June 2011 – Spinor Info

Facebook

Jun 292011

Looks like Facebook is having trouble grabbing my blog entries. It stopped a while ago… when I reset the blog settings on Facebook, it downloaded the latest, but then it stopped again.

I’ll try to reset it one more time but if it doesn’t work… hey, blogs were meant to be write-only anyway. I am yelling at the world, I don’t necessarily expect the world (or even my close circle of friends) to yell back.

Still, one would think that Facebook, with its fancy, shiny new data center and all that, would be a little more robust.

Kaku again

Environment, Physics, Technology No Responses »

Jun 292011

The headline on CNN tonight reads, “An American Fukushima?” The topic: the possibility of wildfires reaching the nuclear laboratories at Los Alamos. The guest? Why, it’s Michio Kaku again!

What I first yelled in exasperation, I shall not repeat here, because I don’t want my blog to be blacklisted for obscenity. Besides… I am still using Kaku’s superb Quantum Field Theory, one of the best textbooks on the topic, so I still have some residual respect for him. But the way he is prostituting himself on television, hyping and sensationalizing nuclear accidents… or non-accidents, as the case might be… It is simply disgusting.

Dr. Kaku, in the unlikely case my blog entry catches your attention, here’s some food for thought. The number of people who died in Japan’s once-in-a-millennium megaquake and subsequent tsunami: tens of thousands. The number of people who died as a result of the Fukushima meltdowns: ZERO. Thank you for your attention.

Yelena Bonner

History, Politics, Society No Responses »

Jun 212011

Yelena Bonner is dead. May she rest in peace.

Headshot

Health, Politics No Responses »

Jun 122011

Gabrielle Giffords is on the mend. It is inspiring. I’d not wish what she had to go through even on my worst enemy. I hope it’s not just morbid curiosity on my part when I wonder, to what extent will she be able to recover in the end? Is her personality, are her mental abilities intact? I hope so, but there are limits to what medical science can do when a lead slug rips through a large chunk of your brain.

Combine harvesters and GPS

Communication, Politics, Technology No Responses »

Jun 092011

John Deere, a manufacturer of agricultural machinery, would not be the first company to come to mind when I think about a controversial issue related to the Global Positioning System… but in retrospect, it makes perfect sense. Large, automated farming operations rely heavily on precision (augmented) GPS.

And according to John Deere, it’s precisely those kinds of users who would be most heavily affected by the wireless data network proposed by a company named Lightsquared, permissions for which were mysteriously fast-tracked by the FCC in the United States last fall. Yes, it smelled fishy… On the other hand, the United States is not some corrupt third-world country and I was somewhat skeptical about the dramatic claims of interference. Weren’t radio devices, including GPS receivers, supposed to be equipped with sufficient frequency filters to ensure no interference from neighboring frequency bands, no matter what? Is it really valid to assume that just because a neighboring frequency band is reserved for mobile satellite applications, all transmissions in that band will be low power? Well, John Deere’s material answers my questions in full, and it seems that the concerns are valid, more valid even than initially thought. I wonder how the FCC will respond.

Enigma

Programming, Science No Responses »

Jun 072011

One of the things I like the least about New Scientist (which, in many respects, is probably the best popular science magazine out there) is the “Enigma” brainteaser. I am sure it appeals to the “oh I am ever so smart!” Mensa member crowd out there but…

Well, the thing is, I never liked brainteasers. Are you really smarter than someone else because you happen to remember a random historical factoid? Does it really make sense to ask you to complete a series like, say, 1, 4, 9, 16, ? when the answer can be anything, as there is no compelling reason other than psychology (!) for it to be a homogeneous quadratic series?

But then… sometimes brainteasers reveal more about the person solving them than about the solution itself. I remember when I was in the second or third grade, our teacher gave us a simple exercise: add all the numbers from 1 to 100. (Yes, this is the same exercise given to a young Gauss.) Like Gauss, one of my classmates discovered (or perhaps knew already) that you can add 1+100 = 101; 2+99 = 101, 3+98 = 101, and so on, all the way up to 50 + 51 = 101; and 50 times 101 is 5050, which is the correct answer.

Trouble is, my classmate didn’t finish first. I did. I just added the darn numbers.

Between quick and smart, who wins? What if you’re so quick, you don’t need to be smart? Is it still smart to waste brainpower to come up with a “clever” solution?

Last week’s New Scientist Enigma puzzle caught my attention because it reminded me of this childhood memory. It took me roughly a minute to solve it. Perhaps there is a cleverer way to do it, but why waste all that brainpower when I can do this instead:

/* New Scientist Enigma number 1647 */

#include <stdio.h>

int main(int argc, char *argv[])
{
    int d1, d2, d3, d4, d5, d6, n;

    for (d1 = 1; d1 <= 9; d1++)
        for (d2 = 1; d2 <= 9; d2++) if (d2 != d1)
            for (d3 = 1; d3 <= 9; d3++) if (d3 != d1 && d3 != d2)
                for (d4 = 1; d4 <= 9; d4++)
                    if (d4 != d1 && d4 != d2 && d4 != d3)
                        for (d5 = 1; d5 <= 9; d5++)
                            if (d5 != d1 && d5 != d2 && d5 != d3 && d5 != d4)
                                for (d6 = 1; d6 <= 9; d6++)
                                    if (d6 != d1 && d6 != d2 && d6 != d3 &&
                                        d6 != d4 && d6 != d5)
    {
        n = 100000 * d1 + 10000 * d2 + 1000 * d3 + 100 * d4 + 10 * d5 + d6;

        if (n % 19 != 17) continue;
        if (n % 17 != 13) continue;
        if (n % 13 != 11) continue;
        if (n % 11 != 7) continue;
        if (n % d4 != d3) continue;
        printf("ENIGMA = %d\n", n);
    }

    return 0;
}

Yes, I am quick with C. Does that make me smart?

New calculators

Calculators No Responses »

Jun 052011

Years ago, just about every visit to a thrift store yielded a new and interesting addition to my little museum of programmable calculators. Not anymore… the ones still missing are unsurprisingly the ones that are quite hard to find, and in any case, truly vintage calculators are becoming ever more scarce. (I suspect it has to do both with their age and the fact that far too many people discovered eBay.) So it came as a pleasant surprise that the other day (when I made a sad final visit to the veterinary hospital for Tarka’s remains) I found not one, but two vintage calculators in a thrift store along the way. True, they’re not programmables, just ordinary “four-bangers” but they’re certainly vintage alright: a somewhat unusual red LED Lloyd’s brand calculator and a first-generation “yellow LCD” model from Sharp.

Vigilant cats

Cats, Personal No Responses »

Jun 042011

I am an atheist. To the best of my knowledge, there is no such thing as heaven, not even kitty heaven. That means that when a cat dies, it is truly dead.

That does not stop me from imagining, though, that in a sense, our two cats Marzipan and Tarka are still with us, perhaps watching our house while we sleep, as these cats do in a wonderful New Yorker cartoon titled Vigil:

The lady doth protest too much, methinks

Computer Security, Politics No Responses »

Jun 022011

Although the Chinese are protesting loudly, too loudly perhaps, I have no reason to question the credibility of Google’s claim that recent attacks targeted at high-profile Gmail accounts were, in fact, coming from China. As a matter of fact, I can confirm from my own experience that a clear majority of automated ‘bot attacks intercepted by my server originate from Chinese IP addresses (here is a recent small sample of 14 attempts: 5 came from China, 2 from the US, 1 each from Japan, Bulgaria, Thailand, Ecuador, Poland, Singapore and Brazil; a previous data set of 15 attempts included 6 from China and 1 from Hong Kong). Which is why I thought it was high time for the Pentagon to declare publicly that hacking can constitute an act of war.

Cell phones

Health, Technology No Responses »

Jun 022011

After all the hype and insanity, it is reassuring finally to hear a lone voice of sanity in the debate, reignited by the WHO’s idiotic report, about cell phones and cancer.

OK, maybe “idiotic” is too strong a word… how about “irresponsible”? Everything is “possibly carcinogenic” of course. For instance, all cancer cells contain a significant amount of a chemical known as oxygen dihydride. This evil chemical can kill in many different ways, cancer is just one of them… it can also cause asphyxiation.

But back to cell phones. Unlike X-rays or UV, low frequency electromagnetic radiation does not cause chemical changes. The heat generated as a result of brain tissue absorbing a fraction of the phone’s transmitted power (a few hundred mW at most) is minuscule, a tiny fraction of the heat generated by the brain itself as it operates. Furthermore, we are routinely exposed to much stronger low-frequency EM fields generated by things like the electrical wiring in our houses, electric motors, CRT televisions, overhead power lines, other radio transmitters… or, for that matter, heat from a stove, which is also electromagnetic radiation, surprise, surprise (but of course “radiation” sounds a lot scarier than “heat” or “waves”). There is no convincing mechanism, no conclusive evidence either, and plenty of well-established reasons to believe that these cell phone concerns are pure nonsense… so how can a body like the WHO scare people like this? It is reprehensible.