an extended time will need to have some kind of orbit-adjustment system (eg thrusters) to keep it at the Lagrange point. I'm too lazy now to determine the time scale of how long a passive object (ie, a perfectly spherical shell without thrusters) would remain at the Lagrange point before drifting too far away to significant gravitational fields (assuming reasonable initial conditions). But presumably it would be longer than the lifetime of this experiment.
But still, the technological engineering challenges are pretty difficult. Even if the container were passive, the engineers would need to build in system sensors and telemetry into the enclosure, probably destroying the spherical symmetry, but they could account for these perturbations in the orbits, if they know the precise locations and density distributions, etc.