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Comment Magnetism = relativistic electricity? (Score 4, Interesting) 67

Question for any physicists in the audience: I have long heard that magnetic forces can be described as relativistic effects of classical electricity (here, for instance). How do magnetic monopoles fit into this? Are they are purely quantum mechanics/QFT concept, or is there some way to describe them classically that makes it clear why so many people are expecting to find them?

Comment Correlations (Score 1) 103

I'm no statistician, but I ran quick-and-dirty linear correlations on the rankings from the MIT site with Excel (shut up; I'm at work). Oddly, the strongest correlation was a negative one between Safer and Depressing -- stronger even than Wealthier/Safer. Here are my results, if anyone's curious. (Some repeated for readability.)

Wealthy/Boring: -.32
Wealthy/Depressing: -.79
Wealthy/Livelier: .49
Wealthy/Safer: .79

Safer/Wealthier: .79
Safer/Boring: -.15
Safer/Depressing: -.84
Safer/Livelier: .24

Livelier/Wealthier: .49
Livelier/Boring: -.61
Livelier/Depressing: -.22
Livelier/Safer: .24

Depressing/Wealthier: -.79
Depressing/Boring: .27
Depressing/Livelier: -.22
Depressing/Safer: -.84

Maybe an actual statistician can tell us something more interesting.

Comment Was there another movie? (Score 4, Informative) 1029

And sooner than he may have thought, the implosion has arrived: in the past couple weeks, six wannabe blockbusters have cratered at the North American box office: 'R.I.P.D.,' 'After Earth,' 'White House Down,' 'Pacific Rim,' and 'The Lone Ranger.'

That's only five movies, not six. Was that number a typo, or did you leave a movie out?

Comment Re:Learn OpenCL (Score 4, Informative) 198

Or when hardware engineers design chips, do they actually model out the components of every single transistor?

Chip design is absurdly complicated (even on the digital side), and involves several layers of abstraction. In roughly increasing level of detail:

* Spec level: high-level behavioral description of the functionality of a digital system, something like "8-bit 115.2kbps UART" or "2MHz PWM with 0-100% duty cycle in 0.1% increments".
* HDL/RTL level: software-like description of the complete system design. Can range from higher-level (describing behavior) to lower-level (describing specific logic). When people talk about buying, selling, or creating "IP" in the chip design world, they're usually talking about RTL for a single functional unit.
* Gate level: Logic gates and flip-flops and their connections.
* Transistor level: The transistors that make up the gates, and their connections.
* Device level: The behavior of an individual transistor.
* Physical layout: Just what it sounds like; the actual arrangements of metal and silicon.

There are some more in between, but that should give you an idea. HDLs are not necessarily low-level. For large designs (like modern SoCs), it takes some *very* expensive and complex software to go deeper into the list, and the process is not entirely automated. So I wouldn't say hardware design can't be high-level. The difference is that in hardware, you always have to care about the lowest level when you're doing your high-level design, while in software you can take more things for granted. So even though a board-level design might just be a bunch of off-the-shelf chips hooked together, it still takes a lot of work to make sure everything comes out right.

Comment Re:Not just NYC (Score 1) 382

You do know that weather alerts and amber alerts can be turned off, but not alerts sent out by the President of the United States [fcc.gov], right?

That's because wireless alerts are descended from systems intended to warn the public about an incoming nuclear attack. ICBMs take less than 30 minutes to hit their target (much less for nearby sub-launched missiles), so the warnings were set up to interrupt every TV channel and radio station immediately. The civil defense functionality has never been used, and it probably won't be anytime soon.

Comment Ambiguous pronunciation (Score 1) 478

I searched for Houston, TX and got drums.spark.rarely, which brings up the problem of ambiguous pronunciation -- is it drum.spark.rarely, drums.park.rarely, or drums.spark.rarely? They might need to add some more filters. Maybe check for homonyms too.

I like the idea of a shorthand for global coordinates. There are places where this could be really useful. Aren't there streets in Tokyo (and London?) with no names? Now everybody in the world has an easy-to-write* address. It would also be useful for meet-ups. A three meter square is a lot less ambiguous than a street address. And while there's no simple distance/direction calculation, there is some built-in error checking -- if you get the wrong word you'll probably get a location a long way off (c.f. lat/long typos, which can give any size error in any direction).

It would be neat if there were a way to algorithmically generate place names from GPS coordinates and get a similar scheme, but that seems unlikely.

Comment Re:Getters and setters (Score 4, Interesting) 543

Tangential question: What's the advantage of having getters and setters vs. just accessing the variable directly? If automatically generating getters and setters is just an easy/common thing, what function do they really serve?

I've only done OO programming in college (I do embedded C now), so I'm assuming there's some real-world advantage that I'm not aware of.

Comment Re:You're testing wrong (Score 2) 177

The real issue with USB keyboards is that if multiple keys are pressed within one polling interval, the order is ignored. For fast typists, this can easily result in swapped letters. It's quite annoying. Unfortunately, this behavior is part of the HID spec so there's not much that can be done now.

To the submitter: I'm very sensitive to input lag, but I've never had noticeable lag from any PS2 keyboard. Right now I'm using a Dell AT101W, and before that I had some junky IBM membrane thing. Do you have any software installed for e.g. multimedia keys on the keyboard? That's the only thing I could see causing a problem unless the keyboard itself is just bad. Not sure I'd trust reaction time sites, though -- that's a pretty coarse measurement. If it's just for gaming, I wouldn't worry about the keyboard. The hand-eye coordination for the mouse is where you really need the tight feedback. It's a rare game that responds that quickly to the keyboard to begin with.

If you're really dedicated to low-latency keypresses, I'd suggest a PS/2 keyboard using laptop-style scissor switches, if any exist. Another option would be Cherry MX Blue keyswitches, which activate closer to the top of the stroke. There's some hysteresis, though, so if you're jamming on the same key in a game it's easier to miss a stroke.

I went crazy looking for a keyboard several years ago, and ended up a connoisseur. Definitely my most boring interest. :-)

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