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## Comment Re: Islam's relationship to modern science (Score 1)330

I find a lot of people who are agnostic or atheist have actually made science their religion. Most aren't even practicing scientists, and instead of looking to the scientific method to teach them new ideas, they have "faith" in theories despite science not yet having proven or disproven them. They use science as their religion not to further science, but to attack religion. Your comments are pretty close to putting you in this bucket.

"Science" is not a religion, it is the set of interlocking assertions that have the strongest, mutually supporting evidentiary support. It is literally what it is best to believe about the real world according to an actual standard. It does not assert perfect truth, it asserts probable truth, provisional probable truth at that. If you want to actually learn something about the reasoning process involved, I would recommend E. T. Jaynes' "Probability Theory, the Logic of Science". You might also want to peruse Richard Cox's monograph "The Algebra of Probable Inference". The difference between a religious text and these two works is so profound, so obvious, so glaring, that perhaps you will reconsider your rash statement that science is a religion. These books establish, via a minimal set of axioms, a direct connection between evidence and networks of probable beliefs -- they provided mathematical support and a proof of sorts that it is better to believe things given evidence than to believe any random notion that is asserted by anyone, anywhere, for whatever reason that is not supported by evidence, that contradicts beliefs that are supported by strong evidence, or that is contradicted by the evidence itself directly.

I would offer examples -- but is there really any point? There are a near infinity of possible religions. There are quite a few actual religions, religions that contradict one another on numerous points, and the number swells to a really large number if one allows (as one should) all of the religions ever believed by any vagrant tribe throughout history, and all of the named variations on religions loosely shared between tribes.

For starters, probability theory would dictate that even if one knew that precisely one of these variants was precisely true, it is rather improbable that your particular beliefs out of this set of possibilities is correct. It isn't even probable that your beliefs come from a major family that could be correct. The odds are against any given religion being correct before you examine evidence. Without evidence (and a general agreement as to what might constitute evidence) the best one can do is make all of these possibilities equally likely, that is to say, nearly infinitely unlikely.

Then one can systematically examine the scriptures and claims of each and every religion. All of the major religions tend to claim in their scriptures that they are perfectly true, inerrant, and the Word of God made manifest to be disbelieved in a single tittle at peril of whatever memetically evolved punishment suited its human creators at the time. If you've studied Godel's theorem, you should realize that this is a clear signature that this particular claim is false. If you want to identify a liar, look for the man who claims "I never lie". Nevertheless, it doesn't take five minutes of reading scriptures associated with the world religions making claims about God and the world to find numerous statements that are open absurdities, claims that are directly contradicted by everything we have painstakingly learned to believe on the basis of sound reasoning and experimental evidence. In other words, even if you allow the condition of contradicted by beliefs supported by strong evidence to apply to religions themselves, the contradictions between the religions reduce the believability in the entire set.

Is this in fact not only the case, but obviously so? Of course it is. Any believer in a major scripture-based world religion (excluding diffuse deism disconnected from any dogma or scripture as a world religion) believes in their religion and its scriptural claims as "evidence", but has no difficulty whatsoever in rejecting the claims of all of the other religions as absurd. If you are a Christian, you are not a Muslim. You aren't a Muslim because you think that Muhammed was (fill in the blank) mistaken, lying, misled when he claimed, as he does throughout the Quran, to be taking dictation from God/Allah. If you thought this was true, you would be a Muslim instead of a Christian. As for why we would doubt it even though it is written down, there are lots of things that are written down that aren't true. Documents making claims for absurd miracles, bad science, and openly questionable ethical assertions are things that we automatically reject as probably untrue -- unless we have been raised to think that they are true beyond any question or exposure to critical thinking.

You asked what is absurd about the Book of Mormon. Do you want a list? Claims of imported old world plants and animals utterly absent from the new world? Steel swords in the new world? Compasses used for navigation before compasses were invented? The wrong geography for the old world? The constant assertions that white folk are good and pure and dark folk are not? The idea that Joseph Smith dug up gold plates covered with strange writings in the fields of upstate New York, and managed to decipher them with divine help? The terrible quality of the writing? There is an entire musical (to which I have tickets) poking fun at the Book of Mormon, which is nothing compared to the South Park episode which openly, and quite rightly, mocks it. Or you can go here: http://www.skepticsannotatedbi... and click on the lists of "problems" all neatly excised and commented on. Good luck with the hermeneutics (the entire discipline devoted to trying to pretend that problems in scriptural writings aren't).

In the end, of course, it ultimately comes down to evidence. An atheist doesn't necessarily believe that there is no God. They simply see no reliable and reasonable evidence that God exists. Lacking this, there is no good reason to reject the null hypothesis that there is no God, any more than we need to reject the null hypothesis that pink unicorns are not real animals prevalent in my back yard. I'm happy to believe in pink unicorns. Just show me one. Well, really you need to show me more than one, plus enough supporting evidence that I can be convinced that I'm not looking at a dyed horse that has undergone a painful surgical procedure.

What exactly, constitutes reliable, inarguable evidence in favor of the existence of God? What constitutes even weak evidence in favor of the existence of God? Our feelings? Question begging "logical" proofs? Scriptural writings that are mistaken on almost every single point that they can be checked on, that make absurd claims every few pages, things that if they were claimed today we would dismiss without wasting a minute on them?

So, my friend, while I am, as it happens, a professional scientist -- a theoretical physicist, in fact -- who majored in physics and philosophy as an undergraduate and whose favorite philosophy professor was a student of Bertrand Russell, and who writes about boring stuff like ontology and semantics and semiotics just for the fun of it, I deny any claim that science is a religion. The scientific worldview is the collection of mutually (reasonably) consistent, evidence supported beliefs about the real world. One can give a good reason for believing every single thing one believes in this worldview. If you doubt any of its assertions, there is an open and above board methodology for resolving the conflict, one that will, in general, convince any reasonable person in possession of the same evidence and supporting network of beliefs.

How, exactly, can that be compared to the primary reason -- seriously -- that anybody on Earth believes in their religion: Their parents believed in it and raised them to believe in them and (often) punished them if they questioned it and rewarded them if they accepted it, if only in subtle ways? If you don't believe that the acceleration of gravity is roughly 10 meters/second^2, we have an easy way to resolve the question if you are at all reasonable. If I happen to think that the Holy Trinity makes less sense than heretical Arianism, how exactly are you going to resolve the question? That's the difference between the two. Scientific truth is derived from observations of the real world and can be validated over and over again by anyone that doubts it. Nobody can answer the Trinity vs Unity question on the basis of evidence, because there is no real world evidence worthy of the name for either one.

rgb

## Comment Gravitational locking already? (Score 1)96

Seriously? The moon is gravitationally locked now, sure, but the Earth (and moon) still being liquid/hot when it slowed to a lock? I don't think so. For this to be plausible the moon would have had to coalesce, in an orbit, with nearly zero spin angular momentum, which seems absurdly unlikely. Otherwise, like a bird on a rotisserie, it would have been "roasted" pretty much equally on both sides. So maybe, but I doubt it.

## Comment Re: Islam's relationship to modern science (Score 3, Insightful)330

The census in prose with the lovely insertions of slaughtering the Midianite captives including women and children EXCEPT for the young virginal girls who were given to Moses' soldiers to -- wait for it -- rape and enslave, followed by a half page of tallying up the loot of a genocidally slaughtered civilization and recording how much of it Moses, the priests, and the war captains got. If one rewrote it and published it as an account of what the ISIS "caliph" did with, say, Beirut or Damascus, the world would be shocked and cry out everything from genocide to infanticide, but because, well, it's MOSES, well then it is OK. Even Jesus loved Moses, and entertained the man himself during his transfiguration.

Come to think of it, a lot of what ISIS has done does fit right in with Old Testament reports of God's Own People.

rgb

## Comment Re: Islam's relationship to modern science (Score 5, Interesting)330

This is the hardcore Salafi doctrine by which people like Daeesh operate by and it's theologically valid, though batshit insane.

HOWEVER, only about 70-80% of Muslims are Sunnis and of those maybe 10-15% are Salafis.

Oooo, let's do the arithmetic. There are roughly 1.6 billion Muslims (sources: multiple, although many would go as high as 1.9 billion and rising). Let's be conservative and go with 70% of the smaller number -- 0.7 x 1.6 = 1.12 billion are Sunnis. Of these (again, being conservative) 10% are Salafis. That means 112 million Muslims are Salafis! Or as many as 200 million, of one uses the higher end of that projection. Of the Salafis, roughly 10 million are estimated to be Salafi Jihadists. So sure, less than one percent, but the original numbers are so large that the actual numbers are still huge, if you view them as a potential army and recruiting ground for violent Jihad.

So what you are saying is that the Daeesh are a huge bunch of psychopathic assholes led by an eloquent sociopath from Baghdad, because while it is true that all Salafis, no matter how batshit insane the theology to which they subscribe, are not Daeesh Jihadists, they are at the very least a fertile ground for recruitment and have the potential to become a bandwagon several hundred million strong if ISIS appears to be succeeding, and it also strongly suggests that they aren't all foreign psychopathic assholes. There is a rather large pool of the domestic home-grown type.

All of which was true for Al-Queda as well, as it isn't just Salafi Jihadists. Jihad is comparatively ecumenical in Islam, and while it is not necessarily violent, it can easily become violent, often quite rapidly. There is a large disaffected population of young, volatile Muslims worldwide. In some, but not all, non-Muslim countries they feel highly marginalized. In many Muslim countries the governments are so corrupt that even though Muslims per se aren't marginalized, life is worse than it is under the foreign non-Muslim governments, marginalization or not. Then there is the antique Sunni vs Shia problem -- a division that perpetuates Muslim on Muslim violence and weakens Islam immeasurably as its adherents perpetually discover that the enemy of my enemy is a better friend, Muslim or not. Far too much of Islam is tribal culture still living in the 8th or 9th century, but dreaming of the 12th and 13th centuries when it was a, perhaps the, dominant world power. Young Muslims see this division and are easy meat for any charismatic religious leader who promises to end the rift and restore Islam to its "rightful" status as a, no, as the dominant world culture.

At the end of the day, though, there is the Quran. And the Quran is a stupendously violent document. It was a revolutionary document back when it was written, designed to generate an us vs them mentality and create a social and religious identity to support the establishment of a violently conquered tribal empire. It succeeded. Its memes are strong. This makes the followers of any sort of literalist interpretation of the Quran enormously dangerous to non-believers, because it quite literally makes converting or killing or enslaving them a holy duty, especially if they in any way interfere with or refuse to live under the religious laws of Islam, believer or not. This isn't really arguable -- one can just read the damn thing and see for yourself (but as usual with holy scriptures, nobody does, they just prefer to quote what somebody else says about them in a pious way). Being a liberal Muslim is even more difficult than it is to be a liberal Jew or Christian, and that really isn't easy if one reads, say Numbers 31 in the OT to see how God really feels about the Midianites and non-Jews in general, or reads Leviticus to see how he really feels about slavery and women. In all cases one has to sort of elide all of the passages that don't agree with what you want to believe is The Good, and pretend that they aren't really there, while emphasizing the passages (and there always are some) that do agree with what you want to believe in. Doublethink. Cognitive dissonance. And a sort of wilful dementia.

Locke, Thomas Jefferson, and a handful of others created new memes a few hundred years ago. These memes were not found in any religion. They were in some ways openly heretical, anti-religious (and still are). The meme of the right to freedom is in direct conflict with pretty much all of the world religions, but nowhere is the contrast so stark as it is in Islam, because Islam openly supports slavery and comes very close to commanding it as the appropriate thing to do with non-believers who refuse to convert, if you don't want to kill them and they aren't "people of the book" who are willing to live under the same first millennium social culture (to whom it offers very limited protection). Freedom isn't in there anywhere. No right to life. No liberty. No right to pursue happiness. Absolutely no right to change your mind about Islam, or any freedom of thought whatsoever regarding Islam.

But nobody reads the Quran, any more than they read Numbers, or Leviticus, or Acts, or the Book of Mormon (which is a REAL hoot). And we pay the price of our illiteracy and our unwillingness to apply the rules of critical thinking and scientific reasoning to their contents, and will continue to pay it, over and over, until we/the world collectively come to our senses and stop treating antique religious writings as being somehow privileged in morality, ethics, social and political science, ordinary science, and the perpetual self-assertions of truth and communication of what an invisible and undetectable being really wants us to do and believe.

rgb

## Comment Re:This has all been hashed out on /. before... (Score 1)85

Sigh. I pitty me, since you are obviously clueless about more things than I can easily fix.

Gravity can add energy to things with "100% efficiency", but only after you've done the work of raising them up in a gravitational field. Pretty much the same thing is true for electrostatic energy. Magnetic fields do no work (seriously, and don't argue with me as I'm teaching electrodynamics at this very moment and You Will Be Wrong of you say otherwise and I will cheerfully prove that:

dW/dt = q(\vec{v} \times \vec{B}) \cdot d\vec{l}/dt = 0

as an identity (d\vec{l}/dt = \vec{v}, and A dot (A times B) is zero). I suppose one can do no work with 100% efficiency, but your entire comment is three lines of pointless.

Now, I could wax poetical about the second law of thermodynamics and the presence of irreversible losses in even simple things like dropping something macroscopic in an actual gravitational field that cause some energy to be diverted to heat, causing a loss in thermodynamic efficiency, which I actually can define as well, but you are quite right. I was referring to the horrendous inefficiency of adding somewhere between 32 and 64 MJ/kg to an object lifting it with rockets. You know why? Because (and follow this argument carefully, because it is pretty important):

That's the only way we have to lift an object to Earth orbit, be it low or geosynchronous.

Sure, there are fantasies about alternatives. For example, a great Heinleinian favorite is the linear accelerator (and yes, I've read all of Heinlein's works, many of them too many times to count). Now, go out there and actually cost one out, and figure out how you are going to solive the many, many engineering problems associated with accelerating an object to order of 11.2 km/sec plus whatever you need to punch through the atmosphere, without it burning to a crisp and without thermodynamic losses at every step along the way -- from the power plant that makes the electricity to the wires that carry the power to the currently imaginary rings aligned along some currently imaginary mountain ridge that will fire an undesigned and improbable payload container along a track some hundreds of unflattened kilometers long (at least if you want to contemplate firing humans inside).

Then there is everybody's SciFi favorite, the Space Elevator. In this fantasy, somebody puts something nice and massive in geosync orbit above a land point on the equator. Then they imagine -- and I do mean imagine -- building this really, really long cable made out of Imaginarium, an imaginary material that is so strong that it will not snap under the stress of its own weight when dangling from 5 earth Radii out back to the surface, and that can (what the heck, imagination is free!) carry a payload as well! And then, it is flexible enough to be run in a continuous belt around a spindle in the asteroid, under tension, without doing bad things to the asteroid's "orbit", which would not any longer be at 5R_e because, well, you are pulling down on it with the tension in the belt.

Now the idea is to turn a crank and lift things up the "elevator" to not-exactly orbit! As the crank turns, one "car" would ascend while the other descends, so you'd only have to lift the "weight" of the payload, at least if we ignore friction and the like in the sprockets under enough tension to lift the weight of 20 to 30 thousand miles of cable plus the payload.

Now the owners of this particular fantasy do tend to leave out a handful of, um, "obstacles" to their pretty little scheme. For example, the fact that building it would cost a few hundred trillion dollars, the fact that it isn't even clear that materials that could support their own weight from the pseudorbit to the ground could even theoretically exist, given that the strength of molecular bonds is capped at something like eV, the molecules themselves have a minimum mass and volume, and I suspect (but haven't proven) that a simple scaling relation would show that the cable is literally impossible given our current physical laws. But my favorite problems are the dynamics problems. You might not know it (given your obvious general ignorance of physics) but when things rise or descend, they are subject to pseudoforces in the differentially accelerating frame. As things rise from the equator, they are going too slowly for points with the same angular velocity directly above them and are deflected antispinward, that is to the west. As things fall, they are going too fast (to the east) for the points below them so they are deflected in the frame of the point on the ground directly below them to to spinward, the east.

The asteroid you are using as an anchor is being pulled down by the cable. Thus the tension T in the cable has to be added to gravitation to form the net downward force. This means that your orbit equation becomes:

GMm/R^2 + T = m\omega^2 R

where R is the radius of a stable orbit. Omega is fixed by the period (geosync), G and M are fixed, and as a consequence one has to solve a quadratic to find one of two possible stable orbits where the tidal forces compensate for the cable tension.

But now you put a load on the cable -- that's what it is for! T goes up! Even if it is by a little bit, it goes up for a long time as you lift something tediously up to the asteroid.

Mr. Asteroid is then unhappy. The downward force has increased. The rising object hast the wrong angular momentum, as well. It exerts both a force on the asteroid which forces the asteroid to change its period and/or R and it exerts a torque on the asteroid as it has to speed the object up laterally to give it enough angular momentum to be able to match.

Is this angular momentum mismatch a serious problem? You betcha! A point on the equator is travelling east at roughly 1000 mph. The asteroid is travelling east (directly overhead) at roughly 5000 to 6000 mph (tell me what T is first, best I can do is estimate without solving the quadratic, assuming T is still much less than the weight of the asteroid). That means that lifting the mass to the asteroid is precisely equivalent to shooting the payload at the asteroid from the east at 4000 to 5000 mph.

No, no, no, I don't mean heating it up -- well I mean that as well as an inelastic collision is still an inelastic collision even if it happens slowly -- but that is a substantial transfer of angular momentum to your geosynchronous asteroid. It is no longer geosynchronous. But as it moves it stretches the cable. Oh my! Just how much energy is stored in that cable and what will happen when -- not if -- it breaks?

Finally, the cable would be an obvious target for every single disaffected minority on a world composed solely of disaffected minorities and crazy folk who think that building one would give us Space. Even if we pop for the hundred trillion, invent ion drives that can use sunlight to stabilize the asteroid while the lift is operating (but wait, aren't we back to rockets again? Oops), come up with Imaginarium, it would be child's play to damage the cable enough that a defect would tear it apart. It wouldn't last a decade. One would have to fortify it for a hundred miles around and buildin serious can't fail defenses against...

rocks. Oh darn. Now we've got asteroids in orbit and humans up there too and ion drives and if a single crazy person gets the idea of dropping a rock (or project Thor flying crowbar) on the base, there goes 100 trillion, the lives of everybody in space that will then starve for resources delivered from Earth, the countless dead from what will happen to the ground when a 20000+ mile length of by design nearly impervious cable comes crashing down at thousands of miles per hour, in pieces.

Now, you want to try for laser propulsion? As it happens, I actually think about all of this stuff, and know enough to think about it fairly sanely as opposed to in SciFi fantasyland. I love SF. I write SF. But I can differentiate SF from reality. Can you?

In the meantime, let's be real, shall we? A very reasonable estimate of the cost per kilogram of lifting something to geosync right now, with any technology available in the foreseeable future is order of 100x 32 MJ/kg. Sure, maybe you could get by for half that with cleverness and reworking existing engineering. Or, perhaps it is two or three times that by the time an honest accounting is taken. It doesn't matter. Even if it were just 32 MJ/kg, it wouldn't be worth it to send solar cells into orbit. It will never be worth it. It is insane to think it could be worth it. At absolutely most one can get an order of magnitude more power out of an orbital cell over a 24 hour day than one can get from the exact same cell located on useless real estate where the sun always shines here on Earth. The amortization time on the cost to lift it to orbit is infinity, because it cost 1000s of times the cost of the cell to put it in orbit, and you get hit by multiple inefficiencies in generation and transmission that eat most of your order of magnitude advantage before you start.

Now can we stop? If you want to play the physics idiot game, I'm happy to do so, but again, I am an actual physicist (and have thought about most of these thing off an on for decades) and you're not, and you will lose.

rgb

## Comment Re:This has all been hashed out on /. before... (Score 1)85

Uh, I teach physics. In fact, I'm about to be late for class. 64 MJ/kg is escape energy, circular low orbit is half of that and I actually did and can do the computation(s) myself. In my head. Now, you figure out how to add 32 MJ/kg of total energy to something at 100% efficiency. Let me know how it is done.

rgb

## Comment Re:Linear motors? (Score 1)77

Sorry, blew my mod points commenting myself or I'd mod you up, AC! There are probably more than two alternatives, though. For instance, just building better batteries, growing GMO biodiesel, perfecting fusion and just using plug chargers or stationary induction chargers once the grid is so ridiculously power rich that we can afford to drop 50+ kW power points all over the place.

## Comment Re:What an incredibly stupid idea... (Score 1)77

And you have the fundamental problem that solar cells are basically incapable of pushing an actual car with any surface area they are likely to be able to carry, let alone their own surface area. As I noted above, it costs roughly in 1 kW-hour to travel roughly 1 mile. That's kilowatt-HOUR, so even if your "car" were sitting on the top of the atmosphere and getting full sunlight at perihelion, its surface area at 100% efficiency wouldn't provide this much energy in anything like the amount of time you might like to drove that mile.

A 5 KW plant covering 10s of square meters on top of a house, running all day, on a good day can harvest the energy content of a single gallon of gasoline. Sure, efficiencies have to be factored in and can make a difference of a factor of 2 or 3 either way, but basically, unless you build a car with an enormous roof covered in ultralight solar cells, you're not powering a car on sunlight.

As I also pointed out above, there do exist electric "cars" (e.g. the ELF) that can run for a short commute on a daily basis on the sunlight they can harvest or very near that. But these cars are legally bicycles because they are light enough for a single person to pick up and have a top speed of maybe 20-25 mph without a pedal assist.

rgb

## Comment This has all been hashed out on /. before... (Score 4, Insightful)85

... and there is simply no sane way that paying a MINIMUM 32 MJ/kg to move a kg from the earth's surface to low earth orbit -- that's the minimum that assumes perfect efficiency, which is all by itself pretty funny, multiply it by maybe 100 or 1000 to get an actual estimate -- is ever, ever, ever, ever, ever going to give you a ROI compared to installing solar cells on earth at an identical cost. And then you have to extra problem of getting the energy you harvest in orbit to the ground, which either involves putting a huge receiver somewhere to pick up relatively low intensity downbeamed microwaves (at some major hit in waste heat an inefficiency) OR using less ground area but building a super-maser in orbit that can cook an entire city to extra crispy in a few minutes.

What could go wrong?

Once again, when confronted with an idea that is so very, very, very far away from economically feasible or sane, the right thing to do is club the person suggesting that they will implement it all, with our money (natch!), while keeping ownership and control of the death ray -- I mean "orbital power station" -- is to knock them down and club them with a heavy blunt instrument until they stop twitching.

The guy in the movie about actually pretty much said just that. The only thing it might make sense to lift into orbit for power is solar cells for powering SPACE devices, vehicles, living quarters, or fusion plants once we manage to build one, assuming we can make one small enough and light enough and capable of rejecting heat in a vacuum enough to be able to operate for decades on a small fuel load.

rgb

## Comment Re:What an incredibly stupid idea... (Score 1)77

it all depends on how many of these things you need to embed in a mile of roadway in order to transfer enough power to drive a mile at whatever speeds...and it's too early to know how hard that is.

Not so hard, if Fermi didn't live in vain. One gallon of gasoline contains around 32 kW-hours of energy. One car gets (on a good day, an efficient car) around 32 miles per gallon. One car therefore requires roughly one kW-hour of energy to go one mile. Unfortunately, that one car on a normal roadway drives that mile in roughly 100 seconds (all we care about is orders of magnitude, it might be somewhat less or a somewhat more in a city). There are 3600 seconds in an hour, so we require the power to be delivered at the rate of roughly 36 kW, continuously, in order to maintain the energy content of the car and restore one kW-hour of energy to the car in the time it drives a mile. However, it won't be continuous. If the coils are too close together, one will have a serious problem with mutual inductance and back voltage -- the neighboring coils will be working against one another. If we assume a reasonable geometry of 10% of the roadway occupied by the little puppies (that is, allowing for the coils to be actively charging your car 10% of the time as it drives, continuously), it increases the power requirements to be 360 kW.

Now, let's see. The average house uses around 2 kW in steady state (more or less in variable peaks). My neighborhood has around 180 houses. Each coil in the roadway has to be ready to deliver as much power as my entire neighborhood is using on average in order to deliver 1 kW-hour to the car in ten seconds of actual connection time while it is tooling down the road at 40 miles an hour. At the same time, there will be a car off to my side, a car behind me, two cars in front of me, all drawing power from whatever source at these phenomenal peak loads. Worst case scenario, the cars in the roadway line up spaced out in traffic by the ten meter spatial period of the 1 meter coils. Now we have (say) 100 cars all getting charged synchronously, pulling 36 megawatts peak power in a single kilometer of roadway. Multiply it out a bit because people want to think in miles instead of km, and your roadway has to be able to provide (for engineering robustness) roughly 50 MW per lane per mile. A four lane highway 5 miles long would require a GW power plant all by itself to be able to provide peak demand in resonance. And in case you think you can get away with smoothing it out (which is a silly assumption as cars naturally space out in ways that can create a resonance -- they are strictly antibunched compared to a poissonian, and the antibunching is just in the right range to tap whatever spacing you are likely to use) even if you divide that number by ten in order to try to get funding and be paid to investigate an absurdity, every fifty miles of a four lane highway (two each way) would require a GW, 2 GW if you plan to let cars drive at 70 mph, and that still won't have much of a margin, 4 GW per 100 miles.

There is a reason cars burn gasoline (or diesel, or peanut oil, or even ethanol). That reason is that the energy density of gasoline is enormous. A gallon weighs a bit less than 8 pounds and contains 33 kW-hours of energy. The best battery on Earth currently provides energy density of under 3 kW-hour in the same 8 pounds. The simple, hard truth is that gasoline is still about an order of magnitude ahead of our best, most expensive batteries in terms of energy density if not absolute volume. This provides electric cars with a host of reasons to lose any fair competition with them. In order to charge an electric car with the energy equivalent of a single gallon of gasoline, you have to deliver 33 kW-hours of energy. If I put a 5 kW solar system on my roof (at a cost on the order of $10,000) and devoted it to nothing but keeping an electric car charged, I would be able to get no better than the equivalent of 1 gallon of gasoline into the car per day, assuming that I manage to draw peak power for six straight hours during the middle of the presumably sunny day. At$2/gallon, it would require 5000 days just to break even on the cost of the solar system neglecting all amortization and the costs of the money. Throw in the enormous premium price of the electric car in the first place, and hell will freeze over before I see a return on my investment.

At $0.10/kW-hour, the electrical cost of that gallon of gasoline from the conventional grid is$3.60. We thus start out with a dead loss (and note well, I'm completely ignoring all inefficiencies along the way -- this is a Fermi estimate after all, so one might arguably break even but one certainly won't win and one could lose by a factor of two MORE than this pretty easily, especially if you live in a state where they have pushed the cost of electrical power up by a factor of two as part of the ongoing crusade to shut down civilization). So to own an electrical car you pay the double penalty of 2-3 times the cost up front plus the promise of paying a premium for fuel of roughly 2 to 1 for the indefinite future (again, easily for the lifetime of your vehicle). I own two Priuses, and the first one we bought when the price of the puppies was easily twice the cost of high end small car with similar capacity. Yes, it gets (say) 2x the gas mileage of that alternative car, but the extra $20,000 would have bought an extra 7000 gallons of gasoline and the marginal difference in mileage is 7000 x 25 = 175,000 miles. So if we drive the first Prius to a total mileage of 175,000 AND ignore the increased cost of financing the purchase (all up front money comes with a cost relative to unborrowed running expenses) AND ignore the cost of replacing the main battery pack at least once during that time -- oh, hell, let's not ignore those things, since they tally up to at least$10,000 more over that lifetime -- if we drive the car out to almost 300,000 miles and don't have to replace the battery system more than 2x we'll break even.

To me that means "we'll never break even" and I pointed this out when we bought it, but my wife wanted it. Oh well. Since then, Priuses in general have gotten cheaper (even for higher end models) and probably have better batteries, so the possibility of recovering the amortized marginal cost has gone up, although the mileage of the higher end models has gone down so the advantage isn't as great as well.

The problem with the whole electrical car issue is one of scaling. The electrical "car" that makes sense is the ELF (which is made in Durham where I live, curiously enough). It is basically a bike frame with bike tires. a SMALL (low weight) battery pack, a solar recharger on the roof, and enough of a "shell" to keep off rain and give you headlights and tail lights so you don't feel as vulnerable as you truly are driving them on the roadway with other cars around. Oh, and they have pedals and a gearing system that lets you smoothly draw on and mix human and battery power. They are pegged so they can't go over something like 25 mph so that one doesn't have to license them as a vehicle or have a driver's license to operate one. They don't require a kW-hour to travel one mile -- they use much less than this. Depending on how far away from work you live and how hilly the terrain, you can "drive" your ELF to and from work with or without pedaling, leave it in the sun all day, and recover just about as much energy as you burned from the battery on the round trip. A modest charger is all that is required to keep it charged up enough to maintain a range on the order of several tens of miles from ordinary 15 or 20 Amp household circuits in a reasonable amount of time.

Unfortunately, it just doesn't scale. You could remove the governor and add an extra high efficiency motor and an extra battery to get its speed up to (say) the 45-50 mph to make it move at the speed of traffic on the road I'd need to drive to get to work. You couldn't recharge it in a day any more with built in sunlight without adding a second or third panel and unfolding them when you left them and hoping they wouldn't be stolen, but charging would still be feasible. Of course then you'd be driving a narrow bike frame box with nylon cloth sides at 50 mph -- what could go wrong? Not to mention the scaling of the drag force/power and loss of range. You can't really load the vehicle with more than a few bags of groceries or a backpack or at most (for the larger model) a single human sitting in a precarious rumble seat, and I'm sure the extra load eats your range rapidly. But for urban/suburban transport at low speeds on roads with a really generous bike lane -- and you know how many of those there are -- or transport on dedicated roadways where time and being killed by other cars isn't an issue, they are gangbusters.

As for roadways that charge your cars, we might as well go with Heinlein's rolling roads or Tesla's giant MW scale power transmitters every couple of hundred feet, radiating most of that energy to the stars just so that we can use a tiny fraction wherever we are within its field. O.M.G.

And I'm certain that there are no negative biological effects associated with being a conductor with a substantial surface area passing over regions of roadway with huge, rapidly varying magnetic fields radiating power up under my ass. Or that eddy currents in the car's frame won't be an issue, gradually heating the car up much like the induction range that this scheme resembles. Or that a roadway of 100 kW coils operating synchronously on a GW power source will be completely robust against things like lightning or an EMP bomb set off by terrorists or disgruntled out of work gas station attendants. Or solar flares. Or...

Wake me up when somebody invents a battery that can be charged daily for 20 years without substantial loss in capacity, that can hold a mere 5 kW-hour/kg (putting it up there with ethanol, but not gasoline), and that costs around $1/kW-hour. Then one pays$20 up front for the energy storage equivalent of 1 gallon of pure ethanol fuel, $33 up front for the equivalent of a gallon of gasoline, in a similar total weight and even an advantage in volume. A "ten gallon tank" costs$330 and you are break even with regular gas tanks. Heck, go to $5/kW-hour --$1650 for the storage capacity of a 10 gallon gas tank would still be awesome. Now let's look at reality in the Tesla -- ooo, what's that? Around $500 per kW-hour?$45,000 for their battery, which still doesn't have anything like the range of a 10 gallon tank of gas?

Screw built in charging stations for the roadways. Even one order of magnitude improvement in the cost of high density batteries, forget improving their energy density would drop the cost for a 10 gallon tank equivalent to a mere $16,500, which means that the premium for an electric car would be no worse than that for a Prius. Unlike a Prius, they would still never break even in the foreseeable future -- you'd still have to pay something like 2x the cost of fuel as soon as people stop providing "free" charging stations. But the cost of Prius-like hybrids would fall substantially, and their hybrid efficiency would increase. ELF-like vehicles might open up at the low end -- a "safe" one person commute vehicle for less than$10,000 as opposed to a glorified closed frame electrobike.

This is the evil of this sort of thing. We'll spend millions researching an obvious boondoggle, instead of putting the money into one of the places that actually matter. One could spend 10 billion dollars equipping 100 miles of roadway with this, one could give all the people who drive the roadway the extra $20 or 30 thousand dollars worth of hardware per car needed to suck up the power, and somebody could improve the cost efficiency of batteries by an order of magnitude and waste 100% of your investment in an instant. Or come up with algae-produced biodiesel at a cost of$1/gallon, sustainable and scalable. Or build Mr. Fusion energy plants for cars. Or...

Like I said. IMO this is welfare work for scientists. That I can almost tolerate, even though the fermi estimate numbers above make the whole thing pretty obviously almost infinitely unlikely to ever be economically feasible at scale no matter how appealing they can make it sound in a grant proposal or sound bite. My one real fear is that this will sooner or later lead to a well-funded campaign pushed for and lobbied for by a small cabal of companies that stand to make a fortuned that convinces congress to drop that \$10 billion on converting some hapless piece of roadway, giving it its very own GW-scale power plant, huge transformers and capacitors all along the way, a hundred thousand dollars worth of electronics per meter of roadway, and some enormous incentive to get people to put pickups on the handful of cars that can actually use the power. Of the billions allocated, billions will magically make its way into the pockets of the lobbying companies, cost overruns will push billions to tens of billions, and we could have used all that money for something else! You know, something useful like eradicating venereal diseases, or educating small children or ending global poverty or hell, even building more solar power generation capability or improving solar cell cost efficiency, which has its own issues with amortization but at least can be a break-even proposition without any real subsidy in the near future.

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## Comment What an incredibly stupid idea... (Score 4, Insightful)77

... even with mod points to burn I can't resist weighing in on this one. Some ideas are just too dumb for words. Just what sort of energy efficiencies do they think that they are going to manage? Who is going to pay for this "free" (incredibly inefficient) energy? Just how much power will they have to deliver to even break even on a moving vehicle, and how much power will their "transmitter" have to radiate in order for the car's pickup to be able to receive enough power?

Shades of Nikolai Tesla! Why not just put up megawatt Tesla coils ever fifty meters and leave them on all the time! This is an idea that was proven stupid 100 years ago.

But hey, the government has lots of (my) money. I'll just try to think of it as scientific welfare, sort of like climate science. Too bad they aren't spending it on something that isn't quite so obviously a boondoggle, though.

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## Comment 7.2 mm a year... (Score 0)274

He had me right up to that point. But an assertion that one can measure the position of two kilometer scale objects many, many light years away to a precision OR accuracy of 1 cm (they claim a few THOUSANDTHS of a millimeter) is, frankly, incredible.

One guesses that they do no such thing -- instead they measure the temporal period of the orbit and infer the mutual radius on the basis of its slow shift. Our ability to slice time precisely is far greater than any angular resolution of an optical instrument, so I'm willing to believe that they observe a slow shift in orbital period. But then they aren't measuring orbital radius change to a precision of thousandths of millimeters, they are measuring orbital period, and further, they are assuming that gravitational radiation, which has yet to be directly observed and hence is still at best an attractive (pun intended) hypothesis, is the cause of the shift. But one could imagine other causes. The problem is that their inference begins to be built up out of an increasingly long tower of assumptions -- that (for example) the substantial tidal deformations of the stars as they orbit, the possibility of spin-orbit coupling, or interaction with further bodies unseen are responsible for the period shift and not just gravitational radiation. It always worries me when an experimentalist claims "99% agreement" with a theory in a measurement performed on something that far away -- my own experiences in more mundane research projects in earthly labs is that one almost never gets 99% agreement with a theory simple because it is difficult to measure all that must be measured precisely and accurately enough to get a number that precise.

There are exceptions, of course -- usually exceptions that arise after spending decades making a series of highly precise measurements in a carefully constrained environment, such as measurements of G or the electromagnetic couplings -- but I'd prefer a claim of consistency rather than proof of a theory in things like this, and would prefer it even more if the actual experimental result was announced, not the inference based on further assumptions that become additional Bayesian priors to the conclusion and that are not stated.

This isn't to defend alternatives to dark matter -- I have no dog in either fight -- only to point out that arguments for dark matter always end up being arguments against it being anything else. Of course this is the way it has to be -- dark matter is dark, an invisible fairy, which means that you can make it do anything without fear of refutation because, well, it is invisible. But it is spectacularly difficult to argue for a theory on the basis of null results for alternatives, simply because we may not have thought up the right alternatives yet. What is needed, of course, are direct observations of dark matter to put the matter to rest.

Darned invisible fairies, anyway! Maybe it hangs out in the same fairy bar with magnetic monopoles and Higgs bosons, although it is possible that Mr. Higgs has finally come out into the light of day.

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