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User: goombah99

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  1. Babinet called, wants his principleback. on 'Darkness Ray' Beams Invisibility From a Distance · · Score: 5, Informative

    I think they must have skipped the chapter in their basic handbook of optics called Babinet's principle. Because they just re-invented Babinet focusing.

  2. Re:Not possible. on NSA Head Asks How To Spy Without Collecting Metadata · · Score: 5, Funny

    Siri, find all the terrorists in the US.

  3. Re:90% of the cells in the human body on Bots Now Account For 61% of Net Traffic · · Score: 1

    It exists to serve us.

    You must be new here.

    And you have never seen "To Serve Man".

  4. 90% of the cells in the human body on Bots Now Account For 61% of Net Traffic · · Score: 5, Insightful

    are bacteria. Viewed that way, basically humans exist to transport and feed bacteria. However that's 90% by cell count, not cell mass or total DNA. Looked at it that way the bacteria are assistants.

    The bot traffic is light weight it outnumbers human traffic in site visits not byte counts. It exists to serve us.

  5. how does this work on on Estonia Sharing Its Finnish-Made E-Government Solution With Finland · · Score: 1

    how does this work on days when it isn't working? All service "access" cards are inherently also service denial systems if you don't have a card or the access system is down. Is their a fail over system available to every service access point?

  6. reprehensible on Disqus Bug Deanonymizes Commenters · · Score: 1

    The original topic poster wrote it like what they did was for a good purpose. While I might like journalists to do investigations of politicians I dislike bursting peoples trust in anonymity.

  7. Megahertz myth and the 6502 on The Real Story of Hacking Together the Commodore C128 · · Score: 4, Informative

    THe 6502 was an amazing processor. the Apple II was also a 6502. Unlike it's near contemporaries, the 8086 and Z-80 (and 6800), the instruction set was reduced. It had only 2 data registers (A,B) and two 8 bit address registers ( X Y) and fewer complicated ways to branch. Instead it effectively memory mapped the registers by using instructions like, offset Y by A, treat that as an address and get the byte at that location. Because it could do all that in one clock cycle, This effectively gave it 256 memory mapped registers. It also didn't have separate input lines for perifprials, and instead memory mapped those.

    Nearly every instruction took a microsecond. Thus while the clock rate was 1 Mhz, it was much faster than a 4 Mhz 8080 series chip since those could take multiple cycles to do one instruction. Few memory chips (mainly static memory) could keep pace with that clock rate so the memory would inject wait states that further slowed the instruction time. The 6502's leisurley microsecond time was well matched to meory speeds. Moreover, on the 6502 only half the clock cycle was used for the memory fetch. This left the other half free for other things to access memory on a regular basis.

    The regularity of that free memory access period was super important. it meant you could do two things. First you could backside the video memory access onto that period. On the 8080s using main memory you could often see gltiches on video displays that would happens when the video access was overridden by the CPU access at irregular clock cycles. As a result most 8080 series based video systems used dedicated video card like a CGA or EGA. Hence we had all these ugly character based graphics with slow video access by I/O in the Intel computer world. In the 6502 world, we had main memory mapped graphics. This is why the C64/Amiga/Apple were so much better at games.

    This regular clock rate on the main meory had a wonderful side effect. It meant you could use Dynamic memory which was faster, cheaper, denser, and MUCH MUCH lower power than static memory. With the irregular access rates of the 8080 refreshing a page of dynamic memory requird all sorts tricky circuitry that trried to opportunistically find bus idle times to increment the dynamic refresh address, occasionally having to halt the CPU to do an emergency refresh cycle before the millisecond window of memory lifetime expired. As a result, the 8080 seris computers like Cromenco, Imsai, altair and Northstar all had whopper power supplies and big boxes to supply the cooling and current the static memory needed.

    So the C64s and Apples were much nicer machines. However they had a reputation of being gaming machines. At the time that didn't mean "high end" like it does now. It mean toys. the Big Iron micros were perceived as bussiness machines.

    Oddly that was exactly backwards. But until Visicalc, the bussiness software tended to be written for the 8080 series.

    I think it was this memory mapping style rather than formal I/O lines to dedicated cards for periphrials (keyboard decoders, video, etc..) that lead apple to strive for replacing chips with software. they software decoed the serial lines (rather than using USART chips) they soft sectored the floppy drives rather than using dedicated controller chips, etc... And that was what lead to making the macintosh possible: less hardware to fit in the box, lower cost chip count, lower power more efficient power supplies.

    Eventually however the megahertz myth made the PCs seem like more powerful machines than the 68000 and powerPC.

  8. Re:it's like that and that's the way it is on A Link Between Wormholes and Quantum Entanglement · · Score: 1

    Explain me again why hidden variables are ruled out.

    because slice left-to-right rules out seeing X-Y from happening. Local hidden variables (i.e. it was X all along) can't create that ourcome (GLobal hidden variables due but these require spooky action at a distance to change B based on A's letter).

    Finally you can't have letter A changing it's state in response to the slice as a local variable explanation, because, I have a free choice if I open letter A first (and thus determine B's outcome) or I open letter B first and thus determine letter A's outcome. Without global hidden variables A cannot know if B was opened yet or not.

    Thus with local hidden vraibles seeing X-Y on a left to right slice would eventually have to happen. It doesn't.

  9. Re:I would like to turn my nerd card in on Tesla Would Be Proud: Wireless Charging For Electric Cars Gets Closer To Reality · · Score: 4, Insightful

    Moreover, none of the nerds here have noticed yet that Tesla would not be proud of this. He was trying to do wireless power across nations and oceans not inductive coupling at short range. Magnetic coupling falls off at very short range compared to propagating waves.

  10. Re:it's like that and that's the way it is on A Link Between Wormholes and Quantum Entanglement · · Score: 1

    Hidden variables can always explain all possible outcomes. Bell only showed that some types of hidden variables don't work. Whether you think that's definitive depends on how reasonable you find other kinds of hidden variables, compared to how reasonable you find non-local effects. The universe doesn't care how reasonable you find it, of course, and uses whatever mechanism it uses. We don't know what that is.

    Right. no Local Hidden varaibles

    There's no way the contents of the letters can predetermine the outcome. (i.e. No hidden variables can explain all the possible outcomes).

    Your example can be modelled using a hidden variable A that says "show X if opened left-to-right, show Y if opened right-to-left" and a hidden variable B that always shows X. Can you refine your example so it really can't be solved using hidden variables?

    Simple. I did not say which envelope I opened first. I can delay that choice till the envelops are well separated.

    I didn't say which envelope I opened first.

  11. Re:it's like that and that's the way it is on A Link Between Wormholes and Quantum Entanglement · · Score: 1

    Thanks, that is a nice one!
    One thing still bothers me with this: What if the second envelope had equal content to the first the whole time, but it just flips depending on the way you slice it open? That way, you can never prove that there is some entanglement, the association was made when the envelopes were created, and the flip (or not) to opposite is made only with local information.

    You prove this by delayed choice. You don't decide which envelope to open first till the envelops are far apart.

  12. Sounds like the apple lightning connector on Death to the Trapezoid... Next USB Connector Will Be Reversible · · Score: 1

    Apples blade style connector for iphone really nice. about as small as it can be, strong, reverisble.

  13. Another way to think about QM and Waves on A Link Between Wormholes and Quantum Entanglement · · Score: 4, Interesting

    Something that's a little bothersome is that when you are designing a video game that portrays a classical world, the physical limits of the computer end up imposing many of the physical laws we are used to.

    for example, consider diffraction limited resolution. Basically the further away something is, the less resolved it becomes. The bigger the eye or telescope you look through the more you can resolve at a distance. In the real world we call this diffraction limited resolution. In a computer game we call it pixels, and the bigger the monitor (in pixels) the better the resolution.

    To object oriented variables cannot simultaneously know each other's state. One of them has to be updated first. There's a finite limit on how fast the computer can alter the memory locations and it can't change both at the same time. So there's a kind of speed of light limit on how fast the world can change. If were doing this on distributed architectures or iterating serially over the objects then that limit actually shows up in the connectivity of objects with distance: nearer objects can influence each other sooner than remote objects.

    Finally, there is an exception to that rule. Two objects can communicate instantly if they share the same class variables. This is spooky action at a distance. While it's often claimed that quantum mechanics does not allow hidden variable theories , this is a mis-interpretation of Bell's theorem. In fact it only disallows local hidden variable theories. Global hidden variable theories are what QM says do exist. That's exactly how you get entanglement.

    So QM emerges because of the class variables, diffraction emerges because of memory limits and the speed of light comes out from serial processing at the CPU or memory access level.

    Thus you can't actually create a simmulation of reality that didn't have the characteristics of our weird world even if you wanted to.

  14. it's like that and that's the way it is on A Link Between Wormholes and Quantum Entanglement · · Score: 2

    To expand on your reply, here's a different letter game.

    you mail two letters with magic XY cards inside. When the first letter is sliced open the probability it shows and X or a Y is equal. If the first letter is sliced open left to right then the other letter will match the contents of this letter. If you open it right to left then the other letter will show the opposite letter.

    There's no way the contents of the letters can predetermine the outcome. (i.e. No hidden variables can explain all the possible outcomes). Notice also that this can't be used to transmit information faster than the speed of light. But by doing the experiment we can confirm that the choice of which way to slice changed the outcome of the remote envelope.

  15. Now google can oogle to your conversations on Google Launches Voice Search Hotword Extension For Chrome · · Score: 3, Insightful

    Just as google reads all your e-mail, not just what you search for, to "help you" get better advertising. they will no doubt listen to everything you say, not just what you search for, in order to improve their service to you. It's all about you.

  16. Won't this problem vanish with micropublishing? on Getting Evolution In Science Textbooks For Texas Schools · · Score: 1

    Why is this still a problem. Why can't the publisher's do a special run of their text books for Texas that includes whatever rubbish Texas wants, and then provide decent text books for everyone else? I don't see why, in the age of micro publishing, that there's any economy of scale here. So how does Texas retain this influence on the nation?

  17. Re:Embrace and extend on Google Is Building a Chrome App-Based IDE · · Score: 1

    Your slashot ID is low enought thatyou should recall that Internet explorer was available for the mac too. And doing everything from the browser was why MS invented its active scripts. http://en.wikipedia.org/wiki/Internet_Explorer_for_Mac

  18. Embrace and extend on Google Is Building a Chrome App-Based IDE · · Score: 2, Interesting

    Do you remember those words. That was how Microsoft set the web back 20 years by killing standards compliance. Now google is the evil.

  19. "investing" in bitcoin on Virgin Galactic Now Taking Bitcoin For Suborbital Flights · · Score: 1

    I'm "investing" in dollars but I don't call myself an investor. If you want to call bit coin an "investment" then you are treating it as a commodity with a futures market or a speculation on rising prices like gold. Which means it is definitley not a currency, whose halmark is stable value. Bit coin is not currency till people stop saying they invested or speculated on it's value.

  20. bend reality on Ask Slashdot: How Reproducible Is Arithmetic In the Cloud? · · Score: 5, Funny

    The result is always the same, but the definition of reality is changing. The result of every single calculation is in fact 42 in some units. The hard part is figuring out the units.

  21. SnapChat Roulette on SnapChat Turns Down $3 Billion Offer From Facebook · · Score: 4, Funny

    Images you can't forget but can't see after 30 seconds.

  22. When will chrome support 64 bit java? on Google Chrome 31 Is Out: Web Payments, Portable Native Client · · Score: 1

    Very annoying that chrome wont support 64 bit java. If you make 64 bit java the default on your computer, because say you want to run minecraft's latest server, then you can't run java in chrome cause it won't work and it uses the default path installed java.

  23. Re:recylcing objects for speed and memory savings on Linux Kernel Running In JavaScript Emulator With Graphics and Network Support · · Score: 1

    *clue needed

  24. recylcing objects for speed and memory savings on Linux Kernel Running In JavaScript Emulator With Graphics and Network Support · · Score: 2

    I'm puzzled how one makes it "fast". When my highly active programs run in a browser they tend to glitch and halt after a while if they have been doing lots and lots of quick object instantiation and destruction.

    You've almost figured it out!

    Recycle your objects. Enjoy instant performance improvements. (While this is not just true for JavaScript, it's obviously the advice you need.)

    Oh, and try learning the language. It's not like Java and C#. If you try to treat it that way, you'll end up writing crap. You can break yourself out of that easily enough by working through The Little Schemer in JS instead of Scheme.

    How one does that is not obvious to me. let's take an example. Suppose I create a function like this:

    var recylceObj = function( oldObj, newAttitributes) {
              for (var i in newAtritutes) {
                                oldObj[i] = newAttributes[i];
              };
    }

    var foo = recycleObj( oldObj, { x:1, y:2, z:3} );

    so superficially I just reused an old memory allocated object oldObj by overwriting it's attributes with new ones. But wait, to do that I had to instantiate the temporary hash { x:1, y:2, z:3} to transfer in those attributes. Which is memory allocation and object creation. It would in fact be simpler to write:

    var foo = { x:1, y:2, z:3};
    foo.prototype = oldObj.prototype;

    I would in fact think this latter way would be more efficient in both speed and memory. So How do I save anything by recylcing?

    is there a better way to recycle? what am I missing

  25. Re:is javascript faster than java? on Linux Kernel Running In JavaScript Emulator With Graphics and Network Support · · Score: 2

    I'm just learning javascript. I'm puzzled how one makes it "fast". When my highly active programs run in a browser they tend to glitch and halt after a while if they have been doing lots and lots of quick object instantiation and destruction. My guess was this was some memory leak or deferred garbage collection. I see inconsistent results across browsers.

    I'm enjoying learinging at how easy it makes doing graphics in a browser window. however It's a weird mishmash of incomplete grammars and high level commands. For example the lack of a class statement or a defined way to access a superclass is bewildering. It's even less complete that perl objects in many ways. Listing all the keys in a hash (associative array) gets conflated with all the other attributes of the hash, so there's weird kludges like "hasOwnProperty" that smack of being bandaid and afterthoughts. On the other hand it's got things like timed thread execution and some quite high level concept built in as primitives.

    What perplexes me the most is I haven't figured out how to debug it yet. I've been relying on a particular package called "processing.js" which has some very simple graphics. since processing.js acutally re-writes your javascript at run time, the messages in the browser console log are worthless. they don't even tell you the line number where the error occurs most of the time. The other debugging problem Ihave is that often the javascript one is writing only can work in the context of a web page (for example to play loaded sounds). so I don't see how one runs or debugs this outside of a browser. I don't get what the IDE's offer. I'm a noob so give me a clue not heckling please.

    Anyone have any advice on how to debug in java, especially when using processing.js.