How much of a fuss? You can forget to charge. You could be somewhere where you have no charger. You're forced to carry a charger around when traveling.
Of course none of these are atrocities, they make me think why I would want such a device, when my existing watch does exactly what I want it to do and does it reliably. Is checking emails really worth it? Those who complain about 'first world problems' would do well to think about their own first world problems, of which the need to have your emails/messages on the wrist is one. The ability to tell time, on the other hand, is very much a universal and important problem.
> We're not developing new rockets from scratch because we forgot, we're doing it because the old tech is obsolete and being replaced by new tech.
If by 'new tech' you refer to the SLS, it's largely based on the space shuttle, which is 1970's technology.
> Down in this sense means no advances or even the forgetting of things. Name one field where this is occurring to any significance.
I'll name two. Nuclear and space technology are areas where this has happened due to a large proportion of research in the 1960's and 1970's being conducted by the government and thus classified. This includes developments in nuclear refinement and reactor technology, nuclear simulation technology, rocketry, space-based optics, and many more. Most of this information is still highly confidential. As the people who had this knowledge or means of accessing this knowledge in their heads have been retiring and dying off, we've lost a huge amount of information. As a result companies like SpaceX have had to 'reinvent' a lot of old technology.
Average life expectancy has actually been going down recently, at least in the US.
Computer technology was a huge paradigm shift and saw massive growth during the 1970-2000 time period but has now stalled. Computers may still slowly improve but it's unlikely we'll see that level of growth again.
A large proportion of that huge population growth from 1.8 billion to 6 billion occurred in the developing world and is unsustainable; there are predictions now that human population will max out at 9 billion before starting to plateau or decrease.
We landed on the moon in 1969 and have made little progress in space colonization since then (and it's up for debate whether human space colonization is even worth it). The original scientists that worked on the Saturn V rocket are either dead or retired. If we wanted to develop another heavy-lift rocket we'd have to engineer it from pretty much scratch (as we are in fact doing).
The progress of technology isn't a monotonic upwards curve. It has ups and downs. A lot of indications are that we are now in one of the 'down' periods.
Is it just me or is Orbital Sciences' track record extremely poor? Something like half their rockets fail and they give nothing but excuses. Their Taurus rocket had a 33% failure rate http://www.cnet.com/news/nasa-...
It may be time to look into how they manage their company.
It explains everyone. Society rewards confidence, even if that confidence is wrong. It does not reward ability at all, at least not directly.
If you know something and are confident in it, people listen. If you don't know something but are confident in it, people listen. If you know something but aren't confident in it, people won't listen. If you don't know something and aren't confident in it, people won't listen.
The only exception to this is when you have been wrong so many times that people gradually stop taking your confidence at face value. But you can still rile up support again through a few sound-bites and appeals to the lowest common denominator. After all, we all know that the ability to come up with a witty one-liner on the spot demonstrates intelligence and wit.
> And you are assuming that every City, County, property owner, etc wants to and will outfit roads with sensors and markers and update a database, all for Google's benefit.
Do you know how much it costs to install a traffic light? It would not be demanding much to also type in a few numbers in a database. And it's not 'for Google's benefit', it's for the benefit of those who are riding in Google's cars.
> The problem with your "insightful" solution is that if the car must rely on a third party source for its information, there is a huge risk that the third party will not have provided it at all or has provided incorrect information.
True, but human drivers rely on third-party sources for information. When you're driving you rely on numerous signs and markings to give you information about the driving situation ahead. You also rely on other drivers to give you information about their intentions and how you can react. A database is only one part of the equation. Another part - which I mentioned in my comment - is making existing traffic markers more accessible to machines.
> Why not just LET THE PHYSICAL WORLD BE THE DATABASE.
As opposed to what? The spiritual world?
> The cars need to be able to drive themselves without this data and it was incredibly short sighted of Google to base their car on scanning everything.
But it doesn't. It uses machine vision for a huge number of things. It's not just LIDAR. That would not work.
> The cost is too great to do it for the small few. So fuck them. Basically that's what it amounts too. And rightfully so.
True. Electric charging stations are insanely expensive and take up space. But adding an IR or radio transmitter (for example) to an existing traffic light would cost like $2. Compared to the cost of installing a traffic light, that's nothing.
> And even if the city does change, the rural world won't. Rural towns don't have the money to paint some of the roads.
True, but then, rural towns don't have nearly as much traffic. So it seems there's far less danger of a self-driving car causing a serious accident in your average rural setting, unless you have dangerous situations like mountain passes without guard rails.
almost genius in its idiocy. If self-driving cars really start to hit the roads, cities would definitely mandate that all traffic lights show up in maps, and require that traffic lights show up in maps before being installed. This is not a problem of the driving car, it's a problem of trying to imagine future technology in a current context, which is of course always going to lead you astray.
Plus, as other commenters have said, self-driving cars can definitely recognize traffic lights. It's just that right now they aren't quite as good at doing that as humans are. The reason is that traffic lights and construction cones and stuff like that are optimized for human visibility, not robot visibility. It's quite trivial to adapt them for robot visibility as well (perhaps even incorporating stuff like specialized radio signals).
I predict that horseless carriages will never take off because without an animal like a horse with hooves on the ground, you could hit rocks and fall into ditches without knowing it.
All nuclear physics is, almost by definition, high-energy. This is especially true when talking about absorbing and/or emitting particles, which we are. I knew when the guy who wrote this article talked about muon-catalyzed fusion, it would create a wave of misunderstanding. Muon-catalyzed fusion isn't cold fusion. It's _HOT_ fusion. Once you get past that barrier and get the protons to hug in a tight embrace, you're going to get a LOT of energy. In the form of neutrons and gamma rays, and not just heat. It matters naught how that act of nuclear consummation happens.
> Why is it so inconceivable that some other reaction mechanism, which keeps the nuclei in close proximity at lower energies for longer times, has different preferences for reaction pathways?
But I don't care about that nor did I make any reference to it. I'm asking what kind of reaction it is.
> Why assume neutrons or gammas if you don't understand what's going on?
Because we understand nuclear physics very well. And all known pathways for the type of fusion they are proposing involve radiation. And not just a little - a LOT of radiation. They also involve a huge number of unstable isotopes, none of which have been observed. We're talking about high-Z isotopes here, stuff like *nickel* (!!!) for crying out loud. This is the kind of stuff that happens in supernovas. Everyone in Andrea Rossi's experiment should be dead. And not only that, their bodies should be sterilized and preserved from any further decomposition.
Maybe you should actually read up on the cold fusion people's absurd claims before rushing to defend them.
If fusion is really happening then where are the neutrons? Where's the gamma radiation? Nuclear physics doesn't work this way. When pressed about lack of radiation, they (the cold fusion people) always change the subject or make up some gibberish argument that makes no sense. The absolute best argument they can come up with is some bogus idea about reverse beta decay. Unfortunately if you actually crunch the numbers (it's literally a two-line calculation), this turns out to be incredibly impossible. Again, when pressed, they change the subject. This isn't a scientific attitude.
I'd be ECSTATIC to be proven wrong; a cheap and plentiful source of energy like that would be the earth-shattering invention that would change all of humanity forever, for the better. But it's foolish to put your hope in these things.
Fusion has a notorious history of people building a small-scale 'demonstration' of some reactor concept, measuring a few neutrons, then making grandiose claims about how it will scale up to hundreds of megawatts. Which of course never pans out because of plasma instability issues - which we are far from figuring out.
Don't get me wrong, I'm no luddite, I think we will have fusion eventually. But color me skeptical about this lockheed project.
I've pitched investors on a variety of ideas. Investors would absolutely NOT throw money at someone claiming to have a cold fusion device. They would laugh in his face and show him the door (and rightfully so). Bringing in independent experts (under an NDA) is quite a logical first step before asking for money.
Granted, the way he's doing this is highly suspect. The 'independent experts' are not allowed to actually look at the device's internals; aren't allowed to set up all their own measuring equipment, and aren't allowed to load the fuel. That part of this story is quite suspicious and, as I said, it's probably a hoax. But speaking in general, you can't fault a guy for trying to build up evidence and documentation before cashing in.
> This, a thousand times over. Having a "free energy" machine, if it existed, would be like owning a machine that printed money.
Given a choice between making $400k a year (minus operating and maintenance expenses, which we have no idea of) and potentially making billions off an invention, which would you choose?
I'm not saying that this crazy e-cat device works. Based on what we know from physics, it's far more likely that it's a hoax (until they can produce evidence otherwise). I'm just saying that there is no reason to think he's a hoax just based on his business strategy. James Watt sold steam engines, not power.
> You can also read his thinking about the Wardenclyffe tower in his patents. He had RF propagation all wrong. He thought the ionosphere was a conductive layer. His plan was to punch through to the ionosphere by ionizing a path all the way up (!), and transmit power and signals conductively, using the ionosphere and the ground as a pair of conductors.
I'm not sure where you're getting that from, but by looking through his writings I came to a completely different conclusion. You're right about his thinking that the ionosphere was a conductive layer, but he didn't intend to punch a current path through it. Instead he reasoned that the ground+atmosphere+ionosphere system was a huge resonant circuit. His idea was to excite it at its resonant frequency so that it would be able to store huge amounts of power which could then be tapped anywhere in the world.
The error is not small. If you read the article, on certain very reasonable inputs (not pathological at all), you can sometimes wind up with only _four_ bits being correct.
Many scientific applications absolutely depend on fast hardware sine implementation. As you said, getting it exactly right isn't a tradeoff that people usually want to make.
This has nothing to do with the C standard. Intel's own documentation was incorrect, making 'YMMV' completely moot.
After reading a few of your posts, I think I actually get what you're trying to convey.
I think you're confusing the general fucked-upness of society with some kind of communist plot. Then you're taking the extreme opposite view - free market capitalism - which is also wrong. I'd be the first to agree with you that society is fucked up so many ways beyond repair. The values that used to hold society together are pretty much gone. Everyone just wants free shit, and to be coddled and taken care of. That's NOT what I'm talking about.
Also, if you're angry that people in general try to take advantage of those who have money, well... man up and handle it. If you have a pie, of course lots of people going to try to steal a piece of your pie. That has nothing to do with socialism or capitalism, it's human nature. Part of running a business (in fact the most important part) is being wise to people's acts and deflecting those who try to take advantage of you.
I founded a successful business, from concept to turning a profit. Made a good amount of money too. I've seen the ins and outs of the 'capitalist' system, and it's ugly. You're right that small businesses are being destroyed. But gov't is not the (main) culprit. It's large businesses.
You're right that what we have isn't capitalism. But it's not socialism either. It's socialism for the rich and 'fuck you' for the poor. At least if it was free-market capitalism we wouldn't be hypocrites.
Take healthcare. Believe it or not, we have enough money to, for instance, offer affordable health care for every single person - without shoving the premium onto the shoulders of young people like Obamacare does. But we're not going to do that. Because 'socialism is evil!' or something.
Oh it definitely is a leisure society - for the top 1%. See, a while ago the rich assholes figured out that as computer technology was improving, people were working less and less. But they couldn't bear to have people working 20-hour weeks and getting paid for 60 hours of work. Instead they decided that they would fire 2/3 of the workforce, push the remaining 1/3 to insane limits, end silly stuff like employee bonuses or overtime, and call it 'restructuring'.
And what about the possibility that the government will catch on to this scheme and force them to pay their dues back to society? They've insured themselves against that - by making the word 'Socialist!' toxic and propping up Fox News.
They are smarter than you. The amount of ink in the included cartridges is small enough that even if you never buy ink and make 1/2 the money back from selling the printer, you're still not going to be printing more pages.
Sure, you could recoup the cost of the printer from selling parts on ebay, but is that time and effort really worth a few dozen pages of printed material? I just use commercial printing services or (when I have access to one) a laser printer.
> (although at some field densities with the right fuels and energy input, the math shows there is the potential for limited amounts of fusion)
It's not hard to achieve fusion. What's hard is getting more energy than you put in. VASIMR can never produce a self-sustaining fusion reaction unless you're talking about gigawatt-scale power levels. And even then, there's no indication that it will actually work in practice (it most certainly won't, if decades of experience in plasma physics is anything to go by).
> Frankly, this is territory we've not explored really,
Except a whole lot of really smart engineers have explored fission reactors in space and could not come up with a reasonable plan for the type of power densities required. Look at, for instance, the JIMO project: http://en.wikipedia.org/wiki/J...
A Fission-powered VASIMR rocket to Mars that could get there in 2 weeks remains a fairytale. Again, though, VASIMR could be highly useful for other purposes, like increasing mission payload (instead of shortening mission length) or for missions to other solar system bodies.
Yes, some nuclear engines were tested and yes, none of them exactly blew up. But nuclear engines wouldn't make a Mars trip any less expensive or much shorter. It's estimated that a nuclear rocket would shorten the length of a Mars trip from 6 months to... 4 months. And this would come at huge increase in mission complexity and cost. Not worth it.
For exploring the outer solar system, though, nuclear rockets could have value.
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How much of a fuss? You can forget to charge. You could be somewhere where you have no charger. You're forced to carry a charger around when traveling.
Of course none of these are atrocities, they make me think why I would want such a device, when my existing watch does exactly what I want it to do and does it reliably. Is checking emails really worth it? Those who complain about 'first world problems' would do well to think about their own first world problems, of which the need to have your emails/messages on the wrist is one. The ability to tell time, on the other hand, is very much a universal and important problem.
You're right about the US in general; I should have said in SOME parts of the US: http://theweek.com/article/ind....
> We're not developing new rockets from scratch because we forgot, we're doing it because the old tech is obsolete and being replaced by new tech.
If by 'new tech' you refer to the SLS, it's largely based on the space shuttle, which is 1970's technology.
> Down in this sense means no advances or even the forgetting of things. Name one field where this is occurring to any significance.
I'll name two. Nuclear and space technology are areas where this has happened due to a large proportion of research in the 1960's and 1970's being conducted by the government and thus classified. This includes developments in nuclear refinement and reactor technology, nuclear simulation technology, rocketry, space-based optics, and many more. Most of this information is still highly confidential. As the people who had this knowledge or means of accessing this knowledge in their heads have been retiring and dying off, we've lost a huge amount of information. As a result companies like SpaceX have had to 'reinvent' a lot of old technology.
Average life expectancy has actually been going down recently, at least in the US.
Computer technology was a huge paradigm shift and saw massive growth during the 1970-2000 time period but has now stalled. Computers may still slowly improve but it's unlikely we'll see that level of growth again.
A large proportion of that huge population growth from 1.8 billion to 6 billion occurred in the developing world and is unsustainable; there are predictions now that human population will max out at 9 billion before starting to plateau or decrease.
We landed on the moon in 1969 and have made little progress in space colonization since then (and it's up for debate whether human space colonization is even worth it). The original scientists that worked on the Saturn V rocket are either dead or retired. If we wanted to develop another heavy-lift rocket we'd have to engineer it from pretty much scratch (as we are in fact doing).
The progress of technology isn't a monotonic upwards curve. It has ups and downs. A lot of indications are that we are now in one of the 'down' periods.
Is it just me or is Orbital Sciences' track record extremely poor? Something like half their rockets fail and they give nothing but excuses. Their Taurus rocket had a 33% failure rate http://www.cnet.com/news/nasa-...
It may be time to look into how they manage their company.
It explains everyone. Society rewards confidence, even if that confidence is wrong. It does not reward ability at all, at least not directly.
If you know something and are confident in it, people listen.
If you don't know something but are confident in it, people listen.
If you know something but aren't confident in it, people won't listen.
If you don't know something and aren't confident in it, people won't listen.
The only exception to this is when you have been wrong so many times that people gradually stop taking your confidence at face value. But you can still rile up support again through a few sound-bites and appeals to the lowest common denominator. After all, we all know that the ability to come up with a witty one-liner on the spot demonstrates intelligence and wit.
People are dumb (myself included).
s/LIDAR/maps and LIDAR.
> And you are assuming that every City, County, property owner, etc wants to and will outfit roads with sensors and markers and update a database, all for Google's benefit.
Do you know how much it costs to install a traffic light? It would not be demanding much to also type in a few numbers in a database. And it's not 'for Google's benefit', it's for the benefit of those who are riding in Google's cars.
> The problem with your "insightful" solution is that if the car must rely on a third party source for its information, there is a huge risk that the third party will not have provided it at all or has provided incorrect information.
True, but human drivers rely on third-party sources for information. When you're driving you rely on numerous signs and markings to give you information about the driving situation ahead. You also rely on other drivers to give you information about their intentions and how you can react. A database is only one part of the equation. Another part - which I mentioned in my comment - is making existing traffic markers more accessible to machines.
> Why not just LET THE PHYSICAL WORLD BE THE DATABASE.
As opposed to what? The spiritual world?
> The cars need to be able to drive themselves without this data and it was incredibly short sighted of Google to base their car on scanning everything.
But it doesn't. It uses machine vision for a huge number of things. It's not just LIDAR. That would not work.
> The cost is too great to do it for the small few. So fuck them. Basically that's what it amounts too. And rightfully so.
True. Electric charging stations are insanely expensive and take up space. But adding an IR or radio transmitter (for example) to an existing traffic light would cost like $2. Compared to the cost of installing a traffic light, that's nothing.
> And even if the city does change, the rural world won't. Rural towns don't have the money to paint some of the roads.
True, but then, rural towns don't have nearly as much traffic. So it seems there's far less danger of a self-driving car causing a serious accident in your average rural setting, unless you have dangerous situations like mountain passes without guard rails.
almost genius in its idiocy. If self-driving cars really start to hit the roads, cities would definitely mandate that all traffic lights show up in maps, and require that traffic lights show up in maps before being installed. This is not a problem of the driving car, it's a problem of trying to imagine future technology in a current context, which is of course always going to lead you astray.
Plus, as other commenters have said, self-driving cars can definitely recognize traffic lights. It's just that right now they aren't quite as good at doing that as humans are. The reason is that traffic lights and construction cones and stuff like that are optimized for human visibility, not robot visibility. It's quite trivial to adapt them for robot visibility as well (perhaps even incorporating stuff like specialized radio signals).
I predict that horseless carriages will never take off because without an animal like a horse with hooves on the ground, you could hit rocks and fall into ditches without knowing it.
> High energy nuclear physics, no.
All nuclear physics is, almost by definition, high-energy. This is especially true when talking about absorbing and/or emitting particles, which we are. I knew when the guy who wrote this article talked about muon-catalyzed fusion, it would create a wave of misunderstanding. Muon-catalyzed fusion isn't cold fusion. It's _HOT_ fusion. Once you get past that barrier and get the protons to hug in a tight embrace, you're going to get a LOT of energy. In the form of neutrons and gamma rays, and not just heat. It matters naught how that act of nuclear consummation happens.
> Why is it so inconceivable that some other reaction mechanism, which keeps the nuclei in close proximity at lower energies for longer times, has different preferences for reaction pathways?
But I don't care about that nor did I make any reference to it. I'm asking what kind of reaction it is.
> Why assume neutrons or gammas if you don't understand what's going on?
Because we understand nuclear physics very well. And all known pathways for the type of fusion they are proposing involve radiation. And not just a little - a LOT of radiation. They also involve a huge number of unstable isotopes, none of which have been observed. We're talking about high-Z isotopes here, stuff like *nickel* (!!!) for crying out loud. This is the kind of stuff that happens in supernovas. Everyone in Andrea Rossi's experiment should be dead. And not only that, their bodies should be sterilized and preserved from any further decomposition.
Maybe you should actually read up on the cold fusion people's absurd claims before rushing to defend them.
If fusion is really happening then where are the neutrons? Where's the gamma radiation? Nuclear physics doesn't work this way. When pressed about lack of radiation, they (the cold fusion people) always change the subject or make up some gibberish argument that makes no sense. The absolute best argument they can come up with is some bogus idea about reverse beta decay. Unfortunately if you actually crunch the numbers (it's literally a two-line calculation), this turns out to be incredibly impossible. Again, when pressed, they change the subject. This isn't a scientific attitude.
I'd be ECSTATIC to be proven wrong; a cheap and plentiful source of energy like that would be the earth-shattering invention that would change all of humanity forever, for the better. But it's foolish to put your hope in these things.
Fusion has a notorious history of people building a small-scale 'demonstration' of some reactor concept, measuring a few neutrons, then making grandiose claims about how it will scale up to hundreds of megawatts. Which of course never pans out because of plasma instability issues - which we are far from figuring out.
Don't get me wrong, I'm no luddite, I think we will have fusion eventually. But color me skeptical about this lockheed project.
> False dichotomy. In fact, making the $400k/year would rather lend credibility.
And take a huge amount of time and put the entire operation at risk.
I've pitched investors on a variety of ideas. Investors would absolutely NOT throw money at someone claiming to have a cold fusion device. They would laugh in his face and show him the door (and rightfully so). Bringing in independent experts (under an NDA) is quite a logical first step before asking for money.
Granted, the way he's doing this is highly suspect. The 'independent experts' are not allowed to actually look at the device's internals; aren't allowed to set up all their own measuring equipment, and aren't allowed to load the fuel. That part of this story is quite suspicious and, as I said, it's probably a hoax. But speaking in general, you can't fault a guy for trying to build up evidence and documentation before cashing in.
> This, a thousand times over. Having a "free energy" machine, if it existed, would be like owning a machine that printed money.
Given a choice between making $400k a year (minus operating and maintenance expenses, which we have no idea of) and potentially making billions off an invention, which would you choose?
I'm not saying that this crazy e-cat device works. Based on what we know from physics, it's far more likely that it's a hoax (until they can produce evidence otherwise). I'm just saying that there is no reason to think he's a hoax just based on his business strategy. James Watt sold steam engines, not power.
> You can also read his thinking about the Wardenclyffe tower in his patents. He had RF propagation all wrong. He thought the ionosphere was a conductive layer. His plan was to punch through to the ionosphere by ionizing a path all the way up (!), and transmit power and signals conductively, using the ionosphere and the ground as a pair of conductors.
I'm not sure where you're getting that from, but by looking through his writings I came to a completely different conclusion. You're right about his thinking that the ionosphere was a conductive layer, but he didn't intend to punch a current path through it. Instead he reasoned that the ground+atmosphere+ionosphere system was a huge resonant circuit. His idea was to excite it at its resonant frequency so that it would be able to store huge amounts of power which could then be tapped anywhere in the world.
The error is not small. If you read the article, on certain very reasonable inputs (not pathological at all), you can sometimes wind up with only _four_ bits being correct.
Many scientific applications absolutely depend on fast hardware sine implementation. As you said, getting it exactly right isn't a tradeoff that people usually want to make.
This has nothing to do with the C standard. Intel's own documentation was incorrect, making 'YMMV' completely moot.
After reading a few of your posts, I think I actually get what you're trying to convey.
I think you're confusing the general fucked-upness of society with some kind of communist plot. Then you're taking the extreme opposite view - free market capitalism - which is also wrong. I'd be the first to agree with you that society is fucked up so many ways beyond repair. The values that used to hold society together are pretty much gone. Everyone just wants free shit, and to be coddled and taken care of. That's NOT what I'm talking about.
Also, if you're angry that people in general try to take advantage of those who have money, well... man up and handle it. If you have a pie, of course lots of people going to try to steal a piece of your pie. That has nothing to do with socialism or capitalism, it's human nature. Part of running a business (in fact the most important part) is being wise to people's acts and deflecting those who try to take advantage of you.
Give it a rest.
I founded a successful business, from concept to turning a profit. Made a good amount of money too. I've seen the ins and outs of the 'capitalist' system, and it's ugly. You're right that small businesses are being destroyed. But gov't is not the (main) culprit. It's large businesses.
You're right that what we have isn't capitalism. But it's not socialism either. It's socialism for the rich and 'fuck you' for the poor. At least if it was free-market capitalism we wouldn't be hypocrites.
Take healthcare. Believe it or not, we have enough money to, for instance, offer affordable health care for every single person - without shoving the premium onto the shoulders of young people like Obamacare does. But we're not going to do that. Because 'socialism is evil!' or something.
Oh it definitely is a leisure society - for the top 1%. See, a while ago the rich assholes figured out that as computer technology was improving, people were working less and less. But they couldn't bear to have people working 20-hour weeks and getting paid for 60 hours of work. Instead they decided that they would fire 2/3 of the workforce, push the remaining 1/3 to insane limits, end silly stuff like employee bonuses or overtime, and call it 'restructuring'.
And what about the possibility that the government will catch on to this scheme and force them to pay their dues back to society? They've insured themselves against that - by making the word 'Socialist!' toxic and propping up Fox News.
They are smarter than you. The amount of ink in the included cartridges is small enough that even if you never buy ink and make 1/2 the money back from selling the printer, you're still not going to be printing more pages.
Sure, you could recoup the cost of the printer from selling parts on ebay, but is that time and effort really worth a few dozen pages of printed material? I just use commercial printing services or (when I have access to one) a laser printer.
All versions of windows have internal version numbers. XP's was 5.x I believe.
> (although at some field densities with the right fuels and energy input, the math shows there is the potential for limited amounts of fusion)
It's not hard to achieve fusion. What's hard is getting more energy than you put in. VASIMR can never produce a self-sustaining fusion reaction unless you're talking about gigawatt-scale power levels. And even then, there's no indication that it will actually work in practice (it most certainly won't, if decades of experience in plasma physics is anything to go by).
> Frankly, this is territory we've not explored really,
Except a whole lot of really smart engineers have explored fission reactors in space and could not come up with a reasonable plan for the type of power densities required. Look at, for instance, the JIMO project: http://en.wikipedia.org/wiki/J...
A Fission-powered VASIMR rocket to Mars that could get there in 2 weeks remains a fairytale. Again, though, VASIMR could be highly useful for other purposes, like increasing mission payload (instead of shortening mission length) or for missions to other solar system bodies.
VASIMR isn't a nuclear rocket, and nuclear power in space currently falls far short of the required W/kg requirements.
Yes, some nuclear engines were tested and yes, none of them exactly blew up. But nuclear engines wouldn't make a Mars trip any less expensive or much shorter. It's estimated that a nuclear rocket would shorten the length of a Mars trip from 6 months to... 4 months. And this would come at huge increase in mission complexity and cost. Not worth it.
For exploring the outer solar system, though, nuclear rockets could have value.