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Comment: Bad dog! No biscuit! (Score 1) 46

I'm just waiting for drones that will simultaneously cut my lawn and deter burglars.

According to Gary Larson, that would be robodog Ginger featured in "You call that mowing the lawn? Bad dog! No biscuit!" Well, you might have to put a beanie prop-hat on the dog, but it would be pretty close...

Comment: Re:Too bad (Score 2) 66

To paraphrase, you can't be too rich, too thin, or have too many bits of precision in a calculation. With single precision you have to be enormously careful not to drop digits even in comparatively modest loops; with double precision you can many digits before you run out. You can see it in almost any computations involving trig and pi -- single precision pi degrades in series much faster than double precision pi. It isn't just a matter of not using forward recursion to evaluate bessel functions, which is unstable in any precision (or for that matter, using book definitions of e.g. spherical bessel functions in terms of trig functions) or reordering series to avoid subtracting big numbers and running small to big instead of big to small -- there is simply a big difference between cumulating a random walk with a random digit at the 16th place and one at the 8th place.

A second problem is the exponent. 10^38 just isn't "big" in a modern large scale computation. It is easy to overflow or underflow a single precision computation. 10^308 is a whole lot closer to big, even expressed in decibels. One can concentrate a lot more on writing simple code, and a lot less on handling exponent problems as they emerge.

A final problem is random numbers. This is actually a rather big problem, as lots of code (all Monte Carlo, for example) relies on a stream of algorithmically random numbers that (for example) do not have a period less than the duration of the computation and that do not have significant bunching on low dimensional hyperplanes or other occult correlations. It is much more difficult to build a good random number generator on fewer bits, because the periods of the discretized iterated maps scale (badly) with reduced numbers of bits and it is more difficult to find acceptable moduli for various classes of generators from the significantly smaller discretized space. You can watch this problem emerge quite trivially by building a Mandelbrot set generator in float and rubberbanding in -- oops, you hit bottom rather quickly! Rebuild it in double and you at least have to work to rubberband in to where it all goes flat. You have to build it in a dynamically rescaleable precision to rubberband in "indefinitely" as the details you wish to resolve eventually become smaller than any given finite precision. This actually illustrates the overall problem with single precision quite nicely -- the emergent flat patches in an graphical representation of an iterated map are isomorphic to the establishment of unintended correlations in long runs of iterated maps in a random number generator and the clipping of the graphical representation of small numbers illustrates the problems with mere underflow in real computations of interest.

Personally, I dream of default quad precision and 128 bit processors. 34 decimal digits of precision means that a random walk with n unit steps (which accumulates like \sqrt{n}) require (10^30)^2 = 10^60 steps to get to where I don't still have 4 significant digits. Even a rather large cluster running a rather long time would have a hard time generating 10^60 add operations. In contrast, with only (say) 8 decimal digits a mere 10^16 operations leaves you with no digits at all, assuming you haven't overflowed already. I've run computations with a lot more than this number of operations. I also like the idea of having overflow around 10^5000. It takes quite a while adding numbers at the overflow of double precision to hit overflow, and one basically could add overflow scale single precision floats forever and never reach it. That gives me comfort. It would also make writing a Mandelbrot set explorer tool where one would be likely to give up before rubber banding all the way to the "bottom" -- there are a whole lot of halvings of scale in there to play with that still leave you with much more resolution than needed on the screen.


Comment: Re:Do electrons vibrate? (Score 4, Informative) 27

by radtea (#49528149) Attached to: MIT's New Tabletop Particle Detector Sees Individual Electrons

Do electrons actually vibrate?


The electrons emit cyclotron radiation, because they are being accelerated by a magnetic field. The acceleration is always perpendicular to the electron's velocity vector, so they don't speed up, they just turn in a circle. However, all accelerating charges emit electromagnetic radiation, and in the case of an electron moving in a magnetic field in this fashion it is called "cyclotron radiation". In other contexts it is called "bremsstrahlung", and so on. Physicists often have multiple names for the same basic phenomenon manifesting itself in different circumstances.

Add "electrons vibrate" or "everything vibrates" to this account adds nothing and obscures the actual source of the radiation, which is continuity conditions on the electro-magnetic field. These conditions are described by Maxwell's Equations, which predict such radiation. There is exactly nothing in Maxwell's Equations that could be said to describe a "vibrating electron" in this context.

The summary is equivalent to an account of a baseball game written by someone who has never seen a ball, or a game, of any kind. It is depressing that "science journalism" scrapes along at a standard that is an order of magnitude below anything found in sports journalism, which is itself not exactly a paragon of insight and coherence.

The paper itself can be found here:

It is a beautiful piece of work that really does open up new doors to precision measurement of beta spectra.

Comment: Re:Baptists are already writing this week's sermon (Score 3, Insightful) 69

by radtea (#49517451) Attached to: 3.46-Billion-Year-Old 'Fossils' Were Not Created By Life Forms

The headline should really read 3.46-Billion-Year-Old 'Fossils' May Not Have Been Created By Life Forms.

And then apply the rule that "may" and "may not" have exactly the same literal meaning. Any headline that contains anything like "may" or "may not" is screaming sensationalism. "Scientists dispute oldest fossils" is informative, "Fossils may not have been created by life" is identical to "Fossils may have been created by life", and is therefore meaningless.

Comment: Re:The problem isn't intelligence - per se (Score 4, Interesting) 385

by radtea (#49500493) Attached to: Can High Intelligence Be a Burden Rather Than a Boon?

Intelligence in the intellectual, logical reasoning sense is a evolutionary epiphenomenon. It is only weakly selected for. We can tell this because its distribution in the population is so broad. There are no gazelles that run at half the speed of the fastest[*] but there is no shortage of people with IQs that are half the top and still manage to get along (putting "the top" at around 160 and "the bottom" around 80, which is the lower end of the "gets along OK in society most of the time" range.)

Logical, linear reasoning is a trick we've managed to train our bear to dance.

Some people happen to be really good at it. This can be a problem for them because so much of what humans do, and the accounts they give of it, make very little sense to the untutored mind.

We live in the Age of Bayes, and the Bayesian Revolution over the past thee hundred years (which takes in a lot of time before Bayes himself or the recognition that what we were doing is fundamentally Bayesian) has taught us some really important lessons about ourselves. Mostly how damned stupid we have been, even the highly intelligent. We've spent centuries arguing nonsense, from how three is equal to one for large values of three to the dharma of the tao.

In the past century or so we've been calling out the people who are most "intellectually gifted" and expecting them to solve our problems (in a past age it was the pious, or the people "of good family", etc). This has created a bind for them, because for most of that time we've also had no idea why people do what they do (spoiler: mate competition and selection play large roles, although we are still a long way from any kind of comprehensive understanding.)

There are also ethical constraints on what can be done to solve human problems. The utopian projects of the 20th century, despite their profound irrationality in so many respects, were manifestations of this belief that the human intellect had all the right tools for the job of reforming the planet. It didn't work, and that leaves us in the situation we are in today, where intellect is suspect as well as desired.

As such, it isn't necessarily a shock that people identified as "intellectually gifted" should feel less adequate after exemplary lives. Nor is it likely that's going to change any time soon, as we continue to look to the intellectually gifted to save us from ourselves, while steadfastly refusing to spend any time looking hard in a mirror for the source of most human problems.

[*] this may be false... feel free to fact-check me!

Comment: Re:What the fuck are you talking about? (Score 0, Offtopic) 385

by radtea (#49500413) Attached to: Can High Intelligence Be a Burden Rather Than a Boon?

Their high priests and emperors would cut the hearts out of living individuals, and then make those victims eat their own still-beating hearts before burning them.

Your slip into hyperbole here is not helping your case, which is otherwise pretty accurate.

The human heart is very well protected. Humans only have ten of fifteen seconds of consciousness without blood flow. Even granted they were using stone knives, which are insanely hard and sharp, cutting through the rib cage, severing the aorta, the vena cava and the pulmonary veins and arteries is not the work of ten or fifteen seconds.

It is also likely that the victims were too busy screaming to be properly said to eat anything.

So while the New World was in fact dominated by a blood cult that was carried out more formally in the politically organized areas, and it is not impossible that a few still-beating hearts were shoved into a few still-working mouths, the ritual of "feeding the victim their own heart" was a ritual, not a literal thing, and is best described as such.

You probably know all that, but the people who believe the myths about non-European cultures likely don't.

The blood cult was practiced all over the New World, much as the Norse Pantheon is recognizably related to the Sumerian one. Ideas travel. So even amongst the pre-political peoples of what is now Canada the practice of ritual torture, sacrifice and cannibalism was common, as was the denuding of entire landscapes for the sake of game.

The notion that North American native peoples lived in any kind of harmony with nature is simply false. We have overwhelming archeological and ethnographic evidence to the contrary, and anyone who believes otherwise is engaging in Creationist levels of evidence-denial.

Comment: Re:The third factor (Score 4, Interesting) 385

by radtea (#49500359) Attached to: Can High Intelligence Be a Burden Rather Than a Boon?

You've likely encountered this quote, but it bears repeating:

Nothing in the world can take the place of Persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan 'Press On' has solved and always will solve the problems of the human race. -- Calvin Coolidge, 30th president of US (1872 - 1933)

Comment: Mutant Great Whites... (Score 1) 193

...with laser beams! Radical!

Shades of a bad science fiction novel. Or even several bad science fiction novels.

Next up on the news at 9 -- replete from eating Fukashima, Godzilla shows up from the trenches off of Japan to eat the Independence before marching on San Francisco, plates a-glowing...

Comment: Perfectly understandable move... (Score 4, Informative) 208

by rgbatduke (#49495205) Attached to: Social Science Journal 'Bans' Use of p-values

...and this isn't even the first journal to do this. It's probably happening now because an entire book has just come out walking people how universally abused p-values are as statistical measures.


The book is nice in that it does give one replacements that are more robust and less likely to be meaningless, although nothing can substitute for having a clue about data dredging etc.


Comment: Re:Why stop at Scientology...? (Score 1) 700

by rgbatduke (#49492769) Attached to: 'We the People' Petition To Revoke Scientology's Tax Exempt Status

Donations are already taxed for most non-profits. Tax-exemption for donations isn't the same thing as not paying a corporate tax. Bear in mind that it is trivial to set up non-profit organizations and easy-peasy to use them to pass absolutely obscene not-profits straight through to the corporate officers as salaries, who just happen to be the folks that founded the not-for-profit and who own its not-for-profit shares that, in the event that those same officer/owners convert it over to for-profit, will become disgustingly valuable in an instant (see the history of Blue-Cross-Blue-Shield, for example). My wife worked for just such a non-profit until about a year ago. The company president of this not-for-profit company was knocking down seven digit salaries plus seven digit bonuses at the same time they were cutting her income to pay for an IT transition that they mandated. Her "donation" to the company was indeed not taxed -- it wasn't even voluntary. Non-profits need substantial tax revision almost as badly as religions.

You seem confused about the constitution, the bill of rights, and taxation in general, and nobody has suggested taxing people for exercising a civil liberty (certainly not me). What is being suggested is not giving people a tax deduction for money donated to a club. I'd oppose giving a tax deduction for dues paid to the Shriners, the Benevolent and Paternal Order of the Elks, the Masons, the Knights of Columbus, etc on the same basis, even though in some cases some of those organizations do some charitable works some of the time. I'm even borderline comfortable with tax breaks for donations to things like the Salvation Army whose primary focus is charity, although I am most unhappy with the way they pay their corporate officers and don't like the idea that those that they help get the help only at the cost of proselytizing. I could see clear to similar rules for genuine charities stripped of the missionary component set up by religious groups as well.

But the pass-the-hat donations to churches, used primarily to pay to maintain the infrastructure and personnel of the church, no. Taxing that isn't taxing your right to exercise a civil liberty -- nothing in the world is preventing you from belief or worship. It is taxing the money you are giving to a club designed to promote your belief in yourself and others and to support a huge formal infrastructure that yes, absolutely, exercises a substantial amount of power. We have similar laws regulating donations to things like political action committees and candidates for office -- if those laws were fairly applied to many churches they would not meet the criteria for 527 status because they often advocate for specific candidates or positions and are knee-deep in issue advocacy.

Some churches do good stuff some of the time. My niece is a Methodist minister; so was my grandfather. My grandfather, from all accounts, was a sharpster who ran his household until he ran out of money and then went and held a tent revival somewhere to refill his coffers. My niece works in Palestine trying to bring justice for the Palestinians and peace in a land that has almost never known it. But if you donate money to the Methodist church in church, almost all of that money goes to support the church itself and the minister that preaches to you on Sunday. That's the money I don't think should be deductible, because the government has no business subsidizing the support of churches, synagogues, mosques, temples, or the people that run them, "cult" or not, and tax breaks are a de-facto subsidy.

If at some time you want to talk about the religious beliefs or lack thereof of our founding fathers, I'm happy to direct you to their own writings in which it was made perfectly clear that most of them were anything from atheists to deists. Jefferson's personal ambition was to establish a state free from religion, not a religious state, a state where one did not have to profess belief in a God at all in order to exercise political rights.

If you look up above, you can see precisely where that plan has been run awry by your own words. You are quite right. Even for atheists like Abraham Lincoln and Jefferson and John Adams and George Washington and Thomas Paine, it was necessary to hide their (lack of) beliefs in a world where political power was solidly in the grasp of the churches. It still is. One cannot get elected as an atheist. Which all by itself says that something has gone very, very wrong with the founding fathers' ideal of religious freedom -- freedom from religion, especially in politics. All you are doing is confirming my reasons for wanting to oppose it -- you suggest that anybody "godless" must be "totalitarian" (bullshit!) or that simply actually enforcing the separation of church and state that the bill of rights requires and getting nonsense like "In God we Trust" off of our currency is somehow threatening to our civil liberties rather than actively enforcing them.

I really do suggest that you consider studying the Bible before you suggest that our rights were endowed by a Creator. The Bible makes it clear that humans have no rights whatsoever. For example, it explains that I can beat my slaves almost to death, or rape my neighbor's daughter as long as I pay her father 20 shekels of silver afterwards and marry her. Numbers 21 is another really excellent passage describing the genocidal slaughter of women, children and old men except for the young virgin women in the Midianite crowd who were given to the troops to rape and enslave as part of the booty -- by Moses, who was surely a righteous man, somebody Jesus was perfectly happy to walk around with up on the mount. Consider that at no time in the history of the world has God enforced a single human right. No injustice, no matter how it cries out to the sky for correction, has ever been repaired by a divine act. Every day acts of unspeakable horror occur -- plenty of them as the result of so-called acts of God -- without any hint of divine rescue or retribution.

No, human rights were invented by humans -- in particular by Thomas Hobbes, John Locke, and Thomas Jefferson, especially by Jefferson who gave them a compelling poetic appeal, one that could rouse passion in the human heart. The declaration of independence is a statement of what the world should have been if God had in fact been on the job, and an acknowledgement that since he's not, since there is no such thing, it is high time that we as human beings pick up the burden for ourselves. If you want heaven, if you want justice, you'd better put your shoulder to the wheel and make it happen here on Earth because there is no divine heaven or hell or cosmic justice before, during, or afterward.

I can do no better than close with a nice quote from Thomas Paine, one of our good old founding fathers:

All national institutions of churches, whether Jewish, Christian or Turkish, appear to me no other than human inventions, set up to terrify and enslave mankind, and monopolize power and profit.

That, my friend, is the common attitude of the founding fathers, most of whom were sufficiently adept at concealing the depth of their antipathy to organized religion that they could continue to hold political power in a world where mankind was already enslaved, where the church(es) already held the monopoly on profit and power. It has taken hundreds of years to break that monopoly. The work isn't finished yet. But the age of reason that Paine called for is gradually bringing it about, because -- and I know you won't like this, but it is simple truth and you should think about it -- reason and religion are fundamentally incompatible. You cannot consistently accept a dual standard for determining probable truth, one for "scientific" facts deduced using observation and consistently applied reason in the actual world and another for "truths" supposedly stated by people whose primary goal was the establishment of a stable religious hegemony that conferred upon them substantial power and wealth and tribal status, which have no observational basis and which cannot ever be verified or disproven by observation or reason.

That's why you are reduced to making up stuff about Creators and trying to tie it into what might have caused the Big Bang or other observed aspects of the visible Universe. Nobody can prove you wrong, to be sure. You could assert that the big bang was the hatching of a giant egg (Hindu), or the expression of certain bodily fluids (Greek) or that it can be mapped in some improbable way into the absurdities at the beginning of Genesis and nobody can possibly prove you wrong. In fact, you can make up a literally infinite number of stories for what might have gone on beforehand. You can support them by means of antique scriptures or just invent them. There really isn't any difference.

Physicists (I am a physicist, BTW) do the same thing -- they try to imagine what might have been going on beforehand. The difference is that their guesses and imagination are tempered by the need for absolute, rigorous consistency with the body of knowledge we have gradually built up that can be verified at any time by any person interested in doing so by the means of performing various experiments or observations, and that physicists do not assert their hypotheses as truth . Physical laws are expressed as probable truth -- in the case of some things, very, very probable truth -- but we always maintain the mental flexibility to change our minds in the event that an experiment comes along that disproves a belief or demonstrates that the belief is not complete.

Where is there any evidence of that rational process in religion? Physics is humble and skeptical where religion is arrogant and certain. In science there is no revealed truth, only truth as we can best discern it when we work very hard and in a completely open and collaborative way. In religion it is exactly the opposite -- all truth is revealed truth, and (with the exception of perhaps the Quakers) such truths are held to be immutable and unchallengable. For most of human history, to openly challenge a supposed revealed truth was to invite torture and death.

You like the idea of freedom. So do I. And the most basic freedom is the freedom to think, to challenge the system of beliefs you were force-fed as a child and indoctrinated in to the point where you find it difficult to challenge them. I suggest that you use it.


Comment: Re:Why stop at Scientology...? (Score 1) 700

by rgbatduke (#49487587) Attached to: 'We the People' Petition To Revoke Scientology's Tax Exempt Status

Not at all. I'm perfectly happy for people to believe anything they like. However, I absolutely object to giving them tax breaks on the basis of their belief system or to support an organized supernatural belief system. For one thing, as has been pointed out it clearly violates the separation of church and state (as do many other silly things, such as the references to God on currency, and yeah, I oppose those too because they do not speak for me or for a Hindu who believes in Gods, not (the Judeo-Christian) God, or for a Buddhist, or for many others. The state has no business even obliquely endorsing belief in the supernatural, especially given the lack of evidence for anything supernatural to sensibly believe in.

You clearly seem to have Obama on the brain, BTW. Curious, since this discussion isn't really about Obama -- it is a conservative principle to not force religious belief down people's throats and there was never any constitutional reason to give religions of any sort tax breaks (as I said, the Bill of Rights directly and specifically prohibits mixing church and state).

As for judging organizations about being a cult or not being a cult -- that's what is done NOW, when the Federal Government has to decide whether or not any given group of people who adhere to some absurd belief constitute a religion or a cult. The only rule that is consistently applied is that "old" absurd belief systems are grandfathered in and try to stomp on "new" absurd belief systems with hobnail boots, so anything new is a cult, anything old is a religion. So Jehovah's Witnesses, who were never anything but a cult and remain so today, are part of a religion in spite of the fact that some of their religious practices with their children actively endanger those childrens' lives. Ditto Mormanism. Ditto some of the other offshoots of Christianity with their tinhorn messiahs (there are a bunch of them out west and across the south). But Islam or Methodism or Catholicism aren't cults, because a lot of people believe in them instead of only a few. There's no more evidence for any world religion than any other -- zero equals zero -- but numbers apparently matter.

I disagree. I don't want to distinguish a religion from a cult at all. I want none of them to have any sort of legal protection or legal persecution, provided that they obey the common secular law, which includes taking care of your children and giving them blood-based products (like plasma or a blood transfusion) if they need them medically and so on. Including tax protection.

Look, if you wanted to join a chess club, you wouldn't try to deduct your dues. Why should you get to deduct your dues if you join a God club?


Testing can show the presense of bugs, but not their absence. -- Dijkstra