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Ask Slashdot: Best Rapid Development Language To Learn Today?

A program like the grandparent's "Hello World" is meant as a starting point and not a demonstration of how small a nearly-useless program can be. A GUI program necessarily aims to do more than just print a message, and this example gives you a small glimpse at how you the language could look and feel, and how you might go about doing something more practical. A MessageBox popup is not a good starting point since about all you can change is the text itself.

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Re:Protecting the Weak from the Strong (224 comments)

Do you have personal experience with this? Are there any data on that? How many lives are saved per year by the threat of gun violence?

In the absence of a study, imagine a world in which every citizen (maybe older than, say, the legal driving age) is carrying a firearm. Imagine the major population centers like NYC where the statistics would matter. Would there be fewer gun-related deaths in that world than in ours? I can't see it that way. I would feel safer in a world where people are more encouraged to deal with conflict in a nonviolent way.

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Happy 95th Anniversary, Relativity

Re:Simultaneity is in the eye of the beholder. (120 comments)

Re: Mercury's precession, I'm still a believer in Vulcan.

Yeah, even the term "disproves" is not exactly correct. Newtonian gravity has a very hard time explaining Mercury's precession and is completely untenable with today's observational evidence. General relativity explains Mercury's orbit without having to invent new invisible planets & stuff. And today General relativity is still doing spectacularly well with many careful neutron star observations as well as experiments closer to home, like Gravity Probe B's measurements of frame dragging and more.

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Happy 95th Anniversary, Relativity

Re:Simultaneity is in the eye of the beholder. (120 comments)

Funny, I read that book (which is excellent) but don't remember that analogy. But I think you're talking about special relativity, not general relativity. The best GR explanation I've seen is an article Lost in Hyperbolia. For me that explanation worked perfectly.

Now I remember reading in various places that the solar eclipse data on GR was not actually conclusive. Bad science. The earlier work Einstein did that explained the precession of mercury's orbit was actually the first confirmation of GR. Also, of course, confirmation is not a word that is ever used correctly in science. The precession of mercury's orbit disproved Newtonian gravity but failed to disprove GR. The bending of starlight by the Sun would have been an even more impressive failure-to-disprove GR if the data were actually conclusive.

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Lectures Aren't Just Boring, They're Ineffective, Too, Study Finds

Re:I've heard slashdot is behind the times... (166 comments)

I guess I need to read through the studies some more, but I believe that most/many indicators of education show that lecturing is poor (relative to other methods) regardless of the particular talents of the students. Yes, I have felt that I've gotten a lot out of certain lectures. Some lecturers are definitely better than others. Certainly both student and professor abilities can make a huge difference, but on top of that a professor can still do better by adopting a hybrid approach.

Lecture for a bit (less than 10 minutes, maybe 15 tops), then switch it up. Have students work a problem (maybe in pairs) and vote on a solution. With smallish classes you can use simple voting methods, and with 100+ groups you can use electronic voting. Have short, focused discussions. Do a demonstration that includes volunteers. Have students research related topics and present their own mini-lecture (small classes only). And so on. Even if the professor is a great lecturer and the students are all highly disciplined and auditory-sequential learners (almost never true for an entire class), they would *still* benefit more from this kind of approach. It certainly takes more work on the part of the professor and involves some retraining, but students are paying a lot of money for their education and they ought to be treated as valued customers a little bit more. I've tried these approaches myself in undergraduate physics classes of various levels from gen-ed courses to the introductory sequence and up to the jr/sr level. I won't claim to have mastered anything but it quickly became obvious to me that lecturing for an hour is never the best way to teach. There are alternatives and a conscientious professor owes it to their students to pay some heed to the learning sciences and experiment with different approaches. It's not a one-technique-fits-all kind of thing, but anyone can improve upon pure lecturing.

I heard of one professor that met a student wandering the halls at the end of the semester, looking for their professor. He asked him where this certain professor's office was -- they were preparing for the final exam and had some questions. He said "I'm your professor. Have you seen me before?" Obviously this student didn't feel that the lectures were an efficient way for them to learn.

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Lectures Aren't Just Boring, They're Ineffective, Too, Study Finds

Re:I've heard slashdot is behind the times... (166 comments)

But studies have been finding this for the past two decades.

My thoughts exactly. This is apparently a new study, however. It's not clear to me what is new about it other than, perhaps, translating the results into letter-grade equivalents. I like the quote: "it’s almost unethical to be lecturing if you have this data."

And yet, as you point out, this kind of data has been around for decades at least. I think they knew in the 80's if not earlier that knowledge retention is terrible for students listening to lectures compared to other methods (reading, group activities, teaching, etc). But how many professors took that data to heart? Is it a matter of couching it in different terms like letter grades? Probably not because those professors who lecture today either don't know or don't care. In either case they are immune to new studies like this.

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How 'Fast Lanes' Will Change the Internet

One problem is that folks have to pay Comcast for decent internet service, and also they have to pay Netflix for a subscription. Fine of course, but if Netflix has to pony up extra fast-lane and direct-lane fees, ultimately their subscription prices increase. So Comcast+Netflix customers essentially get a hidden charge for their video streaming, one directly to Comcast and the other indirectly to Comcast (through Netflix). The real problem is that the indirect fee also applies to DSL and satellite customers, so you can't even avoid this fee by choosing a Comcast competitor.

I can understand wanting a free market system to avoid tragedy-of-the-commons types of issues with Netflix customers causing other non-streaming subscribers to get worse performance, but this present "solution" is clearly broken and gives Comcast and other last-mile providers a significant economic influence over other companies like Netflix that does not derive from consumer choice.

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The Koch Brothers Attack On Solar Energy

I think there are at least two underlying problems here. You point out one: corruption in the form of campaign finances and lobbyists. The other is the outrageous effectiveness of propaganda. I don't hear much about potential solutions to this second problem, and it's perhaps more difficult to solve. It might help to have some kind of propaganda analysis/deconstruction as part of a standard curriculum in high school, but that wouldn't be enough. We also need some watchdog-type media coverage that picks apart and shames people using such blatant propaganda techniques. Obviously TFA is just such a thing, as are programs like The Daily Show etc. These are good but not yet spread widely enough across the political spectrum.

Ideally a large fraction of voters need to be able to identify propaganda whenever they see it. And they need to react negatively to it, more than logic demands, overcompensating for the rest who get suckered by it all. Unfortunately, nearly all political campaigning is so densely infused with propaganda that we get accustomed to it. If all advertisers and all politicians do this all the time, there's no person more shamed than any other.

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Time Dilation Drug Could Let Heinous Criminals Serve 1,000 Year Sentences

If one cannot be "redeemed," why even serve long sentences? I can only think of four possible goals or outcomes of a penal system. One is revenge, which seems entirely without merit (to put it mildly). The second is deterrent, to reduce crime by fear of punishment. The third is protection, to remove harmful elements from an otherwise-healthy society. The fourth is reformation/rehabilitation, so that individuals can once again participate in society in a positive way. Both of these latter goals get difficult to define when you have to get detailed or specific, but in a broad, general sense they seem reasonable to me.

I don't see the fourth goal being very effectively accomplished by penal systems today. The first two on this list are at odds with the fourth to a large degree. If you torture or drug prisoners to think they've served a 1000-year sentence, there is probably no way for them to return to society after having been driven mad with isolation, boredom, and anger. Capital punishment would better serve the first three goals unless, like the article's author, you feel that death is too good. If redemption is ever not a realistic possibility, I don't see a better alternative than death.

On the other hand, death is irreversible and courts do not always correctly determine guilt. A disturbingly-large large fraction of death-row inmates have been proven innocent.

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Ask Slashdot: Online, Free Equivalent To a CompSci BS?

Just to counterbalance this, I recently switched from doing academic physics research to a programming career. Now I'm a senior software developer with a wide variety of experiences (currently Android internals). I've taken exactly one comp sci course: data structures. That course was helpful but habitually writing, reading, and debugging code has taught me most everything I've needed. Reading code is very important, as is starting programming at an early age and applying it to whatever you're doing. Learning a variety of languages is also important as each one brings its own paradigms. I read a patterns textbook once but didn't see anything that I wasn't already familiar with. I just learned terminology from that.

Still, if one is new to programming I'd have to think that getting a degree one way or another would teach a lot in a short period of time. I had never really thought of programming as a profession but rather as a tool that was necessary to whatever else I wanted to do. Economic pressures turned my hobby into a profession. I'm still just a bit grumpy about that even though I'm having fun.

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I would naively have expected that cuts to NIH programs would have low impact relative to programs funded by NASA and DoE. I don't have much knowledge of the NIH programs, but I feel like they are shorter term studies with less specialized infrastructure involved. So a 5% cut in funding there has closer to a 5% reduction in output. But DoE and NASA programs are often 10 to 20-year projects. If you cut funding one year (and they have cut funding 5-10% every year for a long time), you start cancelling programs and losing the money already spent. An oversimplified model would be that if you fund one of these agencies for, say, $5B for 8 years,$2B the 9th year, and then $8B the 10th year you'd get$20B worth of "output" not the $50B you've spent. In year 9 programs get cancelled, equipment mothballed, and people leave the field. about 5 months ago top Does Relying On an IDE Make You a Bad Programmer? Re:Does using a saw make you a bad carpenter? (627 comments) I agree with most of this, but I still use emacs a lot. Sometimes an IDE can become an impediment if it keeps you from looking at hard-to-find code, makes you in any way lazy about debugging, or helps you read through code too quickly (making happy assumptions). I'm currently working on an Android system and regularly have to jump between application code, Android internal services and components, various JNI or hardware abstraction layers, and kernel code. Sometimes I need to read through standard C library implementations too. So while I like doing some things in eclipse, most of the time eclipse is not configured to let me dig deeply enough or follow calls all the way through the framework. Similarly the interactive debugging utilities are often limited and I resort to reading code and adding print/logging statements. It feels old-fashioned sometimes but on the other hand I have no excuses or reluctance to work hard enough to get a deep understanding of the whole system. So I'd judge an IDE by its ability to help you quickly navigate around a large and maybe unfamiliar code base. A good programmer's #1 job is probably reading code carefully and accurately. Features like auto-completion and live error checking are much less important. Also keep a tab on the amount of time it takes to keep your IDE configured correctly and able to compile independently from a more automated build system. Don't let it become a timesink, crutch or an excuse! about 6 months ago top Can Electric Current Make People Better At Math? Math concepts unrelated to computation skill (112 comments) I read "...and improve their understanding of math concepts" with a lot of skepticism. I think that schools love to teach computation skills because they are easy to teach and because success there is very easy to measure. But this skill is relatively unimportant compared with what I would consider "math concepts": How you apply mathematical abstractions to real-world situations (beyond making correct change at a cash register). How you break down a hard problem into less-hard pieces. How to visualize quantitative relationships, develop and use algebraic systems, and so on. These are rarely taught in schools because they are relatively difficult to teach and difficult to measure gains. So computation skills are taught instead, regardless of the fact that cheap computers are billions or trillions of times faster than any human. Can electric current apply to this kind of conceptual learning? If so, it would have application to nearly all kinds of education, not just math. about 6 months ago top How Good Are Charter Schools For the Public School System? Re:Test scores (715 comments) I think one of the major problems with standardized testing is that the scores are over-used. Scores are used for evaluating students, teachers, and schools. Each group has incentives attached: scholarships and admissions for students, salaries and job opportunities for teachers, and higher funding levels for high-performing schools. If these incentive systems were decoupled instead somehow, then meaningful analyses of scores could be made. I agree that assessment is important, but it's a very difficult problem that we have not solved. Is it better to use a broken approach than have no assessment at all? I personally think that testimonials and self-evaluations are currently more meaningful than test scores in general. Standardized tests usually measure only those outcomes that are easy to teach and test but are unimportant in real life. Mathematics is an easy example of this. My 6th-grade daughter gets homework sheets that are mostly repetitive exercises to boost speed. A recent example was computing the circumferences and surface areas of circles. Calculators were allowed in this case, so it was an exercise in key punching. Then we went to a pizzeria a few days later and she was happy to compute the circumference of a pizza (without prompting -- her idea). So I asked her "about how many bites would it take to eat a whole pizza?" She didn't know how to work that out, thinking that she was not taught how to solve that kind of question. I wasn't giving her one of the needed inputs, the size of a bite. And also her understanding of surface area was not strong. The problem here is fairly universal: Math students are taught the abstract computation skills but not synthesis of this knowledge. It is very easy to test how quickly students can compute things and even how fast they can look up formulas that match the given knowns with the required unknown, but these are meaningless skills without also learning how to bridge from the abstract to the real, and how to form connections between the principles they learn. Students should be given harder problems that they have to puzzle over, even starting in grade school. It's okay if they don't get the right answer or if they get stumped, as long as they were able to begin to think productively about them. This builds genuinely-useful math skills and hopefully a certain discipline of thought that is not usually innate. This ability to apply math to real-world situations, and by algebra to think of math as a language, is much harder to assess than timed multiplication tests and so it is generally avoided. If a teacher were to spend time on this kind of development in place of the repetitive speed drills, their students would perform worse on standardized tests. The teacher's students would suffer, as would the teacher and their whole school to some degree. So, is standardized testing better than nothing? I think that yes, it is, but on the other hand almost any other form of assessment would be better still even if it were not standardized. about 7 months ago top Simulations Back Up Theory That Universe Is a Hologram Re:A projection of what? (433 comments) Mathematics, especially in this context, is just a language for expressing ideas. So I think that in some sense it is possible that some particular string theory really does describe what's going on. I don't know if it's very likely, but the idea of a "final theory" is that it is, in some sense, a complete and accurate description of our universe's mechanics. (The holographic principle is nice because it states that two seemingly very different theories can actually be equivalent.) I think there are two main caveats here. One is that you never really know when you're "done", and have a theory that is indeed final. We know now that we are not done today because of inconsistencies, but science also does not have even the capability of perfect validation. The other is that a microscopic, reductionist description of physics is not useful or even the correct language for describing more macroscopic effects since basically "more is different." Chemists don't use quantum field theory because it's just not helpful. And while it's great (even important) to consider philosophical ramifications of theoretical work like this, we have to remember that it's all still conjecture and it will probably always be conjecture. The philosophical spin-offs, so to speak, should never be taken as a way of either supporting or condemning the theory. I think I'm basically summarizing some of what Wienberg describes in his book Dreams of a Final Theory (1993). That seems old but I highly recommend it! about 8 months ago top Physicists Plan to Build a Bigger LHC Re:WHY NOT IN THE FIRST PLACE !! (263 comments) That depends on what you mean by "tangible benefits." One argument I've heard for practical, what's-in-it-for-me-today benefits is that the technology produces spin-offs such as techniques to mass-produce rare-earth magnets, the world-wide web, etc. But that's honestly a weak argument because there's a lot of research going on that has similar chances to produce spin-off tech. For particle physics, the feeling is that we are on the verge of some kind of revolution! Admittedly it's been that way for a few decades now, but the current working theory (the standard model) has a number of deep problems (thanks wikipedia!). Most new theories, and there are a whole lot of them, predict new phenomena just at the edge of our experimental reach. Part of that is because well-meaning theorists prefer to propose theories that are either presently or soon-to-be testable. But part of it is because the experimental frontier has advanced to energies at roughly the electroweak unification point and lots of theories have interesting behavior to predict at this point, broadly speaking. So it's not just a more-is-better kind of effort that won't stop until we build solar-system-sized accelerators. There really is a sense that a major shift, possibly even a philosophically-challenging development, is nearly within our grasp, within our lifetimes. This is not a "practical" argument for basic science, but only history can tell us what has had short and long-term practical benefits. History does tell us that this sort of pursuit has in the past been enormously beneficial. Maybe we are in a whole new era where new physics will be completely impractical, but that would honestly be surprising if true. about 9 months ago top Physicists Plan to Build a Bigger LHC Re:Question... (263 comments) You hit numerical problems if you calculate it that way. Wikipedia gives a series expansion that works well for large values of gamma: v (in units of c) = 1 - 1/2 \gamma^(-2) v = c (1 - 1.8e-10), or 0.99999999982 c about 9 months ago top Physicists Plan to Build a Bigger LHC Re:Peanuts (263 comments) I don't think in these cases you have multiple labs bidding for the job. You have multiple countries wanting to host the lab, but that's a different story. The biggest problem for high energy physics is establishing multi-year funding. The US government cannot promise anything beyond a single year of funding. If say$8 B has been spent over 10 years and one year congress says "but I promised to cut spending", then that's the end of the road for that lab. This happened for the SSC in 1993, but also a lot of times since then on lower-profile, some $500 M experiments that were, yes, in construction already. Now say 15 years later the$10B has been spent, but its not quite done, another $2B would let you finish the project. Do you really throw away$10B to save 2B? There is no fraud, just a mis-estimation of the costs of building a beyond state-of-the-art machine and slightly larger technical problems than were expected.

Most of the cases I'm familiar with, including the SSC, were not actually budget overruns even though they were politicized that way. If you're a politician who wants to (a) publicly demonstrate how fiscally conservative you are and (b) not actually cut spending on items that might affect the bulk of your constituency, then you cut big science every time. Even if the budget grows on the whole, you've made a statement and some headlines.

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A mathematician is a device for turning coffee into theorems. -- P. Erdos

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