Fair enough. It's usually disillusionment with US policy that comes up on Slashdot, and I made an unwarranted assumption.
On the other hand, the most recent stats I can find from the National Health Service (NHS) seem to indicate that teen pregnancy rates are declining in the UK, and have been since 1998. Teen pregnancy rates in the UK, while the highest in Western Europe, still remain well below the rate in the United States.
The most recent NHS data that I could find seem to indicate that alcohol and drug use have also remained relatively flat over the last five years (changes were mostly small and within the margins of error of the survey.)
With respect to depression, I haven't checked the figures; they weren't mentioned in the original post. Part of the increase may be due to increased (over-?) diagnosis.
It's also time to start considering the possibility that Taiwan will possibly be invaded and occupied by the Communists from the mainland at some point within the next five years. This will, if it happens, disrupt manufacturing design and shipping for years to come.
Why would it disrupt manufacturing, design, and shipping for years to come?
There would just be some fast footwork in the Senate, a Presidential edict or two, some bafflegab from the State Department, a treaty-signing photo-op, and suddenly buying all that hardware from the Chinese government is nice and legal. What do you think Silicon Valley is paying all those lobbyists for?
You weren't thinking there would be trade sanctions against China--even if they invade Taiwan--were you? They'd have to invade California before the US government would upset that many multinationals.
If I were an American politician, I would suggest to the US State department that the USA would only guarantee to provide an efficient co-defense of Taiwan if Taiwan relocates a significant number of IC fabs and design centers to the USA employing primarily American workers.
And why would the Taiwanese choose to do that? If they move their important infrastructure to the United States, that reduces to zero the already-tenuous incentive for the United States to provide any defense at all...
Then we wonder why teenage pregnancies, binge drinking and drugs are at an all time high...
Minor nitpicks...
The teenage pregnancy (and abortion) rates in the United States are actually significantly lower now than they have been in the past two decades. (CDC release.) Teen pregnancy fell steeply throughout the 1990s, and continues to decline. Teen pregnancy is still higher in the United States than in other developed countries, but I suspect that that can be largely attributed to the deliberate policy of restricting information about and access to birth control techniques.
Use of most illegal drugs (including marijuana and cocaine) is actually falling. Use of alcohol among young people has also declined. (CDC summaries.
The best stated was "bio+token+password". Seems reasonable to me, at least.
This is often stated as,
something you are (biometric like fingerprint)
something you have (a token of some kind)
something you know (a password or PIN).
The best (in the sense of most secure) systems combine all three; strong systems include at least two. For those of us on Slashdot, we all know that given a modest investment of effort, we can usually steal, duplicate, or work around any one of those--but doing two or more is significantly harder.
1 lb Phlounder Bones from Phish 1 Bay leaph 4 Parsley stalks 2 Lovage stalks 6 1/4 c Cold water Sea salt 6 Black peppercorns 1 Small onion 1 Carrot 1 Leek 1/2 lb Hake 2 tb Butter 1 tb Phlour 2 tb Sour cream 2 tb Chopped phennel leaves
Put the phish bones in a pan with the bay leaph, parsley, and lovage.
Cover with cold water, add salt and peppercorns, and bring to boil.
Simmer for 30 minutes....
...that you have to call the guy at the other end and ask him to stand very very still:)
He might be able to recognize your voice. The really nerdly thing to do would be to send the guy a text message from himself, telling him to stand still.
Protecting people from child pornography has nothing to do with consumer protection.
Sure it does. When 'consuming' regular, adult pornography I don't want to be inadvertently exposed to kiddie porn. I only want to see girls of (barely) legal age.:D
$30/hour (USD or CAD) seems absurdly low for a fully-burdened labor rate, particularly for engineers and other professionals.
But not everyone on the project is an engineer or high-level professional.
Much of the work could be done by people paid as graduate students or interns--and you're looking at $12 to $15 per hour there...not to mention a few $8 per hour positions to do things like fetch coffee and move paper.
One engineer ($100 per hour) with a skilled assistant ($65/hr) and an intern ($20/hr), supported by two grad students ($15/hr each) and two gofers/summer students ($8/hr each) gives a cost of $33 per labour hour.
Further, it's silly to assume that the cost of SpaceShipOne actually includes a full cost for every hour contributed. I'm quite certain that a lot of people (some expensive and highly skilled, and some otherwise) contributed a significant amount of unpaid overtime, just because it's a fun project. If you want to use a $70 per hour average labour rate for comparing SpaceShipOne to Wild Fire (to give a total cost of $15 million) you're going to have to a) explain why all the junior, less-skilled members of the project are getting so well paid, and b) account for the unpaid hours on Scaled's project, too.
True, but if one assigns a fair market value to tens of thousands of hours of volunteer labor reportedly spent on the project, the difference between the two becomes much smaller.
From the article:
The all-volunteer da Vinci team spent about $350,000 of cash, $4 million of in-kind donations and they've put in 150,000 man-hours in pursuit of the X Prize, Feeney said.
If they paid a hypothetical $30 per hour for the volunteer labour, the total cost would still be only $8.5 million. Further, the article doesn't mention whether or not those are Canadian dollars--if they are, then you can cut another 25% or so off the cited prices. Even paying a fair price for labour, the da Vinci effort would seem to cost a third to a half the amount of SpaceShipOne.
To be fair, we are all still waiting to see if it flies.
In most circles this is called self-incrimination.
The problems with that notion are:
this is civil and not criminal law;
even in criminal law, you cannot be compelled to incriminate yourself--but if you do so the evidence is still generally admissible unless extracted under duress. Leaving a thumbprint on a gun or screaming "Oh my God, I shot my wife!" are both forms of self-incrimination, but generally both are valid evidence.
SCO isn't allowed to use discovery as purely a fishing expedition in the faint hope that they find some evidence that IBM has infringed their copyrights or breached their contracts. However, if SCO uncovers evidence of additional misdeeds as part of legitimate discovery, they're allowed to sue for the new stuff, too. (Again drawing an example from criminal law--for illustrative purposes only--if a cop pulls you over for speeding, then sees that you have a bag of cocaine on the seat beside you, then he can charge you for possession, too. On the other hand, generally the cop isn't allowed to randomly pull people over and search through their trunks on the off chance he might find some cocaine.)
In order to get to discovery, SCO has to demonstrate to a court that it has some valid reason to believe that IBM may have done the nasty things that SCO claims. The court then can compel IBM to release documents related to that issue. Usually this is a pretty low hurdle.
As an aside, SCO doesn't have to prove IBM breached their contracts. Civil cases are decided on the basis of preponderance of evidence or balance of probabilities. The court looks at the evidence and takes the side that it finds most plausible--neither side must prove their case beyond a reasonable doubt; that test is only applied in criminal law.
The current treaties aren't signed by nearly all nations, and they're furthermore written from a standpoint of the signatories and/or UN representing all of mankind and mankind having rights to pass laws for the entire universe. This again breaks down the moment there are practical means for someone to colonise outer space but not practical means to mount military operations to stop them. (Not to mention if there turns out to be life on other planets)
There are very few governments that can get anything up into space, and even fewer with the capability to softland personnel or equipment on other worlds (moons, planets, asteroids, what have you). As a practical matter, those nations are the only ones that have to agree to such restrictions--I don't care if Monaco or Madagascar refuse to sign a treaty on extraterrestrial property conventions as long as they can't get off this planet in the first place.
As a practical matter, I find it hard to believe that it would ever be impossible to stop a colonization through the use of force. The colonists are departing from Earth, after all, and the United States, Russia, China, or the Europeans all have the technical ability to...ah, deny another group the opportunity to launch. Further, do you think that any of those named powers would willingly recognize a claim by any of the others to a significant chunk of any major object?
Granted the laws don't recognize entraterrestrial intelligences--that one is going to be a problem the courts will have to address if it ever comes up.
So the energy is there, we just can't access it without serious improvements to our efficiency in creating antimatter. If advances are made to get the overall process up to a few percent of efficiency (the current process I'm proposing would be.002% efficient), interstellar travel could become slightly more realistic.
That's still a heck of an if...
Incidentally, I crunched the numbers--the relativistic kinetic energy at 0.9c is 1.16E17 J per kilogram of mass. At 0.95c, it's 1.98E17 J; at 0.99c it's 5.4E17 J.
If you're willing to settle for 0.1c, then your energy requirement drops three orders of magnitude, to 4.5E14 J per kilogram of cargo. That might be a bit easier.
Even so...solar cells typically have efficiencies in the 20% range, and they tend not to be happy at high temperature. Assuming they can be hardened for a close solar orbit, and assuming we get their efficiency up by a factor of 3 (that's the best that can be hoped for) we've got a production of energy from our football field of about 5 GW. (5E9 J/s).
Antimatter production is about 0.000001% efficient in current facilities, but they're not designed with antimatter production in mind. Applying favourable estimates and solid engineering, it is speculated that we can get an extra four orders of magnitude in efficiency, up to the neighbourhood of 0.01%.
Unless we develop some new physics, we're stuck there, but I'm willing to concede another two orders of magnitude in efficiency gains--chalk it up to 'cleverness'.
That gets us 5E7 J/s stored; that's about 1.6E15 J per year. If we allow for a 100% efficient engine (sure...), we can lob 2 kg at 0.1c each year, or ten grams at 0.9c.
As you noted, even with 100% efficient energy conversion at each step, you're only pushing a kilogram per year at 0.9c. Yer gonna need more silicon football fields in space. Thousands of them, for manned travel.
It's different than that. I'd gladly pay 25 cents a day for the Washington Post. But, I'm in Seattle. They don't distribute there. Or rather they only distribute the Sunday Paper - a week late. Bah!
I'd gladly PAY to get the regular version of the Washington Post. Unfortunately that's not an option. But I know I'm not the only one who's moved away and wants to read their local paper.
If you want physical delivery of the Washington Post, it's still available in your area. You just have to pay someone to courier, or scan and email, or fax you a copy every morning. Too expensive? Oh--well, then register online. Don't want to give up your information? Read something else. Some newspapers have the unmitigated gall to not even offer an online version.
For their readers further afield, the Post has chosen to offer their content over the internet. Instead of charging for a subscription, they ask for registration information. They're a business; they're welcome to choose how they charge for their product. For physical papers, they want cash--for electronic ones, the coin (appropriately enough) is information. If you would prefer to pay cash for access to their online content, send them a letter and let them know. If there is sufficient demand, I'm sure they'd be willing to charge for the online version. Of course, in order to set up your billing, they'd probably want to ask for your name and contact info....
I'm afraid you're going to have to check your figures on calculating kinetic energy.
For relativistic speeds, the kinetic energy is given by the formula linked here. This kinetic energy will always be greater than the energy calculated for a given velocity using the classical kinetic energy
KE = 1/2 * m * v^2
Using the classical kinetic energy formula (which will always overestimate the velocity achieved with a given quantity of kinetic energy, one obtains:
v (classical) = (2 * KE / m)^(1/2)
If we're working in SI (mks) units, everything is kosher for velocities in m/s, masses in kg, and energies in joules (1 J = 1 kg.m^2/s^2).
Using the figure of 3.09E8 J of kinetic energy per kilogram of ship you've put forward, you end up with a velocity of just shy of 2.5E4 m/s, or 25 km/s. It's going to take you more than four years just to get out of the Solar System at that speed.
Relativity states that a craft notice no change in mass from its own frame of reference. As long as the fuel is contained aboard the spaceship (the rocket formula), its mass will increase along with the rest of the ship's.
This is true, but not relevant to the discussion. I was looking at the energy content of the fuel. The rate of acceleration is neither here nor there (though in this case the calculation is correct--you get up close to c after about 1 year at 1 g acceleration). The problem is straight-up conservation of energy--if there's not the potential energy in the fuel, you can't get the kinetic energy for the spacecraft.
Also, when calculating the energy required for a given acceleration, you have to multiply the force (in newtons) by the distance (in meters).
For an acceleration of 1 g (9.8 m/s^2) of 1 kg of mass, we're looking at a force of:
Force = Mass * Acceleration
= (1 kg) * (9.8 m/s^2)
= 9.8 kg.m/s^2
= 9.8 newtons (N)
For the total work done (energy required) one has to multiply the force by the distance over which it is applied:
Work = Force * Distance
= 9.8 N * 1/2 lightyear
= 9.8 kg.m/s^2 * 4.7E15 m (Thanks Google!
= 4.6E16 kg.m^2/s^2
= 4.6E16 joules (J)
That's the gotcha that you have to watch for--the parent equated newtons with joules/second. A newton is a joule per meter. (1 J/s is a watt.) Note also that (as expected) the energy cost to achieve a given speed is a constant--if you halve the acceleration (using half the force) you double the distance over which you accelerate.
Odd as it may seem, "something near it" isn't that big of a problem.
What we need is
...lots and lots of antimatter... ...working engines that use it... ...a station placed at about 0.1 AU... ...a station with a power collecting surface the size of a football field... ...facilities necessary to transform all that power into antimatter...
Oh. Is that all? "Isn't that big of a problem" indeed...
You forgot to do the kinetic energy calculation. I'm neglecting relativistic effects out of laziness. At 0.99c (a bit less than 3E8 m/s), each kilogram of spaceship would have kinetic energy of roughly 4.4E16 joules.
Assume for a moment that we had the 148 kW antimatter yield from your proposed power system. That's 148 kJ/s, or 4.7E12 J of stored energy per year.
If we also neglect the mass of the fuel itself, and assume a 100% efficient engine, we need to operate the antimatter plant for just about 10000 years to produce enough antimatter to accelerate 1 kg of cargo (a shade over two pounds on earth) to 0.99c.
To store enough energy in one year to accelerate 1 kg of mass to 0.99c, you need something closer to five hundred square kilometers of solar panels under the engineering assumptions the parent describes. Note also that those panels are assumed to be at 0.1 AU from the Sun--inside the orbit of Mercury (mean orbital distance about 0.15 AU)--and a decidedly hostile environment for even an unmanned station.
I've also neglected to consider accelerating the mass of the antimatter propellant (only about 250 g of antimatter and an equal amount of matter per kilogram of cargo, actually) as well as the additional mass required to slow down or maneouvre at the other end of the trip. For reference, the Apollo command module weighed more than five thousand kilograms; the Shuttle orbiter weighs close to a hundred thousand. Even Sputnik I weighed 84 kg.
My main concern with black box data being used to determine fault, etc. is that currently they have little to no security other then a proprietary connector. There is nothing to prevent tampering with the "evidence". Even if the box data is encrypted, etc. you can still tamper with the vehicles sensors.
On the other hand, proposed and existing systems record only a short loop of data, that stops recording after airbag inflation or another equally traumatic event.
If your car was involved in an accident that serious, you can bet that the police would impound the wreck and secure the black box--you don't get a chance to tamper with it afterwards.
If you fudge the sensors, you'd have to a) make sure that they were faking data that was appropriate to whatever the current driving situation was, and b) brilliantly conceal your work, since the cops have physical possession of your car.
Obviously the data from the black box will almost never conclusively prove fault in an accident. However, it lends unbiased confirmation to what are typically very unreliable witness accounts. (Drivers in shock, injured, or afraid of criminal charges will misstate, forget, or lie outright. Eyewitness accounts are inherently unreliable--people suck at estimating speeds and distances, and multiple witnesses at a scene will chat before the police arrive and often reinforce an inaccurate 'consensus' view.) It also will have to hang together with physical evidence at the scene--the pattern of damage to both vehicles, the location and type of skid marks, etc.
...and just agree to be encased in styrofoam at birth, tagged with RFIDs at birth, and have video cameras installed throughout the land.
It could be argued that this is a step towards better allocation of responsibility.
The black boxes (existing and proposed) don't track your every move. They record a loop of a few (five to thirty or so) seconds, and stop writing (and overwriting) in response to certain serious events--usually airbag inflation.
It doesn't turn you in if you happen to be speeding on the Interstate. When you're in a collision, it reports that you were travelling at a reasonable speed and attempted to avoid the other car. It may also report that the other guy had the pedal to the floor and was doing ninety-five, not sixty as he claimed.
From a forensic standpoint, eyewitness reports generally suck. Bystanders are usually terrible at estimating speeds and distances. I'm confident enough in my driving ability and safety to have an impartial record of my actions prior to any accident. I'm looking forward to having a black box to support my statements in what otherwise might be a my-word-against-his situation.
If the facts I've read are correct, this isn't about property rights, it's about slavery.
Sorry; you've read the 'facts' wrong. Incidentally, the front page Slashdot blurb doesn't count as factual material.
Sometimes it's a good idea to read the actual judgement in the case. Google cache.
This comment excerpts a key point from the judgement. The 'idea' in question is a development that pertains directly to Brown's normal work duties. Further, he sent a memo to management in 1996 indicating that he had developed this idea into a workable method.
It looks a lot like he did a bit of extra work related to his job, and he's trying to shake down his former employers.
"... Oh, sounds like a cool toy, we own it of course since you used all work hardware to make it."
And he was right--you were at your workplace, using their equipment and their lab space. And the first person you told was the company CEO. If you want to do hardware development for yourself, sink ten or twenty thousand dollars into equipping your garage.
Yeah, the lawyers' attitude sucks, but their position isn't exactly unreasonable. For what it's worth, they probably would have let you have one for your own use.
To join the storm of people calling bullshit, if I was an electrician in the employ of a factory, I think that they'd be hard pressed to claim ownership of the radio I built in my basement in my spare time.
On the other hand, if you designed radios at work, the factory would have a tenable legal and moral position if you suddenly decided to start building and selling radio equipment.
The key question here is whether or not there is a significant overlap between the programming duties of the employee in this case and his official work duties. Judging by some of the other posts (including excerpts from the judgement itself) there is evidence that this is not an entirely unfounded conclusion.
Slashdot Mirror
On the other hand, the most recent stats I can find from the National Health Service (NHS) seem to indicate that teen pregnancy rates are declining in the UK, and have been since 1998. Teen pregnancy rates in the UK, while the highest in Western Europe, still remain well below the rate in the United States.
The most recent NHS data that I could find seem to indicate that alcohol and drug use have also remained relatively flat over the last five years (changes were mostly small and within the margins of error of the survey.)
With respect to depression, I haven't checked the figures; they weren't mentioned in the original post. Part of the increase may be due to increased (over-?) diagnosis.
Why would it disrupt manufacturing, design, and shipping for years to come?
There would just be some fast footwork in the Senate, a Presidential edict or two, some bafflegab from the State Department, a treaty-signing photo-op, and suddenly buying all that hardware from the Chinese government is nice and legal. What do you think Silicon Valley is paying all those lobbyists for?
You weren't thinking there would be trade sanctions against China--even if they invade Taiwan--were you? They'd have to invade California before the US government would upset that many multinationals.
If I were an American politician, I would suggest to the US State department that the USA would only guarantee to provide an efficient co-defense of Taiwan if Taiwan relocates a significant number of IC fabs and design centers to the USA employing primarily American workers.
And why would the Taiwanese choose to do that? If they move their important infrastructure to the United States, that reduces to zero the already-tenuous incentive for the United States to provide any defense at all...
You mean my Ethernet card is supposed to smoke like that?
Minor nitpicks...
The teenage pregnancy (and abortion) rates in the United States are actually significantly lower now than they have been in the past two decades. (CDC release.) Teen pregnancy fell steeply throughout the 1990s, and continues to decline. Teen pregnancy is still higher in the United States than in other developed countries, but I suspect that that can be largely attributed to the deliberate policy of restricting information about and access to birth control techniques.
Use of most illegal drugs (including marijuana and cocaine) is actually falling. Use of alcohol among young people has also declined. (CDC summaries.
This is often stated as,
something you are (biometric like fingerprint)
something you have (a token of some kind)
something you know (a password or PIN).
The best (in the sense of most secure) systems combine all three; strong systems include at least two. For those of us on Slashdot, we all know that given a modest investment of effort, we can usually steal, duplicate, or work around any one of those--but doing two or more is significantly harder.
What happens if you forget your password?
What happens if you lose the keys to your office?
Loss of the CueCat is something to be considered, but it doesn't have to be the end of the world.
He might be able to recognize your voice. The really nerdly thing to do would be to send the guy a text message from himself, telling him to stand still.
It's okay; the beta case isn't being discarded. It's just being upgraded to the final production rollout version.
Oh...you mean the Betamax case.
Yes, we're hosed.
Sure it does. When 'consuming' regular, adult pornography I don't want to be inadvertently exposed to kiddie porn. I only want to see girls of (barely) legal age. :D
But not everyone on the project is an engineer or high-level professional.
Much of the work could be done by people paid as graduate students or interns--and you're looking at $12 to $15 per hour there...not to mention a few $8 per hour positions to do things like fetch coffee and move paper.
One engineer ($100 per hour) with a skilled assistant ($65/hr) and an intern ($20/hr), supported by two grad students ($15/hr each) and two gofers/summer students ($8/hr each) gives a cost of $33 per labour hour.
Further, it's silly to assume that the cost of SpaceShipOne actually includes a full cost for every hour contributed. I'm quite certain that a lot of people (some expensive and highly skilled, and some otherwise) contributed a significant amount of unpaid overtime, just because it's a fun project. If you want to use a $70 per hour average labour rate for comparing SpaceShipOne to Wild Fire (to give a total cost of $15 million) you're going to have to a) explain why all the junior, less-skilled members of the project are getting so well paid, and b) account for the unpaid hours on Scaled's project, too.
Dude, you blew the spelling of Folgers, too.
Surrender now, and don't make it any harder on yourself.
That's odd, nobody has made some inane Al Gore related remark.
Oh, wait. Nevermind.
From the article:
If they paid a hypothetical $30 per hour for the volunteer labour, the total cost would still be only $8.5 million. Further, the article doesn't mention whether or not those are Canadian dollars--if they are, then you can cut another 25% or so off the cited prices. Even paying a fair price for labour, the da Vinci effort would seem to cost a third to a half the amount of SpaceShipOne.To be fair, we are all still waiting to see if it flies.
The problems with that notion are:
this is civil and not criminal law;
even in criminal law, you cannot be compelled to incriminate yourself--but if you do so the evidence is still generally admissible unless extracted under duress. Leaving a thumbprint on a gun or screaming "Oh my God, I shot my wife!" are both forms of self-incrimination, but generally both are valid evidence.
SCO isn't allowed to use discovery as purely a fishing expedition in the faint hope that they find some evidence that IBM has infringed their copyrights or breached their contracts. However, if SCO uncovers evidence of additional misdeeds as part of legitimate discovery, they're allowed to sue for the new stuff, too. (Again drawing an example from criminal law--for illustrative purposes only--if a cop pulls you over for speeding, then sees that you have a bag of cocaine on the seat beside you, then he can charge you for possession, too. On the other hand, generally the cop isn't allowed to randomly pull people over and search through their trunks on the off chance he might find some cocaine.)
In order to get to discovery, SCO has to demonstrate to a court that it has some valid reason to believe that IBM may have done the nasty things that SCO claims. The court then can compel IBM to release documents related to that issue. Usually this is a pretty low hurdle.
As an aside, SCO doesn't have to prove IBM breached their contracts. Civil cases are decided on the basis of preponderance of evidence or balance of probabilities. The court looks at the evidence and takes the side that it finds most plausible--neither side must prove their case beyond a reasonable doubt; that test is only applied in criminal law.
There are very few governments that can get anything up into space, and even fewer with the capability to softland personnel or equipment on other worlds (moons, planets, asteroids, what have you). As a practical matter, those nations are the only ones that have to agree to such restrictions--I don't care if Monaco or Madagascar refuse to sign a treaty on extraterrestrial property conventions as long as they can't get off this planet in the first place.
As a practical matter, I find it hard to believe that it would ever be impossible to stop a colonization through the use of force. The colonists are departing from Earth, after all, and the United States, Russia, China, or the Europeans all have the technical ability to...ah, deny another group the opportunity to launch. Further, do you think that any of those named powers would willingly recognize a claim by any of the others to a significant chunk of any major object?
Granted the laws don't recognize entraterrestrial intelligences--that one is going to be a problem the courts will have to address if it ever comes up.
That's still a heck of an if...
Incidentally, I crunched the numbers--the relativistic kinetic energy at 0.9c is 1.16E17 J per kilogram of mass. At 0.95c, it's 1.98E17 J; at 0.99c it's 5.4E17 J.
If you're willing to settle for 0.1c, then your energy requirement drops three orders of magnitude, to 4.5E14 J per kilogram of cargo. That might be a bit easier.
Even so...solar cells typically have efficiencies in the 20% range, and they tend not to be happy at high temperature. Assuming they can be hardened for a close solar orbit, and assuming we get their efficiency up by a factor of 3 (that's the best that can be hoped for) we've got a production of energy from our football field of about 5 GW. (5E9 J/s).
Antimatter production is about 0.000001% efficient in current facilities, but they're not designed with antimatter production in mind. Applying favourable estimates and solid engineering, it is speculated that we can get an extra four orders of magnitude in efficiency, up to the neighbourhood of 0.01%.
Unless we develop some new physics, we're stuck there, but I'm willing to concede another two orders of magnitude in efficiency gains--chalk it up to 'cleverness'.
That gets us 5E7 J/s stored; that's about 1.6E15 J per year. If we allow for a 100% efficient engine (sure...), we can lob 2 kg at 0.1c each year, or ten grams at 0.9c.
As you noted, even with 100% efficient energy conversion at each step, you're only pushing a kilogram per year at 0.9c. Yer gonna need more silicon football fields in space. Thousands of them, for manned travel.
I'd gladly PAY to get the regular version of the Washington Post. Unfortunately that's not an option. But I know I'm not the only one who's moved away and wants to read their local paper.
If you want physical delivery of the Washington Post, it's still available in your area. You just have to pay someone to courier, or scan and email, or fax you a copy every morning. Too expensive? Oh--well, then register online. Don't want to give up your information? Read something else. Some newspapers have the unmitigated gall to not even offer an online version.
For their readers further afield, the Post has chosen to offer their content over the internet. Instead of charging for a subscription, they ask for registration information. They're a business; they're welcome to choose how they charge for their product. For physical papers, they want cash--for electronic ones, the coin (appropriately enough) is information. If you would prefer to pay cash for access to their online content, send them a letter and let them know. If there is sufficient demand, I'm sure they'd be willing to charge for the online version. Of course, in order to set up your billing, they'd probably want to ask for your name and contact info....
For relativistic speeds, the kinetic energy is given by the formula linked here. This kinetic energy will always be greater than the energy calculated for a given velocity using the classical kinetic energy
Using the classical kinetic energy formula (which will always overestimate the velocity achieved with a given quantity of kinetic energy, one obtains: If we're working in SI (mks) units, everything is kosher for velocities in m/s, masses in kg, and energies in joules (1 J = 1 kg.m^2/s^2).Using the figure of 3.09E8 J of kinetic energy per kilogram of ship you've put forward, you end up with a velocity of just shy of 2.5E4 m/s, or 25 km/s. It's going to take you more than four years just to get out of the Solar System at that speed.
Relativity states that a craft notice no change in mass from its own frame of reference. As long as the fuel is contained aboard the spaceship (the rocket formula), its mass will increase along with the rest of the ship's.
This is true, but not relevant to the discussion. I was looking at the energy content of the fuel. The rate of acceleration is neither here nor there (though in this case the calculation is correct--you get up close to c after about 1 year at 1 g acceleration). The problem is straight-up conservation of energy--if there's not the potential energy in the fuel, you can't get the kinetic energy for the spacecraft.
Also, when calculating the energy required for a given acceleration, you have to multiply the force (in newtons) by the distance (in meters).
For an acceleration of 1 g (9.8 m/s^2) of 1 kg of mass, we're looking at a force of:
For the total work done (energy required) one has to multiply the force by the distance over which it is applied: That's the gotcha that you have to watch for--the parent equated newtons with joules/second. A newton is a joule per meter. (1 J/s is a watt.) Note also that (as expected) the energy cost to achieve a given speed is a constant--if you halve the acceleration (using half the force) you double the distance over which you accelerate.What we need is
Oh. Is that all? "Isn't that big of a problem" indeed...You forgot to do the kinetic energy calculation. I'm neglecting relativistic effects out of laziness. At 0.99c (a bit less than 3E8 m/s), each kilogram of spaceship would have kinetic energy of roughly 4.4E16 joules.
Assume for a moment that we had the 148 kW antimatter yield from your proposed power system. That's 148 kJ/s, or 4.7E12 J of stored energy per year.
If we also neglect the mass of the fuel itself, and assume a 100% efficient engine, we need to operate the antimatter plant for just about 10000 years to produce enough antimatter to accelerate 1 kg of cargo (a shade over two pounds on earth) to 0.99c.
To store enough energy in one year to accelerate 1 kg of mass to 0.99c, you need something closer to five hundred square kilometers of solar panels under the engineering assumptions the parent describes. Note also that those panels are assumed to be at 0.1 AU from the Sun--inside the orbit of Mercury (mean orbital distance about 0.15 AU)--and a decidedly hostile environment for even an unmanned station.
I've also neglected to consider accelerating the mass of the antimatter propellant (only about 250 g of antimatter and an equal amount of matter per kilogram of cargo, actually) as well as the additional mass required to slow down or maneouvre at the other end of the trip. For reference, the Apollo command module weighed more than five thousand kilograms; the Shuttle orbiter weighs close to a hundred thousand. Even Sputnik I weighed 84 kg.
On the other hand, proposed and existing systems record only a short loop of data, that stops recording after airbag inflation or another equally traumatic event.
If your car was involved in an accident that serious, you can bet that the police would impound the wreck and secure the black box--you don't get a chance to tamper with it afterwards.
If you fudge the sensors, you'd have to a) make sure that they were faking data that was appropriate to whatever the current driving situation was, and b) brilliantly conceal your work, since the cops have physical possession of your car.
Obviously the data from the black box will almost never conclusively prove fault in an accident. However, it lends unbiased confirmation to what are typically very unreliable witness accounts. (Drivers in shock, injured, or afraid of criminal charges will misstate, forget, or lie outright. Eyewitness accounts are inherently unreliable--people suck at estimating speeds and distances, and multiple witnesses at a scene will chat before the police arrive and often reinforce an inaccurate 'consensus' view.) It also will have to hang together with physical evidence at the scene--the pattern of damage to both vehicles, the location and type of skid marks, etc.
It could be argued that this is a step towards better allocation of responsibility.
The black boxes (existing and proposed) don't track your every move. They record a loop of a few (five to thirty or so) seconds, and stop writing (and overwriting) in response to certain serious events--usually airbag inflation.
It doesn't turn you in if you happen to be speeding on the Interstate. When you're in a collision, it reports that you were travelling at a reasonable speed and attempted to avoid the other car. It may also report that the other guy had the pedal to the floor and was doing ninety-five, not sixty as he claimed.
From a forensic standpoint, eyewitness reports generally suck. Bystanders are usually terrible at estimating speeds and distances. I'm confident enough in my driving ability and safety to have an impartial record of my actions prior to any accident. I'm looking forward to having a black box to support my statements in what otherwise might be a my-word-against-his situation.
Sorry; you've read the 'facts' wrong. Incidentally, the front page Slashdot blurb doesn't count as factual material.
Sometimes it's a good idea to read the actual judgement in the case. Google cache.
This comment excerpts a key point from the judgement. The 'idea' in question is a development that pertains directly to Brown's normal work duties. Further, he sent a memo to management in 1996 indicating that he had developed this idea into a workable method.
It looks a lot like he did a bit of extra work related to his job, and he's trying to shake down his former employers.
And he was right--you were at your workplace, using their equipment and their lab space. And the first person you told was the company CEO. If you want to do hardware development for yourself, sink ten or twenty thousand dollars into equipping your garage.
Yeah, the lawyers' attitude sucks, but their position isn't exactly unreasonable. For what it's worth, they probably would have let you have one for your own use.
On the other hand, if you designed radios at work, the factory would have a tenable legal and moral position if you suddenly decided to start building and selling radio equipment.
The key question here is whether or not there is a significant overlap between the programming duties of the employee in this case and his official work duties. Judging by some of the other posts (including excerpts from the judgement itself) there is evidence that this is not an entirely unfounded conclusion.