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Comment With a club in one hand... (Score 1) 278

... of course. Because if you have to explain it at all to anyone over the age of five, nothing less than a clearing blow to the head will work. One hard enough to clear that head of most of the superstitious brain matter that resides within it.

I say this with a rather enormous amount of experience on the subject. Absolutely no scientific or rational or empirical argument will convince someone that their religious beliefs are wrong. The entire sub-field of cognitive dissonance in behavioral psychology is devoted to understanding why this is so and how to deal with it, but its empirical conclusions are that a human deep in the throes of CD is not going to be pulled out of it by a silly little thing like facts, not even the blatant in-your-face failure of the core belief. There is even evidence that the more absurd the belief and the more humiliating its failure the stronger the denial becomes, the more powerful the state of CD itself becomes.

So don't bother pissing into a category four hurricane, my friend. Radiometric dating will not work. Astrophysical observation will not work. Paleontological observation of the orthogonality of human and dinosaur fossils will not work. Attacks on the core scriptural mythology (showing that it is absurd and self-contradictory and filled with evil and not in agreement with known geography or facts) will not work. Arithmetic (for example, showing the absurdity of a 5-6 inch per minute world-spanning rain that lasted 40 days -- the rate and time required to cover Mount Everest -- while preserving several million species in a handmade wooden boat the size of a Wal-Mart with no air conditioning nor heating nor ventilation for an additional half a year) will not work. Nothing works. If mere rationality or evidence worked, it would already have done so.

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Comment Re:Pointing out the truth can not be bigotry... (Score 2) 1121

Had he expressed hatred or prejudice based on their religion, like the AC above did with Islam...

Fuck Christianity. The only thing it has going for it is that it's not quite as evil as Islam.

...that would be bigotry.
You know... picking A religion as being "more evil" based on current political situation, when every single flavor of Abrahamic religion has uncountable crimes to answer for, and those others aren't much different either.

Pointing out that all brands of Christianity are the same fairytale (only told a bit differently) is just telling the truth.

Just like pointing out that all religions are evil as they teach the people to build their view of reality based on a delusion - basically, inducing billions with cognitive dissonance bordering on insanity.

Meanwhile, staying politically correct and letting them carry on with their delusion without at least pointing out the most glaring flaws in it - that would be hypocrisy.
Also, infliction of harm through inaction.

Sadly, this is deeply insightful and correct. I do think it is possible to sort religions and sects out very roughly in order of the overt evilness of their scriptural precepts and functional memes, but it is much more difficult to project this evil onto individuals who nominally belong to such a sect. That is because we live in an age of heresy unheard of before, where everybody feels perfectly free to makes stuff up and alter the fundamental scriptural precepts and memes at will. Hence if you point out (correctly) that the position of most Southern Baptist churches is that homosexuality is a sin:

http://en.wikipedia.org/wiki/Homosexuality_and_Baptist_churches

then of course somebody will turn around and point out an exception. And since we outlawed burning people, hanging people, torturing people, jailing people, silencing people, persecuting people, prosecuting people, and otherwise using force majeure and mortal sanction to enforce rules against choice, there have been plenty of exceptions, in fact being heretical is the post-Enlightenment post-Protestant normal, with an ever increasing divergence of belief. So although it is absolutely true that the official position of the Catholic church is one that opposes the use of birth control, in the US nearly all Catholics would be considered heretic by the non-heretical standards of Catholicism 400 years ago, and most sexually active Catholics use birth control. One can also compare Bellarmine's Letter to Galileo (which lays out its formal dogma concerning the ad literam interpretation of scripture and the horrific doors of heresy and contradiction that are opened by allowing it to be "interpreted" according to the discoveries of the science Galileo and others were in the process of inventing) to modern reality, and note that all of those predictions have, in fact, come to pass.

The point in the end is that none of this matters. One can take any of the scripture-based religions and note countless contradictions in their scriptures and that will not falsify them in the minds of individuals who nominally subscribe to it (but then lay on a small mountain of individual heresies according to their individual whim) because they will, as you note, willfully engage in a rich mixture of the practices associated with cognitive dissonance to avoid confronting the contradictions. Hermeneutics, exegesis, head in the sand syndrome, or simple denial, one cannot prove them wrong and hence they consider themselves "free" to continue to believe an absurd mythology (modified to suite their particular personality).

And this will still not make that mythology true! Or make it probably true, the only kind of truth a good Bayesian can acknowledge. Lack of evidence is not evidence of lack, perhaps, but it also damn well isn't evidence for, and the default state of belief, the null hypothesis, is disbelief in any given exotic proposition concerning the metaphysical nature of the real world. Any other system leads, as you note, to a kind of mass delusion, to the evil of willfully believing the untrue. How can one choose wisely, especially when confronted with ethical choices, on the basis of (probably) untrue beliefs with no objective support?

One of the many great lies concerning religion is that religion is harmless. Believing in things that aren't true causes countless life decisions to be made poorly at best. Even Buddhism suffers from this problem -- it is based on a model of serial reincarnation and some sort of automated cosmic justice engine that is all pure fantasy, without a shred of objective, double blind verifiable support (and with no POSSIBLE model for how the cosmic/karmic justice engine might actually work, or how any possible part of our "identity" might be preserved at the information theoretic level to bounce around from physical matrix to physical matrix). One of the consequences of this false idea is that Buddhism considers it a virtue for lay people to support the "clergy", people who have given up participating in ordinary life in favor of meditating and seeking enlightenment. In principle if you help somebody become enlightened in this life, you will have a better chance of enlightenment yourself in the next one.

Notice how even this very simple, seemingly harmless assumption leads to great evil. If, in fact, we have exactly one lifetime in which to attain "enlightenment" ourselves, working hard and giving our money to a slothful drone so that they can be enlightened in our place makes zero sense, it is in fact precisely the sort of abuse Buddha railed against in the prevalent Hindu priesthood, that routinely extorted a living from the peasantry. That doesn't make the other precepts of Buddhism (which are practical and empirical) wrong, it just means that there should never be a separate "lay" community and "monk" community with the former supporting the latter in any way. Quakers got this one right, where of course they get OTHER things wrong.

A rational being separates rational ethics from myth-based morality, and does not base entire systems of asserted "right action" on unverifiable post-mortem hypotheses born of some mix of imagination and con-artist greed way back in the most ignorant and brutal of times. In the end, that's what almost all of the world religions actually are.

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Comment But sadly, no alligators... (Score 3, Interesting) 398

... in Durham, in spite of the fact that alligator reproduction is an excellent bellwether and they are abundant a mere 150 miles away due East on the coast. 1 degree is 70 miles North, 4 to 6 is (say) 350, so by now there should be alligators in Virginia on the coast and central NC where I live FROM the coast. Alligators can only reproduce when a winter is frost free, as temperature determines the gender of the alligators in the egg. First and last frost in Durham haven't discernibly changed in the forty years I've lived here, starting back in the last "the Ice Age is starting" panic in the early 70s. There have been some bitterly cold winters and some remarkably warm ones -- much like the winters over all of the last century. We've set 100 year records for snowfall in the last 13 years, had a snow and ice storm on the Outer Banks (and inland) where it never seems to snow in mid-April, and had a killing frost in May, three full weeks after our supposed last-frost date. We've had winters where the Bradford Pears and Redbuds started to bloom in mid February (easily a month early), where it hasn't snowed at all, when you could sunbathe in mid-January, at least if you picked your days.

This winter was amazingly normal. A handful of small snowfalls, a few warm days, but mostly cold, often wet and cold, with lots of frost. The Bradford Pears and Redbuds still haven't bloomed, although we've had a few days of really nice spring-like weather (quite seasonal) and it didn't frost last night although it did the night before. The massive snows of winter all fell to the west or to the north, never quite reaching us here (except as cold nasty rain a few degrees above freezing -- got a lot of that).

There's plenty of scientific evidence of warming, as long as you pick your days, pick your events, pick your years, pick your starting points, and don't look at all the evidence that contradicts it. As everybody knows, scientific studies prove that green jelly beans cause Acne.

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Comment Re:One small problem (Score 4, Informative) 368

But what about all those reactors that blew up or melted (in TFA)? Or were they cheating and just bombarding the nickel with slow neutrons? One would think that if they produced an exothermic reaction even one time and weren't complete Pons and Fleishman nutcases they'd be able to pick up the beta (if not gamma) signature of the events. I'm also a bit curious as to just where the energy produced "comes out". They assert that no gamma rays happen. They get electron and neutrino out. Presumably we're talking about order of MeV/event, so the reaction produces order of MeV electrons (we hope, as energy going into neutrinos is gone forever) and a certain amount of lattice recoil in the now-copper nucleus. MeV electrons seem to have enough energy to produce an electron-positron cascade and convert at least some of the energy into X-rays (ionizing radiation). Probably relatively easily stopped (as is the beta itself) but the process would likely not be "radiation free". Finally, those same electrons seem as though they have the right general range of energy to be captured by the hydrogen nuclei (or would, if they didn't scatter on the way in and if there was any sort of cross-section) leaving open the possibility that the electrons themselves would create the requisite electron excitation and some sort of chain reaction might be possible.

Interesting idea, in other words, but TFA doesn't clarify the underlying physics to the point where it is really intelligible.

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Comment Re:Nice thing about red dwarf stars (Score 3, Informative) 132

A tidally locked planet would have all of its atmosphere period precipitated out on the dark side. There would be no habitable band. The antipode opposite the sun would be open to space, cooling the surface there, essentially 100% of the time. There would be no factors driving global circulation -- the atmosphere would rapidly stratify (and get very hot indeed, stably, on the side facing the sun). Eventually, where by eventually I mean in a matter of a few days if one stopped the Earth from rotating without vaporizing it (can't be done, sure, I know) it get cold enough to first rain, then snow, the snow carbon dioxide, then the greenhouse effect disappears and the temperature really plummets, and in just a little bit more time you have a rain of oxygen and nitrogen followed (as they deplete the atmosphere by a fall of solid oxygen-nitrogen sleet). As fast as it falls out on the dark side, it is replenished from the warm side (cooling as it comes) until the warm side -- now bloody hot not unlike the lit side of the moon -- has almost no atmosphere at all. The dark side has a rather large mountain of frozen air centered fairly symmetrically on the solar antipode. There would probably be some residual partial pressure of gas, but it wouldn't be enough to keep your blood from boiling anywhere on the planet's surface.

If the atmosphere was a more exotic mix, you'd actually precipitate out the gases in layers, frozen methane in one layer, oxygen in another, hydrogen and helium on top of the whole mess at the end.

So "tidally locked" is indeed a fatal problem.

Comment Re:And of course ... (Score 2) 240

All this being said, any kind of intellectual property law is a farce against the nature of any truly free market because it violates real property rights. It essentially posits that I cannot use my materials to make things I want to make because somebody else "owns" the "idea" of using materials that way. No government should be able to tell somebody that they cannot make things with their own property, or configure their property in some way that another lays claim to. Either you own something (physically!) and have control over its disposition or you don't. The whole concept of "intellectual property" should be excised from society.

Good luck with books, movies, and so on, then. It takes millions to make a good movie. Once digitized, it takes zero dollars (not really, but a number asymptotically approaching zero) to make and distribute one billion copies of it. If I have to right to use my own materials (my computer) to make anything I want (a copy of the movie) and sell it (although god knows what I'm selling, a pattern of electrical energy that happens to have meaning and hence value?) without restriction, then there will be no more movies that are more creative than stupid pet tricks or youtube. There will be no more books -- as an author, I can tell you that it takes an enormous amount of hard work to write a book, and to write it with no possibility of reward makes it too big a waste of time (and requires one to have a day job to support it, leaving one with even less time). There will be an enormous impoverishment in music, in art, in literature, in film, in theater -- even the author of a play needs to make money or it isn't worth it to write plays.

Good luck with drugs, too. It requires order of a billion dollars to develop a new drug and bring it to market. Once that is done, of course, the synthesis chain is known and anybody can make it for a fraction of the development cost. Companies take huge risks now developing drugs and without some protected period to make back their investment and a sufficient profit before companies with no actual investment at all in the development can make the product and undersell them we won't see any more new drugs. It won't be worth it. One can go right on down the line with inventions of all sorts. Inventing them is one thing, investing money in bringing them to market another, but once they are proven it is invariably trivial to clone them at a fraction of the development cost and with none of the risk.

The problem with patent and copyright IP laws isn't that they aren't valuable and necessary. It is that they have long gone from protecting the legitimate right of the inventor author to make a protected profit from the time and money they risked creating something new that benefits everybody to protecting the "rights" of an entire legion of bloodsucking parasites that have attached themselves to every aspect of delivery of that benefit to the consumer and who want their right to the protected profit stream to exist independent of the original purpose, that is, the reward of the original creators and risk takers.

We already have the concept of taxation of things "at risk" in a way that is differentiated from riskless taxation in corporate investment. We need to apply this same concept to copyright and patent protection, and issue it in such a way that it only applies as long as the original risk takers are receiving some predefined fraction of the income, and then only for a finite period of time.

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Comment Re:And of course ... (Score 3, Insightful) 240

I thought that the government was, by definition, the group who has the biggest gun, for as long as that state lasts. So there is no in between.

Life in the state of nature is ugly, nasty, brutish and short, and we all live in a state of nature at all times. All aspects of the social contract are our attempt to collectively minimize our risks and maximize our advantages and benefits, generally by ganging up on would-be bullies or out-group folks. Historically, this has been a lot easier to accomplish with memetic support structures like the illusion of human rights, religious duties and obligations, the fear of a supernatural deity with the biggest gun that one could ever conceive of (but one that is only used after you are dead), and government bureaucracy. Traditions, too.

In the end, patent rights and copy rights are what "we" say they are, collectively, and can enforce by the direct threat of and delivery of violence on members of the herd that disagree. "We" generally establish these illusory rights according to some mushy but reasonable principles such as rewarding the inventor and/or author (so that they will continue to produce inventions and stories and so on -- it is in our own self-interest to keep them motivated). However, a much smaller set of "we" also benefit tremendously from the delivery systems for the inventions, books, music, art and so on created by the talented few but enjoyed by the greedy many. Those delivery systems have long since been co-opted as the true basis for patent and copyright law, more the latter than the former. Patents at least have a reasonable lifetime, but a copyright now is damn near forever, long past the actual lifetime of an author.

The corporate interests of the world would, I'm certain, like to turn patents and copyrights into property forever, with no time out. That way they become pure commodities that can be bought and sold indefinitely. Imagine a world where the rights to Shakespeare's plays were still for sale, traded like pork bellies or mattresses. Imagine a world where you have to pay somebody every time you read, see, or hear one of Shakespeare's plays, where even media copies are sold per use, not as things you can own. That's the ideal of the publishing industry, with the ideal of the manufacturing sector and drug industry regarding patents close behind.

This leaves the problem of enforcement, the big guns. Any law that is ignored as universally as the copyright laws are currently ignored is no law. They are unenforceable, and everybody hates them. The illusion that they are somehow necessary in order to reward the actual creators of IP, carefully fostered by the media industry, is finally breaking down as well. At some point in the evolution of the digital Universe we will probably find some way of directly rewarding the authors of books, creators of music, inventors of fabulous machines only but in a way that strips away the guarantee of huge profits for the (largely unnecessary) middlemen. But to get there, we have to pry congress away from the clutches of the large, wealthy, and loud lobbying groups that advocate for the protection of their "rights" to charge the moral equivalent of a toll for going down a public road.

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Comment Re:Wait, what? (Score 2) 379

I used Perl-Tk for mine -- SDL wasn't around yet IIRC, nor was Gtk, and I was porting an interface I originally wrote in Tcl/Tk once I realized that Tcl was insanely out of sync with the way I think and code. In the end it worked perfectly, but it was a bit of a mess to write. Not an exercise I'm eager to repeat (and I long since learned to code in C/Gtk for the same kind of application), but I still have the source squirrelled away in case I ever need to recycle it in some way. But the amazing thing about a dancing bear isn't how gracefully it dances but that it dances at all. A >>simple Tk interface in perl was, and probably still is, a piece of cake and you have all of that string parsing power just sitting there at your beck and call.

Games, though -- wow! But then, as one of the top posters noted perl is relatively efficient as scripting languages go, sometimes within an order of magnitude of compiled code. Hard to do much better than that with any of the languages that do dynamical allocation of all variables as you use them, creating everything as complex opaque hashes behind the scene just so you can address a[34] without defining or allocating a or even assigning values or referencing a[0] to a[33] (where I'm deliberately leaving off the $ -- this remark isn't only about perl). The same thing that makes it perfect for sloppy one-offs makes it slow for everything else, but slow is relative, given computers with several billion instructions per second at your disposal. In lots of cases, the time required to write the program is vastly greater than the time required to run it, so writing in an easy and forgiving language where you can dash off working code in thirty minutes instead of a couple of days is totally worth it.

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Comment Re:Wait, what? (Score 3, Interesting) 379

And C is the best to write operating systems (and a lot of other stuff) in and APL is actually pretty nifty for writing certain kinds of vector code and...

Personally, I still love Perl and use it by preference when I need a short one-off program that doesn't have to be fast, especially one that does a lot of parsing. It is a great on-the-fly translator, and is often used to facilitate data conversion of one sort or another because it is so easy to use for that purpose. I have written far more complicated stuff -- actual interactive GUI applications -- in Perl, but that's where one is probably pushing it outside of its area of primary utility and I probably won't do that again. And yeah, one of the best features of Perl is its ability to split lines and do regex processing in a syntactically compact way. Tools like awk/sed/bash are also very useful for doing simple stuff -- pattern matches and substitutions -- but sed rapidly becomes arcane to the point where one has to keep a library of sed 1 liners or examples handy to remember how to pull the third octet out of an IP address, add 24 to it, and write it back or the like. In Perl doing this takes several lines of code (if you want the result to be readable) but it is easy and robust to code and understand. I used to use awk a lot (15-20 years ago), but Perl completely superceded that. I do still use sed simply because s/aaa/bbb/g is so damn useful on the fly, more so if you chain several sed conversions and other stuff together in a pipe. But once the complexity passes a fairly low threshold, Perl is very much a tool of choice.

Of course it is not unique. Nowadays, lots of people like other similar languages e.g. python that serve more or less the same space. But arguing about which of the available languages is "best" is a fruitless exercise. Philosophically they are very different. Some people like what I would call "fascist" languages (where python is in that category IMO) with strict rules on e.g. indentation and structure. Some people like loose, free languages that don't care how you indent and use brackets instead. Some people like procedural languages. Some people like object oriented languages. Some people are agnostic and like languages that do both, each in its place. And whatever the programmer likes, there is also the task -- some tasks manipulate data or perform computations in procedural ways, some work with data objects.

Personally, I think any rumor of the demise of Perl is likely exaggerated and premature (and I'd want data to support it!) I use it all the time, and obviously I wasn't surveyed. A lot of the rise and fall of scripting languages is dictated by what schools are teaching and what people need in jobs, and these days it is dominantly java (or javascript), python (because it is easy to teach structured programming in python), php (because it enables web programming), and even "html" (which isn't really a programming language but so what). For web programming -- a major if not the major marketplace for programmers -- and even for database programming (web interface to database) this set makes sense. Perl was popular early on for writing web scripts because it worked, but it wasn't really designed for that purpose and languages that were (but were otherwise remarkably perl-like) eventually won out. So what? That wasn't what Perl was written for, and it's not what it does best.

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Comment Re:I Almost Hate To Say This (Score 1) 263

Only a few quibbles. First, it doesn't explain a known issue with the models. It is a potential explanation for one of many known issues with the models that remains to be demonstrated as an explanation. Second, it may well invalidate the overall predictions in the specific sense that altering the circulation patterns enough to affect weather -- the assertion of the article -- is more than enough to alter heating and cooling efficiencies, albedo variation, cloud distribution, and more. In a highly nonlinear general circulation model, this is more than enough to alter the actual predictions for e.g. climate sensitivity.

Furthermore, if it alters the UHI data and corrections made thereof, it alters the data that goes into the models. It also alters -- and from the sound of things lowers significantly, over a widespread area -- the claimed amount of observed warming, as a function of time as urbanization itself is a time dependent trend. This actually has secondary support in the form of UAH and RSS satellite observation, which has differed from GISS and HADCRUT (especially after ongoing "adjustments") by a time dependent positive trend. Correcting for this (by effectively cooling the present relative to the past) would actually put the major temperature sets into better agreement over the last 33 years.

The waste heat production of humans is absolutely irrelevant compared to solar heating as a direct source of global warming, but it is a well-known and consistently underestimated source of local warming in the weather stations used to create land temperature estimates (as has already been shown in peer reviewed publications, if a glance at e.g. the Weather Underground local weather station maps surrounding any urban center isn't enough to convince you). This suggests that the effect is not as spatially confined as previously believed and to accomplish long range effects at all has indirect effects that exceed the local ones. This is not impossible -- I've read papers that suggest that the mere presence of the turbulent air downstream coming off of the vanes of a windmill farm cause significant mixing of the air near the surface that would otherwise be stratified over an area of tens to hundreds of square kilometers, affecting the mean nighttime temperature over all of this area.

The proper issue regarding global warming is not whether or not it has occurred or is occurring -- the world has definitely warmed on average since the LIA, with almost all of that warming occurring without the help of carbon dioxide. Nor is it whether or not increased carbon dioxide will all things being equal cause more warming -- that's simple physics, although the net warming expected from carbon dioxide alone is not particularly alarming. It is whether or not we know enough about the nonlinear feedbacks in the chaotic system to be able to build general circulation models at all with predictive value ten to a hundred years into the future. It is about the climate sensitivity.

Any negative adjustment in current temperatures simply exacerbates the already serious problem those models face -- there has been no statistically significant warming for the last 14 to 16 years, roughly half of the entire reliable RSS/UAH record. The warming visible over the entire record is at the moderate rate of 0.1C to 0.15 C per decade, in almost perfect agreement with the warming expected from CO_2 alone, with neutral feedback. Almost all of the warming occurred in a single spike of warming that is precisely correlated with the 1997-1998 "super El Nino" -- effectively flat before that, effectively flat after that. Carbon dioxide, in the meantime, has inexorably crept up.

Personally I don't think this falsifies assertions of possibly catastrophic global warming, because we don't know enough about the timescales, the chaotic dynamics, the feedbacks, neglected effects like the extended UHI effect discussed above, neglected effects from solar-driven stratospheric atmospheric chemistry, the fractional contribution of black soot and more (there have been papers on all of these recently). I think that this is a damn hard problem, and that far from being settled science, it is absurdly unknown science -- we don't have good global data even now for the 70% of the Earth's surface covered by ocean, and while ARGO will in a few decades improve this, it is decades away from having enough buoys to give us an accurate picture of temperatures and currents and heat content down to the thermocline globally. And while the satellite records for the last 33 years are good, consistent, and global, they are far too short -- they don't span even one whole cycle of the major known global decadal oscillations, oscillations that are known to significantly affect heat transport and global heating/cooling patterns and efficiencies.

In a few more decades we might understand the climate system well enough to make reliable decade-scale predictions. At the moment, every year without discernible warming post 1998 increases the divergence between the predictions made at that time and the present. This doesn't falsify global warming (which really is beyond question anyway), anthropogenic global warming (still a somewhat open issue), or high-sensitivity catastrophic anthropogenic global warming, but it certainly doesn't support the latter (catastrophic) prediction, and is gradually lowering the upper bounds of any sort of reasonable estimate of the climate sensitivity. That doesn't mean that temperature might not spike up this year or next year to rejoin the high sensitivity predictions, as well. Personally, I rather hope not. If climate sensitivity is basically neutral or even net negative as far as feedback is concerned, that is rather good news for humanity, and either one is well within the error bars of satellite observation. If one views the ocean as a rather large global thermometer (which it is) then the SLR record should also be very reassuring in that regard.

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Comment Re:The key question becomes (Score 1) 163

OK, seriously, let's try doing some arithmetic. The energy cost per kilogram of lifting something into low Earth orbit is half of it's escape energy. Escape speed is roughly 11,000 meters per second, so that energy is 1/4 x 121 x 10^6, call it 30 MJ/kg. Multiply that by something like 1000 (maybe more) due to rocket inefficiencies where you have to lift the fuel to lift the fuel to lift the fuel that lifts the payload. But it doesn't matter -- lift it at 100% efficiency and you're already dead. So lifting sand into orbit to melt it is enormously stupid. One might as well melt it in solar furnaces here on Earth, except that this is silly, joule for joule you'd be far better off collecting a megajoule of solar energy and converting it into a hundred kilojoules of electrical power. Even cheap low efficiency solar can manage that, and the return is at least twice that of silicon nanoparticle energy. Indeed, you'd be far better off taking the silicon you purified and turning it into solar cells -- those are already close to break even with at least some sources of energy in some locations, and a kilogram of silicon used that way can generate at least tens of watts (probably order of 100) for at least 20,000 seconds of an 86,400 second day. That's order of two megajoules a day, for a projected lifetime of 20 years. And note well, that is still not an economic win without exception in all locations when its amortized cost is compared to the value of commercial coal or nuclear or natural gas generated power, and it is only available when the sun shines, because kilowatt-hours of commercial electric cost anywhere from 6 to 16 cents in most locations, and at 6 cents it takes effectively forever to recover the cost of $1/watt solar cells. At 16 cents it breaks even to wins a bit with a seven to ten year amortization, and hence is a not unattractive investment. At 10 cents it is marginal (call it 5 watt-hours a day, 200 days to get a kw-hour and thereby earn 10 cents, 2000 days to break even on the solar cell itself, 4000 days to break even on installation, inversion, and the cost of the money. That's eleven years before you start to turn a profit, more if you install a battery to store the energy instead of resell surplus back to the grid. 16 cents drops it to under seven years, which starts to look attractive.

Saddest of all, in seven to ten years, solar cells will very likely go down to 50 cents a watt or even less, at which point they'll become attractive at 10 cents a kW-hour, a no-brainer where electricity is more expensive, and still it won't be a suitable solution for powering civilization, not without a serious storage and transportation technology to back it up. Otherwise it is at best a load leveller for conventional plants.

As I said, I can't really see any good reason to invest in silicon nanoparticle generated hydrogen gas powering fuel cells to make electricity except -- perhaps -- for exotic "one off" problems like a military application or a space application with nonlinear constraints or benefits. And even for the military, if they think this is a winning solution I think they're out of their minds. Somewhere in there common sense has to come into play.

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Comment Re:The key question becomes (Score 2) 163

Because Obama hasn't given me a call yet to make me the offer, I suppose. I'm not sure I accept it if he did -- it has to be a thankless job these days and I'm enough of a climate skeptic to think that energy resources need to have net positive present cost-benefit before implementing them on a broad scale. Until then research and even prototyping is lovely and worthwhile, but no large scale implementation at a loss until it results in something at least cost-competitive with existing fully developed resources.

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Comment Re:The key question becomes (Score 5, Informative) 163

Where does silicon come from? Silicon dioxide, a.k.a. "sand". How tightly is it bound? Very, very, very tightly. Indeed, a whopping 910.86 kJ/mole. So it requires at LEAST this much energy to turn sand into silicon and oxygen, except that one cannot electrolyze or reduce it until it is molten, so add to this enough energy to melt sand, after raising its temperature to some 1500 C. Then, one has to engineer "nanoparticles" out of the purified silicon metal. At a guess -- only a guess, of course -- this involves heating the silicon to the vaporization point and either vapor depositing it on a suitable substrate and scraping off the nanoparticles or spraying silicon vapor into a suitable medium that causes it to condense out small particles and then filtering or otherwise separating out the 'nano' particles from those that are merely small. Sounds like more energy to me.

At the end of the day, you can get at most the 250 or so kJ/mole back from the hydrogen gas produced after the silicon nanoparticles steal the hydrogen back from water. I think it would be an absolute miracle if it this is as much as 10% of the energy invested in making the nanoparticles, and the energy costs are probably at most half of the total manufacturing costs. Down to 5%. Multiply by roughly 50% again (efficiency of fuel cell).

This "Fermi estimate" of the probable economic efficiency is on the order of 2.5%, then, compared to the cost of just buying electricity or any other form of concentrated energy. Even if I'm too aggressive in my pessimism, 10% is a pretty safe upper bound. I'm not seeing this as a game changer. Gasoline or other hydrocarbons are still the gold standard for readily available energy density at ballpark 35 MJ/liter, and don't require investing 20 times the energy eventually recovered in their preparation.

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