If two magnets get close enough and snap together are they violating conservation of momentum when forces are acting on them to accelerate toward each other?
Of course not. The total momentum of the system stays zero.
When I was a kid, I tried to make a self-propelled car by putting magnets on the back and front bumpers of a toy car, reasoning that the front magnet would attract the back one, and therefore produce thrust. When I built it, I learned a valuable lesson: it doesn't work. Because the force pulling the back magnet forward is exactly counterbalanced by the force pulling the front magnet backward.
The EM drive is closely analagous to this idea. Except that they didn't figure out when they were eight that this will never work.
I see you like to comment on something without reading it.... try taking a look at the article... it says specifically that conservation of momentum is NOT violated...
Well, the article says it, so it must be true.
If you're not throwing anything out of the back of the rocket, you're violating conservation of momentum.
In Dr. White’s model, the propellant ions of the MagnetoHydroDynamics drive are replaced as the fuel source by the virtual particles of the Quantum Vacuum, eliminating the need to carry propellant.
Let's see: we can violate conservation of momentum by invoking some sort of vaguely defined quantum woo. Riiiight. Where do I send my check?
Car analogy time: Mozilla wants everyone to use paved roads so car drivers can see hazards more effectively.
Continued car analogy: Mozilla, to this end, builds a car that shuts down when you try to drive it on a dirt road. Why would anybody want to buy a car that did that?
You almost got the message correctly. The right message is no should ever develop for mozilla, or chrome, or internet explorer, or opera, or any other browser in particular. Developers should be able to develop using standards, and the browsers should correctly display content based on standards.
Mozilla thinks my web browser should break sites that I choose to visit because they don't like it? I'm all for https, and I run Https Everywhere as a plugin. But it's batshit crazy for somebody to try to force this through the browser. Mozilla has been going downhill fast, but this is really the end.
To force others into squalor because you don't want to sell them your resource (at fair cost), is not just immoral but unethical as well. [...] All you selfish twits need to pull your heads out of your asses and look at the life you live. You are not independent, you need the rest of us and some of those people need the water to give you what you want.
So, instead, you believe you're entitled expect the Great Lakes states (not to mention Canada) to destroy their local ecosystems because you want to have a bunch of golf courses and almond farms in the middle of a fucking desert?
What this would amount to in practice is tapping the Great Lakes to enable unsustainable development in the Southwest. This would be an ecological disaster for both the Great Lakes, which are already losing volume due to climate change, and the Southwest, which has been unsustainably developed for decades.
How about, instead of massive engineering projects, we just don't build cities where there aren't enough natural resources to sustain them?
The problem with that is that this device and insurance in general doesn't factor in driver ability. Sure I brake harder and later than the general driving population and I corner like my car is on rails. But 1) I actually have a decent amount of race track experience where I actually AM controlling the car at the absolute limits, 2) I never come close to those limits on the street, 3) I maintain my car significantly better than the average vehicle on the road, 4) I have far better tires than the average vehicle on the road, and 5) I have a much lighter and easier to control car [Miata WOOHOO] than the average car on the road.
However none of my 5 points factor in on insurance. Why would I let them track me to see that my car brakes harder and corners faster than the average car if they won't factor in the driving abilities and vehicular factors that make me safer than the average driver?
The belief that increasing skill would reduce crash rates has seemed to many too obvious to be worth investigating. Such a belief reinforces the view that driver education must increase safety, even in the face of so much evidence that it does not (Chapter 8). It is widely held by driving aficionados that high-skill drivers are inherently safe drivers.
This was examined directly by comparing the on-the-road driving records of unusually skilled drivers to the records of average drivers. The investigators obtained the names and addresses of national competition license holders from the Sports Car Club of America. They compared the on-the-road driving records of these license holders (referred to in their paper as racing drivers) in Florida, New York, and Texas, to comparison groups of drivers in the same states matched in such characteristics as gender and age.
The results of the study are summarized in Fig. 9-1, which displays the violation and crash rates for the racing drivers divided by the corresponding rates for the comparison drivers. If there were no differences between the groups of drivers, these ratios would all be close to one, whereas if the racing drivers had lower rates, the ratios would be less than one. What is found is that in all 12 combinations examined, the rates for the racing drivers exceeded those for the comparison drivers, in most cases by considerable amounts. Thus, on a per year basis, the racing drivers not only had substantially more violations, especially speeding violations, but also more crashes.
This is supported for me anecotally: I have several friends who spend a lot of time on the track, and are highly skilled drivers. They all drive like total assholes on the public roads.
Se we should all be mindless sheeple who accelerate so slowly you get passed by a scooter, and corner so peacefully that the keychain barely moves away form vertical?
The insurance industry is suggesting we all drive like scared 80 year olds?
I'd rather die or just give the fuck up and get a driverless car.
Fine with me, as long as you don't whinge about other people getting lower insurance rates.
Is someone who briskly takes off from a light -- not doing burnouts or other kinds of hooning, -- automatically less safe than someone who rolls out at snails' pace?
Is someone who goes around a corner with some amount of G automatically less safe than those who take forever to negotiate the same corner?
Do you think insurance companies are a bunch of idiots who just make this shit up? No, they've done extensive studies of the correlations between particular driver behaviors and insurance costs, and guess what: these sorts of behaviors are strongly correlated with higher insurance costs. For example, they're twice as predictive as using points on your license.
It has to be better than that, though. The would-be killers need to be shot down, and then the MPs need to pose the very dead Obi Wannabe Jihaddi next to a 12 year old girl holding a shotgun and smiling.
Even better, how about a video of Obi being beheaded with a knife? Nobody's thought of that one before.
yes, I'm sure she worked in complete isolation, and developed everything by herself.
No, she was a part of a group consisting entirely of women under the management of Edward Pickering at Harvard Observatory, called at the time "Pickering's Harem" Despite her groundbreaking accomplishments, Leavitt was unable to obtain a faculty position at Harvard, entirely due to her gender.
Times have changed a lot since then, despite the efforts of ignorant douchebags like you.
Well, here's where you open yourself up. Distance measurements benefit from longer baselines. The biggest one we have now is about 2AU wide. Take a picture now, wait 6 months, take a picture again when the earth is on the opposite side of the sun. If we have a base on mars, we can have a slightly wider baseline with earth and mars on opposite sides of the sun for a simultaneous measurement (can't do that now at all) and two martian orbital radii for non-simulataneous measurements about a year apart.
Now you might say: well why can't we do this with a remote probe?
We are: It's called Gaia. The baseline isn't really the limiting factor, nor is mirror size: it's mostly about atmospheric distortion and instrument stability, both of which are vastly improved in space. Gaia will be able to do parallaxes to accuracy of 20 micro-arcseconds.
A lot of his work was good, and even his weaker stuff is still worth a read -- some neat stuff explored; but your definitely looking through a window into Heinlein's political, economic, and sexual ideology and it becomes apparent to the point of being an annoying distraction.
The thing that stood out for me re-reading Mistress recently was that Heinlein was an utter troglodyte about gender roles. He was progressive for his time, but his treatment of women really stands out, and not in a good way, when reading his books with a modern sensibility.
Because there is a consensus that widespread adoption of solar power is a net good for the society as a whole.
And they're unwilling to pay for it with their own money.
Government's money is our money. We get to vote on how it's used. If I believe that subsidizing an activity undertaken by someone else is to my benefit, I will vote to do so. This is me choosing how to use my own money.
Oh, wait: you must be a Libertarian, and therefore think that you as an individual have a personal veto over everything the government might decide to do. Never mind.
Why do artists expect to be paid at all for recordings of their music? For a very brief period in history, making money off of recordings was made possible by a coincidental combination of technology and artificial scarcity caused by the cumbersome nature of physical media. Before the advent of physical recordings, musicians had to make money by performing. After the advent of digital recordings, musicians will once again have to make money by performing. Anything else will prove to have been historically anomalous.
Making and distributing recordings will still be in artists' interest, because they will serve as a way to generate demand for performances. That is, recordings will become a form of advertising, which will be distributed for all intents and purposes for free, or even at the expense of artists.
Can we quit wringing our hands about this now? Art will survive just fine.
To be clear, I (parent AC) wasn't saying that the probability distribution is the wave function, just that it is given by it (which you confirm, it is the square of the amplitude). Now consider you make an observation and collapse the system to a single state. This state had a certain probability of occurring (again, given by the wave function). If you try to measure again, you will get the same state.
Only if you don't observe any orthogonal characteristics in the meantime. Consider a two-state system, with eigenstates |a> and |b> (for example, z-spin). Now consider an orthogonal basis |1> and |2> (for example, x-spin) which spans the same Hilbert space, such that
Now, suppose we observe the system to be in state |a>. Then if we perform an observation in the orthogonal basis, we will have a 50% probability to be in state |1> and 50% in state |2>. Suppose it's in state |2>. Now if we observe the first basis again, it's not in state |a> with certainty any more, despite the fact that we just measured it. It has a 50% chance to be in |a> and 50% to be in |b>.
There is no necessity to "restore coherence": the system is fully coherent throughout. This behavior does not happen with coins.
Slashdot Mirror
If two magnets get close enough and snap together are they violating conservation of momentum when forces are acting on them to accelerate toward each other?
Of course not. The total momentum of the system stays zero.
When I was a kid, I tried to make a self-propelled car by putting magnets on the back and front bumpers of a toy car, reasoning that the front magnet would attract the back one, and therefore produce thrust. When I built it, I learned a valuable lesson: it doesn't work. Because the force pulling the back magnet forward is exactly counterbalanced by the force pulling the front magnet backward.
The EM drive is closely analagous to this idea. Except that they didn't figure out when they were eight that this will never work.
I see you like to comment on something without reading it.... try taking a look at the article... it says specifically that conservation of momentum is NOT violated...
Well, the article says it, so it must be true.
If you're not throwing anything out of the back of the rocket, you're violating conservation of momentum.
In Dr. White’s model, the propellant ions of the MagnetoHydroDynamics drive are replaced as the fuel source by the virtual particles of the Quantum Vacuum, eliminating the need to carry propellant.
Let's see: we can violate conservation of momentum by invoking some sort of vaguely defined quantum woo. Riiiight. Where do I send my check?
Car analogy time: Mozilla wants everyone to use paved roads so car drivers can see hazards more effectively.
Continued car analogy: Mozilla, to this end, builds a car that shuts down when you try to drive it on a dirt road. Why would anybody want to buy a car that did that?
Thanks, Mozilla, for yet another reason to stop using Firefox.
You'd think that they would take a hint from their declining usage, instead of doing crazier and crazier shit.
You almost got the message correctly. The right message is no should ever develop for mozilla, or chrome, or internet explorer, or opera, or any other browser in particular. Developers should be able to develop using standards, and the browsers should correctly display content based on standards.
So ... when did http cease to be a standard?
Mozilla thinks my web browser should break sites that I choose to visit because they don't like it? I'm all for https, and I run Https Everywhere as a plugin. But it's batshit crazy for somebody to try to force this through the browser. Mozilla has been going downhill fast, but this is really the end.
Three words: Fuck you, Mozilla.
If someone plagiarized whole paragraphs without citations, they get an incomplete and need to do a rewrite.
Really? Somebody who plagiarizes whole paragraphs without citations should be thrown out of school.
...rant...
This is either a masterful troll, or parent doesn't have the slightest sense of irony whatsoever.
To force others into squalor because you don't want to sell them your resource (at fair cost), is not just immoral but unethical as well.
[...]
All you selfish twits need to pull your heads out of your asses and look at the life you live. You are not independent, you need the rest of us and some of those people need the water to give you what you want.
So, instead, you believe you're entitled expect the Great Lakes states (not to mention Canada) to destroy their local ecosystems because you want to have a bunch of golf courses and almond farms in the middle of a fucking desert?
Good luck with that.
Worst. Idea. Ever.
What this would amount to in practice is tapping the Great Lakes to enable unsustainable development in the Southwest. This would be an ecological disaster for both the Great Lakes, which are already losing volume due to climate change, and the Southwest, which has been unsustainably developed for decades.
How about, instead of massive engineering projects, we just don't build cities where there aren't enough natural resources to sustain them?
It's a war, I tell you, a war on frequentists! I'm 95% certain!
The problem with that is that this device and insurance in general doesn't factor in driver ability. Sure I brake harder and later than the general driving population and I corner like my car is on rails. But 1) I actually have a decent amount of race track experience where I actually AM controlling the car at the absolute limits, 2) I never come close to those limits on the street, 3) I maintain my car significantly better than the average vehicle on the road, 4) I have far better tires than the average vehicle on the road, and 5) I have a much lighter and easier to control car [Miata WOOHOO] than the average car on the road.
However none of my 5 points factor in on insurance. Why would I let them track me to see that my car brakes harder and corners faster than the average car if they won't factor in the driving abilities and vehicular factors that make me safer than the average driver?
From this study summary:
The belief that increasing skill would reduce crash rates has seemed to many too obvious to be worth investigating. Such a belief reinforces the view that driver education must increase safety, even in the face of so much evidence that it does not (Chapter 8). It is widely held by driving aficionados that high-skill drivers are inherently safe drivers.
This was examined directly by comparing the on-the-road driving records of unusually skilled drivers to the records of average drivers. The investigators obtained the names and addresses of national competition license holders from the Sports Car Club of America. They compared the on-the-road driving records of these license holders (referred to in their paper as racing drivers) in Florida, New York, and Texas, to comparison groups of drivers in the same states matched in such characteristics as gender and age.
The results of the study are summarized in Fig. 9-1, which displays the violation and crash rates for the racing drivers divided by the corresponding rates for the comparison drivers. If there were no differences between the groups of drivers, these ratios would all be close to one, whereas if the racing drivers had lower rates, the ratios would be less than one. What is found is that in all 12 combinations examined, the rates for the racing drivers exceeded those for the comparison drivers, in most cases by considerable amounts. Thus, on a per year basis, the racing drivers not only had substantially more violations, especially speeding violations, but also more crashes.
This is supported for me anecotally: I have several friends who spend a lot of time on the track, and are highly skilled drivers. They all drive like total assholes on the public roads.
Se we should all be mindless sheeple who accelerate so slowly you get passed by a scooter, and corner so peacefully that the keychain barely moves away form vertical?
The insurance industry is suggesting we all drive like scared 80 year olds?
I'd rather die or just give the fuck up and get a driverless car.
Fine with me, as long as you don't whinge about other people getting lower insurance rates.
Is someone who briskly takes off from a light -- not doing burnouts or other kinds of hooning, -- automatically less safe than someone who rolls out at snails' pace?
Is someone who goes around a corner with some amount of G automatically less safe than those who take forever to negotiate the same corner?
Do you think insurance companies are a bunch of idiots who just make this shit up? No, they've done extensive studies of the correlations between particular driver behaviors and insurance costs, and guess what: these sorts of behaviors are strongly correlated with higher insurance costs. For example, they're twice as predictive as using points on your license.
It has to be better than that, though. The would-be killers need to be shot down, and then the MPs need to pose the very dead Obi Wannabe Jihaddi next to a 12 year old girl holding a shotgun and smiling.
Even better, how about a video of Obi being beheaded with a knife? Nobody's thought of that one before.
yes, I'm sure she worked in complete isolation, and developed everything by herself.
No, she was a part of a group consisting entirely of women under the management of Edward Pickering at Harvard Observatory, called at the time "Pickering's Harem" Despite her groundbreaking accomplishments, Leavitt was unable to obtain a faculty position at Harvard, entirely due to her gender.
Times have changed a lot since then, despite the efforts of ignorant douchebags like you.
Well, here's where you open yourself up. Distance measurements benefit from longer baselines. The biggest one we have now is about 2AU wide. Take a picture now, wait 6 months, take a picture again when the earth is on the opposite side of the sun. If we have a base on mars, we can have a slightly wider baseline with earth and mars on opposite sides of the sun for a simultaneous measurement (can't do that now at all) and two martian orbital radii for non-simulataneous measurements about a year apart.
Now you might say: well why can't we do this with a remote probe?
We are: It's called Gaia. The baseline isn't really the limiting factor, nor is mirror size: it's mostly about atmospheric distortion and instrument stability, both of which are vastly improved in space. Gaia will be able to do parallaxes to accuracy of 20 micro-arcseconds.
A lot of his work was good, and even his weaker stuff is still worth a read -- some neat stuff explored; but your definitely looking through a window into Heinlein's political, economic, and sexual ideology and it becomes apparent to the point of being an annoying distraction.
The thing that stood out for me re-reading Mistress recently was that Heinlein was an utter troglodyte about gender roles. He was progressive for his time, but his treatment of women really stands out, and not in a good way, when reading his books with a modern sensibility.
(And how many more pointless discussions could be avoided if everyone knew "per se" = "by itself".)
Not to mention that the phrase is toe the line.
Because there is a consensus that widespread adoption of solar power is a net good for the society as a whole.
And they're unwilling to pay for it with their own money.
Government's money is our money. We get to vote on how it's used. If I believe that subsidizing an activity undertaken by someone else is to my benefit, I will vote to do so. This is me choosing how to use my own money.
Oh, wait: you must be a Libertarian, and therefore think that you as an individual have a personal veto over everything the government might decide to do. Never mind.
Regarding the incentives (tax credits and the like), again, once solar hits some critical mass, why would the government provide incentives?
Because there is a consensus that widespread adoption of solar power is a net good for the society as a whole.
Why do artists expect to be paid at all for recordings of their music? For a very brief period in history, making money off of recordings was made possible by a coincidental combination of technology and artificial scarcity caused by the cumbersome nature of physical media. Before the advent of physical recordings, musicians had to make money by performing. After the advent of digital recordings, musicians will once again have to make money by performing. Anything else will prove to have been historically anomalous.
Making and distributing recordings will still be in artists' interest, because they will serve as a way to generate demand for performances. That is, recordings will become a form of advertising, which will be distributed for all intents and purposes for free, or even at the expense of artists.
Can we quit wringing our hands about this now? Art will survive just fine.
What climate mess?
I am convinced that the primary reason Bill Nye thinks that tech people tend to be scientifically illiterate is that he reads
Slashdot.
To be clear, I (parent AC) wasn't saying that the probability distribution is the wave function, just that it is given by it (which you confirm, it is the square of the amplitude). Now consider you make an observation and collapse the system to a single state. This state had a certain probability of occurring (again, given by the wave function). If you try to measure again, you will get the same state.
Only if you don't observe any orthogonal characteristics in the meantime. Consider a two-state system, with eigenstates |a> and |b> (for example, z-spin). Now consider an orthogonal basis |1> and |2> (for example, x-spin) which spans the same Hilbert space, such that
|1> = 1/\srqrt{2} |a> + 1/\sqrt{2} |b>
|2> = 1/\sqrt{2} |a> - 1/\sqrt{2} |b>
Now, suppose we observe the system to be in state |a>. Then if we perform an observation in the orthogonal basis, we will have a 50% probability to be in state |1> and 50% in state |2>. Suppose it's in state |2>. Now if we observe the first basis again, it's not in state |a> with certainty any more, despite the fact that we just measured it. It has a 50% chance to be in |a> and 50% to be in |b>.
There is no necessity to "restore coherence": the system is fully coherent throughout. This behavior does not happen with coins.