I have mixed feelings about this. I am from Sweden, and it always looks kind of ugly when names lose their dots and circles in the domain name.
On the other hand, this is also quite convenient. I live in the US now, and I travel around quite a bit. I often surf on Swedish Internet sites, typically without access to a Swedish keyboard. It would not be very convenient if the domain names used non-English symbols.
Sometimes I go to Japanese sites also, and I am really glad that I don't have to install a Japanese word processor to do this...
One thing I'm not clear about when we're talking about sub-atomic particles - how do we know we've got it right?
As far as scientists are concerned, they got it right when they make predictions that are verified by experiments. Period. Whether it is "true" or a "misleading abstraction" is for the philosophers and the priests to sort out.
In this case, they did not get it right because the new particle was not predicted. This has lead to new hypothesis such as a 4-quark particle. If such an hypothesis acurately predicts the outcome of additional experiements, then it is right enough for the scientists. Some philosophers and the priests may disagree but at least they have to concede that the scientific hypothesis was useful - it predicted a novel phenomenon.
At any rate, natural evolution proceeds at a slow rate, so the defending species has time to adapt.
Natural evolution is not slow for viruses; their genetic code does not have the copy-protection mechanisms of say mammals. That is why we have a new flu pop up every other year, or a SARS for that matter.
Anthrax, for example, implements a tricky chemical hack to breach animal cells and destroy them. Most animals are pretty defenseless against the special back door that antrax uses, and without it the anthrax bacteria would be no more harmful than a pimple. However, anthrax is a rather obscure organism that mostly lives in the dirt. The reason that animals haven't evolved a defense against its chemical attack is that it just doesn't spread that easily in a natural setting. If anthrax were contagious like a cold, animals would have evolved a defense against it long ago.
With all due respect I think you are contradicting yourself. When a patheogen spreads for natural or not so natural reasons, people may die. Some survive, the resistant genes thus become more common. There may even be mutations of strong resistance that start to spread.
When this process happens for natural reasons, you label it "evolving a defense", or "defending species having time to adapt". When it happens by an act of man, you think of it as man being caught "defenseless". Of course, in both cases the species start out as (relatively) defenseless, and end up with a better defense.
My whole point was that there seem to be no lab-made pahtogen worse than anything evolved in nature. As for spreading it by man, well, anthrax did get an assist by man. But the extent of that "outbreak" was miniscule next to the natural outbreaks that happen every year.
Unless somebody figures out how to make an artificial microbe that takes advantage of chemical processes that just aren't found in natural evolution. For example, the human body might not even be capable of attacking a hypothetical microbe that has a teflon or silicone-enhanced outer membrane.
Possibly. But then again, if such mechanisms were very successful, why did they not evolve for 4 billion years on a planet surface covered in silicon compounds. In general, it is very difficult for people in labs to compete with the lab which is our planet, and time-scales of millions or billions of years.
I'm not a luddite and not really affraid this new virus is going to do something horrible like download copyright music from the RIAA. But what makes this new man-made virus any less capable of mutating or evolving than any other virus?
Probably nothing. But my point was not that we should not be careful. My point was that there should be no need to be significantly more careful than we are with other viruses.
The original post questioned whether "we really should be doing this". My response is: are you equally concerned by the everyday handling of viruses in thousands of research labs? Why not?
Technically it's not life. There is still a bit of dispute as to whether virused are alive or not. They contain genetic material, but are not necessarily living organisms. Or that is what some bio major told me once.
Whether virus is life or not depends on the definition of life. There is no consensus on this defintion, so debates on the matter are rather meaningless, it is really disputes over the definition of a word.
What makes viruses controversial is that they cannot reproduce by themselves; they need to infect antoher cell. But then again, many parasites cannot live without some other organism, and they are usuually considered alive.
Which is perfectly reasonable. People seem to be exremely afraid of anything made in a lab, but fail to recognize that the greater danger (by far) is from natural evolution of new viruses.
By the same token, the dangers of bio-weapons seem to be greatly excaggerated, when compared to natural pathogens. Some anthrax letters that killed half a dozen people seemed to get more attention and resources than the flu and aids, which kill tens of thousands of people per year in the US alone.
I'm Canadian. I love 2 hours away from the United States.
And take my word for it, there is NOBODY here who envies the United States. Pity might be a better word.
My point was not that the US is the center of the universe. Rather I wished to point out the contradiction in the original post. How can one expect the US to provide music downloading for the world, and at the same time be angry because the US think it is great?
Good for you to be so happy in Canada. Of course your hapiness is not uncommon; anthopologists are well aware that citizens of virtually all societies (including the US, Canada, and the most primitive stone-age tribes in Africa) are convinved that their own society is the best in the world.
As it stands, when things like this happen, it just demonstrates that the United States still thinks that it's the center of the Universe. Grrr.
And what proves that the US is right is the fact that Europe does not simply construct their own system, but rather directs its energy to anger and envy towards the US.
Probably? Assuredly, I would say. If transistor count continues to double every 2 years, with 42M transistors per CPU in 2000, you would have 43 billion in 2010, 44 trillion in 2020, 47*10^21 in 2050, and 53*10^36 in 2100. If that hasn't reached the number of atoms in the known universe, then keep counting years and it will.
The number of atoms in the universe is not the limit for computation. The true limit is set by quantum states. It is actually possible to caluclate these limits, Professor Seth Lloyd at MIT calculated how much computation can possibly come out of 1kg of matter confined to a volume of 1l - "the ultimate laptop". And yes, if Moore's law keeps going then we will be there in a few hundered years. Of course, it could be argued that we will never get there in pracitce. On the other hand, current quantum computers are nearly optimal in this regard - unfortunately they only contain a few atoms or so...
I would think the author would go back to at least 2,000 BCE or even 10,000 and identify the collosal leap made in farming. For a species to go from forraging to agrigulture seems like an enormous effort of overlapping memes (and luck).
1. Agriculture developed independently on many places of the planet.
2. The purpose of the study was not to have a cool ranking list but to identify how society and institutions should be run to foster innovation in various fields. It seems unlikely that trying to squize in some patchy data from the stone age would help achieving that goal.
Preventing roll-overs: Buy a car that's not top-heavy. If you have a real need for an SUV that is top-heavy, don't try to drive it like a car, because it's not. It's a truck, and you should be aware of that (ie, avoid turning sharply, braking suddenly, etc). The newer cross-over and car-based SUVs (Chrysler Pacifica, Porsche Cayenne/VW Touareg, Infiniti FX models, etc) are much better in this respect. I'm referring mostly to the body-on-frame truck-based SUVs. I don't drive my huge F250 like I do my Boxster, simply because the F250 doesn't handle like the Boxster does.
You seem to have missed that this is a race through a desert, partly off-road. The vehicles of choice will probably be hummers and buggys, and even these will flip if pushed too hard.
have a crappy knife, a crappy magnifying glass, a crappy saw, crappy tweezers... but their business has been going gangbusters for decades. So I'd say you're not necessarily a dying breed, there has always been a market for "do everything, crappily
And the reason for this market is that when you are out camping, it is not so convenient to put a great knife, a great magnifying glass, a great saw and a great set of tweezers in your pocket.
Similarly, I find it inconvenient to always carry around a camera, a PDA and a cellphone. I think I will get one of these things when they get a bit cheaper. I realize that the camera will not be a Hasselblad but on the other hand I will always have access to it.
Seriously though, this brings back the same question as posed on last Monday, in this article: Death of the PDA?
For me, the key problem, which seems hard to engineer around, is this:
1)I would like the device to be so small that I can put it in my pocket
2)I would like the display to be bigger than would fit in my pocket.
Even if the device has both a phone and a to-do list it can only do either 1) or 2) for me, not both. Those that only do 1) we can call cell phones and those that can only do 2) PDAs. This new Sony Ericsson seems to be somewhere in between; display on the small side (for a PDA) and uncomfortable in a pocket (compared to a cell phone)...
What's wrong with a working business model that's paid for by taxpayers?
The roads you're so fond of driving your climate-changing SUV are working under a business model that's heavily paid for by taxpayers, boy.
Why on earth should tax payers subsidize concorde travel, a luxery goods enjoyed by a priviledged few?
I hate driving and I don't have a car, let alone an SUV. I would be all in favor for reducing government spending on roads. Although admitevly, economic theory does lend some support for tax supported basic infrastructure (free-rider-problem). The same can not be said about concorde travel.
.Hopefully there is a concorde II with the following improvements:
1. A glass cockpit instead of the analog crap in the old concorde
2. More efficient turbofan engines instead of the gas-guzzling turbojets on the Concorde.
3. A more roomy cabin
4. A working business model / not paid for by taxpayers
But back around 1900 or so, the Supreme Court managed to grant the rights of personhood to corporations.
So there is precedent for granting rights to non-humans, though corporations are 'assemblies of humans.' But assuming a true AI has been built/programmed by humans, I guess it could be considered an 'assembly of humans,' too.
It is quite self-evident that assemblies of humans must have the rights of individual humans. What is the alternative? To prevent you and your friends from making a joint statement or joint decision, or from cooperate in your pursuit of happiness? The only significant right a corporation has that a group cooperating humans does not is that if the cooperation goes belly up, the lenders cannot take the personal money from the share holders. If you are uncomfortable with this right then you are perfectly free never to lend your money to a corporation and thus not expose yourself to such a risk.
But the corporation is still under control of humans, specifically in proportion to their ownership of stock. It can be terminated by those owners. Similarly, an AI can be terminated by its owner by current legislation, and the morality of this is what is being questioned.
Sure, they may lose/ piss off customers but they really don't have an alternative business model.
Their business is to distribute music; and guess what, that can be done for dirt cheap by anyone now. It is to be expected that RIAA will fight to the bitter end.
I only hope that more artists realize this as well...
A lot of the course notes aren't particularly useful without a teacher actually explaining things to you. For example, look at the following link .
While some of the notes may be useful and educational, I don't think it replaces a real, live professor explaning things and available to answer questions.
1. I don't think anybody was suggesting that this should replace real profs at MIT. This is extra resources for people outside of universities, who don't have the option of talking to a prof.
2 Personally, I actually disagree with your point. I have found that I learn the most reading and solving problems, not when I listen to somebody talking (especially not in the big lecture format).
In other words: the maximum push of ion engine is only limited by the energy source and technical competence in high-voltage engineering, not by any inherent flaw in the technology. An ion engine is perfectly capable of lifting from Earth surface (or chasing X-Wings) assuming you have a suitable power source (nuclear reactor, most likely) and power trasporting/transforming equipment (wires and a voltage converter).
This is very true, but
1 All ion engines currently discussed use solar cells as their energy source. The whole point is that you only bring matter, not the energy source to accelerate it.
2 If you are prepared to bring an energy source as well, then you are basically back to the rocket case. Sure, you can bring a nuclear reactor, use heated atoms to drive a turbine and generate electricity, and then use the electricity to accellerate ions. But then it is more efficient to use your reactor to throw out particles directly, skipping the step of turbines and electricity generation. Btw researchers are working on such nuclear rocket systems. These would be much more efficient than anything we have today, but also politically problematic to say the least.
Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.
All means of propulsion -on Earth and in Space- use Newton's third law.
In practical terms, the difference is that Ion engines use energy from the sun, to accellerate small portions of matter (ions) over a long period of time.
Rockets use chemical energy to throw out matter, typically violently for a short period of time.
For these reasons Ion engines are predicted a bright future for travel over long distances (to the moon is unusually short in this context), there efficient use of energy wins out in the long run.
However, it seems unlikely that they could be used for lifting things into orbit; then you need to quickly accelerate to high speeds and get out of the athmosphere. Ion Engines are probably not suitable for chasing X-Wings around the Death Star either for that matter.
Let's start from planet. Planet is a body orbiting a sun, which do not emit light on its own.
A moon is a body orbiting a planet. It may be just a bigger rock, like Phobos and Deimos around Mars or a big one like our Moon. But of course it must be smaller than a planet.
This is not a formal definition of course:-)
Sorry, it is not quite that simple. A planet does indeed orbit the sun, but it must also have a certain size. Minor rocks orbiting the sun are asteroids. There is currently some controversy over exactly how big it should be in order to be called a planet; some use Pluto as the smallest possible size for a planet. But recently they have found quite a few rocks almost the size of Pluto, which has led some astronomers to the opinion that PLuto should lose its planethood, and a bigger threshold size established.
As for moons, they must orbit planets and they must also have some minimum size; I think they typically are at least a few miles across before they are called moons. However, they do not need to be smaller than planets. There are several moons which are bigger than Pluto, for example.
"Chance favours the prepared mind." - Louis Pasteur
I interpret this as an argument in favor for being well prepared and planning things in advance.
And indeed, in many activities (rocket engineering, for example), it is necessary to proceed that way.
But in most circumstances it is very subjective. Vacation planning is the textbook example. Some people ("J") are careful to make advance bookings of hotels and restaurants. Others ("P") can show up at the airport with a small bag and hoping to catch a flight to an arbitrary location.
In such cases it is meaningless to try to say that one way is better than the other. It is simply a matter of personal preferences; how we feel about risks and oportunities.
In the famous Meyer Brigg's [spelling?] personality test Murphy's law is commonly associated with the "J" type personality.
J is for judgemental; it is the 50% of people who like to be well organized and plan things in advance.
Murphy's law basically says that you should always do more preparations and planning to be better prepared; it thus rings very well with this group.
The other half of the population are much more interested in living in the present, for them the idea of always doing more preparations and planning for the future is not so appealing at all.
The problem is our global economy (due mainly to legislation like the 1996 Telcom Act) has ended up with less competition and larger players, and when they can't quickly adapt to meet the needs of the new marketplace, they try to scare (RIAA), Mislead (AT&T) or coerce (Network Solutions) consumers into continuing to do business with them.
Hum... I don't agree that global economy leads to less competition. In Telecom, international competition has forced prices way down. Calling to and from Europe to the US has changed from a dollar to a few cents per minutes in the last 20 years. Also, markets with a few large players can still be extremely competitive.
However, I do agree with your basic idea that businesses have to adapt to survive. I think the basic problem of the RIAA is that they are basically redundant at this point. There is nowhere for them to go. They could be replaced by independent recording studios and commercial download sites. It is only to be expected that they are going to fight to the last drop of blood.
2. It is uncomfortable to read from light-emitting screens for long. This problem may be overcome in the future with "electronic paper" and such
3. Sense of ownership. Most people prefer to have a physical item as a proof of ownership. I hope this cultural preference will change because it really is a waste of reasources to store books on printed papers and music on CDs.
Slashdot Mirror
I have mixed feelings about this. I am from Sweden, and it always looks kind of ugly when names lose their dots and circles in the domain name.
On the other hand, this is also quite convenient. I live in the US now, and I travel around quite a bit. I often surf on Swedish Internet sites, typically without access to a Swedish keyboard. It would not be very convenient if the domain names used non-English symbols.
Sometimes I go to Japanese sites also, and I am really glad that I don't have to install a Japanese word processor to do this...
Tor
One thing I'm not clear about when we're talking about sub-atomic particles - how do we know we've got it right?
As far as scientists are concerned, they got it right when they make predictions that are verified by experiments. Period. Whether it is "true" or a "misleading abstraction" is for the philosophers and the priests to sort out.
In this case, they did not get it right because the new particle was not predicted. This has lead to new hypothesis such as a 4-quark particle. If such an hypothesis acurately predicts the outcome of additional experiements, then it is right enough for the scientists. Some philosophers and the priests may disagree but at least they have to concede that the scientific hypothesis was useful - it predicted a novel phenomenon.
Tor
At any rate, natural evolution proceeds at a slow rate, so the defending species has time to adapt.
Natural evolution is not slow for viruses; their genetic code does not have the copy-protection mechanisms of say mammals. That is why we have a new flu pop up every other year, or a SARS for that matter.
Anthrax, for example, implements a tricky chemical hack to breach animal cells and destroy them. Most animals are pretty defenseless against the special back door that antrax uses, and without it the anthrax bacteria would be no more harmful than a pimple. However, anthrax is a rather obscure organism that mostly lives in the dirt. The reason that animals haven't evolved a defense against its chemical attack is that it just doesn't spread that easily in a natural setting. If anthrax were contagious like a cold, animals would have evolved a defense against it long ago.
With all due respect I think you are contradicting yourself. When a patheogen spreads for natural or not so natural reasons, people may die. Some survive, the resistant genes thus become more common. There may even be mutations of strong resistance that start to spread.
When this process happens for natural reasons, you label it "evolving a defense", or "defending species having time to adapt". When it happens by an act of man, you think of it as man being caught "defenseless". Of course, in both cases the species start out as (relatively) defenseless, and end up with a better defense.
My whole point was that there seem to be no lab-made pahtogen worse than anything evolved in nature. As for spreading it by man, well, anthrax did get an assist by man. But the extent of that "outbreak" was miniscule next to the natural outbreaks that happen every year.
Unless somebody figures out how to make an artificial microbe that takes advantage of chemical processes that just aren't found in natural evolution. For example, the human body might not even be capable of attacking a hypothetical microbe that has a teflon or silicone-enhanced outer membrane.
Possibly. But then again, if such mechanisms were very successful, why did they not evolve for 4 billion years on a planet surface covered in silicon compounds. In general, it is very difficult for people in labs to compete with the lab which is our planet, and time-scales of millions or billions of years.
Tor
I'm not a luddite and not really affraid this new virus is going to do something horrible like download copyright music from the RIAA. But what makes this new man-made virus any less capable of mutating or evolving than any other virus?
Probably nothing. But my point was not that we should not be careful. My point was that there should be no need to be significantly more careful than we are with other viruses.
The original post questioned whether "we really should be doing this". My response is: are you equally concerned by the everyday handling of viruses in thousands of research labs? Why not?
Tor
Technically it's not life. There is still a bit of dispute as to whether virused are alive or not. They contain genetic material, but are not necessarily living organisms. Or that is what some bio major told me once.
Whether virus is life or not depends on the definition of life. There is no consensus on this defintion, so debates on the matter are rather meaningless, it is really disputes over the definition of a word.
What makes viruses controversial is that they cannot reproduce by themselves; they need to infect antoher cell. But then again, many parasites cannot live without some other organism, and they are usuually considered alive.
Tor
Probably the same as in handling any other virus.
Which is perfectly reasonable. People seem to be exremely afraid of anything made in a lab, but fail to recognize that the greater danger (by far) is from natural evolution of new viruses.
By the same token, the dangers of bio-weapons seem to be greatly excaggerated, when compared to natural pathogens. Some anthrax letters that killed half a dozen people seemed to get more attention and resources than the flu and aids, which kill tens of thousands of people per year in the US alone.
Tor
I'm Canadian. I love 2 hours away from the United States. And take my word for it, there is NOBODY here who envies the United States. Pity might be a better word.
My point was not that the US is the center of the universe. Rather I wished to point out the contradiction in the original post. How can one expect the US to provide music downloading for the world, and at the same time be angry because the US think it is great?
Good for you to be so happy in Canada. Of course your hapiness is not uncommon; anthopologists are well aware that citizens of virtually all societies (including the US, Canada, and the most primitive stone-age tribes in Africa) are convinved that their own society is the best in the world.
Tor
As it stands, when things like this happen, it just demonstrates that the United States still thinks that it's the center of the Universe. Grrr.
And what proves that the US is right is the fact that Europe does not simply construct their own system, but rather directs its energy to anger and envy towards the US.
Tor
Probably? Assuredly, I would say. If transistor count continues to double every 2 years, with 42M transistors per CPU in 2000, you would have 43 billion in 2010, 44 trillion in 2020, 47*10^21 in 2050, and 53*10^36 in 2100. If that hasn't reached the number of atoms in the known universe, then keep counting years and it will.
The number of atoms in the universe is not the limit for computation. The true limit is set by quantum states. It is actually possible to caluclate these limits, Professor Seth Lloyd at MIT calculated how much computation can possibly come out of 1kg of matter confined to a volume of 1l - "the ultimate laptop". And yes, if Moore's law keeps going then we will be there in a few hundered years. Of course, it could be argued that we will never get there in pracitce. On the other hand, current quantum computers are nearly optimal in this regard - unfortunately they only contain a few atoms or so...
Tor
I would think the author would go back to at least 2,000 BCE or even 10,000 and identify the collosal leap made in farming. For a species to go from forraging to agrigulture seems like an enormous effort of overlapping memes (and luck).
1. Agriculture developed independently on many places of the planet.
2. The purpose of the study was not to have a cool ranking list but to identify how society and institutions should be run to foster innovation in various fields. It seems unlikely that trying to squize in some patchy data from the stone age would help achieving that goal.
Tor
Preventing roll-overs: Buy a car that's not top-heavy. If you have a real need for an SUV that is top-heavy, don't try to drive it like a car, because it's not. It's a truck, and you should be aware of that (ie, avoid turning sharply, braking suddenly, etc). The newer cross-over and car-based SUVs (Chrysler Pacifica, Porsche Cayenne/VW Touareg, Infiniti FX models, etc) are much better in this respect. I'm referring mostly to the body-on-frame truck-based SUVs. I don't drive my huge F250 like I do my Boxster, simply because the F250 doesn't handle like the Boxster does.
You seem to have missed that this is a race through a desert, partly off-road. The vehicles of choice will probably be hummers and buggys, and even these will flip if pushed too hard.
Tor
have a crappy knife, a crappy magnifying glass, a crappy saw, crappy tweezers... but their business has been going gangbusters for decades. So I'd say you're not necessarily a dying breed, there has always been a market for "do everything, crappily
And the reason for this market is that when you are out camping, it is not so convenient to put a great knife, a great magnifying glass, a great saw and a great set of tweezers in your pocket.
Similarly, I find it inconvenient to always carry around a camera, a PDA and a cellphone. I think I will get one of these things when they get a bit cheaper. I realize that the camera will not be a Hasselblad but on the other hand I will always have access to it.
Tor
Seriously though, this brings back the same question as posed on last Monday, in this article: Death of the PDA?
For me, the key problem, which seems hard to engineer around, is this:
1)I would like the device to be so small that I can put it in my pocket
2)I would like the display to be bigger than would fit in my pocket.
Even if the device has both a phone and a to-do list it can only do either 1) or 2) for me, not both. Those that only do 1) we can call cell phones and those that can only do 2) PDAs. This new Sony Ericsson seems to be somewhere in between; display on the small side (for a PDA) and uncomfortable in a pocket (compared to a cell phone)...
Tor
What's wrong with a working business model that's paid for by taxpayers?
The roads you're so fond of driving your climate-changing SUV are working under a business model that's heavily paid for by taxpayers, boy.
Why on earth should tax payers subsidize concorde travel, a luxery goods enjoyed by a priviledged few?
I hate driving and I don't have a car, let alone an SUV. I would be all in favor for reducing government spending on roads. Although admitevly, economic theory does lend some support for tax supported basic infrastructure (free-rider-problem). The same can not be said about concorde travel.
Tor
1. A glass cockpit instead of the analog crap in the old concorde
2. More efficient turbofan engines instead of the gas-guzzling turbojets on the Concorde.
3. A more roomy cabin
4. A working business model / not paid for by taxpayers
Tor
But back around 1900 or so, the Supreme Court managed to grant the rights of personhood to corporations. So there is precedent for granting rights to non-humans, though corporations are 'assemblies of humans.' But assuming a true AI has been built/programmed by humans, I guess it could be considered an 'assembly of humans,' too.
It is quite self-evident that assemblies of humans must have the rights of individual humans. What is the alternative? To prevent you and your friends from making a joint statement or joint decision, or from cooperate in your pursuit of happiness? The only significant right a corporation has that a group cooperating humans does not is that if the cooperation goes belly up, the lenders cannot take the personal money from the share holders. If you are uncomfortable with this right then you are perfectly free never to lend your money to a corporation and thus not expose yourself to such a risk.
But the corporation is still under control of humans, specifically in proportion to their ownership of stock. It can be terminated by those owners. Similarly, an AI can be terminated by its owner by current legislation, and the morality of this is what is being questioned.
Tor
, they are redundant at this point.
Sure, they may lose/ piss off customers but they really don't have an alternative business model.
Their business is to distribute music; and guess what, that can be done for dirt cheap by anyone now. It is to be expected that RIAA will fight to the bitter end.
I only hope that more artists realize this as well...
Tor
A lot of the course notes aren't particularly useful without a teacher actually explaining things to you. For example, look at the following link . While some of the notes may be useful and educational, I don't think it replaces a real, live professor explaning things and available to answer questions.
1. I don't think anybody was suggesting that this should replace real profs at MIT. This is extra resources for people outside of universities, who don't have the option of talking to a prof.
2 Personally, I actually disagree with your point. I have found that I learn the most reading and solving problems, not when I listen to somebody talking (especially not in the big lecture format).
Tor
In other words: the maximum push of ion engine is only limited by the energy source and technical competence in high-voltage engineering, not by any inherent flaw in the technology. An ion engine is perfectly capable of lifting from Earth surface (or chasing X-Wings) assuming you have a suitable power source (nuclear reactor, most likely) and power trasporting/transforming equipment (wires and a voltage converter).
This is very true, but
1 All ion engines currently discussed use solar cells as their energy source. The whole point is that you only bring matter, not the energy source to accelerate it.
2 If you are prepared to bring an energy source as well, then you are basically back to the rocket case. Sure, you can bring a nuclear reactor, use heated atoms to drive a turbine and generate electricity, and then use the electricity to accellerate ions. But then it is more efficient to use your reactor to throw out particles directly, skipping the step of turbines and electricity generation. Btw researchers are working on such nuclear rocket systems. These would be much more efficient than anything we have today, but also politically problematic to say the least.
Tor
Rockets use the same priciple that ion propulsion uses, the law of action and reaction (one of Newton's Laws, can't remember which one off the top of my head). Basically matter is accellerated out the back of the engine (by chemical means in the chemical rocket engine, and by using electro-magnetic forces in the ion propulsion engine). This accelleration causes causes a force to be placed on the engine that is equal to, but oppisite in direction, to the force accellerating the matter.
All means of propulsion -on Earth and in Space- use Newton's third law.
In practical terms, the difference is that Ion engines use energy from the sun, to accellerate small portions of matter (ions) over a long period of time.
Rockets use chemical energy to throw out matter, typically violently for a short period of time.
For these reasons Ion engines are predicted a bright future for travel over long distances (to the moon is unusually short in this context), there efficient use of energy wins out in the long run.
However, it seems unlikely that they could be used for lifting things into orbit; then you need to quickly accelerate to high speeds and get out of the athmosphere. Ion Engines are probably not suitable for chasing X-Wings around the Death Star either for that matter.
Tor
Let's start from planet. Planet is a body orbiting a sun, which do not emit light on its own. A moon is a body orbiting a planet. It may be just a bigger rock, like Phobos and Deimos around Mars or a big one like our Moon. But of course it must be smaller than a planet. This is not a formal definition of course :-)
Sorry, it is not quite that simple. A planet does indeed orbit the sun, but it must also have a certain size. Minor rocks orbiting the sun are asteroids. There is currently some controversy over exactly how big it should be in order to be called a planet; some use Pluto as the smallest possible size for a planet. But recently they have found quite a few rocks almost the size of Pluto, which has led some astronomers to the opinion that PLuto should lose its planethood, and a bigger threshold size established.
As for moons, they must orbit planets and they must also have some minimum size; I think they typically are at least a few miles across before they are called moons. However, they do not need to be smaller than planets. There are several moons which are bigger than Pluto, for example.
Tor
"Chance favours the prepared mind." - Louis Pasteur
I interpret this as an argument in favor for being well prepared and planning things in advance.
And indeed, in many activities (rocket engineering, for example), it is necessary to proceed that way.
But in most circumstances it is very subjective. Vacation planning is the textbook example. Some people ("J") are careful to make advance bookings of hotels and restaurants. Others ("P") can show up at the airport with a small bag and hoping to catch a flight to an arbitrary location.
In such cases it is meaningless to try to say that one way is better than the other. It is simply a matter of personal preferences; how we feel about risks and oportunities.
Tor
In the famous Meyer Brigg's [spelling?] personality test Murphy's law is commonly associated with the "J" type personality.
J is for judgemental; it is the 50% of people who like to be well organized and plan things in advance.
Murphy's law basically says that you should always do more preparations and planning to be better prepared; it thus rings very well with this group.
The other half of the population are much more interested in living in the present, for them the idea of always doing more preparations and planning for the future is not so appealing at all.
Tor
The problem is our global economy (due mainly to legislation like the 1996 Telcom Act) has ended up with less competition and larger players, and when they can't quickly adapt to meet the needs of the new marketplace, they try to scare (RIAA), Mislead (AT&T) or coerce (Network Solutions) consumers into continuing to do business with them.
Hum... I don't agree that global economy leads to less competition. In Telecom, international competition has forced prices way down. Calling to and from Europe to the US has changed from a dollar to a few cents per minutes in the last 20 years. Also, markets with a few large players can still be extremely competitive.
However, I do agree with your basic idea that businesses have to adapt to survive. I think the basic problem of the RIAA is that they are basically redundant at this point. There is nowhere for them to go. They could be replaced by independent recording studios and commercial download sites. It is only to be expected that they are going to fight to the last drop of blood.
Tor
2. It is uncomfortable to read from light-emitting screens for long. This problem may be overcome in the future with "electronic paper" and such
3. Sense of ownership. Most people prefer to have a physical item as a proof of ownership. I hope this cultural preference will change because it really is a waste of reasources to store books on printed papers and music on CDs.
Tor