Try another analogy, since the one you gave is flawed (as you noticed). One which matches better is the "baking cake with raisins," in which the raisins all get farther apart as the cake raises during baking.
Of course, the flaw in this one is that the raising cake is expanding into the same 3-space you're measuring raisin separation in... while the with the expanding universe it's actually space itself which is expanding.
Analogies seem to have these problems, I guess -- which is why physicists use mathematics, not analogies, to describe the universe [unless they're this John Dobson guy;) ].
...the equations describing the "shape" of the Universe are analogous to the equations that describe flat, curved, and saddle-shaped 2D surfaces in 3D space.... The bottom line is, the Universe follows non-Euclidean geometry...
Uhhhhh... by definition, the flat universe is Euclidean -- and that's the one the referenced paper supports. From the abstract:
This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favoured by standard inflationary models.
It is exactly like that, except that you have 3 axes about which to resolve the spin of an electron. The statement that each electron is in both states is precisely why it is misleading to laymen.
I disagree -- it's simply not "exactly like that." The reason it's confusing to laymen is precisely the same reason it's confusing to physicists: QM is counter-intuitive, and not consistent with our macroscopic experience. Formally, in QM each electron is in "both states at the same time" -- the superposition of the two "observable" wavefunctions. This may be confusing, but it's what the mathematics says.
...That would be a classical but fair way to decribe the system. No QM is necessary to describe this situation. This is exactly like the envelope models.
There is no way you can use classical descriptions of the system to correctly predict the outcome of, for example, the interference slit experiment. The difference is that the "unobserved" QM system displays a different outcome (interference fringes) from the "observed" system (discrete spots), while the classical system of your cards hidden in envelopes displays the same, unchanging outcome -- whether you know the outcome or not. These two aren't symmetrical descriptions!
...Even if you could control the outcome, this would not mean that a signal can be transmitted.
I don't follow this: if you can control the outcome, you control not only the state of the local electron but also the state of the remote, entangled one. How is this not transmitting a signal? (I admit that there are tremendous problems with causality if you can do this, which is why I have problems with it -- but that's a different issue.)
Not quite right: the military does indeed use GPS for navigation. They use what's known as the Inertial Navigation System/Global Positioning System (for which I unfortunately have no link). But the same technology is used for actual flight control of at least one spacecraft.
The X-38 (NASA's technology demonstrator for the Crew Return Vehicle, AKA "Space Station Lifeboat") does indeed use INS/GPS for its primary navigation sytem. It also uses GPS for direct flight control under that huge (7500 square foot!) parafoil ("square parachute," to the skydivers in the audience). Part of the reason it can do this is that its airspeed is reasonably low under the parachute (on the order of 50 knots), and it uses a laser altimeter to determine its altitude as it closely approaches the ground.
Since the Shuttle operates under entirely different circumstances during its entire flight envelope, GPS isn't particularly workable for direct flight control -- as you noted.
The effect you describe is exactly like taking a pair of cards, one red, the other green and sealing each in an envelope while blindfolded... it is the fact that you have no control over whether you get the +1/2 or -1/2 that prevents any signal from propagating from you to him.
Ummmmm... actually, it's not "exactly" like that. Go back to the case of the interference slit experiments: what happens is that the system is in both states (a superposition of the states) until and unless an attempt is made to determine which state some component is in. At that point, each component of the system assumes a single state, all of which are consistent with each other -- regardless of their spatial separation at that time. It's as though both cards are red and green at the same time, until you look at yours -- which is not at all the same as what you've laid out, which is merely lack of knowledge about the state of your card; in fact, the state of your card is indeterminate until you open the envelope.
You can argue the meaning of "signal," but the demonstrated physical fact is that there is an apparently-instantaneous communication of some sort between the entangled wavefunctions. Your perceived inability to influence the outcome is independent of that.
What's interesting about PEAR's results, is that they seem to be saying that we indeed have an ability to influence the outcome. This is difficult for me to believe, but then most of QM is pretty difficult for me to get my mind around... given the counter-intuitive (but still consistent) results of the experimental outcomes to date, I really don't feel like saying that such-and-such is impossible.
If GodSpiral's post deserved moderation to +3, then Hartwell's deserves similar moderation -- Hartwell is indeed correct in his statements about statistical analysis.
While I'm skeptical about the PEAR results, I've got to come down on the side of accuracy here...
In optical SETI... one expects to discover intentional beacons
Hmmmm... but why do you assume that They won't decide that announcing their presence to us is sorta like driving into East LA and loudly asking, "Hey, can anyone here change a hundred?"
After all, we have broadcast our nasty habits on the evening news for quite a few decades now, so all the nearby Thems should have us figured out...
It's easy to tell that the Andromeda Galaxy is approaching the Milky Way (doppler shift alone tells us that), but Andromeda is far enough away that it could have a very large proper motion that would still be beneath the threshold of detection -- I suspect that it could easily miss us.
Is anyone aware of data which indicates that there is no significant relative motion of the Andromeda Galaxy and us, perpendicular to the line of sight? Or are Dubinski and Hernquist just assuming that the galaxies are on a collision course?
Did you see the barred spirals after the first collision? It makes me wonder if the barred spirals that we observe are formed by the collision of a galazy with a less luminous but very massive object.
AFAIK, bars (along with lots of other detail in spirals, including much of the spiral structure itself) are generally thought to be the consequence of interaction between galaxies. I don't think it would require a "less luminous... object" -- the colliding galaxies typically pass through each other, and if the approach velocities are great enough you can see the resulting disturbances long after the two have separated. (Besides, the most common place to find a galaxy is near another galaxy -- they do come in clusters, and gravitational interactions are common.
Either replace "www" with "partners" in the URL (if you can handle being mistaken for an AOL user), or log onto the NYT site with the user name and password "cypherpunk".
Then there is the news article in Science, plus the actual report itself; both of these are available to the general public, unlike much of the (subscription only) journal.
Look around you. Who buys laptops or PDAs?:Joe Sixpack with Quake in one hand and a NiMH/LiIon battery pack in the other Chris Corporate with his suit, briefcase, and hard disk full of word documents, emails, and presentations
You are omitting a large segment of the notebook-using population: engineers and scientists, who need serious computer power while on the road.
I've gone to the field for many a test and seen a veritable forest of high-power laptops in a small room in the middle of some godforsaken desert; as often as not, these notebook computers have large screens, running at very high resolutions. Myself, I need to do CAD, run various engineering and simulation software packages, and produce presentation packages and reports while using many apps simultaneously; I therefore need a large screen and a serious FPU... 1024x768 isn't really big enough, so my new notebook will run at least 1280x1024, and higher if I can manage it. I also need plenty of RAM (I'm at 140MB now, and it's marginal) and an OS that doesn't choke on a dozen open apps at once. In short, I need a desktop machine I can carry.
While I (and the other engineers I know) do use notebook computers on airplanes and in other places away from convenient power, we've found this curious little phenomenon known as extra batteries. It's a small price to pay for the ability to do in the field what I normally do in the office, on my main machine. Then again, many airliners are now equipped with power receptacles -- the ideal solution.
While I agree than many (even most) notebook users won't need extraordinary measures like water-cooled processors, there are some of us who will gladly accept whatever it takes to keep our powerful machines working. I remember my first high-end notebook, a number of years back: it cost me a cool seven large bills, and it paid for itself in less than a month. Progress for me is whatever it takes to keep that sort of trend going, and Transmeta isn't going to be part of it.
Yep, there were no end of scientists explaining why SDI couldn't possibly work... been there, heard that. Fortunately, the physical world has always been remarkably unimpressed by the beliefs about it held by even the most distinguished scientists.
What's interesting is that the scientists "refuting" SDI generally weren't involved in the military end of their field's explorations. On top of that, there were some bright engineers who, not being aware of (or impressed by) the scientific failings, went ahead and did things that "weren't possible..."
There were (and are) many components of SDI; as with any information about the military community's capabilities, the public knowledge of SDI capabilities is a mix of contradictory information -- and yes, disinformation. Some of the disinformation says that certain things are possible; some says other things are impossible.
I'm reminded of president Regan and his use of "Star Wars" technology as a negotiation tool... the president went on national television and proposed "laser beams in space" to intercept long range balistic missiles before re-entry, and deployed billions into fruitless research. Of course, at the time none of this was even in the relm of possibility... This proved to be a wonderful negotiating tool to ask the russians for concessions.
Ummmm... interesting concept, with a couple of grains of truth in it (we did in fact spend the Soviets into bankruptcy in the technology wars). But why do you think that the goals of SDI aren't achievable? Or for that matter, haven't been accomplished in part and reduced to technology (or even in limited deployment) right now?
One thing for sure, you aren't anywhere near the inside loop in the military/aerospace community. (I'd tell you more about it, but you know that old joke...)
Gee, it must be lonely, way up there on that pinacle of elitism...
Not to bang on you personally, but your post vividly brought to mind what might seem to be a totally unrelated activity: skydiving. I know a lot of skydivers, and they often look down their noses at the ground-pounders, the unenlightened who've never experienced the thrill of freefall, who've never even really though to look up and wonder what it might be like to fly their bodies in a three-dimensional world, without wings...
Of course, most people shit little brick turds at the thought of jumping out of an airplane, and simply think that the skydiver's attitude toward them is idiotic and pointlessly condescending, and that the skydiver's priorities are seriously out of whack.
Is my point clear, or do I need to get a bigger hammer?
It's not clear that they've proven that the 1GHz part supports SMP: what they did was take several of Intel's conflicting statements and specifications, select from that information the portions which were consistent with their argument that the 1GHz processor was actually identical to the 866MHz part, and overclocked the 866 and called it a 1GHz...
They may or may not have been right, but in any case they certainly did not run a pair of factory 1GHz CPUs in an SMP configuration. I'll grant that the core is almost certainly the same; but even if they are correct in their contention that the stepping is the same for the two parts, it is a trivial matter for Intel to change the packaging to render the 1GHz version incapable of supporting SMP -- don't bond the SMP pin to the die, and they've done it!
The big question from my point of view is this: why would Intel say their flagship processor won't support SMP? This isn't like the case with the Celeron, where they clearly wanted people to buy the more-expensive processor instead of the cheapie... so why don't they want people to buy their most expensive product in pairs? The Celerons were too cheap, and the early FC-PGA Coppermines (the 500E and 550E) were just too overclockable; it makes sense that Intel would want to disable SMP for them, and so they played hide-the-SMP-pin. It also appears they've gone further with the CeleronII (AKA Coppermine128), and simply not bonded the SMP pin to the die -- again, a pricing issue... But why the 1GHz part? It's hard to buy Sassen's argument that it's just heat -- that applies to single-CPU systems as well as to duals.
So I don't think the controversy is over; it has just gotten more complicated, is all.
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Re:parallel layers of gas? try concentric
on
On The Sun's Layers
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The MSNBC article is confusing, all right... but the posted article is simply confused. I've just been to the Science article, and I think I understand what they were trying to say.
They're talking about both parallel and concentric layers of gas: the concentric ones are the outer convective layer, the inner radiative layer, and the thin shear layer between them, known as the tachocline. The convective and radiative zones rotate at different speeds (not "opposite directions!"), while the tachocline changes speed periodically; the speeds of the layers above and below the tachocline also change periodically, but in opposite directions (the changes in speed are in opposite directions, meaning one speeds up while the other slows, not opposite rotations) -- which implies that the tachocline is oscillating.
While the radiative zone rotates essentially as a solid body (despite the fact that it's actually a highly-compressed plasma), the convective outer zone doesn't. In fact, the polar regions of the convective zone have a one-year oscillation coupled to the tachocline, while the equatorial regions have a 1.3-year oscillation. These, I think, are the "parallel layers" from the article.
What's entirely unexpected about this is the period: everyone thought it would be connected to the 11-year sunspot cycle, but instead there are two separate periods, 1.0 and 1.3 years, neither of which has any obvious relationship with the sunspot-cycle period. Once again, we find that the simple models aren't a great match for reality -- and science is nowhere near the end of its search for understanding of the universe. (Which is a good thing!)
Kinda hard to talk about it, since it doesn't appear to really be on the market yet. If their single-processor 1854 VIA board is any indicator, though, it should be pretty nice. The 133MHz FSB and memory access make a difference!
My major concern is that the VIA chipsets seem to leave something to be desired when it comes to memory access -- clockspeed for clockspeed, the BX boards will still whomp the VIA boards (hell, they beat the 820's with DRDRAM on some of the benchmarks!). But if you're not willing to overclock your system, the 1834 should be better than the 1832, speedwise (at 133MHz vs. 100MHz, of course). We'll see soon, I hope.
Celerons are SMP capable. I don't know if Intel has completely disabled it in the new Celerons that they just announced.
Everything I hear indicates Intel didn't bond the SMP pin to the die -- I can't find the original statement, but here's a quotation of an example. That's what I was referring to; AFAIK the Celerons up through 533MHz are fine with SMP, but the "Coppermine 128" Celerons are crippled.
Intel appears to have done something similar with the early FC-PGA Coppermines, too -- I've not heard reliable reports of anyone managing to get good SMP out of them. The SECC-2 versions are fully SMP-enabled, though.
I have heard that there are some stability problems with the Abit BP-6 that can take some effort to iron out.
I've heard the same -- people tell me they're fine for gaming, but not so good for workstation use. I have no direct experience... but I do believe that you get what you pay for.
If your software is written for SMP, or if you intend to be doing other things with the box at the same time you are running these high-end mathematical computations (especially if by "real-time" you mean that you're collecting data and analyzing it on the same machine), go with SMP. Cost-effective means Intel, since Athlon SMP motherboards aren't yet available; it also means dual, not quad, processors. Celerons are okay, but I wouldn't use them for high-end work, because of the cache limitations -- instead, go with the Coppermine PIII's, which have 256KB on-die cache, compared to the Celeron's 128KB. They will cost a bit more, but they'll be significantly faster. IMHO, the Xeon doesn't bring much more to the table -- and the cost is ridiculously higher.
OTOH, if you can't use (or don't need) SMP, go with the fastest Athlon you can get; the FPU (as others have pointed out) is much better than the present Intel PIII FPU's.
If I was building the machine right now, I'd probably go SMP: dual motherboards from ASUS and Tyan both have good reputations for stability, although they aren't the cheapest -- but uptime is more important than upfront cost, too. The BX or GX chipset solutions are much cheaper than the newer Intel 820 and 840 boards, because of the cost of Rambus memory -- and if you run SDRAM on an 820 (and probably the 840 also), you'll be slower than a BX solution anyway.
Then I'd stick a couple of reasonably-fast (600 or 700MHz) Coppermine PIII's on the board, and lots of SDRAM -- enough so the OS never has to swap to the hard drive. Only you know what that amount is, and memory is still pretty cheap.
It doesn't sound like you'll need SCSI (since drive access times and multitasking probably won't be much of an issue), so stick with EIDE for the hard drive -- the cost is much lower. Your graphics card won't be horribly expensive, either, as long as you aren't worrying about high-end screen output (if you are, it's a whole different ballgame).
A representative system (prices are midrange online values, not the cheapest by far; buying it as a package will save you quite a bit):
2 PIII 600E processors [OEM, without heatsink and fan] ($290 each)
Heatsinks and fans for those processors ($30)
IBM or Maxtor 20GB 7200RPM EIDE hard drive ($180)
256MB PC100 SDRAM ($220)
Mid-range graphics card ($100)
Generic floppy drive, case, CD-ROM and keyboard ($160)
Total price, around $1450 (without a monitor)
This is actually quite a nice machine -- good quality parts where it matters, for what I interpret your requirements as being. If you can manage with Celerons, though, get an ABIT BP-6 motherboard and a pair of the fastest Celerons which still support SMP (don't get burned, here!), and you might be under a grand, total...
Ask me again in a couple of months, of course, and everything will have changed. Remember that the newest, fastest PIII's don't support SMP (yet, anyway); neither do the new Celerons; Athlons will, next year, but they'll be replaced by other CPU's by then anyway; and YMMV.
Within 10-20 years all our communications are likely to be digital, compressed, encrypted, and spread spectrum - totally different from the trivially modulated analog stream we sent out for about 100 years. From the outside it will probably end up looking like just a few minor bumps in Earth's thermal radiation profile, certainly nothing that can be decyphered by even the most persistant extraterrestrials
Ummmmm... right now, we're beginning to be able to discover information about the very early days of the Universe by looking at "a few minor bumps in... thermal radiation profile" (of the CBR). Given that Moore's Law probably isn't just a terrestrial phenomenon, I suspect that an ET intelligent species with just a little curiosity and a couple of centuries' advance on us will be able to discover any communications we can think up -- even if they can't decrypt it, for not knowing anything about us. But it would still stand out as artificial, to someone who understood what the thermal radiation profile should look like...
That said, it's clear that we can't always find the accidental emissions from more advanced races. There's also no compelling reason that someone a lot brighter (or even just a lot more advanced) than we are, would have any reason to talk to us... I remember (from many years ago) the best explanation I've heard yet for lack of extraterrestrials' contacting us: an Aussie pilot said (about UFOs), "Sure, I fly over kangaroos all the time -- but I don't stop to talk to them!"
It's not clear why a formalized guideline is necessary: after all, most people pretty much do what they think is right, and the ones who aren't bothered by their own conscience won't pay much attention to a guideline (i.e., the conscience of others). A good example is commercial programs with GPLed code -- they do it anyway.
And most people (in a given culture) have a fairly similar notion of what's right and what isn't -- and in those areas where there's significant scatter of belief, attempts to form a consensus often succeed in merely polarizing the population (think about the ethics of abortion, or about genetically engineered foods, if you need examples). So guidelines tend to be either fairly trivial, or they amount to forcing views down the dissenters' throats...
The answer has been suggested elsewhere: the technology usually generates its own fixes for the problems it introduces. What I think we need is a free hand to operate at both ends of the spectrum -- because controls in the form of an effective (read, "enforceable") guideline will only keep the ethical from developing the fixes, while leaving the unethical free to do what they're going to do anyway.
WTF are you talking about? NASA isn't involved in the extrasolar planet detections -- it's mostly universities. They were doing it long before the last two Mars probes vanished, too.
I'm not an apologist for NASA (heh -- you ought to hear some of the stories I can tell), but you ought to realize that there's plenty of science done without them (yes, even space and planetary science), and plenty of science interest independent of NASA on the part of the media.
If you want to bash 'em, do it on reasonable grounds; don't try to link it to something else entirely...
I mis-remembered Jupiter's mass, of course -- over coffee I quickly calculated what it had to be ([radius.ratio^3]/density.ratio), then looked it up. It's about 318 terrestrial masses, which makes a lot more sense. Jupiter by far dominates the Solar system: the next closest contender is Saturn, with about 95 Earth masses, with Uranus and Neptune being puny in comparison (both well under 20 TM). Someone once said that the Solar system consists of Jupiter and some rubble...
But while I'm on the topic: the sun is something like 1050 Jovian masses, dwarfing Jupiter even more than Jupiter does Earth. This ratio is why detecting extrasolar planets smaller than Jupiter is so hard -- it's common to say that the planets orbit the sun, but actually a planet and its sun both orbit their common center of gravity. As it turns out, Jupiter orbits a bit more than 1100 times the sun's radius away from the sun's center, so the center of mass is just about at the sun's surface.
This means, to detect Jupiter at interstellar distances, we'd be looking for a Doppler shift based on a "wobble" about equal to the sun's radius (not quite 700 thousand kilometers) in half of Jupiter's orbital period (six years, since Jupiter's orbit takes 4433 days)... not much variation, over a very long time -- meaning the velocity is small, and therefore difficult to separate from measurement errors. The extrasolar planets we've been finding have mostly been larger than Jupiter, and have all orbited much closer to their stars -- barely a quarter of them have been as far out as Earth, while Jupiter is over five times that distance from Sol.
Slashdot Mirror
Of course, the flaw in this one is that the raising cake is expanding into the same 3-space you're measuring raisin separation in... while the with the expanding universe it's actually space itself which is expanding.
Analogies seem to have these problems, I guess -- which is why physicists use mathematics, not analogies, to describe the universe [unless they're this John Dobson guy ;) ].
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Especially since (by some models, anyway) it's the vacuum energy which is powering the Cosmological Constant.
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Uhhhhh... by definition, the flat universe is Euclidean -- and that's the one the referenced paper supports. From the abstract:
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I disagree -- it's simply not "exactly like that." The reason it's confusing to laymen is precisely the same reason it's confusing to physicists: QM is counter-intuitive, and not consistent with our macroscopic experience. Formally, in QM each electron is in "both states at the same time" -- the superposition of the two "observable" wavefunctions. This may be confusing, but it's what the mathematics says.
There is no way you can use classical descriptions of the system to correctly predict the outcome of, for example, the interference slit experiment. The difference is that the "unobserved" QM system displays a different outcome (interference fringes) from the "observed" system (discrete spots), while the classical system of your cards hidden in envelopes displays the same, unchanging outcome -- whether you know the outcome or not. These two aren't symmetrical descriptions!
I don't follow this: if you can control the outcome, you control not only the state of the local electron but also the state of the remote, entangled one. How is this not transmitting a signal? (I admit that there are tremendous problems with causality if you can do this, which is why I have problems with it -- but that's a different issue.)
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The X-38 (NASA's technology demonstrator for the Crew Return Vehicle, AKA "Space Station Lifeboat") does indeed use INS/GPS for its primary navigation sytem. It also uses GPS for direct flight control under that huge (7500 square foot!) parafoil ("square parachute," to the skydivers in the audience). Part of the reason it can do this is that its airspeed is reasonably low under the parachute (on the order of 50 knots), and it uses a laser altimeter to determine its altitude as it closely approaches the ground.
Since the Shuttle operates under entirely different circumstances during its entire flight envelope, GPS isn't particularly workable for direct flight control -- as you noted.
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Ummmmm... actually, it's not "exactly" like that. Go back to the case of the interference slit experiments: what happens is that the system is in both states (a superposition of the states) until and unless an attempt is made to determine which state some component is in. At that point, each component of the system assumes a single state, all of which are consistent with each other -- regardless of their spatial separation at that time. It's as though both cards are red and green at the same time, until you look at yours -- which is not at all the same as what you've laid out, which is merely lack of knowledge about the state of your card; in fact, the state of your card is indeterminate until you open the envelope.
You can argue the meaning of "signal," but the demonstrated physical fact is that there is an apparently-instantaneous communication of some sort between the entangled wavefunctions. Your perceived inability to influence the outcome is independent of that.
What's interesting about PEAR's results, is that they seem to be saying that we indeed have an ability to influence the outcome. This is difficult for me to believe, but then most of QM is pretty difficult for me to get my mind around... given the counter-intuitive (but still consistent) results of the experimental outcomes to date, I really don't feel like saying that such-and-such is impossible.
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While I'm skeptical about the PEAR results, I've got to come down on the side of accuracy here...
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Hmmmm... but why do you assume that They won't decide that announcing their presence to us is sorta like driving into East LA and loudly asking, "Hey, can anyone here change a hundred?"
After all, we have broadcast our nasty habits on the evening news for quite a few decades now, so all the nearby Thems should have us figured out...
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Is anyone aware of data which indicates that there is no significant relative motion of the Andromeda Galaxy and us, perpendicular to the line of sight? Or are Dubinski and Hernquist just assuming that the galaxies are on a collision course?
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AFAIK, bars (along with lots of other detail in spirals, including much of the spiral structure itself) are generally thought to be the consequence of interaction between galaxies. I don't think it would require a "less luminous ... object" -- the colliding galaxies typically pass through each other, and if the approach velocities are great enough you can see the resulting disturbances long after the two have separated. (Besides, the most common place to find a galaxy is near another galaxy -- they do come in clusters, and gravitational interactions are common.
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Then there is the news article in Science, plus the actual report itself; both of these are available to the general public, unlike much of the (subscription only) journal.
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You are omitting a large segment of the notebook-using population: engineers and scientists, who need serious computer power while on the road.
I've gone to the field for many a test and seen a veritable forest of high-power laptops in a small room in the middle of some godforsaken desert; as often as not, these notebook computers have large screens, running at very high resolutions. Myself, I need to do CAD, run various engineering and simulation software packages, and produce presentation packages and reports while using many apps simultaneously; I therefore need a large screen and a serious FPU... 1024x768 isn't really big enough, so my new notebook will run at least 1280x1024, and higher if I can manage it. I also need plenty of RAM (I'm at 140MB now, and it's marginal) and an OS that doesn't choke on a dozen open apps at once. In short, I need a desktop machine I can carry.
While I (and the other engineers I know) do use notebook computers on airplanes and in other places away from convenient power, we've found this curious little phenomenon known as extra batteries. It's a small price to pay for the ability to do in the field what I normally do in the office, on my main machine. Then again, many airliners are now equipped with power receptacles -- the ideal solution.
While I agree than many (even most) notebook users won't need extraordinary measures like water-cooled processors, there are some of us who will gladly accept whatever it takes to keep our powerful machines working. I remember my first high-end notebook, a number of years back: it cost me a cool seven large bills, and it paid for itself in less than a month. Progress for me is whatever it takes to keep that sort of trend going, and Transmeta isn't going to be part of it.
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What's interesting is that the scientists "refuting" SDI generally weren't involved in the military end of their field's explorations. On top of that, there were some bright engineers who, not being aware of (or impressed by) the scientific failings, went ahead and did things that "weren't possible..."
There were (and are) many components of SDI; as with any information about the military community's capabilities, the public knowledge of SDI capabilities is a mix of contradictory information -- and yes, disinformation. Some of the disinformation says that certain things are possible; some says other things are impossible.
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Ummmm... interesting concept, with a couple of grains of truth in it (we did in fact spend the Soviets into bankruptcy in the technology wars). But why do you think that the goals of SDI aren't achievable? Or for that matter, haven't been accomplished in part and reduced to technology (or even in limited deployment) right now?
One thing for sure, you aren't anywhere near the inside loop in the military/aerospace community. (I'd tell you more about it, but you know that old joke...)
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Not to bang on you personally, but your post vividly brought to mind what might seem to be a totally unrelated activity: skydiving. I know a lot of skydivers, and they often look down their noses at the ground-pounders, the unenlightened who've never experienced the thrill of freefall, who've never even really though to look up and wonder what it might be like to fly their bodies in a three-dimensional world, without wings...
Of course, most people shit little brick turds at the thought of jumping out of an airplane, and simply think that the skydiver's attitude toward them is idiotic and pointlessly condescending, and that the skydiver's priorities are seriously out of whack.
Is my point clear, or do I need to get a bigger hammer?
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They may or may not have been right, but in any case they certainly did not run a pair of factory 1GHz CPUs in an SMP configuration. I'll grant that the core is almost certainly the same; but even if they are correct in their contention that the stepping is the same for the two parts, it is a trivial matter for Intel to change the packaging to render the 1GHz version incapable of supporting SMP -- don't bond the SMP pin to the die, and they've done it!
The big question from my point of view is this: why would Intel say their flagship processor won't support SMP? This isn't like the case with the Celeron, where they clearly wanted people to buy the more-expensive processor instead of the cheapie... so why don't they want people to buy their most expensive product in pairs? The Celerons were too cheap, and the early FC-PGA Coppermines (the 500E and 550E) were just too overclockable; it makes sense that Intel would want to disable SMP for them, and so they played hide-the-SMP-pin. It also appears they've gone further with the CeleronII (AKA Coppermine128), and simply not bonded the SMP pin to the die -- again, a pricing issue... But why the 1GHz part? It's hard to buy Sassen's argument that it's just heat -- that applies to single-CPU systems as well as to duals.
So I don't think the controversy is over; it has just gotten more complicated, is all.
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They're talking about both parallel and concentric layers of gas: the concentric ones are the outer convective layer, the inner radiative layer, and the thin shear layer between them, known as the tachocline. The convective and radiative zones rotate at different speeds (not "opposite directions!"), while the tachocline changes speed periodically; the speeds of the layers above and below the tachocline also change periodically, but in opposite directions (the changes in speed are in opposite directions, meaning one speeds up while the other slows, not opposite rotations) -- which implies that the tachocline is oscillating.
While the radiative zone rotates essentially as a solid body (despite the fact that it's actually a highly-compressed plasma), the convective outer zone doesn't. In fact, the polar regions of the convective zone have a one-year oscillation coupled to the tachocline, while the equatorial regions have a 1.3-year oscillation. These, I think, are the "parallel layers" from the article.
What's entirely unexpected about this is the period: everyone thought it would be connected to the 11-year sunspot cycle, but instead there are two separate periods, 1.0 and 1.3 years, neither of which has any obvious relationship with the sunspot-cycle period. Once again, we find that the simple models aren't a great match for reality -- and science is nowhere near the end of its search for understanding of the universe. (Which is a good thing!)
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My major concern is that the VIA chipsets seem to leave something to be desired when it comes to memory access -- clockspeed for clockspeed, the BX boards will still whomp the VIA boards (hell, they beat the 820's with DRDRAM on some of the benchmarks!). But if you're not willing to overclock your system, the 1834 should be better than the 1832, speedwise (at 133MHz vs. 100MHz, of course). We'll see soon, I hope.
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Everything I hear indicates Intel didn't bond the SMP pin to the die -- I can't find the original statement, but here's a quotation of an example. That's what I was referring to; AFAIK the Celerons up through 533MHz are fine with SMP, but the "Coppermine 128" Celerons are crippled.
Intel appears to have done something similar with the early FC-PGA Coppermines, too -- I've not heard reliable reports of anyone managing to get good SMP out of them. The SECC-2 versions are fully SMP-enabled, though.
I've heard the same -- people tell me they're fine for gaming, but not so good for workstation use. I have no direct experience... but I do believe that you get what you pay for.
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OTOH, if you can't use (or don't need) SMP, go with the fastest Athlon you can get; the FPU (as others have pointed out) is much better than the present Intel PIII FPU's.
If I was building the machine right now, I'd probably go SMP: dual motherboards from ASUS and Tyan both have good reputations for stability, although they aren't the cheapest -- but uptime is more important than upfront cost, too. The BX or GX chipset solutions are much cheaper than the newer Intel 820 and 840 boards, because of the cost of Rambus memory -- and if you run SDRAM on an 820 (and probably the 840 also), you'll be slower than a BX solution anyway.
Then I'd stick a couple of reasonably-fast (600 or 700MHz) Coppermine PIII's on the board, and lots of SDRAM -- enough so the OS never has to swap to the hard drive. Only you know what that amount is, and memory is still pretty cheap.
It doesn't sound like you'll need SCSI (since drive access times and multitasking probably won't be much of an issue), so stick with EIDE for the hard drive -- the cost is much lower. Your graphics card won't be horribly expensive, either, as long as you aren't worrying about high-end screen output (if you are, it's a whole different ballgame).
A representative system (prices are midrange online values, not the cheapest by far; buying it as a package will save you quite a bit):
Tyan 1832 dual motherboard [make sure it's latest-revision, to handle Cumines] ($180)
2 PIII 600E processors [OEM, without heatsink and fan] ($290 each)
Heatsinks and fans for those processors ($30)
IBM or Maxtor 20GB 7200RPM EIDE hard drive ($180)
256MB PC100 SDRAM ($220)
Mid-range graphics card ($100)
Generic floppy drive, case, CD-ROM and keyboard ($160)
Total price, around $1450 (without a monitor)
This is actually quite a nice machine -- good quality parts where it matters, for what I interpret your requirements as being. If you can manage with Celerons, though, get an ABIT BP-6 motherboard and a pair of the fastest Celerons which still support SMP (don't get burned, here!), and you might be under a grand, total...
Ask me again in a couple of months, of course, and everything will have changed. Remember that the newest, fastest PIII's don't support SMP (yet, anyway); neither do the new Celerons; Athlons will, next year, but they'll be replaced by other CPU's by then anyway; and YMMV.
Have fun...
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Ummmmm... right now, we're beginning to be able to discover information about the very early days of the Universe by looking at "a few minor bumps in... thermal radiation profile" (of the CBR). Given that Moore's Law probably isn't just a terrestrial phenomenon, I suspect that an ET intelligent species with just a little curiosity and a couple of centuries' advance on us will be able to discover any communications we can think up -- even if they can't decrypt it, for not knowing anything about us. But it would still stand out as artificial, to someone who understood what the thermal radiation profile should look like...
That said, it's clear that we can't always find the accidental emissions from more advanced races. There's also no compelling reason that someone a lot brighter (or even just a lot more advanced) than we are, would have any reason to talk to us... I remember (from many years ago) the best explanation I've heard yet for lack of extraterrestrials' contacting us: an Aussie pilot said (about UFOs), "Sure, I fly over kangaroos all the time -- but I don't stop to talk to them!"
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And most people (in a given culture) have a fairly similar notion of what's right and what isn't -- and in those areas where there's significant scatter of belief, attempts to form a consensus often succeed in merely polarizing the population (think about the ethics of abortion, or about genetically engineered foods, if you need examples). So guidelines tend to be either fairly trivial, or they amount to forcing views down the dissenters' throats...
The answer has been suggested elsewhere: the technology usually generates its own fixes for the problems it introduces. What I think we need is a free hand to operate at both ends of the spectrum -- because controls in the form of an effective (read, "enforceable") guideline will only keep the ethical from developing the fixes, while leaving the unethical free to do what they're going to do anyway.
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I'm not an apologist for NASA (heh -- you ought to hear some of the stories I can tell), but you ought to realize that there's plenty of science done without them (yes, even space and planetary science), and plenty of science interest independent of NASA on the part of the media.
If you want to bash 'em, do it on reasonable grounds; don't try to link it to something else entirely...
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(Or is this another case of competing teams of scientists, racing to publish their results first?)
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But while I'm on the topic: the sun is something like 1050 Jovian masses, dwarfing Jupiter even more than Jupiter does Earth. This ratio is why detecting extrasolar planets smaller than Jupiter is so hard -- it's common to say that the planets orbit the sun, but actually a planet and its sun both orbit their common center of gravity. As it turns out, Jupiter orbits a bit more than 1100 times the sun's radius away from the sun's center, so the center of mass is just about at the sun's surface.
This means, to detect Jupiter at interstellar distances, we'd be looking for a Doppler shift based on a "wobble" about equal to the sun's radius (not quite 700 thousand kilometers) in half of Jupiter's orbital period (six years, since Jupiter's orbit takes 4433 days)... not much variation, over a very long time -- meaning the velocity is small, and therefore difficult to separate from measurement errors. The extrasolar planets we've been finding have mostly been larger than Jupiter, and have all orbited much closer to their stars -- barely a quarter of them have been as far out as Earth, while Jupiter is over five times that distance from Sol.
As I said, it's a difficult task.
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