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User: mea37

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  1. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 1

    Congratulations on missing the point and posting an almost-correct reiteration of what's going on with this proof. Since you couldn't be bothered to understand the context the first time, I'm not going to try to explain it to you, but you're welcome to go back and read the conversation again until it makes sense.

  2. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 1

    Based on replies, your opinion is popular; unfortunately it is incorrect.

    As I stated in my original comment, sqrt() is a function. All functions return exactly 1 output for each input. You are confusnig the sqrt() function (which returns the principle square root) with a multi-valued operation that returns all square roots.

  3. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 1

    Incorrect. sqrt(1)=1 by the definition that sqrt(1) is the principle square root function. In written notation, if you mean to indicate all possible square roots (of a real number), then you put a +/- in front of the radical.

    There's nothing wrong with taking the sqrt() of an imaginary number, but there is something wrong with thinking that i^4 is an imaginary number. sqrt(i^4) is not i^2.

  4. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 1

    True-ish. The purpose of the imaginary numbers is to hide the mistake in notation that will appaer correct to most people. If I had written

    (-1)^2 = 1
    sqrt((-1)^2) = sqrt(1)
    -1 = 1

    then everyone looking at it would've said "no, sqrt((-1)^2) is not -1", because that is a property of real numbers that is taught at that level. But with i, there's no tell-tale negative sign under the radical to alert people that you're about to pull a fast one.

  5. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 1

    Well, not quite. What you're suggesting is related to my explanation that for a=b to imply sqrt(a)=sqrt(b), we must interpret sqrt() as the principle square root function. Every number has only one principle square root, and for 1 the principle square root is 1.

  6. Re:I went one further on Proving 0.999... Is Equal To 1 · · Score: 3, Informative

    People assuming they did something wrong when the result "doesn't make sense" isn't the problem.

    People failing to distinguish between a notation and a number, creating the belief that "0.99(9)=1" doesn't make sense, is the problem.

    Consider this proof, which follows simple steps to reach a conclusion that doesn't make sense:

    i^2 = -1 (definition of i)
    i^2 * i^2 = -1 * -1
    i^4 = 1
    sqrt(i^4) = sqrt(1)
    i^2 = 1
    -1 = 1

    Then if you want you can add 1 to both sides and divide by 2, to find 0 = 1.

    Now, do you know why this proof is bogus? When I was in high school, we were introduced to imaginary numbers, and I drew up a slightly more obfuscated version of the above; it had a lot of people (including a couple relatively sharp teachers) in "I know you did something wrong because the result doesn't make sense" mode for a long time.

    The fault, of course, lies with the sqrt() step. For a=a to imply sqrt(a)=sqrt(a), we have to interpret sqrt(a) as the pricple square root function, so sqrt(x^y) = x^(y/2) doesn't necessary work when x isn't a real number.

    Without the motivation of "this result cannot be right", I wouldn't have puzzled this out. More than that, the solution comes from understanding that rules we take for granted only apply to certain types of number. Applying that to 0.99(9), it's easy for people to convince themselves that repeating decimals are a special class of number subject to "some rule I just don't know".

    But in this instance, that reasoning is flawed, because .99(9) really is just a regular real number in a weird notation.

  7. Re:Hmm on Pope Says Technology Causes Confusion Between Reality and Fiction · · Score: 1

    If you're the sort of person who naively believes that nothing can be learned from fiction, then I understand your reluctance to care whether someone keeps various stories straight. But then, if that's your mindset you probably aren't receptive to the most valuable lessons of any philosophy.

    Ah, but you weren't really looking for an answer, were you? You were just hoping I'd be fundamentalist enough to get pissed off when you refer to the Bible as fiction, eh? Nice try.

  8. Interseting timing on Gambling On Bacteria · · Score: 1

    I was recently in the position of commenting on an analogy a friend was putting together describing DNA-related processes like transcription. My primary criticism was that certain processes were anthropomorphized. Representing cellular processes (or, more generally, chemical processes) as human activities and "decisions" tends to create confusion about what's really going on.

    And within a week or two of that, I find myself reading a story that bothers to ask why indiviual bacteria don't "try to save themselves". Well, let's try not thinking of them as human beings with self-awareness and instincts geared toward indiviual survival - much less as humans with individualistic views traditional in the Western world.

    In fact, why are we even calling the cellular responses of bacteria a "decision"? It's not - it's a stimulus response. A complex one, to be sure, but even remotely comparable to human decision-making only if you reject free will. (Even if you do reject free will, the illusion thereof is strong enough that the comparison of this bacterial "decision" to human decisions hinders comprehension rather than aiding it.)

    If we must compare bacteria to humans, let's do it this way: Compare an individual cell in a bacteria colony to an individual cell in a human (or other complex organism). Compare the whole of a complex organism to the whole of the colony.

    If you do that, then suddenly the story's hook about applicability to gambling - or even the relationship to game theory in the first place - seems a little bit thin.

  9. Re:Hmm on Pope Says Technology Causes Confusion Between Reality and Fiction · · Score: 4, Insightful

    It's rather evident you didn't read the old version either, if you think it was Moses who was asked to sacrifice his son.

  10. Re:Obvious? on Saturn's Rings Formed From Large Moon Destruction · · Score: 3, Insightful

    Really? Not new science because it seems obvious? Because after all, everything that seems obvoius turns out to be scientifically correct, right?

    For example, to move from point A to point B, an object must move through all the points in between. Oh, except that's not true on a quantum scale.

    And if you're on a train that's moving at speed X, and you walk toward the front of the train at speed Y, then you're speed is X+Y. Except if the velocities are large, that will yield a measurable error.

    And a little closer to home here, we "knew" for quite some time that 9 objects were unique in the solar system. To many people this was so obvious that they won't accept it as wrong, even though we've since figured out that one of them wasn't like the others, and was more like a vast number of other objects.

    What we 'know' about planets' ring systems is speculation - a suitable answer to give an elementary school student who asks, so long as you preface it with "we think that this is the explanation".

    A new model is new science. It refines the hypothesis well beyond "debris caused by collisions". That it confirms, rather than refutes, the suitability of the (refined) hypothesis doesn't make it any less new.

  11. Re:Why only 25 years on 15-Year-Old Boy Fitted With Robotic Heart · · Score: 1

    So people keep pointing out, and yet it ducks the perfectly valid question that is raised by the vague wording of the article.

    Since his condition could well kill him in less than 20-25 years even with this heart, a lot of us suspect that the 20-25 year figure has to do with the life of the device. Yet if that means that a person (maybe not this person) could live out a term limited only by other factors by having a new heart implanted every 20 years, I'd think you'd say so rather than suggesting that the device gives you up to 25 years.

    Now maybe that's because the implant procedure for some reason can only be done once in a given patient. Or maybe there's a practical age limit on surviving the implant. Or maybe a lot of things. The point is the article raises qustions, people are asking the questions, and if you don't know the answer then taknig an easy out by parroting the reason its moot in this case is no better than keeping quiet and waiting to see if someone with knowledge comes along to respond.

  12. Re:But.... on Court Rules Against Woman Who Didn't Like Search Results · · Score: 1

    Actually, that may be a good question (but IANAL). The judge apparently didn't see it that way, but we don't know how the matter was presented by the lawyers; maybe a case could be made. Ultimately the judge is saying she didn't show that she had a commercial interest in her name; maybe she didn't assert an interest in her name as it appears to a job interviewer, or maybe her circumstances don't lead the judge to believe that will be a problem for her (e.g. if she's disabled, or a stay-at-home mom, or retired).

    But to put this in context, the Lanham Act is trademark law. I'm not sure I want to think about the consequences if everyone is said to have a trademark in his or her own name. If you want to argue that a web search hurt your reputation, that's probably more properly a defamation issue - but good luck with a defamation suit in the U.S. IMO your best bet would be to hope people interviewing you have more sense than to assume you're assocaited with every link that comes up when they search for your name. (In other words, the issue you raise may be more social than legal.)

    15 U.s.C. 1127 (construction and definitions, intent of chapter) would seem like the most obvious place to look for terms that limit the scope of the law. I don't see anything there that makes it clear to me why your argument wouldn't hold; but again as IANAL it doesn't mean much that I don't see anything there, plus the limiting clause could be tucked away elsewhere in the law (among other places).

  13. Re:But.... on Court Rules Against Woman Who Didn't Like Search Results · · Score: 5, Insightful

    More likely the judge is just using the most open-and-shut logic applicable in order to put this to bed at minimal cost to all involved. My gut reaction was that this was a Bad Thing, as it left the door open for other litigious behaviors; but when I thought about it, that's the right thing for the court to do: address the case at hand, narrowly.

    Probably we could have a grand old time arguing about who's responsible for keyword associations, and who owns what, and on and on... but when the law in question can be quickly shown as inapplicable by examining a single fact, what's the point letting her dump money into an effort that forces Yahoo and the taxpayers to spend additional money as well?

    If she's really committed to wasting resources, perhaps she'll have her lawyer come up with another theory with which to bring a suit that cannot be so quickly set aside; if so, I guess the fun will start anew.

  14. Re:It doesn't take much delusion... on Verizon Wireless To Issue $90 Million In Refunds · · Score: 0, Troll

    Wow. You're anti-corporate but can't do better than that old crutch of an argument?

    First of all, "ethical" and "moral" are not interchangable as you seem to think they are. Fortunately it doesn't matter, because neither moral nor ethical requirements (nor legal ones, for that matter) are overridden by an executives fiduciary duty to the shareholders. The only people who think it is are those who want an excuse to hate executives and assume that everything they do is illegal.

    Want to prove me wrong? Buy some shares in any major corporation of your choosing, and try to initiate a shareholder lawsuit alleging that the company could've stolen more money for your benefit. Let us know how that works out for you.

  15. Re:And? on Verizon Wireless To Issue $90 Million In Refunds · · Score: 1

    You say it would be nice to think it's incompetent, but it sure sounds like you'd rather think they're out to get you.

    I have no problem at all believing that a billing system, which has many dynamic provisions for adding charges but probably only one or two pretty simple methods for adding credits, would tend to error in the company's favor.

    An error in the company's favor is defintiely more likely to be noticed. If I don't use data but I see a 1MB data charge on my bill, I know something's screwed up. If I use data but the reported usage on my bill is 1MB lower than it should be, will I even know? Even if I've been keeping track and I think I know what you'll bill, I might just assume I was wrong about how you round usage.

    And I bet if you think about it you'll have to agree that an error, once noticed, is more likely to be reported if it's in the customer's interest to report it.

    But sure, in spite of all that, let's look at the fact that the stories never talk about a rash of under-charges as proof of a conspiracy.

  16. Re:And? on Verizon Wireless To Issue $90 Million In Refunds · · Score: 5, Insightful

    '$90 million was no "accident."'

    Maybe it wasn't, but I find this "matter-of-fact" statement amusing. What, the fact that it's a large number makes the idea of an error impossible? A systematic error in their billing system - the kind of thing I have no problem believing would slip past a corporate QA department - could easily rack up $90M across the book of business before being noticed.

    IT makes it possible to do everything - including screw up - a lot faster than you would imagine.

    'This is all standard operating procedure'

    Citation needed. If you've ever actually worked in a corporation, then you know that the management will do all manner of unethical thing, but only to the extent they can delude themselves into believing it's really ok. I've yet to meet an executive so far gone that he believes you can overcharge your customers and then repay the principal when you get caught. They like to be a lot more subtle than that.

    'The telecoms are all resisting FCC inquiries'

    All companies resist all manner of oversight. Oversight costs money even when you're following the rules. This doesn't mean that there should be no oversight, but it does mean that a company cannot be presumed guilty for trying to avoid oversight.

  17. Re:WTO? on Why the Revolution Will Not Be Tweeted · · Score: 5, Insightful

    What I'm about to claim is a fairly subtle distinction, but bear with me as it makes a big difference.

    Overuse of protests has not made protests weaker. You might say it has produced an increasing proportion of examples in which protests are ineffective. The distinction is in the causal relationships.

    It isn't that using protests as an everyday tactic leads to weak protests. It's that protests are effective for certain types of cause. Use of protests against other types of causes will lead simultaniously to two symptoms: many protests, and weak protests. So yes, you see a correlation between frequency and weakness, but it is not because one causes the other.

    The difference is, even today if 60's-style protest tactics were used against an appropriate opponent for an appropriate cause, they would work as they did then. A nonviolent sit-in draws much of its strength by painting a salient moral picture in the public eye. It creates a confrontation, and observers see one side peacefully asserting their position and being bullied by the other side. This can be used to mobilize public opinion.

    But when you use the same tactics to oppose 'the man' not because he's the kind of person that would turn a fire hose on you, but because that's how you want to perceive him... well, then you have a problem. He never attacks you, never cedes the moral high ground, and the whole incident goes unnoticed.

    The risk faced by the 60's activists was a key factor in their success, because their function was to shed light on exactly that risk as a symptom of the social status quo. Take that risk element away (by applying the tactics to the wrong kind of adversary) and you increase the number of protests - because it's easier to get people to join in - while reducing their effectiveness.

    In part, this implies that the effectiveness of a protest is related to the character of the group being protested. Could the pro-segregation establishment have ignored the sit-ins to cause them to go away? Well, no, because of the alignment of those protests as a defiance of "the rules" - not just a statement of dissent. For four black students to sit at a "whites only" lunch counter, they were assured an aggressive response at some level because their protest, unchallenged, was not harmless to the status quo. For the establishment not to respond would be to concede - "you really can sit here".

    But by contrast if a group stands outside an abortion clinic with picket signs, how does that force any response at all? Such a protest is usually ineffective not merely because it is perceived as a lesser threat to the establishment do to overexposure, but because it is a lesser threat by its own nature. Unlike a lunch counter sit-in, the only way for either side to "lose" in this confrontation is to be the first one to turn violent.

  18. Re:Sorry forgot account details on Senate Votes To Turn Down Volume On TV Commercials · · Score: 1

    LOL slashdot posters are so silly. How long dod P think about flaming GGP about not understanding what a compressor is, without even understanding what it is?

    The problem is caused by upward compression. It can, however, be solved with downward compression. If this is done with the correct parameters, the result will be tolerable audio volume, plus advertisers are punished in proportion to how much upward compression was used in the first place because the two rounds of compression dramatically degrade their dynamic range; so now instead of "shouting" at you, the spokesjerk is talking at you in a very flat voice.

  19. Re:Uncharacteristic: on Senate Votes To Turn Down Volume On TV Commercials · · Score: 1

    People have said for decades that they won't buy products with such-and-such tactic that they find annoying. Many such tactics are still in use. What does that tell us about your solution?

    I mostly agree that a new law isn't the best solution, but I don't share any sense of outrage about it. It's not like this is "new" regulatory territory; it's just a new regulation in a field already federally regulated (e.g. by the FCC). The "fear of going deaf" statement so overstates the problem that it highlights how minor it really is, and if we were talking months of debate and a 2000-page bill I'd be outraged at the waste of time and effort; but as it is, this just doesn't stand out among exercises in government time-wasting.

    My preference would be a technical solution. Building downward compression controls into the receiving set and selling that as a feature seems workable to me.

  20. Re:uhm, 30 000RPM? on Levitating Graphene Is Fastest-Spinning Object · · Score: 1

    I guess I shouldn't complain, but I have to wonder why my dumbest jokes are getting mods like "Interesting" lately... This is worrying.

  21. Re:Attach parachutes.... on Govt To Bomb Guam With Frozen Mice To Kill Snakes · · Score: 1

    Well, either you're right and it won't work at all; or the team that's actually studied the problem and run tests is right and there's a good chance that any such problem has been overcome. (Can you guess whom I think is more likely to know what they're talking about?)

    But the ultimate success or failure of the plan is beside the point. Focus. I was responding to a claim about natural selection. The claim was based on elevation of natural selection to a mystical process that will maek a species survive anything that happens. That's not how it works. If you're right, then the species will survive due to a trait that's already dominant; no adaptation required, no temporary period where the plan seems to be working.

    In an environment where evolution as a theory is under attack, misrepresenting it as a panacea is a Bad Idea.

  22. Re:uhm, 30 000RPM? on Levitating Graphene Is Fastest-Spinning Object · · Score: 2, Interesting

    If only they'd thought to attach their single microcrystal to a brushless motor...

  23. Re:Abuse on Unseen Moon Landing Video Released · · Score: 1

    Dawg?

    As in: "Yo, dawg, I heard you like paradoxes, so I put cyclical time in your universe so you can kill your grandfather while your grandson kills you!"?

  24. Re:Abuse on Unseen Moon Landing Video Released · · Score: 1

    How would a story set in the 60's be a prequel to stories set a long time ago in a galaxy far away?

  25. Moon Landing SE? on Unseen Moon Landing Video Released · · Score: 3, Funny

    "high-quality and brighter images of Neil Armstrong stepping off the ladder"

    Oh, good, the remastered moon landing. In a year or two we'll get the special edition, with all new special effects. The once-lifeless moon will have all manner of alien life. Probably the golf ball will swing first at the astronauts.

    Additional footage of the astronauts' training will be released, but it will be unpopular with fans of the oringal moon landing. Much of the criticism will focus on a goofy sidekick they meet, who somehow seems to play an important role in spite of being a babbling fool.

    Later there will be a DVD release with the SE footage alongside the video as it originally aired. HD and 3D versions will follow eventually.