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Comment Re:Worry about your own country (Score 1) 751

By the same argument, shouldn't Trump stick to what he knows? Such as preserving a huge inheritance, real estate development, managing beauty contests, replacing trophy wives, and clever tax evasion strategies?

The argument for Trump is that his success in his chosen fields, real estate development and building a personal "brand", qualifies him for the many disparate things required of a president. Why doesn't the same argument apply to Hawking? Despite extreme physical disabilities, he's a financial and scientific success with a powerful personal "brand." You have not provided any reason to value Hawking's political opinions less than Trump's.

Comment Re:So? (Score 1) 751

If in the future Stephen Hawking has his science proven wrong is he then considered ignorant? Isaac Newton was proven wrong, he was ignorant. Did anyone prove Trump wrong? Or is it just opinion that doesn't have scientific merit?

Isaac Newton was so close to "right" that we still use Newton's equations instead of Einstein's 100 years after Einstein proved Newton wrong. Hawking is probably "wrong" in a similar way.

OTOH, Trump has proved himself wrong each time he has contradicted himself. If someone emits a pair of contradictory statements, then one of the pair must be false, and in most of Trump's cases, there's no room for "so close to right." So how often has Trump emitted contradictory pairs? See this list. I know you may disagree with the politics of the source, but if Trump made those statements, then Trump is wrong - in a big way - hundreds of times.

Comment Re:Yes. (Score 1) 143

Because shorter wavelengths of light are preferentially scattered off the molecules in the earth's atmosphere (that's also why the sunset is orange - - when a light ray (low angled at sunset) passes thru enough atmosphere, most of the blue and green get scattered away). Why does light scatter that way? Because the molecules are much smaller than the wavelengths involved, but the closer the size ratio, the bigger the interaction. Why? There's probably some confusing equation in electrodynamics that explains it based on Maxwell's equations, but it's not a very satisfying explanation. And if it is satisfying, the "Why are Maxwell's equations true" question will probably be a stumper. Or the why after that. I don't think you can actually get to the bottom of the "why" questions.

Comment Re:Google Legal Fund (Score 1) 343

> and then to turn around and sell the details of your life for even more money.

Not exactly. Google's ad model depends on them knowing a whole lot more about your life than anyone else. They don't sell the details of your life, they sell access to you based on their superior knowledge the details of your life, If they sold the details, their knowledge wouldn't be very superior for very long, would it? That's why it actually behooves Google to keep your details secret from their customers and only sell access.

Comment Re:Implications for Centos & Scientific Linux (Score 2) 76

Scientific Linux 6.0 thru 6.6 also use kernel 2.6.32. I'm seeing kernel-2.6.32-573.12.1.el6.x86_64.rpm dated 15-Dec-2015 as the newest SL6 kernel, The Upstream Vendor says they'll be supporting EL6 for 10 or 11 years, so roughly until 2020. Perhaps they'll be backporting changes from newer kernels to 2.6.32?

Comment Re:Yeah, um, not so much (Score 0) 819

Gosh, I'd love to find the link and read the whole context of your Daniel Webster quote. I tried to googled it, and my meager search skills were unable to locate the source.

And, given the stuff Webster has written elsewhere about the public health approach, see http://annals.org/article.aspx... this quote doesn't really sound like Webster...

Comment wonder if it's a big LITTLE architecture? (Score 1) 136

From what I've read about AMD's Zen architecture, they've dispensed with the "two single threaded cores per module" architecture and now have SMT allowing two threads in each core according to this, much like "hyper threading" on Intel chips.

If that's the case, and we can expect a 32 core chip to execute 64 threads, then that's an awful lot of threads to keep supplied with data and instructions. In comparison, the biggest Intel Xeon I know about, the E5-2699 v3 has 18 cores, 36 threads, 45MB of last level cache, and 4 memory channels (68GB/sec to RAM). Intel sticks pretty close to that 1.25MB cache per core in their big Xeons. So if you adhered to Intel's apparent rules, a 32 core 64 thread chip would need 80MB of LLC and maybe 6 memory channels. Anandtech estimates 5.7 billion transistors for the big Xeon. Scaling the Intel design from 18 to 32 cores would require over 10 billion transistors! That number leads me to believe that an SMT 32 core 64 thread chip built with 2016 technology would not be practical.

What might be practical is a chip with some "heavy" cores optimized for balls-to-the-wall floating point execution, and other "lighter" cores for lower power integer tasks. This has been done in "octocore" mobile phone chips and called a big LITTLE architecture. The idea is that the OS and various decoding and checksumming tasks can stay resident on the low power light cores, while the heavy cores do things like game physics and photo noise reduction. Because the multiprocessing is not symmetric, the OS kernel needs special rules to assign tasks to cores. Which leads me to wonder if AMD has something like big LITTLE up its sleeve for 32 core Zens.

Comment Re:Dumbing Down (Score 5, Informative) 54

"it could begin the next instruction while still computing the current one, as long as the current one wasn't required by the next " Doesn't this go without saying?

Back in the day, pipelining - issuing, say, a new multiply instruction every clock, even though several earlier multiplies were still working their way thru the pipeline - was too expensive for most architectures. An instruction might take multiple clock cycles to execute, but in most architectures the multi-clock instruction would tie up the functional unit until the computation was done - you might be able to issue a new multiply every 10 clocks or something. Pipelining takes more gates and more design because you don't want one slow stage to determine the clock rate of the whole design.

Which leads us to the early RISC computers, I can recall an early Sun SPARC architecture that lacked a hardware integer multiply instruction. The idea at the time was every instruction should take one clock, and any instruction that demanded too long a clock should be unrolled in software. So this version of SPARC used shifts and adds to do a multiply. At the time, that was a pure RISC design. One of the key insights in RISC, still useful today, is to separate main memory access from other computations.

The CPU design course I took in the late 80's said Seymour Cray invented that idea of separating loads and stores from computation, because even then, even with static RAM as main memory, accessing main memory was slower than accessing registers. So by separating loading from RAM into registers and storing from registers into RAM, the compiler could pre-schedule loads and stores such that they would not stall functional units. Cray also invented pipelining, another key feature in most modern CPUs (I'm not sure when ARM adopted pipelining, but i'm pretty sure it's in some ARM architectures have it now). Of course Cray had vector registers and the consequent vector SIMD hardware.

I don't think Cray invented out of order execution, but I don't think he needed it; in Cray architectures, it would be the compiler's job to order instructions to prevent stalls. In CISC architectures, OOO is mostly a trick for preventing stalls without the compiler needing to worry about it (also, with many models and versions of the Intel instruction architecture out there, it would be painful to have to compile differently for each and every model). So, for example, the load part of an instruction could be scheduled early enough that the data would be in a register by the time the rest of the instruction needed it.

Anyway, the upshot is modern CPU designs have a bigger debt to Cray than to any other single design.

Comment Re:What happened = gambling + sports (Score 2) 95

Any time gambling gets mixed with sports you have a mechanism where cheating can get you money. Whether it's the 1919 Chicago "Black Sox" or one of these point shavers gambling always has the potential to lead to sports cheating.

... Which makes you wonder why the US professional leagues have invested their own money in fantasy sports gambling sites.

Comment How about if we OWN our personal information? (Score 5, Interesting) 79

Imagine if we owned our personal information as a form of intellectual property? Big corporations have gotten pretty good at protecting their intellectual property rights. Maybe it's time for us ordinary folks to own our personal information. Then we could license it to companies for particular uses, but they wouldn't have the right to sell it without our permission.

Comment Re:Does not crash Chrome on my Win7 laptop (Score 1) 205

It does not crash the copy of Chrome running on my Win7 machine. I let the machine automatically update when it feels like it; the machine is currently running Chrome 45.0.2454.93

When I paste http: //a/%%30%30 into the address bar, I seem to get a web search for 30 30, with the first two hits being .30-30 Winchester - Wikipedia & 30/30 Poetry. I get the exact same behavior pasting into the search box. So it seems the current default behavior is to treat a malformed URL as a text search.

P.S. This meme should be a bonanza for the good folks at 30/30 poetry!

Comment Re:Don't take yours in. (Score 1) 411

Diesels are better at CO and unburnt hydrocarbons, because they always take in a full charge of air, no matter how small an amount of fuel is being injected (therefore combustion is more complete). They may be marginally better at CO2, but that is mostly because they tend to be under powered compared to "performance cars".

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