> Take a Project Gutenberg text file (or any text file), throw it into your favorite word > processor/page layout program, choose a nice body font, give it some reasonable margins, > stick page # footers in, then export it all out to a PDF. Fire up Acrobat Reader, set the > background color to a nice cream color, rotate the page 90 degrees, hit fullscreen...
Seems like a lot of wasted effort. Why not just use xrandr to rotate the display?
And that agreement need not mention what you intend to do with the code, though you might want to give them a seperate letter promising to release the code as Free Software and to give them credit for supporting the initial development.
I think you are right that a negative mass would accelerate in the opposite direction from an applied force, but in general relativity gravitation is not a force field, it is curvature of space. I'm not about to try to solve the field equations, but I think that it is reasonable to assume that negative mass would accelerate away from positive mass. Think of the rubber-sheet analogy, with the negative masses dimpling the sheet upward instead of downward like the positive masses.
First let's consider the simple case of a 1 ton positve mass and a 1 ton negative mass placed at rest 100m apart in an empty universe. I agree that under your classical gravitation model the result will be as you say: both masses go shooting off in the direction of the positive mass. Very strange.
Under GR, however, the masses will behave as one might expect: the two masses accelerate off in opposite directions.
Now let's add the rod, but let's use a simple one: equal electric charges on each mass sufficient to exactly equal the gravitational "force" between the masses.
Consider the case where the charges are both positive (or both negative). For your classical model the result is the same as with no charge but twice as fast: the positive mass is accelerated away from the negative mass by both the gravitational and electric fields, while the the negative mass reacts to both forces in its contrary way and follows. Both energy and momentum are conserved.
For the GR model the positive mass behaves as above but the negative mass is accelerated away from positive mass by gravity and toward it by the reversed force of the electric field. As a result, it stands still. Energy is conserved because the acceleration of the positive mass is at the expense of gravitational and electrical potential energy, but we seem to have a momentum problem.
Now to the "rod": make the charge on one mass positive and the other negative.
For both models the positive mass will stand still as the gravitational and electric forces on it balance. For the classical model the negative mass also stands still as both forces are reversed and therefor still balance. For the GR model the negative mass accelerates away under the force of negative gravity and reversed electrostatic attraction. The negative mass acquires negative energy as it goes, balanced by the increase in electrical and gravitational potential energy. We still have a momentum problem, however.
As we must at all costs avoid offending Emmy Noether, it looks like Newton wins this one.
> For example, if you had a one ton ball of "regular" matter and a -1 ton ball of this > "negative" matter, and were to hook them together on a fixed rod you basically would've > constructed a perpetual motion "engine" that would accelerate along the axis of that rod > without any expenditure of energy.
That would no more produce acceleration than would the same experiment done with positive and negative electric charges. The two gravitational charges will just repel each other, producing tension in the rod.
Because as everyone knows, Iran has absolutely no communication links but that one cable: no radio, no satellite links, no buried cable into neigboring nations: just that one single undersea fiber-optic cable.
The judge decides whether or not he will grant the motion. Of course, even if he grants the motion the defendant's counterclaims will remain. A lawsuit doesn't end just because the plaintiff drops its claims. It's easier to get into court than it is to get out again.
The US could shoot it (and probably hit it on the first try...) but the US could no more shoot it _down_ than the Chinese could. Hitting it with an anti-satellite missile would just bust it into pieces about the same size as the ones it will break up into when it hits the upper atmosphere. Just as much stuff would hit the ground but less predictably.
It can be shown that statistically double-insulated products with two-wire cords are at least as safe as those with three-wire cords and grounded frames. There are wiring errors that can result in the frame of the three-wire device being hot. The double-insulated products are not necessarily cheaper: the cost of the extra insulation can equal or exceed the cost of the ground wire and plug. However, since no part you can touch is connected to any wire in the cord, you can't get a shock no matter how screwed up your wiring is.
Since the problem evidently only shows up in Britain I think I know what happened. There is some capacitive coupling between the hot side of the line and the metal case but at 120V it does not pass enough current to be perceptible or to fail UL requirements. At 240V, however, the current is perceptible. Poor design. I'm sure these things are made in China. Are they designed there as well?
> Actually, it totally depends on your local electrical system.
In the US ground is tied to earth at the service entrance, as is the neutral. Ground and neutral are connected together nowhere else. The service from the utility does not include a ground: just neutral and two 120V lines (240V between them). The utility's neutral is grounded at the transformer.
> I'm sure there is variation within the US too.
I don't believe that there are any jurisdictions in the US that have not adopted the National Electrical Code.
The problem described in the article, if it actually exists, is due to coupling (metallic or capacitive) between the AC line and the metal exterior. It has to do with the absence of a third pin only in that if there was a third pin the metal exterior would be connected to it and therefor could not be hot. There are many double-insulated appliances with two-wire cords and metal exteriors that do not give shocks.
> I find it very hard to explain to people (even those who should be able to understand) > that I copyright my material *because* I want to distribute it free of charge.
Actually, you "copyright' your material because you have no choice. Copyright happens automatically at the time the work is fixed into tangible form whether you like it or not. You can place a "public domain" notice on all copies you distribute but even that may not be completely effective due to things like "rights of reversion" and "moral rights".
Slashdot Mirror
There is no significant difference between the MIT license and the modified BSD license.
> There would effectively be no software...
All the software I use would still be available. So would most closed-source software: most does not come from the "larger software companies".
> Take a Project Gutenberg text file (or any text file), throw it into your favorite word
> processor/page layout program, choose a nice body font, give it some reasonable margins,
> stick page # footers in, then export it all out to a PDF. Fire up Acrobat Reader, set the
> background color to a nice cream color, rotate the page 90 degrees, hit fullscreen...
Seems like a lot of wasted effort. Why not just use xrandr to rotate the display?
> If vendors would be responsible for their faulty software there wouldn't be any of the
> larger software companies around anymore.
And this would be a bad thing why?
"Stuff That Matters", remember?
> They seem to be going on the assumption that if someone uses Facebook, they really have
> no privacy concerns.
Sounds like a reasonable assumption to me.
> Do Facebook users deserve privacy?
Sure. And they can have it. All they need to do is keep the stuff that they want to remain private off Facebook.
And that agreement need not mention what you intend to do with the code, though you might want to give them a seperate letter promising to release the code as Free Software and to give them credit for supporting the initial development.
A positve test mass.
Now consider an Earth with negative mass and place a small test mass in orbit around it.
I think you are right that a negative mass would accelerate in the opposite direction from an applied force, but in general relativity gravitation is not a force field, it is curvature of space. I'm not about to try to solve the field equations, but I think that it is reasonable to assume that negative mass would accelerate away from positive mass. Think of the rubber-sheet analogy, with the negative masses dimpling the sheet upward instead of downward like the positive masses.
First let's consider the simple case of a 1 ton positve mass and a 1 ton negative mass placed at rest 100m apart in an empty universe. I agree that under your classical gravitation model the result will be as you say: both masses go shooting off in the direction of the positive mass. Very strange.
Under GR, however, the masses will behave as one might expect: the two masses accelerate off in opposite directions.
Now let's add the rod, but let's use a simple one: equal electric charges on each mass sufficient to exactly equal the gravitational "force" between the masses.
Consider the case where the charges are both positive (or both negative). For your classical model the result is the same as with no charge but twice as fast: the positive mass is accelerated away from the negative mass by both the gravitational and electric fields, while the the negative mass reacts to both forces in its contrary way and follows.
Both energy and momentum are conserved.
For the GR model the positive mass behaves as above but the negative mass is accelerated away from positive mass by gravity and toward it by the reversed force of the electric field. As a result, it stands still. Energy is conserved because the acceleration of the positive mass is at the expense of gravitational and electrical potential energy, but we seem to have a momentum problem.
Now to the "rod": make the charge on one mass positive and the other negative.
For both models the positive mass will stand still as the gravitational and electric forces on it balance. For the classical model the negative mass also stands still as both forces are reversed and therefor still balance. For the GR model the negative mass accelerates away under the force of negative gravity and reversed electrostatic attraction. The negative mass acquires negative energy as it goes, balanced by the increase in electrical and gravitational potential energy. We still have a momentum problem, however.
As we must at all costs avoid offending Emmy Noether, it looks like Newton wins this one.
> For example, if you had a one ton ball of "regular" matter and a -1 ton ball of this
> "negative" matter, and were to hook them together on a fixed rod you basically would've
> constructed a perpetual motion "engine" that would accelerate along the axis of that rod
> without any expenditure of energy.
That would no more produce acceleration than would the same experiment done with positive and negative electric charges. The two gravitational charges will just repel each other, producing tension in the rod.
Because as everyone knows, Iran has absolutely no communication links but that one cable: no radio, no satellite links, no buried cable into neigboring nations: just that one single undersea fiber-optic cable.
Right.
> The US Department of Justice has extended its anti-trust oversight of Microsoft by two
> years.
No they didn't. US Federal District Judge Colleen Kollar-Kotelly did.
The judge decides whether or not he will grant the motion. Of course, even if he grants the motion the defendant's counterclaims will remain. A lawsuit doesn't end just because the plaintiff drops its claims. It's easier to get into court than it is to get out again.
> 'makers of burglary kits' who have made 'a thieves' charter' to steal money from the
> music industry.
Sure looks like libel to me.
The US could shoot it (and probably hit it on the first try...) but the US could no more shoot it _down_ than the Chinese could. Hitting it with an anti-satellite missile would just bust it into pieces about the same size as the ones it will break up into when it hits the upper atmosphere. Just as much stuff would hit the ground but less predictably.
I remember when it was $.35/gallon. However, that was more than $1.00/gallon when adjusted for inflation.
But I forget: this is Slashdot.
Hint: the process does not use corn.
Which lobbies, precisely?
"LIGO Detects Absence Of Gravity Waves" would be more accurate.
"LIGO Establishes Absence Of Gravity Waves Above Its Detection Threshold From A GRB" would be more accurate yet but too long for a headline.
"earthed" is British for "grounded".
It can be shown that statistically double-insulated products with two-wire cords are at least as safe as those with three-wire cords and grounded frames. There are wiring errors that can result in the frame of the three-wire device being hot. The double-insulated products are not necessarily cheaper: the cost of the extra insulation can equal or exceed the cost of the ground wire and plug. However, since no part you can touch is connected to any wire in the cord, you can't get a shock no matter how screwed up your wiring is.
Since the problem evidently only shows up in Britain I think I know what happened. There is some capacitive coupling between the hot side of the line and the metal case but at 120V it does not pass enough current to be perceptible or to fail UL requirements. At 240V, however, the current is perceptible. Poor design. I'm sure these things are made in China. Are they designed there as well?
> Actually, it totally depends on your local electrical system.
In the US ground is tied to earth at the service entrance, as is the neutral. Ground and neutral are connected together nowhere else. The service from the utility does not include a ground: just neutral and two 120V lines (240V between them). The utility's neutral is grounded at the transformer.
> I'm sure there is variation within the US too.
I don't believe that there are any jurisdictions in the US that have not adopted the National Electrical Code.
The problem described in the article, if it actually exists, is due to coupling (metallic or capacitive) between the AC line and the metal exterior. It has to do with the absence of a third pin only in that if there was a third pin the metal exterior would be connected to it and therefor could not be hot. There are many double-insulated appliances with two-wire cords and metal exteriors that do not give shocks.
> what-is-this-privacy-of-which-you-speak
It's clear that the university president is an asshole, but what the hell has this to do with privacy? Perhaps you meant to type "freedom of speech"?
> I find it very hard to explain to people (even those who should be able to understand)
> that I copyright my material *because* I want to distribute it free of charge.
Actually, you "copyright' your material because you have no choice. Copyright happens automatically at the time the work is fixed into tangible form whether you like it or not. You can place a "public domain" notice on all copies you distribute but even that may not be completely effective due to things like "rights of reversion" and "moral rights".