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  1. Kids ask questions. on Chess for Kids? · · Score: 1
    Even if you had the world's best computer program for teaching, she will STILL ask questions. That is what kids do. It's hard-wired into their brain. Aliens come down at night and beam random question generators into kids brains.

    The first thing, then, is to learn the game yourself. Chess is not that hard - there are only a tiny handful of core strategies and tactics you really need to learn. Above all, don't bother looking ahead - that's not how the really good chess players work, they use combinations and patterns.

    Kids find patterns much easier to understand than E2-E4, so it would seem a good place to start. Adults may or may not find them easy, but it should still be MUCH easier.

    WARNING! Everything above this point is accepted theory in chess. Everything below this point is pure speculation on my part. All disclaimers apply -- unless she becomes the world's youngest Grand Master, in which case I want either 10% of the winnings or, at the very least, a bag of jelly beans.

    A good way to learn patterns is to play a game until you're about halfway through, then plug the board into a REALLY good chess program. Have it analyze the board and determine who is ahead and/or if it's even possible to win against any defence. Make a note of where the pieces are, then continue playing.

    Just keep doing this, trying to pause when you get to a similar board to one you've seen before. Compare the scores and the positions. Even if you don't know why the scores are what they are, you'll eventually develop a theory. Test that theory. Don't try to work out every possible always-good pattern, you just need two or three that are usually good and usually easy to get to.

    You don't even have to do exactly the above. The idea is solely to find a few mid-point combinations that are reliably strong and are relatively easy to reach, then to memorize those combinations.

    The second line of attack (which goes along with the first) is to learn what specific actions are generally good and which are generally bad. This isn't as reliable, there will be far more exceptions, but it can help. Some moves are going to be both good and bad. ("en passant" is a great capture move. However, it usually leads to two pawns on the same file and that is generally considered bad, as pawns are strongest when they protect each other.)

    Computers as teachers of chess are generally lousy. They typically work through a heavily pruned B+ tree, are lousy at defence and prefer specific goals to a more fluid play. It would be relatively easy to teach a computer to play "perfect" chess (you just need to solve a general 32-variable polynomial in the complex number domain) but the preferred method is to do deep-tree searches. To reduce the time cost, many of the branches in the tree are terminated early, on the assumption that those branches are not worth considering.

    If you can establish such a branch as being a precursor to a combination you know is strong for you, the computer will be incapable of detecting what you are doing and therefore will be incapable of setting up any meaningful defence.

    All that teaches you is how to attack the opponent's blind-spot. And that doesn't apply to other opponents, so is useless as a method anyway. Play as if you can win against any defence, right from the start. For one of the sides that will be true anyway*. For the other, it can be made to be true, so long as you don't let yourself get thrown by their playing. For one side, even if the other side plays perfectly, a win is guaranteed so long as you don't do anything actually harmful to your position. For the other, all they have to do is make one mistake less, when self-harm is done.

    *This was proven to be true of any "full information game" by Von Neumann. Well, almost. The actual proof is that all "full information games" that are played perfectly guarantee a win or draw. Nobody, yet, has established if Chess bel

  2. You're neglecting one important fact... on Windows Vista x64 To Require Signed Drivers · · Score: 5, Insightful
    Since only commercial vendors can be licensed, any garage developer (Messers Hewlett and Packard, for example) can build their own hardware but NOT be licensed to produce a driver for it. Only a pre-existing commercial vendor can do that, and most won't unless you pay them.


    This not only means that you can't have third-party drivers, it ALSO means you can't have 1st party drivers from start-ups. It effectively prohibits anyone new from entering the hardware arena.


    But there's more! Although Microsoft's license is "free", they aren't necessarily going to give a license to everyone. Thus, they can effectively ban technology they don't like. Blu-Ray vs. HD-DVD is going to be the shortest battle on record, if all it will take is for Microsoft to prohibit rival systems running on "their" desktops.


    There is a way round the problem, but it puts you at risk from the DMCA as (by definition) it is circumventing security technology. By having a hypervisor-like OS running at the lowest level, and then having Vista run on top of that, you can make any piece of physical hardware look like any other piece of hardware that you like. Nothing Vista can do about it, as it can't see the hardware directly, all it can see is the results of pushing data of one type in one direction, then pulling data of another type in the opposite direction.

  3. Some thoughts on Slashdot Index Code Update · · Score: 2
    First, you really, truly, do NOT want to bubble-sort the main page. Especially with dynamically-sized bubbles. That would not be pretty. However, the idea does sound excellent and I think it could be made to work.


    My first thought would be to have a "virtual" section for the most popular stories. All that section would do is beg/borrow/steal articles from other sections and reformat them to the way desired and in the order desired. That takes care of avoiding the dupe-detector but at the same time retaining stories of exceptional significance.


    My second thought is on the code for varying the size of the intro. I've a feeling that that code could get a little messy - but maybe you don't actually have to vary the number of lines... *Evil cackle* For most graphical browsers, you can alter the size of the font, instead. Hey, users who want to read the whole intro can just fire up the magnifying-glass tool. The advantage of the font method is that then you're just setting a variable, rather than parsing a string.


    My third thought would go great on its own or in parallel with the above. And that is to allow users, in their preferences, to define a search criteria. (A regular expression and a section, perhaps.) Anything that meets the criteria is set "sticky" and will "stick" on that user's front page for an extra while (say until read, unstuck or the glue wears off).


    *Whichever suggestions above sound interesting are mine. The rest were invented by alien space monkeys that were holding my brain hostage.

  4. Dominant but not innovative on Apple Nearly Moved to SPARC · · Score: 1
    Apple has always gone with trying to be the most creative. The Apple Newton was a good example. Great idea, creative for the era. In many ways, it wasn't Apple's fault that the technology of the time simply wasn't up to what they wanted with the Newton. The same is true for the original Macs and why they were not simply an evolution of their very popular Apple II line.


    So, if innovative and creative are the name of the game, I'm actually surprised the Sparc was considered at all. The MIPS would have been a better choice, from that perspective as well as in terms of novel design. Not sure if the Transputer was still in circulation at that time or not, but that really SHOULD have appealed to Apple - parallel processing was starting to get people's attention and the Transputer was the best design out there. Arguably, in some ways, it still is - it is horribly difficult to get SMP to scale beyond 32 processors on a single node, but a High School student could build a 1024 processor Transputer block.


    What other processors really stand out...? There were some interesting efforts to build processor-in-memory systems at that time - again, it would have been highly novel (which Apple liked) and would also have been fast (no delays in fetching from main memory). High-level processors (that could run 3rd generation or even 4th generation languages as the instruction set) would win on novelty, but never got anywhere, so would probably have fallen under Apple's radar entirely.


    Asynchronous processors were also beginning to take off. Great for novelty, would have been superb from an IP standpoint (the rest of the industry wouldn't know HOW to clone them, even if they wanted to) but again really didn't make as much of a splash as a lot of people thought.


    A better bet for Apple, actually, might have been to buy out a small-scale CPU manufacturer like Inmos and build a CPU that perfectly met their requirements. It would not have cost substantially more than buying the PPC from IBM, it would have given them "editorial control" over the instruction set, and they could have recouped the investment by selling the processor as well as the computer.


    To me, that would have been one hell of a "what might have been" - a cross between Transmeta (ten years early) and SGI (who were doing very nicely at the time).

  5. Nonono. They need to ask the BBC! on Spacecraft, Heal Thyself · · Score: 1

    If auto-repair circuits were possible in Blake's 7, with their budget, it should be trivial for modern engineers.

  6. Re:Depends on who you listen to. on Cringely on Domestic Eavesdropping · · Score: 1

    Will you settle for continuous with discontinuities and maybe an imaginary component?

  7. Depends on who you listen to. on Cringely on Domestic Eavesdropping · · Score: 4, Interesting
    There are plenty of people who argue that Churchill (at least) and possibly FDR knew perfectly well about the impending attack and did nothing, in order to draw America into the war. If you believe this theory, then this is a great method to manipulate others by selectively handing out information for political gain.


    There are plenty who argue that neither knew about the attack, which would mean that those planning such things are probably smart enough to be discrete about it, which would mean that such surveillance is utterly worthless.


    There are claims that Churchill knew about the attack, because older Japanese diplomatic codes had already been broken and enough could be extracted from messages to know the generalities even if not the specifics. (The newer diplomatic codes used were apparently derived from the ones that had been broken, to the point where partial decryption was possible.) If that is the case, then basic signals intelligence between key figures would seem to be more valuable than general monitoring.


    Regardless of which of the popular theories you subscribe to, there is one common aspect - the kind of spying being practiced against American citizens is useless, whether or not other forms of signal intelligence has any value.


    (Actually, existing sigint practices in general seem pretty crappy. We've had numerous false alarms, where the threat level has been raised but no evidence of any attack ha ever emerged. On the other hand, actual attacks in very recent times - such as those in London - were missed entirely.)


    It does nothing to raise confidence levels when you realize that several top US Government officials have been arrested on spying charges in the US... ENTIRELY through a mix of blind luck, observation and routine detective footwork. If the US monitoring program can't even monitor national secrets and foreign agents, then it's not much use as a monitoring service.


    Well, either that or it's not being used to monitor "threats" of that kind at all, which raises the question of what it IS monitoring. Nixon's crusade against the Democrats had far more to do with keeping himself in absolute power than with keeping the country safe, and Hoover was notorious for finding out the dirty secrets of anyone who could threaten his personal powerbase. Not to be cynical (reader: "you expect me to believe that?") but a comparison of results versus approach would seem to indicate that this program isn't as much for the benefit of national security as we're being told.

  8. Re:Earth, air, fire, and water on The Semantics Differentiation of Minds and Machines · · Score: 1
    We've progressed to the realization that all matter is liquid, gas, solid, or plasma.


    Heh! That works so well, it would be a shame to add in the other 13 or so states of matter. :) The quantum version (quark, lepton, gluon, baryon) neither rolls off the tounge so well nor matches up with the primitive categories. Yours does superbly, if arraged "solid (earth), gas (air), liquid (water), plasma (fire)", demonstrating that an Age of Reason and 2,000 years of progress really isn't worth a whole lot.

  9. Take that one step further. on The Semantics Differentiation of Minds and Machines · · Score: 1
    I think you're on exactly the right lines, there, but would extend the argument a little. I believe that the components of something (whether of a biological entity or a silicon entity) can - and do - process data on a structural level. So, when you are looking at a machine as a set of components, you see those components processing how something is organized, in other words the syntax of the data.


    I believe that complete entities are geared much more towards the manipulation of concepts as the fundamental unit. This is where the semantics live - not in the nitty-gritty details of the specifics, but in the vast artistic expression held by the whole.


    If you were to take a neuron from a human brain, you would find no evidence of any semantic processing (I believe, anyway) but that doesn't mean the brain - when taken as a whole - is incapable of such processing. It all depends on the level you're looking.


    Different scales have different meanings. Sentience will never be observed in a single human brain cell, although it's usually seen when you look at the brain as a whole. For the same reason, how can anyone expect to see sentience in a single transistor or single clock chip? We wouldn't ask a molecule of seratonin to write the works of Shakespere, so why expect it of a PCI bus?


    I may be wrong about the timescale, but I am firmly convinced that I'm correct on the basic principle - the observation of sentient machines of any kind will only be possible once you look at the "sentience" and not at the "machine". As long as we remain focused on the microscopic and ignore the macroscopic, it is entirely possible someone will invent AI and not even realize it.


    It is possible - but very unlikely - this has already happened. The brains of crows and African Grey parrots exhibit a high level of intellectual capacity. If you ignore the parts that deal purely with the complex mechanics the birds have to deal with but the computers don't, it is possible modern supercomputers can demonstrate intelligence of equal magnitude.

  10. One of many examples. on The Semantics Differentiation of Minds and Machines · · Score: 4, Informative
    Humans are excellent at differentiating between things that are really the same, or inventing totally new layers of reality because of flawed assumptions about the way the world works. Today, I think we've gone beyond needing to think of fire, earth, air and water as being the four elements from which all physical matter is constructed, and light does not need an aether to "travel through".


    For that reason, any attempt to differentiate the mind and computers by using comparisons that aren't really meaningful or applicable should be thrown out. Maybe computer-based intelligence will never exist, but if that is the case, it won't be for the reasons we're being given.


    For example, looking at the high-level functionality of the brain and comparing it with the transistors of a computer is an absolute give-away that the author isn't going to let the facts get in the way of a good story. The low-level mechanics of the brain (the chemical and electrical signalling) can be reasonably compared to the low-level mechanics of a computer, because it is valid to compare like with like. For the same reason, it would be fair to compare the Operating System of a computer to the ancient "reptilian" core of the brain. Both are designed for housekeeping operations and are used by the higher levels to mask implementation details. And so on up through the layers.


    It should also be kept in mind that the human brain is capable of almost ten times the throughput of a top-of-the-line supercomputer. Given that one of the limiting factors of parallel architectures is the interconnect, it does prove that our networking technology is still extremely primitive. This is important, because it is going to be hard to build a machine that can "think" like a human if we have the "neural" interconnects of a Diplodocus.


    At the current rate of technological progress, I do not believe we will have a computer powerful enough to model the human brain until 2015 or 2020. Even then, it'll be a Government-owned supercomputer likely used for weapon simulation. We won't see Strong AI researchers get hold of such machines until maybe 2060 and (if the usual development patterns hold) nobody will have any idea how to turn the raw computing power into something useful until 2100 at the earliest.


    So, really, the earliest we could possibly really know (for certain) that the mind is (or isn't) like a machine is 2100. Anything stated with certainty before then is pure ego-stroking for the group of supporters attached with one camp or the other. Doubly so when it is provably and obviously intended to be deceptive.


    The only problem I see with debating the matter from an intellectually honest standpoint until then is that current global warming models put most of the planet under water or under rainforest by 2100, which means that we might never really know the results of the research anyway.

  11. So what you're saying is... on Pluto Probe Launches · · Score: 1

    ...if they'd thought ahead a bit, added a robot arm and some extra fuel, New Horizons could have caught up with one of the older probes and refuelled it. Maybe re-align or repair the main antenna, change the oil, replace the gold disk with a DVD that has the director's cut and some bonus tracks...

  12. Nah. Stopping would have been easy at any speed. on Pluto Probe Launches · · Score: 3, Funny

    Now, being able to walk around afterwards kind-of puts a limit on things, as did the "returning safely", but just the stopping would have been a piece of cake.

  13. Anyone have a pic link for the most important one? on The Backhoe, The Internet's Natural Enemy · · Score: 1
    The JCB GT is the world's fastest excavator, with a top speed of 110 mph, but (as in the link I just gave) most references are not much more than one or two lines. (The longest article I've ever seen was a single column in a Brands Hatch booklet for - I think - the 1995 Grand Prix.)


    Recognising one of those - ESPECIALLY if it's digging up cables - would be very important. Can you imagine how many cables it could go through in an hour?

  14. Hello 2003. on Boosting Socket Performance on Linux · · Score: 4, Interesting
    The paper is 2 years, 2 months old. Many of the arguments will still be valid, but the code in all cases will have evolved considerably. In addition, other code has certainly been developed (there's a hard real-time UDP patch for Linux, for example) and the state of affairs is - if anything - much more muddled today.


    Documentation like this is great and extremely valuable. It would be much more valuable, however, if it remained current. For example, can the ABISS project (which improves block I/O) be used at all? What do the numbers look like, when using profiling tools like Web100 (which profiles TCP communications)?


    Has anyone run the Linux or one of the *BSD kernels through DAKOTA, KOJAK or PAPI to determine where, precisely, bottlenecks are within the kernels? It's easy to theorise, but isn't it cleaner to measure?


    Now, I'm not saying these things aren't being done. They probably are, somewhere, by someone, but if the results aren't getting published we don't really know what impact what changes are going to have. The current method of evolving Operating System code in general is often a mix of personal theory and subjective experience based on non-random samples of activity. That can't really be a good way to do things, can it?


    If I'm wrong, feel free to say. If I'm right, then maybe it would be a good thing if someone (possibly me) put together some kind of testing kit for measuring Linux kernel performance and actually measured the stats for Linux kernels on some kind of regular basis.

  15. Probably varies. on 27 Unknown Species Discovered · · Score: 5, Informative
    In New Zealand, you'll find caves filled with glow-worms, which feed on insects that fly in. In many caves with lake systems, you'll find sightless fish that feed off algae that comes in from the outside. Caves with geothermal heating may well have extremophile algae that live off the chemical soup. In general, life tends to be extremely creative in its methods of surviving and adapting.


    (Ice worms, another recently discovered species, can only survive in freezing or near-freezing conditions and live in glaciers. They crawl to the surface at night and feed off any organic matter that has settled on the ice. They were discovered in Washington State, I believe.)


    What shocks me is that many of the species that have been discovered in the past ten to fifteen years (the Wollemi Pine, for example, as well as the Ice Worms) have largely been in very well-explored, well-documented regions that may not be exactly on the beaten track, but have certainly been visited by knowledgable experts many times over many decades. In some cases, many centuries.


    Some of these discoveries (as in this case) have been through inadequate study. Other cases have been uncovered as a result of genetic studies proving physically similar organisms to actually be unrelated. (The converse has also happened.) Yet others have been through skeptisism obstructing observation. These things are all understandable and are inevitable. It's shocking only because virtually all environmental and developmental policy is based on what is known, and what is known is proving to be limited.


    We'll be discovering new species for a long time to come, but if we had more scientists doing basic field-work and/or DNA mapping, we'd find them a lot faster. The problem is, basic research isn't profitable (so corporations are generally uninterested) and isn't vote-winning (so politicians don't care). The sciences don't come cheap, but if nobody is going to cough up the cash, it will be left to pure chance on the encounter and blind luck on the necessary awareness. To me, that feels utterly wrong. Knowledge should be gained, not gambled.

  16. Needs to be tested. on Penguin Not Taking Flight Down Under · · Score: 4, Insightful
    I'm not convinced. We've seen similar remarks from the Gartner Group for the US, despite all evidence to the contrary. Furthermore, it is still common enough practice in large companies for admins to install something stable (like Linux, a *BSD, or whatever) in place of a Windows server, but not to tell their bosses. So long as nothing goes wrong, everyone's happy - the system will crash less often and handle more users, so CEOs and the like are not going to make any enquiries as to what is being used.

    For all we know, 100% of all companies in Australia and New Zealand are using Linux and/or a *BSD for their web server, mail server, ftp server, print server(s), DNS/DHCP server, etc. The only ones of those you can test are the ones with a public interface, and I'll bet you anything you like that these market researchers don't have a copy of nmap handy, even to test those.

    It is very hard to determine actual uptake of Linux, until it reaches a critical threshold of acceptability in a region, because it is so easy for it to stay under the radar.

    For smaller companies, the bosses may well know about Linux installs but not want to admit to them, fearing looking bad or being perceived as cheap. Again, that's not going to change until Linux is deened acceptable enough. No sane boss is ever going to say something that puts their end-of-year bonus at risk.

    Finally, on the results aspect, it also depends on how the question was asked. It is easy for studies to ask questions in a way that forces the response. If you answer a particular way three times in a row, you're likely to answer the same way on the fourth question without thinking about it. Studies are extremely difficult to do well. This is especially significant when someone with a vested interest in a result pays for the study, as it is (by the nature of the beast) extremely easy to ensure the results match what the sponsor wants to see.

    (I don't believe a single study on the dangers of smoking, sponsored by a tobacco company, ever established even the remotest possibility of there being a connection between product and result. I've even seen surveys showing sugar isn't a factor in tooth decay... sponsored by sugar companies.)

    The bit about trojan horses is indicative that there's something more to this than meets the eye. The implication is that people have been "gifting" companies with Open Source, only to slam them with high service charges, perhaps for maintenance or administration. (eg: a company might provide Linux servers and not pass on the license fee, but charge double for all technical support calls.) Either that OR the reader is supposed to believe that is the case.

    The "trojan horse" is really just a play on Microsoft's "Total Cost of Ownership" attack on Linux, where Redmond accused the Penguin of being more expensive when all costs were factored in over time. I can't see Microsoft themselves going after a market that they'd barely notice even if it did switch overnight, but I'd be willing to bet that those sponsoring and/or running this study have read Microsoft's claims and phrased questions accordingly.

    Sadly, I know of no country where manipulating market research constitutes conspiring to defraud. If anything, most countries seem to encourage deceptive use of market research to the point where it is simply not possible to trust any results that are produced, even though it is hazardous (in that you're not listening to the user's requirements) to not have such information. However, because it is statistical, such studies can always produce results anywhere in the distribution function, including the extreme tail end. The sample size is generally very small and the confidence limits are usually not stated, so there is nothing anyone can do to really fight the claims. All that can be done is to find a group with greater influence and get them to falsify - err, produce - a counter-claim.

    Either that, or conduct a real, in-depth, self-vali

  17. The only good bug... on BBC Writer Responds To Mac Security Critiques · · Score: 4, Interesting
    ...is a squished bug. (See xroach for details.)


    Seriously, the argument that there are exploits is an important one to keep in mind. Nobody questions that Firefox is so far ahead of IE on security that the difference can be measured in red-shift. However, anybody who then concludes that Firefox users can afford to be complacent is completely outside the Universe entirely. The same is true of OS vulnerabilities. If a vulnerability is detected, it needs fixing. Ideally, you write the software correctly in the first place so that there are extremely few vulnerabilities that ever need to be fixed, but that doesn't generally happen.


    Is Bill Thompson a troll? To a degree. He has absolutely zero diplomatic touch, which is presumably why the BBC put him on the technology desk and not in foreign affairs. If you're in a war-zone, tact is an important skill to have.


    The part that concerns me most, which I'm not seeing enough commentary on, is the extremely serious allegation that Apple have deliberately installed backdoors into their systems. If this allegation has any foundation in fact, Apple should face intense questioning on their conduct. Cisco got burned when the backdoors they installed were discovered and although you can argue that an Apple is not quite as critical a part of the infrastructure, backdoors are certainly not ethical and possibly not legal.


    I've heard people arguing that you can't prove a program bug-free (actually, the Halting Problem only proves you can't do so for the general case, it says nothing about specific cases), but the more I hear of people abusing trust (eg: Sony), wilfully releasing defective software with known and documented bugs on the grounds people will update eventually anyway (Microsoft) and incorporating deliberate backdoors (Cisco), the more I am convinced that there should be consumer protection legislation that forces software companies to maintain certain standards. These sorts of wilfull, knowledgable, abuse of consumers is simply not acceptable.


    And, yes, I don't care if it takes a BBC hack journalist to point this out.

  18. But... on Who Owns Baseball Statistics? · · Score: 1
    Would they have to buy the rights to the poll in order to do so? But, then, if one of the Baseball celebrities voted in the poll, and they own the rights to all statistics involving Baseball celebrities, wouldn't that mean they own the poll already? And, if so, did they give the pollsters permission to release the results?


    It is in questions like this that we find insanity^H^H^H^H^H^H^H^Hcthulhu^H^H^H^H^H^H^Hthe crux of the matter.

  19. That's nothing! on Who Owns Baseball Statistics? · · Score: 4, Funny

    I bought Avagadro's Constant and the Hubble Constant off eBay, and I own stock in e, pi and the golden ratio.

  20. Empty Space on Galaxies Floating on a Dark Matter Stream · · Score: 2, Interesting
    There is no such thing as empty space, as that would violate all kinds of laws of physics. (It would exist in a constant state of entropy, there would be zero quantum uncertainty, it would allow for the possibility of an absolute frame of reference, etc.)


    In general, the popular belief is that ALL of space is filled with "quantum foam", which contains a mass of virtual particles whose sum (over any statistically significant volume) will be zero. These virtual particles are not "dark matter", precisely for that reason - dark matter (if it exists) sums to extremely large values.


    These virtual particles are of all sorts and would include quantum wormholes and quantum black holes amongst others. Now, although on average quantum foam has absolutely zero impact, it can have very local, short-lived effects. Hawking radiation would be one. It may be possible these local variations can account for everything "dark matter" has been attributed to.


    "Empty space" contains (according to theorists) all sorts of other exotic phenomena. "Superstrings", for example, which have negative gravity and essentially fill all of the other functions attributed to "dark matter" PLUS being one step closer to unifying gravity with all of the other forces, at the cost of having to live in a twelve-dimensional universe (or is it 15, now? Superstring theorists keep adding more.)


    Again, though, superstrings would eliminate the need for "dark matter" and would even be a "better" explanation for the odd layout of those galaxies. The antigravitational effect of superstrings would rip apart galaxies that weren't threaded, so threading is exactly what you'd expect. (I wonder if they're POSIX threads?)


    These all assume, of course, that anything new is required at all. Current theories that require something to be present may simply be consequences of being based on observation, as observation requires something to be present to be observed. You cannot observe nothing, because you can never prove that it truly is nothing, only that it lacks all the somethings that you would normally observe.


    The gravitational models of the galaxy that required "dark matter":


    • were based on Newtonian physics and took no account of relativistic effects on space, time, mass or distance. Nor did it take account of the finite speed of gravity. It also missed out on all quantum cosmology, though I couldn't name how that would impact things.
    • lacked a lot of the information that has recently been discovered (such as the warped shape of some of the structure) which would mean that gravitational sources would be incorrectly placed
    • have assumed the Milky Way to be stable, whereas it has collided with galaxies many times (and will do so again within the lifetime of our sun), which means that estimates of momentum in the early galaxy will be waaay off


    Now, it can be argued that that was not the only model that required "dark matter", but I will argue that if we keep the dark matter in, we now introduce errors by having variables that try to compensate for something that doesn't happen. I will also argue that cosmologists should verify that ALL of the factors I've listed have in fact been taken into account with all these other "dark matter" scenarios.


    This is not to say I'm convinced by the other theories, either. I don't like adding large numbers of variables purely to eliminate other variables. That's messy and a sign of really bad science. The quantum foam, for my money, seems to be the "best" of a bunch of really screwball ideas, and is probably sufficient to account for all of the effects that everything else is intended to describe.

  21. Tandem accelerators on New Ion Engine Being Tested · · Score: 2, Interesting
    The technique is used in tandem accelerators. You have a grid that is negatively charged (so it attracts the ions) immediately prior to the grid that is positively charged (that repels the ions, once they are through the negatively-charged grid).


    Whether this is efficient to do depends on the speed of the ions. As the velocity of the ions increases, the mass increases and therefore the energy required to achieve the same level of acceleration also increases. Of course, the grids have mass, as does the energy source, so you increase the amount of force needed to achieve the same acceleration.


    The ESA are a lot of things - many of them unprintable - but I am prepared to believe they're smart enough to have done studies on multi-stage accelerators as most European physicists have worked on them. (Many particle accelerators in Europe were of this kind, at one point.) If they're only using one grid for acceleration, there's a good chance they'll have crunched the numbers and decided that a single grid was the best bet.


    Unfortunately, politics in European space research is (almost) as bad as in NASA, so it cannot be automatically assumed that the solution adopted actually is the option the engineers and ion engine scientists would have preferred. For that reason, I would certainly encourage anyone who knows the science to offer up guesstimates on what different configurations would be like. I would ALSO encourage CmdrTaco and the Slashdot team to see if they can pester someone at the ESA into giving an interview.

  22. Other than for literary considerations... on Norway to Build Doomsday Seed Bank · · Score: 1

    I don't know why. A Lancaster bomber and a Grand Slam would be sufficient. (Yeesh, those things could punch through a 20' reinforced concrete wall! They would use this combo, in WW2, to literally chop up U-Boat pens.)

  23. Re:Yeah but will we be able to use our cell phones on FCC to Auction Airwaves for Inflight Internet · · Score: -1, Troll

    By the time you can, there won't be any gas. Either because it has run out or because the US Govt. has decided it could be used by terrorists to drive places. Or set fire to things, but I can't see why that would worry them.

  24. Easy one to test. on WMF Vulnerability is an Intentional Backdoor? · · Score: 2, Insightful
    There are many ways in which 1 could purely coincidentally be tested for - using multiple bitwise operations that don't completely cover the word, for example.


    However, there are a few very specific ways in which you would write code to deliberately look for that specific value in a specific portion of an operation. These ways can be checked by inspecting a disassembled version of the code. (But do this outside of the US, or the DMCA droids will Use The Force.)


    Since WINE shows the same hole and the coders are not the same, it would be my guess that the problem is specifically in a DLL that is used/usable by both. It should also be possible to massage WINE to fire up a disassembler with the correct entry point into the DLL that has the hole, when passing the exploit payload. It might take a while (I suggest getting a few month's supplies in advance), but it should be possible to determine exactly where the exploit is, whether it looks "natural" or not*, and whether that specific section of code is likely called by other graphics routines.


    *A "natural" bug could include a series of conditionals and jumps, where the 1 is simply the untested case that falls into random code. An "unnatural" case would be to test specifically for 1 and to jump in a different way than for other cases. (eg: If other cases jump to subroutine, and 1 does a one-way jump OR on return is the sole case that jumps over all error conditions.) If that one case has an abnormal test and an abnormal jump, it would be next to impossible for it to be accidental.


    Actually, it might be useful against Microsoft in their appeal over the EU ruling. The EU ruling demands greater transparency of protocols and code, and demands code be uninstallable by someone. The politicians might not care much about the exploit, even if it were deliberate, but I'd be willing to bet the EU's lawyers would. Even if Microsoft as a corporation were innocent (yeah, right), it demonstrates a valid legal concern that cannot be resolved using totally closed, airtight methods.

  25. I expected that. on Linux Desktops Send NASA Rovers to Mars · · Score: 5, Informative
    I worked at NASA Langley in the late 1990s, and there was a move towards the desktop and away from X terminals. However, the desktops they gave everyone were Windows based and did not have Cygwin installed, making them damn-near useless as all the applications were X.


    As I recall, I was one of the first there to really kick up a fuss about Linux, and since that time I'm very glad to say that most of the computational fluid dynamics code (ie: the stuff they use to simulate aircraft and jet engines) almost universally supports Linux. Not quite - the stuff for migrating CAD to grids and back isn't Linuxified - but everything else seems to be.


    One of my really fun tasks, whilst there, was to migrate FROM Visual Basic to X/Motif. Yeah, sure, Motif wouldn't have been my first choice either, but I got the interface to work many times better under that than it did under VB.


    About the only thing I really hated about Nasa Langley was their insistance on using rsh for all network connections (even over the Internet) and their use of .rhosts files on all internal machines. It was a major hole and I can remember expressing my displeasure to the chief of network security at Langley. Strangely, I was sacked shortly thereafter. Since then, I've learned rather more tact, but I guess my core complaint hasn't changed a lot. It's all fine and good, talking about "bugs in the Linux kernel", "FIPS-180", etc, if it gets the organization to do better than they would otherwise. When it is used to cover their ass because they know what they have is crap but they don't want to risk change, then I regard their excuses as little more than the Peter Principle in action.


    It sounds, from what I'm seeing today and what the article and others are saying, that NASA has largely come out of cryogenic storage and is showing signs of a fully functional intelligence.


    Only signs? Sure. Donald Becker (who also worked at NASA) didn't just complain about problems with the network drivers - he wrote his own damn drivers, and it took a very long time for anyone to come close to writing drivers even a fraction as good. Nor did he complain about the lack of clustering capability, he wrote his own - bproc - and the supporting tools that collectively became known as Beowulf.


    And the rest of NASA's problem is...? Sure there are bugs in the kernel. And NASA has a small army of programmers fixing inconsequential bugs in old Fortran code that has been in solid use for 20+ years. Let's say that NASA held a 2 month bug-squelching fest. It might still not get Linux to the point where Goddard or JPL were willing to use it on production servers in general, but I'll bet you anything that:


    • It'll mean the Fortran codes running on Linux boxes will run more reliably, for less effort, than could have been achieved by continuing to fix the Fortran for the same length of time
    • It'll inspire the regular kernel developers and may even encourage those on the fringes to become kernel developers
    • As most servers don't need the full range of capabilities, NASA will be able to produce a rock-solid "micro Linux" designed specifically for specialized servers


    NASA has made a big difference to the software available for Linux (at least, if you're interested in moving objects), and in the distant past made a revolutionary difference to Linux networking. They could make a revolutionary difference again, if they loosened up on the distribution of their Open Source and/or got another Donald Becker to get some critical segment of the kernel working absolutely perfectly. I'm not holding my breath, but there is so much potential there that they'd be foolish to ignore it.