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Comment Scientists failed us? (Score 4, Insightful) 495

Oreskes argues that scientists failed us, and in a very particular way [...]

What the bloody fuck? Scientists failed us?

Not short-sighted politicians, not lobbyists for climate-raping corporations, not greedy corporate types.

No, of course the Scientists failed us. They didn't warn us strongly enough!!!

Okay, breathe.

Getting over the initial outrage, note that to have an actual effect on modern day policies, Oreskes could have written that the politicians were to blame. If modern-day people are shown that they will be remembered in infamy, it might just cause them to change. It happens with presidents all the time - doing something to be remembered by, leaving a positive mark for future historians, &c.

Comment Comment from an AI researcher (Score 4, Interesting) 583

I've been working on strong AI for the past 7 years. Here's my take on the whole issue:

Military person: We want your software/techniques for an autonomous war machine.

Me: Uh... that's a really, really bad idea. You'll make mistakes, and then...

Military person: We know what we're doing, son.

Government - any government - won't see the problems until it's too late. To take obvious examples from history, government never thought that land mines would pose any sort of problem for future generations, and never thought that randomly bombing terrorist organizations would increase their number.

Having just finished "Harry Potter and the Methods of Rationality", there's a concept in that book "never reveal the secrets of power to someone who's not intelligent enough to figure them out for themselves", as applied to - for example - the atomic bomb. Einstein and others regretted ever unleashing that level of destructive power on humanity, not for any reason other than it would be misused by short-sighted people. It held promise for a utopian easing of the worlds troubles, while at the same time made it easy to obliterate a city on a whim.

For example Leó Szilárd (IIRC - I may be remembering the wrong name) discovered that graphite can be used as a neutron moderator thus making chain reactions possible. Had he not published his results, the atomic bomb might have been delayed by decades - possibly indefinitely.

I've discovered a few things that might be "results" in strong AI. I dunno if I want to publish, though(*) - the idea of a house-cleaning drone seems pleasant enough, but reading about a sentient tank going berserk in Afghanistan and wiping out a small village puts me to pause.

"No one's to blame, it was a software glitch. We've patched and fixed all the other units."

(*) Moral advice on this issue would be appreciated.

Comment Re:Better solutions (Score 3, Informative) 46

Are there any issues with silicon solar cells that make them (protected against visible light, obviously) unsuitable? Compared to power silicon or anything for computation you can get enormous area for relatively little money.

Huh. I hadn't thought of that. A quick google search shows that solar cells can be used as radiation detectors, and they generally have large capture areas. I'll have to try this out.

This looks like a good background document for detecting radiation using semiconductors.

This is the type of amplifier you need as a 1st stage in your detector, should you want to build your own. (Google "Charge Amplifier" for more info.)

The radiation comes in as quick pulses (3 us or so in my circuits), so normal incident light shouldn't interfere with the detection. You could perhaps get both power and detection from the same cell.

I've been interested in detecting not only the radiation, but the direction it came from. A 3-d array of detectors with an incidence/correlation circuit can give a general idea of the direction of the source, relative to the detector. I haven't done this yet due to the complexity and expense of the detectors, but solar cells being cheap and easily available I might just try this out. Hmmm...

Thanks for the suggestion.

Comment Better solutions (Score 5, Informative) 46

I've been building geiger counters as a hobby for the past couple of years. I was consulting with some people in Japan right after Fukishima helping to build reliable detectors.

Geiger Muller tubes require a specific "plateau" of voltage to get consistent results. Too low and you're not picking up much radiation, too high and you get spurious results and can burn out the tube. The correct voltage varies with individual tubes.

This isn't normally a problem, except that there's a glut of surplus Russian geiger tubes on the market right now with unknown provenance and unknown parameters. Unless you calibrate each tube to find the plateau voltage, and unless you calibrate the resulting counter with a known source, the data you get will have no predictive value.

It's straightforward for a hobbyist to put together a project using one of these tubes and get it to click in the presence of radiation, and this makes a fine project for electronics learning, but you have to take further steps to get a reliable instrument. No one ever does this. The circuits I've seen have an unregulated high-voltage proportional to the battery voltage - it gets lower over time as the battery runs down. The voltage is chosen from the tube spec sheet, instead of determining the correct voltage for the tube. Circuits have design flaws such as using zener diodes for regulation, but not allowing enough current through the diode for proper function. And so on.

I've seen lots of these hobbyist projects in the past few years, especially since Fukishima. They're fine projects and well-intentioned, but generally not of any practical use.

Does radiation detection(with actual accuracy, linearity, and repeatability, not just a quick demonstration that you can add some noise to a webcam by pointing a small sealed source at it) have currently good, or at least promising for the not too distant future, solid state options?

Virtually any semiconductor will detect radiation. What you want is a semiconductor with a large capture aperture(*), which is the area through which the radiation passes. A 2n2222 transistor will detect radiation quite well, but it's capture area is tiny and won't see much of the radiation (saw the top off of a metal-can version and use a charge amplifier).

Power transistors such as the 2n3055 have large silicon dies and therefore larger apertures - as much as a square centimeter - but this is also quite small for capture.

The modern equivalent is to use a big diode such as a PIN diode. These can be quite large, but also expensive for the hobbyist.

A GM tube has a capture area which is the cross sectional area of the tube. These can be made quite large; and as a result can be made quite sensitive to the amount of radiation flux in the area. Hobbyists can also make their own tubes with enormous capture areas - it's not very difficult.

Large diodes are available for detecting radiation, but a GM tube is simple and can be easily made with a very large capture aperture. Also, GM tube their capture efficiency (the percent of radiation that gets in which is is actually detected) can be higher than the diode solution.

(*) There's capture aperture and detection efficiency. GM tubes have an efficiency of about 10%, meaning that only 10% of the radiation that gets into the tube is detected. Diodes have similar efficiencies, depending on the photon energy and thickness of the silicon die.

Comment Re:The Cult Leader will solve the problem! (Score 4, Insightful) 124

I'm sure the world's most average Ob/Gyn [Ron Paul] - and most successful living American cult leader - is also a highly qualified expert on Ebola.

That sounds suspiciously like an ad-hominem argument. "Most average" Ob/Gyn? What does that even mean, other than to convey dark undertones?

Shouldn't we be debating the things he says? Shouldn't we be considering the merits of his argument, rather than his background?

Obama's Ebola czar (Ron Klain) is a lawyer and former chief-of-staff. Do you think *he's* qualified to tell us what we're doing wrong?

What the heck are you getting at? What's your purpose in posting this? Is there some way in which you gain by posting such drivel?

You're right about being modded down - your post does nothing to inform the discussion.

Comment Unnecessary and ineffective travel restrictions? (Score 2) 478

Frieden and other officials say such a move would be counterproductive, citing lessons learned from the SARS outbreak a decade ago. "The SARS outbreak cost the world more than $40 billion, but it wasn't to control the outbreak," says Frieden. "Those were costs from unnecessary and ineffective travel restrictions and trade changes that could have been avoided."

Unnecessary and ineffective travel restrictions? Have these guys been to an airport recently?

The government doesn't give squat about unnecessary and ineffective policies. It will be decades before we can get back to reasonable airport security. A waste and burden on all Americans, helping to keep the economy down (viz. international tourism) with no end in sight.

If the government believes that people will feel safer with more restrictions, then that's what will happen. Hell, even if that weren't the case the government will still do it because they can say that it's to keep people safer.

This will just be another excuse for draconian policies. Trading more freedoms for more safety, because "safety at any cost" lets them reform the nation.

Comment Quick explanation (Score 5, Informative) 99

A Majorana particle is it's own antiparticle; such as, for example, a photon.

Most fermions have different antiparticles from themselves: Protons are notably different from anti-protons, electrons are different from positrons, and so on. The one exception is the neutrino, for which the question is not yet settled.

If the neutrino is its own antiparticle, we should see double-beta-decay events. A beta decay emits a neutrino, so if two happen simultaneously the neutrinos should annihilate if they are their own antiparticle. (Wikipedia link)

As yet no experiment has seen double-beta-decay, so it's likely that the neutrino has a distinct anti-neutrino - an intriguing prospect.

The article referenced in the post does not identify the fermion involved, so one can only assume that it's a "quasi particle", which is a type of vibration. Essentially a phonon (sound wave) with fermion-like properties.

Comment Guns are not the problem (Score 1) 651

Would you be in favor of gun control if it made your children less safe?

The studies and statistics about guns have been so completely obfuscated by special interests that it's nigh impossible for an average citizen - even smart ones like Slashdot readers - to answer the simple question: "is free access to guns good or bad?".

Looking into this in depth is really hard, but when you go back to basics there's a glimmer of truth.

Firstly, the thing to measure is mortality rate. Not all gun incidents lead to death, and if you have no money for medicine (or food) because you were robbed at gunpoint, it affects your chance of death.

Secondly, socialized medicine has such an enormous impact on mortality that you can't simply compare American mortality with, for example, the UK. You could compare UK mortality with, say, Swiss, or you could compare areas within the US which allow/disallow free access to guns. New Hampshire versus Michigan, for example.

When you do the proper comparison, you find that easy access to guns lowers the mortality rate.

This is counter intuitive simply due to the badly-cited statistics. Yes, if you let your kids play in the front yard of a gun owner their chance of death by accidental shooting goes up; however, their chance of death by all causes drops precipitously. You can believe the chosen statistic and it's unspoken implication, or you can dig into the real issues.

I'll leave you with this recent paper which attempts to sort out the issues in an academically rigorous manner. Here's a quote from that paper:

On the one hand, despite constant and substantially increasing gun ownership, the United States saw progressive and dramatic reductions in criminal violence in the 1990s. On the other hand, the same time period in the United Kingdom saw a constant and dramatic increase in violent crime to which England’s response was evermore drastic gun control including, eventually, banning and confiscating all handguns and many types of long guns.

[...] To conserve the resources of the inundated criminal justice system, English police no longer investigate burglary and “minor assaults. As of 2006, if the police catch a mugger, robber, or burglar, or other “minor” criminal in the act, the policy is to release them with a warning rather than to arrest and prosecute them.

I'm happy to discuss the advisability of gun control with anyone, so long as they don't cite a misleading statistic out of context, or focus on the wrong issues.

I like to form my opinions based on science. If you know of convincing counter studies, I'd like to read them.

Comment Thanks for the threat (Score 1) 115

nice gesture, but the reason this is inadequate may be summed up with the monkey-water-spray experiment.
http://www.answers.com/Q/Did_t...

Did I mention that it's anonymous? No lists, no donations, no polls, no canvassing. Just resolve to vote against all incumbents when you're in the voting booth.

Thanks for the threat, but I think everyone here realizes that voting in the US is safe.

Join the boot party: anonymous and safe!

Comment Churn the pot (Score 1) 115

ask yourself: which candidate will sell us out and cave to the surveillance state?

answer: both. the fix is in.

happy voting! now move along.

I don't live in California, but I'm voting against anyone currently in office.

Keep churning the pot. Eventually, they'll become pro-public just to stay in office.

Comment Should we vote out the incumbents? (Score 5, Interesting) 126

Overwhelming response telling our leaders exactly what we wanted through our only feedback system. And it is blatently IGNORED in favor of paid interests. It's not a surprise, considering that the FCC leader is ex-cable, and they are appointees directly from big business. However it obviously shows just how badly this country is broken. I'm not an alarmist, but it this simply isn't going to change with the current US government system. They have no REASON to change it.

Would you consider voting out the incumbents?

It's the only voting strategy that can make a difference, the only one that matters.

When congressmen realize that they can be voted out after a single term, we'll have pro-public policies.

And the best part is it's completely anonymous! No registration, no donations, no E-mail lists, no paper trail. Just resolve that "if this doesn't go in favor of the people, I'm voting against the incumbents".

Join the boot party - give 'em the boot!

(P.S. - Pass this along)

Comment Isn't that enough? (Score 1) 288

I know everyone is all over Uber and and the other one because the cars are "nicer" and the service "better" than cabs. But [...]

Um... isn't that enough?

Firstly, you're wrong about the liability.

Secondly, you are confusing the possibility of injury with its probability.

If the probability of injury is small and the cost of injury is also appreciably small, the expected cost of using Lyft or Uber may be much less than the expected cost of using a cab.

For an example, if a ride-share is $6 less than a cab fare, and if there is an average of 1 injury every 100,000 rides, then if the average injury costs less than $600,000 then it's a better deal for everyone to use the ride share.

Using this reference, cabs crash about once every 300,000 miles.

Also note, the number of crashes in regular driving has decreased dramatically over the last few years, probably due to increased safety measures in vehicles and modern roadway improvements (Denver Barriers around bridge supports, for example).

And in any event, most people have health insurance. At the very least, a significant portion of riders would have health insurance - enough to reduce the risk by a further factor of four or more.

SHELL GAME is where you can't win. CASINO GAME is where the odds are against you. Uber and Lyft seem to be decidedly in the passenger's favor.

Cue the irrational fearmongering reply: "unless you are the one injured, then how would you feel!".

Comment Have we lost judicial oversight? (Score 3, Interesting) 288

Apropos of nothing, when did we allow unelected regulators complete authority over the law?

It seems that every regulator now has the authority to declare something illegal, judge that an infraction has occurred, assess fines, and force collection.

If someone is in violation of a regulation, shouldn't the regulator present their evidence before a judge? Don't we want an unbiased 3rd party to chime in on whether the law is clear, whether the evidence merits a violation, and whether there are extenuating circumstances?

The policy of default judgement by fiat, with a "go to court to reverse it if you think you've been wronged" is a recipe for injustice and corruption.

When did we lose judicial oversight of our regulations? Did it happen slowly, or was it a sudden change?

Comment Science at its best (Score 1) 291

The debate on this issue is far from over, and it'll take years to sort out all the contradictory evidence.

Once again, science is reduced to debate and belief. Medicine is rife with these sorts of "schools of thought"(*), it's almost as bad as economics. This is not the "more refined theory supplants approximate theory" that one finds in, for example, physics. It's "yeah, this looks good and makes sense, so we're 'gonna go with it" science.

This is what allows vested interests to decry science in favor of their own agenda. Who is the average person supposed to trust when scientists keep making and overturning bad conclusions, in the face of authority figures pushing their own agenda?

All I see here, in this forum, is appeal to the difficulty of experimentation. If the original single experiment is so hard or expensive to reproduce, should we be basing our conclusions on the single experiment?

Scientists need to kick it up a notch.

(*) As a typical example (dozens more are easy to find), Helicobacter pylori was identified as the source of gastric ulcers, yet the medical community didn't believe the results for many years. The amount of suffering and loss that occurred while this "school of thought" was slowly overturned is incalculable.

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