What do you think space ship use as fuel? Gasoline?
Atlas: Kerosene and oxygen. Saturn V first stage: Kerosene and oxygen.
Arguably, many space ships do use gasoline. Kerosene isn't exactly gasoline, but it's very close and it all comes from oil. -- This post made from 100% post-consumer recycled magnetic
So they're going to drop a few hundred pounds of metal alloys on the Moon. Nature deposits tons of meteroids, some stony, some iron, some chondrites on the Moon every day. You can sift iron out of lunar regolith with nothing more sophisticated than a magnet; I don't think that human activity is going to be detectable on that scale until a few billion probes have crashed. -- This post made from 100% post-consumer recycled magnetic
Am I the only one who was more than a little stunned by the fact that China is ready to (or have they already done it?) put astronauts into space?
If you're stunned, you probably forgot that:
Manned spaceflight can be done with 40-year-old technology (American or Russian);
The Russians are in pretty bad economic shape and will do almost anything for money;
The Chinese have enough money to buy the technology to build the Soyuz.
Given that, it's a pretty small jump from having the will to having the hardware.
With the economy the way it is now, why the hell isn't someone working on finding new resources in space to propel us as a nation through the 21st century??? There's no telling if there's another "Seward's Folly" waiting out there for us.
What do you mean, "no telling"? OF COURSE they're out there, waiting (do you have any idea of the market value of just one medium-sized chunk of asteroidal nickel-iron?). It's just a matter of getting them back here at an affordable price. -- This post made from 100% post-consumer recycled magnetic
Rereading the company's website will lead you to notice that the spacecraft they have in mind will be designed to be disposable.
Of all the NASA spacecraft sent to other bodies in the last 30 years (Pioneers, Voyagers, Vikings, Mariners, Galileo, Cassini, Deep Space 1, Lunar Prospector, Mars Climate Orbiter, Mars Polar Lander...) can you name one that was not disposable? Unless you have some means of guaranteeing that the spacecraft can be returned to Earth (which is the only place where any kind of recycling or reuse infrastructure exists) there are exactly three possibilities: land on something (and probably never leave), crash into something (messily more likely than not) sooner or later, or continue in space indefinitely (as "junk").
The slightest amount of thought would have brought you to this conclusion yourself. So I've got to ask you, what was your point? -- This post made from 100% post-consumer recycled magnetic
Agreed, sadly. Doesn't this seem to be the norm of politics though? Placate the voters to vote for you again, and do the right thing when and if it's convenient - in that order.
<cynical>
No, the norm in politics is to tout the wrong thing as a solution to The Problem. This makes certain that The Problem will not be solved, and the organizations funded to address The Problem will not have to worry about working themselves out of jobs, nor will the constituencies built around The Problem have to find something else to do with their lives. It becomes a nice little pork-barrel project, creating a bunch of nice little sinecures which return support to the pol in a positive feedback loop.
Examples abound. Welfare subsidies were touted as a way to get rid of poverty (they didn't, and arguably created more); gun control is still touted as a way to get rid of crime (yet there have been surges in crime after every major gun-control measure); morals laws are touted as a way to get rid of prostitution (yet there are still prostitutes, and arguably the problem is worse with the twin scourges of crack cocaine and HIV).
Then there are the laws which merely support venality, like the forfeiture laws which allow the cops to keep whatever they take from you if they bust you for having certain controlled substances (whether you actually had any or not). But these don't actually increase the ill they purport to cure.
</cynical> -- This post made from 100% post-consumer recycled magnetic
How hard would it be for me to write a simple shell script... that finds all of the email addresses in a users pine/elm folders... and then mail a copy of the script to every one of those users and then execute a command such as "rm -rf *"
Oh, trivial. But how hard to get people to run it?
Definitely, much harder than with Outlook. Outlook runs the thing with a double-click (one click?). To do this under most Linux mailers, you'd have to:
Save the attachment.
Either
Change permissions on the resulting file to make it executable, or
Run the attachment by passing its name as an argument to a shell, e.g. "sh idiotscript".
The chances of most people doing all of this without stopping to think about what they're doing are a lot smaller than for just double-clicking. The virus depends on that behavior to propogate. Without a critical fraction of such people the average number of re-transmitters per batch falls below 1, and the virus dies.
The error made by Microsoft isn't that Windoze/Outlook is capable of doing such things, it's that it's so easy to do them without thinking... or even being asked about it (ala BubbleBoy). -- This post made from 100% post-consumer recycled magnetic
The mass media are finally, publicly, catching on: the problem with viruses is directly attributable to Micro$oft. Several items on the BBC news in the last couple of days make the same point; M$'s software design practices and "one-size-fits-all" lack of options (like having all scripting turned off by default, and activated only by the people who need it) leaves the entire Internet vulnerable to attacks like this. The actual damage might be limited to Windoze machines, but the mail storms deny service to the net as a whole.
And most important, the media are beginning to say so, out loud.
When the media take notice, the technically-clueless CEO's will be right behind. Soon, IT managers will be fired for failing to convert to more-reliable, less-vulnerable mail clients and network servers. This is the beginning of the end of Microsoft as we know it. -- This post made from 100% post-consumer recycled magnetic
How about this: The equipment needed to recycle spent nuclear fuel for reuse in power plants can also be used for enriching Plutonium for use in nuclear weapons.
That doesn't explain why private companies in the USA (where the NRC can verify that nothing untoward is going on) are forbidden from reprocessing spent nuclear fuel, period.
If you can run a research reactor, you can breed fissile U-233 from Thorium-232. You don't need more than a chemistry lab to separate the two. If you have gas centrifuges, you don't need to breed anything; you can separate bomb-grade U-235 from natural uranium. The ban on reprocessing may have been politically expedient (because it plays well to an ignorant public), but it has next to zero scientific foundation. -- This post made from 100% post-consumer recycled magnetic
Science Fiction is usually (with few exceptions - Samuel Delany comes to mind) no better than other forms of pulp and is only accepted because of its subject.
Many, many years ago, a famous duo was conversing over... something. (You know this was many years ago because both of the participants are dead, likely before you were born.) The exchange was related to go something like this:
John W. Campbell: "Ted, ninety percent of the stuff that's called science fiction is crap."
Theodore Sturgeon: "John, ninety percent of everything is crap."
Thus we have Sturgeon's Law, "Ninety percent of everything is crap". (Theodore Sturgeon was a science fiction author of some note, and John W. Campbell was both an author and long-time editor of Amazing Stories, which is now Analog, the hardest of the hard-SF available in a monthly magazine. Ironically, JWC was one of the people taken in by the Dean Drive hoax.) -- This post made from 100% post-consumer recycled magnetic
The reason there is radio-active waste is NRC regulation, since 'recycling' waste results in weapons-grade nuclear fuel.
No, it doesn't.
Recycling spent fuel from PWR's, with their typical burnup of 40,000 to 50,000 megawatt-days per ton, yields a fair amount of plutonium. Problem for the weapons business is, all Pu is not created equal. The isotope of interest is Pu-239, which is both fissile and has a reasonably low rate of spontaneous fissions. (Too high a rate of SF's, and you can't assemble a supercritical mass before it disassembles itself; once it's expanded past the point where it is prompt-supercritical it stops yielding energy, even if it's only given you the equivalent of a few kg of TNT. To get that supercritical mass, you have to delay the onset of the chain reaction until the fissile material is sufficiently compressed to give a good yield. ONE spontaneous fission in the mean time....)
Bomb-grade material is not made in power reactors. It is (was, in the USA; we're not making any more) made in special reactors from depleted uranium (DU) rods, which are irradiated for a very short time and then processed to remove the plutonium. A short period of irradiation creates some Pu-239, but doesn't allow very much of the Pu-239 to be transmuted to the problematic (very high SF rate) isotopes of Pu-240 and Pu-241. In a power reactor you just plain don't care about the spontaneous fission rate, but for a bomb it is crucial. The spontaneous fission rate of the plutonium from power reactors is way beyond anything that a bomb designer would even think of using. And that's why commercial nuclear power is not a bomb-proliferation risk even with reprocessing (the political posturing over plutonium notwithstanding), and why story lines based on this are technically deficient. AAMOF, any story which treats this falsehood as a given should probably not be called science fiction. -- This post made from 100% post-consumer recycled magnetic
In a way, a scientific background can be a limitation. It forces you to always do the logical next step. Someone without a scientific background on the other hand, might come up with an idea thats totally ridiculous at first to any scientist, but thats revolutionary enough to be worth trying to implement anyway.
You're wrong, several times over.
There's no such thing as a "logical next step", as you think of it, in science. Most science gets done by looking at something that nobody's looked at before. The only "logical next steps" involve cross-checking and confirming that you really have what you think you have.
Someone without a scientific background is going to be unable to spot the mistakes which permanently place a concept in the realm of utter fantasy... or at least until someone discovers exceptions to certain laws of physics or reduces magic to engineering-level practicality.
"Totally ridiculous to a scientist" means that the idea violates one or more of the laws of conservation of energy, momentum, angular momentum, charge, baryon number, or the like. If it doesn't try breaking one of those, and it looks like it can be done with existing materials, you might have something.
"Revolutionary enough to be worth trying to implement anyway", like employing a bunch of people sitting in a bunker focussing their thoughts trying to psychically ferret their way into the minds of the nation's strategic enemies? Oops, we actually did try that. It was another one of the things that had no basis in known physics, and guess what... it didn't work!
The true scientist, the person who knows the constraints imposed by natural law, is always going to have the advantage when rating these wild-assed guesses, and even more of an advantage when trying to come up with new ones. The ignoramus is usually going to come up with schemes on the order of "If we made flying pigs, we could have them poop on our enemies and defeat them"; never mind that no flying animal has ever been as heavy as a full-grown pig. The thinker with the solid grounding in science knows the limitations, and by implication, the places where they don't apply. Genetically engineering English sparrows to poop like pigs upon our enemies, and thus defeat them, isn't forbidden by physical law.
This is borne out by history. The Dean Drive, an "inertialess propulsion" system based on reciprocating masses, was a complete failure. None of the various "free energy" concepts making the rounds has ever had a successful test under controlled conditions. On the other hand, there are ion engines, photon sails, and other ideas which are based firmly on the existing physical laws as they are currently understood, and mirabile dictu - they work!
Go ahead and try to dream up some miracle space-flight device. Spend all of your life on it, if you like. If you don't bother to get a good understanding of the physics which rules the regime in which your device must operate, you have a 99.9999% chance of completely wasting your time... and also the time of anyone who listens to you talk about it. And that's why scientists usually blow off the "miracle" schemes of the ignorant: it wastes their time, which they could use to make progress on something that will actually work. There are so many ignoramuses out there with unworkable "miracle" ideas that if scientists gave their ears to a significant number of them, science itself would grind to a halt.
So do the whole world a favor. Get yourself a physics textbook and don't bother posting on a topic like this until you understand all the material forwards and backwards. I mean, know it cold. All the laws of statics, kinetics, electromagnetics, thermodynamics... all of it. Then you'll see where your errors were. You'll also be in a really good position to contribute to real progress.
See you in ten years? -- This post made from 100% post-consumer recycled magnetic
Wow, that was an amazingly long article considering it was essentially made up of questionable quotes from a couple of different sources and large amounts of speculation.
After reading that article, I got the impression that there was a lot of confusion going around, that the Mozilla people hadn't made themselves totally clear, and that there were a lot of other people who were VERY CONCERNED about what this action, or lack thereof, might portend.
This is also a chance for the public, or the/. fraction thereof, to give feedback to Mozilla. You're getting it. Here's my two cents: We ABSOLUTELY want an end to abusive banner ads and surfer surveillance, and we want at least some of these user-protection features built into our browser instead of having to hang on an external proxy filter. Capisce? -- This post made from 100% post-consumer recycled magnetic
A few years ago, I made a $16 purchase in a supermarket. I gave a $20 to the assistant manager (!) working the register. He rang it up as $200, and started counting out the $184 the machine told him to give me.
You beg the question: Did you punish the idiot by letting him leave his drawer $180 short, or did you save his incompetent bacon so he could bestow bonuses on others without the arithmetic knowledge to realize that he was wrong?
This isn't a serious question, but more of a social quandary; should we let these people continue to screw things up in the world at large, or force them into remedial education as soon as humanly possible to try to arrest, or at least slow, the damage? -- This post made from 100% post-consumer recycled magnetic
I once heard a quote from a mathematician (IIRC he was a professor somewhere). He basically said that most people will not use much more than basic arithmetic (say 6th grade level) in their lives.
Very interesting, indeed. I must be one hell of an outlier, because I found myself using differential calculus on a summer job between my junior and senior years, to calculate the optimum diameter of a circular weight for balancing a roller. It had to fit inside a cylindrical envelope (the diameter of the roller), of course. I found that the circular weight of minimum thickness was 2/3 the diameter of the roller (it would have gone past the shaft, clearly impractical) but that told me something very useful. I was actually subtracting mass by drilling instead of adding mass, but that's another story.
There are so many important things in everyone's lives which really require algebra or better that it's sad most people can barely handle arithmetic. For instance, the optimum first-year depreciation deduction for a business vehicle may not be either the flat deduction or the straight-line or double-declining balance figure, but some proportion of one and the balance of the other to reach the depreciation limit. To determine what the proportions should be, you need algebra and differential calculus. It's a simple formula, but you need to understand what you are doing. Another example is home mortgages and retirement planning. If you don't know what your loan balance will be 5 years from now, you have no way to plan. If you can't calculate your IRA portfolio's value based on projected rates of return, and the income you can expect to take from it, you have no idea what you have available to live on and what kind of lifestyle you can expect... nor what to do to get to where you want to be. This requires knowledge of compound interest, which is a fairly simple derivative of the formula for the sum of an infinite series.
This last is very important in politics. A great debate is going on in the US presidential race, and it is almost entirely uninformed by numbers. Only a tiny fraction of the populace would understand, so the news media does not publish them, and ignorance is perpetuated. This certainly does not serve either the body politic or posterity.
Algebra and calculus would be useful to a huge number of people, far more than have a good command of them. Unfortunately, those who have the need for it often have no idea what their problem is or that some knowledge of these matters would improve their lives. -- This post made from 100% post-consumer recycled magnetic
The CIO of the Fortune 50 company for whom I work issued a memo to all employees that no Open Source would be used on any system in any manner.
However, we did not immediately disable all systems company-wide and shut the whole thing down to remove the many Unix-standard tools that happen to be Open Source, and that run standard system services on every single Unix machine in the entire company. We just ignored him.
It would have been ethical to do what he asked, after making it abundantly clear to him (and the CEO) exactly what the consequences would be. A memo, delivered both electronically and by hard-copy, to the CEO (and CFO), with a copy of the CIO's original memo attached, would be a serious wake-up call. With any luck, you could convince the CEO and CFO in one fell swoop that the CIO is dangerously incompetent and ought not to be part of the company any longer.
Now wouldn't that have been nice? -- This post made from 100% post-consumer recycled magnetic
...the barcode reader would add the personalised code in software...
But without individualization of each copy of the magazine and its bar codes, the publisher cannot tell which copy a person is scanning, and thus cannot tell how many people have read that specific copy. That would be essential for implementing an individual/business subscription rate differential. -- This post made from 100% post-consumer recycled magnetic
With some exceptions (really metal-rich asteroids, like ones formed from the nickel-iron cores of their parent bodies, excepted) lots of asteroids seem to be "rubble piles", loosely aggregated heaps of debris held together only by their gravitational attraction. This also gives them protection against being shattered by impacts; the spaces between the pieces just reflect and absorb the shocks, leaving a slightly different configuration of the chunks.
From the JPL pictures, it appears to rotate end-over-end, which could provide some gravity from angular acceleration. The middle portion would be great for zero-g laboratories.
If the object was spinning faster than the speed of an object in orbit around it, there wouldn't be any loose material on its surface (it would have flown off into space). Even if there was a solid chunk of nickel-iron forming the core, you probably wouldn't want to try spinning the whole body fast enough to give you significant G's even if you had the ability; would you trust your welfare to a single piece of an unknown alloy with who-knows-what kind of damage and stress history? One crack growing from a trace flaw....
On the other hand, if the layer of loose stuff on the surface is thick enough, you could just dig a trench in it big enough to spin a wheel-type space station built of nickel-iron pipe (if it's metal-rich, you should have plenty to play with). Unless you want to hollow out a whole disk you have to forget about spokes... then you put a lid on the trench with enough clearance for a bit of wobble and cover it with the material you removed, forming a cosmic-ray shield. Spin up the wheel, artificial gravity. -- This post made from 100% post-consumer recycled magnetic
Unfortunately it is impossible for a massless particle to reach the speed of light...
Au contraire. It is only possible for a massless particle to exist at the speed of light! A particle with mass (that is, rest mass) can never get to the speed of light. -- This post made from 100% post-consumer recycled magnetic
The point is, none of us were there to observe the beginning of the universe, and it cannot be repeated(by us) so it CANNOT be scientifically studied.
Nobody alive today was there to see the events in the Bible, so why don't you apply the same skepticism to them as you apply to the results of the scientific method applied to rock stratigraphy, fossil data, radioisotope dating, astrophysics, the expansion of the universe and the cosmic background radiation....
All you have to do to accept a 12 billion year-old universe, a 4.3 billion year old Earth, and all that is to assume that God is not malicious and wouldn't play fast and loose with physical laws and other evidence so as to make the world appear to be something it is not. Why would you believe in a God who lies with His creation, anyway? Sounds more like the other guy. -- This post made from 100% post-consumer recycled magnetic
The cool thing to do is to maximize drag and get rid of the thrust altogether. Then you have a magnetic solar sail.
While you're thinking about that, look at the speeds typical of the interstellar and intergalactic gas flows. Those flows are probably falling into the galaxies by now. You're not going to go fast, and you're not going to get far.
You're better off with antimatter-driven rockets, laser-driven lightsails, or the like. With a proton-antiproton annihilation drive (they annihilate to 3 pi-mesons, of which two are charged and can be directed with a magnetic nozzle) you can go between Sol and Alpha Centauri in about a year ship-time (given enough fuel, of course). Using a microwave sail (Star Wisp) you could accelerate a tiny probe at hundreds of G's with a microwave beam and get it to a healthy fraction of c before leaving the solar system; this would get you data from the vicinity of other stars before the end of your academic career. Magsails and such would be great for getting around the Solar System, but utterly useless for travel between stars. -- This post made from 100% post-consumer recycled magnetic
If you haven't read the article all the way through, you probably missed this related piece. A quote:
Digimarc's technology also uses images to store information but takes a different approach. Its digital watermarks are designed not to be perceptible to the human eye...
Imagine, for example, a photograph on a magazine page. Before the magazine is printed, the watermark is applied to an electronic version of the photograph by using Digimarc's production software. When printed, the photograph may look no different at first glance, but in fact the pixels have been adjusted to contain tiny signals that can be picked up by a digital camera that includes Digimarc software. The technology adjusts the luminance of the pixels, which a trained eye might pick up as a slight variation in an image's color or shades of light and dark.
In a matter of a couple of years, steganography has gone from a way of frustrating the police-state forces who want to ban cryptography, to a way of delivering information and hyper-references to a reader via a piece of paper. -- This post made from 100% post-consumer recycled magnetic
Slashdot Mirror
Saturn V first stage: Kerosene and oxygen.
Arguably, many space ships do use gasoline. Kerosene isn't exactly gasoline, but it's very close and it all comes from oil.
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CH4 + 2 H20 -> CO2 + 4H2
The methane is typically obtained from fossil fuel.
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So they're going to drop a few hundred pounds of metal alloys on the Moon. Nature deposits tons of meteroids, some stony, some iron, some chondrites on the Moon every day. You can sift iron out of lunar regolith with nothing more sophisticated than a magnet; I don't think that human activity is going to be detectable on that scale until a few billion probes have crashed.
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- Manned spaceflight can be done with 40-year-old technology (American or Russian);
- The Russians are in pretty bad economic shape and will do almost anything for money;
- The Chinese have enough money to buy the technology to build the Soyuz.
Given that, it's a pretty small jump from having the will to having the hardware. What do you mean, "no telling"? OF COURSE they're out there, waiting (do you have any idea of the market value of just one medium-sized chunk of asteroidal nickel-iron?). It's just a matter of getting them back here at an affordable price.--
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The slightest amount of thought would have brought you to this conclusion yourself. So I've got to ask you, what was your point?
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Snaggy, there IS such a thing as too much self-promotion.
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No, the norm in politics is to tout the wrong thing as a solution to The Problem. This makes certain that The Problem will not be solved, and the organizations funded to address The Problem will not have to worry about working themselves out of jobs, nor will the constituencies built around The Problem have to find something else to do with their lives. It becomes a nice little pork-barrel project, creating a bunch of nice little sinecures which return support to the pol in a positive feedback loop.
Examples abound. Welfare subsidies were touted as a way to get rid of poverty (they didn't, and arguably created more); gun control is still touted as a way to get rid of crime (yet there have been surges in crime after every major gun-control measure); morals laws are touted as a way to get rid of prostitution (yet there are still prostitutes, and arguably the problem is worse with the twin scourges of crack cocaine and HIV).
Then there are the laws which merely support venality, like the forfeiture laws which allow the cops to keep whatever they take from you if they bust you for having certain controlled substances (whether you actually had any or not). But these don't actually increase the ill they purport to cure.
</cynical>
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I about fell over laughing when I read that...
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Definitely, much harder than with Outlook. Outlook runs the thing with a double-click (one click?). To do this under most Linux mailers, you'd have to:
- Save the attachment.
- Either
- Change permissions on the resulting file to make it executable, or
- Run the attachment by passing its name as an argument to a shell, e.g. "sh idiotscript".
The chances of most people doing all of this without stopping to think about what they're doing are a lot smaller than for just double-clicking. The virus depends on that behavior to propogate. Without a critical fraction of such people the average number of re-transmitters per batch falls below 1, and the virus dies.The error made by Microsoft isn't that Windoze/Outlook is capable of doing such things, it's that it's so easy to do them without thinking... or even being asked about it (ala BubbleBoy).
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And most important, the media are beginning to say so, out loud.
When the media take notice, the technically-clueless CEO's will be right behind. Soon, IT managers will be fired for failing to convert to more-reliable, less-vulnerable mail clients and network servers. This is the beginning of the end of Microsoft as we know it.
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If you can run a research reactor, you can breed fissile U-233 from Thorium-232. You don't need more than a chemistry lab to separate the two. If you have gas centrifuges, you don't need to breed anything; you can separate bomb-grade U-235 from natural uranium. The ban on reprocessing may have been politically expedient (because it plays well to an ignorant public), but it has next to zero scientific foundation.
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John W. Campbell: "Ted, ninety percent of the stuff that's called science fiction is crap."
Theodore Sturgeon: "John, ninety percent of everything is crap."
Thus we have Sturgeon's Law, "Ninety percent of everything is crap". (Theodore Sturgeon was a science fiction author of some note, and John W. Campbell was both an author and long-time editor of Amazing Stories, which is now Analog, the hardest of the hard-SF available in a monthly magazine. Ironically, JWC was one of the people taken in by the Dean Drive hoax.)
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They'd probably just nuke you from orbit, because it's the only way to be sure.
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Recycling spent fuel from PWR's, with their typical burnup of 40,000 to 50,000 megawatt-days per ton, yields a fair amount of plutonium. Problem for the weapons business is, all Pu is not created equal. The isotope of interest is Pu-239, which is both fissile and has a reasonably low rate of spontaneous fissions. (Too high a rate of SF's, and you can't assemble a supercritical mass before it disassembles itself; once it's expanded past the point where it is prompt-supercritical it stops yielding energy, even if it's only given you the equivalent of a few kg of TNT. To get that supercritical mass, you have to delay the onset of the chain reaction until the fissile material is sufficiently compressed to give a good yield. ONE spontaneous fission in the mean time....)
Bomb-grade material is not made in power reactors. It is (was, in the USA; we're not making any more) made in special reactors from depleted uranium (DU) rods, which are irradiated for a very short time and then processed to remove the plutonium. A short period of irradiation creates some Pu-239, but doesn't allow very much of the Pu-239 to be transmuted to the problematic (very high SF rate) isotopes of Pu-240 and Pu-241. In a power reactor you just plain don't care about the spontaneous fission rate, but for a bomb it is crucial. The spontaneous fission rate of the plutonium from power reactors is way beyond anything that a bomb designer would even think of using. And that's why commercial nuclear power is not a bomb-proliferation risk even with reprocessing (the political posturing over plutonium notwithstanding), and why story lines based on this are technically deficient. AAMOF, any story which treats this falsehood as a given should probably not be called science fiction.
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- There's no such thing as a "logical next step", as you think of it, in science. Most science gets done by looking at something that nobody's looked at before. The only "logical next steps" involve cross-checking and confirming that you really have what you think you have.
- Someone without a scientific background is going to be unable to spot the mistakes which permanently place a concept in the realm of utter fantasy... or at least until someone discovers exceptions to certain laws of physics or reduces magic to engineering-level practicality.
- "Totally ridiculous to a scientist" means that the idea violates one or more of the laws of conservation of energy, momentum, angular momentum, charge, baryon number, or the like. If it doesn't try breaking one of those, and it looks like it can be done with existing materials, you might have something.
- "Revolutionary enough to be worth trying to implement anyway", like employing a bunch of people sitting in a bunker focussing their thoughts trying to psychically ferret their way into the minds of the nation's strategic enemies? Oops, we actually did try that. It was another one of the things that had no basis in known physics, and guess what... it didn't work!
The true scientist, the person who knows the constraints imposed by natural law, is always going to have the advantage when rating these wild-assed guesses, and even more of an advantage when trying to come up with new ones. The ignoramus is usually going to come up with schemes on the order of "If we made flying pigs, we could have them poop on our enemies and defeat them"; never mind that no flying animal has ever been as heavy as a full-grown pig. The thinker with the solid grounding in science knows the limitations, and by implication, the places where they don't apply. Genetically engineering English sparrows to poop like pigs upon our enemies, and thus defeat them, isn't forbidden by physical law.This is borne out by history. The Dean Drive, an "inertialess propulsion" system based on reciprocating masses, was a complete failure. None of the various "free energy" concepts making the rounds has ever had a successful test under controlled conditions. On the other hand, there are ion engines, photon sails, and other ideas which are based firmly on the existing physical laws as they are currently understood, and mirabile dictu - they work!
Go ahead and try to dream up some miracle space-flight device. Spend all of your life on it, if you like. If you don't bother to get a good understanding of the physics which rules the regime in which your device must operate, you have a 99.9999% chance of completely wasting your time... and also the time of anyone who listens to you talk about it. And that's why scientists usually blow off the "miracle" schemes of the ignorant: it wastes their time, which they could use to make progress on something that will actually work. There are so many ignoramuses out there with unworkable "miracle" ideas that if scientists gave their ears to a significant number of them, science itself would grind to a halt.
So do the whole world a favor. Get yourself a physics textbook and don't bother posting on a topic like this until you understand all the material forwards and backwards. I mean, know it cold. All the laws of statics, kinetics, electromagnetics, thermodynamics... all of it. Then you'll see where your errors were. You'll also be in a really good position to contribute to real progress.
See you in ten years?
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This is also a chance for the public, or the /. fraction thereof, to give feedback to Mozilla. You're getting it. Here's my two cents: We ABSOLUTELY want an end to abusive banner ads and surfer surveillance, and we want at least some of these user-protection features built into our browser instead of having to hang on an external proxy filter. Capisce?
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This isn't a serious question, but more of a social quandary; should we let these people continue to screw things up in the world at large, or force them into remedial education as soon as humanly possible to try to arrest, or at least slow, the damage?
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There are so many important things in everyone's lives which really require algebra or better that it's sad most people can barely handle arithmetic. For instance, the optimum first-year depreciation deduction for a business vehicle may not be either the flat deduction or the straight-line or double-declining balance figure, but some proportion of one and the balance of the other to reach the depreciation limit. To determine what the proportions should be, you need algebra and differential calculus. It's a simple formula, but you need to understand what you are doing. Another example is home mortgages and retirement planning. If you don't know what your loan balance will be 5 years from now, you have no way to plan. If you can't calculate your IRA portfolio's value based on projected rates of return, and the income you can expect to take from it, you have no idea what you have available to live on and what kind of lifestyle you can expect... nor what to do to get to where you want to be. This requires knowledge of compound interest, which is a fairly simple derivative of the formula for the sum of an infinite series.
This last is very important in politics. A great debate is going on in the US presidential race, and it is almost entirely uninformed by numbers. Only a tiny fraction of the populace would understand, so the news media does not publish them, and ignorance is perpetuated. This certainly does not serve either the body politic or posterity.
Algebra and calculus would be useful to a huge number of people, far more than have a good command of them. Unfortunately, those who have the need for it often have no idea what their problem is or that some knowledge of these matters would improve their lives.
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Now wouldn't that have been nice?
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On the other hand, if the layer of loose stuff on the surface is thick enough, you could just dig a trench in it big enough to spin a wheel-type space station built of nickel-iron pipe (if it's metal-rich, you should have plenty to play with). Unless you want to hollow out a whole disk you have to forget about spokes... then you put a lid on the trench with enough clearance for a bit of wobble and cover it with the material you removed, forming a cosmic-ray shield. Spin up the wheel, artificial gravity.
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All you have to do to accept a 12 billion year-old universe, a 4.3 billion year old Earth, and all that is to assume that God is not malicious and wouldn't play fast and loose with physical laws and other evidence so as to make the world appear to be something it is not. Why would you believe in a God who lies with His creation, anyway? Sounds more like the other guy.
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You're better off with antimatter-driven rockets, laser-driven lightsails, or the like. With a proton-antiproton annihilation drive (they annihilate to 3 pi-mesons, of which two are charged and can be directed with a magnetic nozzle) you can go between Sol and Alpha Centauri in about a year ship-time (given enough fuel, of course). Using a microwave sail (Star Wisp) you could accelerate a tiny probe at hundreds of G's with a microwave beam and get it to a healthy fraction of c before leaving the solar system; this would get you data from the vicinity of other stars before the end of your academic career. Magsails and such would be great for getting around the Solar System, but utterly useless for travel between stars.
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