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Comment Re:please no (Score 1) 423

I heard that modern weather models have accuracy above 80%.

But weather is not climate, as we get reminded by Warmists every time there is a cold snap (they are mysteriously silent on this issue when there's a heat wave.)

Furthermore, predicting "the weather will be the same tomorrow as today" gets you about 70% accuracy (http://www.weatheranalytics.com/wa/weather-report-forecasts-improving-climate-gets-wilder/) so the increment to a shade over 80% at a cost of millions in hardware and enormous computational complexity is nothing to write home about.

Furthermore, this new report, if it withstands the test of time, is one more demonstration that anyone who says "the science is settled" is a political shill (likely for the far left: http://thebreakthrough.org/ind...)

Every few months we get an announcement of a new way in which climate models are wrong. For purely political reasons this is usually couched in terms of "worse" or "better" (usually worse, because that's what sells eyeballs) but to a scientist what matters is "correct" or "incorrect". The sign of the error is relatively uninteresting when evaluating the quality of the science.

And don't get me wrong: anthropogenic climate change is real and significant, and we should be aggressively pursuing changes. Carbon taxes, in particular, are an proven-effective policy that both reduce CO2 emissions and reduce income taxes and corporate taxes, so anyone who opposes them must be in favour of higher income taxes and corporate taxes.

And anyone who says both "ACC could result in the end of civilization" and "We should not be building new nuclear plants" is beyond evil. Nuclear power is a significant component of the climate change solution because it is the only generally-available, proven-effective replacement for base-load coal, and coal is a huge contributor to GHG emissions.

Comment Re:Stop. Posting. These. Articles. (Score 1) 99

It's interesting to people interested in such things

Those would be nerds, to whom this news matters.

The problem is not with the article, but the headline, which I agree is very misleading, although not as bad as those idiotic "Man does X using only HIS BRAIN"(and a few million dollars of heavy electronics that replace his arms and the keyboard.)

Quasi-particles are real particles. They are just composite particles that exist only inside atomic lattices instead of elementary particles that exist in free space. That someone has created a quasi-particle that is described by Majorana's equation is extremely interesting.

As well as the potential impact on climate change... no, wait, this discovery got "quantum computing" in the buzzword lottery... as well as the potential impact on quantum computing, this sort of discovery is interesting because it allows us to investigate the dynamics of Majorana particles empirically, and that can lead to unexpected and novel insights. Good science, that.

Comment Re:Why do people still care about C++ for kernel d (Score 3, Insightful) 365

C++ can't guarantee a binary API from one compiler to the next due to shitty non-standardized name mangling

IIRC from Stroustrup, non-standardized name mangling is considered a feature because it acts as a public interface for many other non-standardized incompatibilities under the hood. Without it, it would be possible to link code emitted from different C++ compilers that would fail to interoperate properly in subtle and difficult-to-debug ways.

So it isn't quite fair to imply that if only name mangling were standardized the problem would go away: it would really require a very large enhancement to the standard that would deal with all the different ways that compilers do things now. That potentially involves a vast amount of work on understanding current compiler technology, much of which would likely be obsolete by the time the standard shipped. Ergo: compiler compatibility is unlikely to ever happen.

I'm not saying this is a good thing, just that it's a thing. I currently code in C, C++ and Python, and C++ is by far the most difficult, dangerous and awkward of the three (or of any language I've ever coded in, really) but the additional power does make it worthwhile in certain circumstances.

Comment Re:Longterm use - tried out on humans ? (Score 2) 236

TFA says it has been used up to seven days in humans, so it's only a factor of ten or so to get a significant chuck of Mars transport out of the way.

In general, chemical reactions slow down with temperature, and while typical therapeutic hypothermia involves fairly high temperatures (~33 C) there may be room to reduce this considerably. Humans will never hibernate without a whole lot of physiological intervention, but it is far too early to say whether or not metabolic activity--including that of our commensal bacteria--can be reduced sufficiently to sustain a mission to Mars.

Comment Re:This sounds familar... (Score 4, Informative) 54

Is a quasi-moon like a quasi -planet (i.e., Pluto)?

Nope. Pluto's designation is based on it's size, mostly. The category "planet", like all categories, is made by humans to conveniently describe the universe to ourselves, and the precise boundaries are constrained (but not determined) by how the universe actually is and how we actually are. Within those constraints we can put the boundary where we like, and in the case of planets, smaller bodies that don't dominate their gravitational neighbourhood have been deemed to fall outside the human-created category we use the word "planet" to label.

Quasi-moons are bodies in solar orbits that have interacted with their quasi-primary such that they are "station keeping" with it. A body like this one will wander around in the general vicinity of Earth as both Earth and quasi-moon travel around the sun together. So from the perspective of an observer on Earth, the quasi-moon executes periodic but non-orbital motion: it wanders in a closed configuration that does not describe a path that goes around the Earth.

This is, like many such distinctions, fairly arbitrary: the sun's gravity at the orbit of the Moon is a good deal stronger than the Earth's gravity at the orbit of the Moon, so one could describe the Moon as being in orbit about the sun, with it's orbit perturbed into a wobble by the nearby Earth. That is, from an outside observer's perspective, the Moon's motion is never retrograde with respect to it's mutual orbit with Earth around the sun.

Consider the view:

O o .

where the O is the sun, the o is the Earth and the . is the Moon. In the configuration shown (with the Moon on the outer wobble of its orbit about the Sun) it is moving faster than average (imagine the Earth and Moon both rotation clockwise around the Sun, and the Moon moving clock-wise around the Earth, so when in the image above it is moving "down" on the page).

But in the situation that obtains two weeks later:

O . o

where the Moon on the inner wobble of its orbit about the Sun, it is still moving "down" on the page relative to the Sun even though it is moving "up" on the page from the perspective of an observer on Earth.

Another way to see this is to consider that the Moon executes a wobble like this once a month, traveling 2*pi*0.25 million miles (lunar orbit is about 250 thousand miles), but at the same time moves 2*pi*96/12 million miles in its orbit around the Sun (which is 96 million miles from Earth), and since 96/12 > 0.25 it should be clear that the Moon's orbital velocity around the Sun is higher than it's orbital velocity around the Earth. Ergo: no retrograde motion for the Moon!

All of this is a very long-winded way of saying: how we classify Moons vs quasi-moons is useful, but--as with all the ways we as knowing subjects classify the objectively real universe we live in--somewhat arbitrary. We could--but don't, so far as I know--have a name for the class of moon-like objects that have orbital velocities around their primary that are greater than their orbital velocity around their primary's primary (most Earth-orbiting satellites fall into this category.) Instead, we have a name for objects that don't execute motions relative to their (quasi-)primary that look like a loop around it from the perspective of an observer on the primary's surface.

Comment Re:the solution: (Score -1) 651

And that's all they've ever been - a feel-good measure that accomplishes nothing....

So they are the same as the 2nd Amendment, yes?

Let's be clear about this: widespread gun ownership in the US is held to be useful for two purposes:

1) empowering the people to overthrow a tyrannical government

2) personal protection.

The second of these is overwhelmingly what the gun lobby focuses on when selling guns to their "patriotic American" base.

The problem is: widespread firearms ownership is demonstrably, empirically, a terrible solution to the problem of personal protection. Firearms for personal protection--specifically handguns--are vastly more widespread in the US than in any other developed nation. The murder rate in the US is vastly higher than any other developed nation.

So anyone looking at the data would have to say that widespread handgun ownership is "a feel-good measure that accomplishes nothing". Anything else would be simply bizarre, a complete rejection of the data. (http://en.wikipedia.org/wiki/List_of_countries_by_firearm-related_death_rate).

Please note: I am not arguing that the 2nd Amendment doesn't protect American's right to keep and bear arms, including handguns, AR-15s, etc. I am arguing--pointing out, really--that a very significant proportion of advertising, promotion and rhetoric around gun ownership in the US is aimed at exactly the kind of feel-good emotionalism that gun owners frequently complain about with regard to people who promote solutions to the problem of personal protection that have actually worked everywhere else in the developed world.

The 2nd Amendment and other features of the uniquely broken American political system prevents those solutions--gun control and the rule of law--from being applied in the US, but to pretend that is anything other than a tragedy that is indirectly responsible for the deaths of thousands of innocents every year is laughable.

Better solutions than guns exist to the problem of personal protection. Only in America are those solutions incapable of being implemented.

Comment Re:They will move to a different charging model (Score 3) 488

If the amount of money made from the actual electricity falls too far then the cost will be transferred to a network connection costs.

It doesn't really matter how the accounting is done, utilities are going to have to charge more for power as they sell less of it, because their fixed costs are such a large proportion of their total costs. Fixed costs account for anywhere from 75 to 100% of plant costs: http://www.eia.gov/forecasts/c... (the data in table 1 appear to mean "fuel cost" when they say "variable cost").

The utilities model is based on the notion that you can recover your capital costs (and more) over the lifetime of the plant. The rapid rise of solar in particular is putting that at risk, and utilities are caught between a rock and a hard place. They can fight by keeping power costs low, and lose, or they can fight by raising their power costs--however they want to do the accounting--and also lose.

Personally, I hope they raise the costs. It will make low-carbon alternatives like wind and solar more attractive.

Comment Headline: "Force of nature gave life its asymmetry (Score 4, Interesting) 120

Article:

The interaction of left-handed electrons with organic molecules is not the only potential explanation for the chiral asymmetry of life.. Meierhenrich favours an alternative â" the circularly polarized light that is produced by the scattering of light in the atmosphere and in neutron stars3. In 2011, Meierhenrich and colleages showed4 that such light could transfer its handedness to amino acids.

But even demonstrating how a common physical phenomenon would have favoured left-handed amino acids over right-handed ones would not tell us that this was how life evolved, adds Laurence Barron, a chemist at the University of Glasgow, UK. âoeThere are no clinchers. We may never know.â

The new work is interesting and important, but its primary significance is that it makes future work distinguishing the possible alternatives more challenging. It's also interesting because unlike the other two proposed mechanisms it is a result of the fundamental asymmetry in the weak force rather than an accidental boundary condition, so it implies that life everywhere is more likely than not to be right-handed, whereas the explanations involving magnetic fields will make a universe that's 50/50 right/left.

Comment Re:"could be worse than Heartbleed" (Score 2) 318

The NIST page indicates that DHCP could be used to exploit it.

Any program that a) listens on a socket and b) calls out to a shell with an argument partially constructed from user input is vulnerable if the shell is unpatched bash. Apparently DHCP does this: https://www.trustedsec.com/sep...

The only saving grace in this bug is that it's relatively easy to patch on client and server machines.

But there are a lot of things that aren't client and server machines that run linux and use bash. Routers, cable modems... all kinds of embedded systems. These things generally lag behind everything else. Firewalls will no-doubt be getting upgraded as we speak, but routers? Ultrasound machines in hospitals?

There is a lot of hard-to-patch hardware out there, and while I'm sure manufacturers are working on getting fixes out, it's going to be a long, hard, expensive process to ensure they're implemented.

We're incredibly fortunate that this bug is pretty easily fixable, but there may well be additional lurking issues, and there is always the chance we are going to find something that can't be easily fixed without breaking existing bash functionality. The probability of that is low, but the consequences would be enormously bad.

We've all heard the saying, "If builders built buildings the way programmers wrote programs the first woodpecker to come along would destroy civilization." This has given us a glimpse of what a woodpecker might look like.

Comment Re:We care why? (Score 5, Insightful) 50

One would assume that it's a safe bet it's common in most other systems as well...

I guess if one was ignorant of the past 300 years of science one might do that. Otherwise, it would be too obviously stupid, as it would require believing something trivially and completely false: that what we assume is particularly likely to be true.

Why not just assume the sun moves around the Earth? It's obvious, isn't it?

In the present case, there is a whole bunch of stuff to be interested in.

1) There is always the possibility that the chemical environment or formation process of the Earth or solar system was anomalous in some way. For example, it has us in it, and as near as we can tell intelligence of the specifically human, universally representational, machine-building kind is fairly rare (there is no evidence for it elsewhere.) So given that, it is not implausible that there are other weird things about our solar system, and we should likely be cautious about assuming that other planetary systems are much like ours. The astonishing discovery of hot Jupiters, for example, is an instance where we were looking for something that we were almost certain didn't exist (simply because it was the only place our current instruments were sensitive) and found something, quite unexpectedly.

2) Even given that water is common (which we don't know until we've measured it) there is the possibility that it is almost always sequestered in dense, cloudy atmospheres, or in icy outer planets, or cometary halos, etc.

3) Even given that clear atmospheres exist (which we didn't know until these guys measured it) we don't know what their typical composition is (and we still don't, based on a population of one.)

4) Even given that clear atmospheres have water (which we now know) we are most interested in finding Earth-like planets, which means a clear atmosphere with water and oxygen (which is a key signature for life as we know it). Testing out various detection ideas and proving they work is a huge step forward even if the first planet they found has a hydrogen atmosphere.

So there, just off the top of my head, are a few reasons. Assumptions don't produce knowledge, which is why we shouldn't give them much credence. Observations do produce knowledge, which is why we should be excited about a new mode of observation finally bearing fruit.

Comment Re:Clouds (Score 2, Informative) 50

Assuming the cloud is water droplets and not methane or whatever.)

Clouds or other forms of haze can be made of all kinds of things, and we observe this in our solar system, so there is no reason to assume clouds or haze in exoplanet atmospheres are water vapour.

Remember, all we know is we can't get decent absorption spectra from them, so assuming anything about them would be saying, "We can't see anything, so we know it's water."

That's like saying, "I know that's a Muslim woman because they are completely covered and I can't see their face" (there have been many cases of men, mostly criminals and not always Muslim, wearing similar clothing because people seemed tuned up to make precisely this error of "I can't see it, so what I can't see must be X".)

Comment Re:The simple fact that we can't talk about this.. (Score 1, Insightful) 207

This is far too politicized to be judged scientifically anymore.

The problem is that Warmists have politicized the science almost from the word "go". You can tell this because prominent political organizations like Greenpeace say on the one hand that climate change could be a civilization-ending event, and on the other hand we must not ever even think about using nuclear power to solve it, even though nuclear is the only proven, sustainable, economic and practical alternative to coal (this is even more true since the Japanese demonstrated practical extraction of uranium from sea water.)

Greenpeace says the only acceptable solutions to the problem of ACC are reduced consumption, de-industrialization, and various command-economy initiatives of a kind that would represent a massive expansion of government control. This is not surprising, because Greenpeace is a far-left political organization with no interest in the environment whatsoever (it was founded as a science-based organization, but changed to politics after a few years when some of its leaders recognized that politics was a lot more lucrative.)

So having made "the solution equal to the problem" in the public discourse, Leftist political organizations are now upset that Rightwingnutjobs are denying there is a problem. The rightwingers aren't responding to the science, they are responding to the Left's insistence that if there is a problem, it only has far-left solutions. That's obviously stupid (what the Righties are doing) but hardly surprising. Politics has always been a game of power and opposition, and the Right is taking the role of opposition in this case.

Me, I care primarily about the science, and defending the integrity of science from both sides. I acknowledge ACC is a problem, and I've arranged my life so my carbon footprint is tiny. I work at home in a mild climate, don't drive, almost never fly, etc. I support carbon taxes because the data show pretty clearly they work and have some nice side benefits, like reducing CO2 emissions. By "they work" of course I mean "they work to reduce income taxes and corporate taxes", which surely anyone who isn't some socialist nut-job would be in support of. But I also support the development of nuclear power and research into geo-engineering, because it would be utterly evil to believe we are risking the end of industrial civilization and not be open to all possible solutions.

But because the issue has been politicized since the '80's, I get accused of being a Denialist by Warmist nutjobs. It isn't enough that I agree a) there is a problem and b) support some economically defensible solutions. I have to quack the mantra of "the science is settled" (which it isn't and never can be) and "97% of climate scientists agree!" (which they don't and it's irrelevant) or I'm the enemy.

If Warmists cared about science, they would discuss the science, and reasonable policy alternatives. Instead, they rally people against pipelines and oppose nuclear power and complain that the science has become politicized, to which I say: they have only themselves to blame.

Comment Re:Most rational people never believe in AGW (Score 4, Informative) 207

The winds are just moving the heat around a bit.

"Moving heat around a bit" has a tremendous impact on global climate. This is why ENSO in the south Pacific is so important: by moving heat around it changes global circulation patterns, which changes the overall energy balance of the Earth. This is why the simple achievement of getting reasonable agreement that anthropogenic CO2 is adding about 1.6 W/m^2 to the Earth's heat budget is such a huge scientific achievement, and while that conclusion is still subject to significant uncertainty: because adding heat changes the winds and currents which themselves influence the radiative balance. There are even (very unlikely) models in which adding sufficient heat causes global cooling due to increased transport of energy to the poles, where it radiates back into space more efficiently.

Climate is a non-linear, strongly coupled system. Treating it as if one could draw simple conclusions dismisses the complexity and difficulty of climate modelling. It also results in underestimating the uncertainties in models.

Any competent computational physicist (me, for example, but other people a lot smarter than me as well: http://online.wsj.com/articles...) will tell you that climate models are far less certain than their public, political proponents are claiming. This does not mean that "global warming is a hoax" or any such Denialist gibberish. It means that models are uncertain, and we should not get bowled over when they are subject to correction, even significant correction.

In the meantime, we can do some pretty universally agreeable things, like shift income and corporate taxes toward carbon taxes. After all, income and corporate taxes apply to something that is basically good--making butt-loads of money--while carbon taxes apply to something basically bad: burning irreplaceable fossil fuels and dumping garbage into the atmosphere. I guess anti-capitalist crusaders might oppose carbon taxes, but I can't think of any other reason to do so. If anyone is really in favour of keeping income and corporate taxes high, do feel free to make your case, though.

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