You can quite easily contain the field from the magnets with a piece of iron. You could also pack the magnets in opposite directions so that any residual field from one magnet cancels the field from another.
If they are packed properly, I don't see why it should be a problem for a compass even if it is right next to the crate of magnets.
I agree that you would need to check that the compass is pointing in the correct direction before taking off (which is presumably standard procedure anyway). The compass being affected is certainly a lot more obvious then electrical interference so less of a danger. It would seem sensible to warn the pilot though to make sure he checks for any problems.
It sounds to me that the captain reacted violently before checking if the cargo was actually dangerous. If there was any danger then I think it should be obvious before taking off (the magnet pointing at the crate and not north).
There seems to be a lot of irrational, unscientific behavior when it comes to interference and flying. Electrical interference is well understood physically. It should be easy to generate fields at a range of frequencies in a range of positions inside the cabin to test what is safe and what is not. That way we could have rules surrounding electronics based on real threat, not superstition. TFA article mentions that interference has been blamed for a recent accident but not any tests like this being done or any measures to shield the planes (if a mouse is enough to endanger a plane then making sure no one carries anything dangerous is obviously isn't going to work).
Unfortunately magnets are not able to induce a current in wires/other electronics simply by being close to them. (If they did we wouldn't have to worry about where our energy is going to come from or global warming, we'd just use magical perpetual motion machines made out of magnets and wires).
The magnetic field needs to be varying (AC driven electro magnet) or the wire needs to be moving relative to the magnet. A crate of magnets sitting below a bunch of electronics is fine.
If the electronics included a hard drive then that would be different (it would still have to be very very strong magnets). A quick check of wikipedia shows that the first hard drive was introduced 3 years before the last DC-6 was produced so I doubt that is a problem.
Searching for the Higgs boson (the particle that the media are talking about when they say God particle) has nothing to do with God.
I have never heard another physicist refer to it as the god particle (except when satirising media articles on the subject). It is an unfortunate expression and I don't like it.
The Higgs boson is an important part of a theory called the Standard Model, our best theory of the interactions of fundamental particles. It is the last fundamental particle in this theory left to be discovered and is an integral part of it. Looking for the Higgs is about understanding nature at its most fundamental level and I think that makes it worthwhile. The LHC is aiming to find or disprove the existence of the Higgs and explore other new physics. There is also a huge amount of spin out technology which comes from it which is also useful (although I am far less interested in that).
If you are interested in what the LHC is for have a look at CERN's FAQ or wikipedia .
The article is actually just talking about the PCs used to store ALICE's data.
The data analysis for the LHC experiments uses the LHC Computing Grid . The analysis is spread out between different sites (exactly what happens at which sites depends on the experiment). The PCs which make up the grid though are largely (fom what I have seen) Dell PCs.
Data analysis for particle physics is highly parallelisable (large number of events, on which you want to run the same analysis) so large numbers of inexpensive computers makes more sense than super computers.
I am no expert on stats but I think you are confusing standard deviations. The SD of the IQ of the population of the world is (as you say) supposed to be 15 (by design). The standard deviation you need to calculate the standard error of their measurement is the standard deviation of the distribution of results of a measurement of a particular person's IQ (ie the square root of the mean square difference between their true IQ and the result of the test).
To work this out, you could:
Construct a sample of people who you believe to be identical using the results of other tests.
Take a number of independent measurements of the IQ of these people (using the same IQ test as is used for the study).
Use the standard deviation of the results as an estimator and the standard deviation of the probability distribution of the results for your test.
You could assume that this distribution is the same for everyone and then divide this standard deviation by the square root of the number of people in each group to get a standard error for each group.
I am sure this method has problems but it is only an example.
In practice, for a decent test, the standard deviation of the results for a person with a given IQ should be much less than 15 and so I think your conclusion still applies.
"Either he gets the sex or he offends the other partly so badly that he never hears from him again."
I don't think there is any question about it.
If someone demanded a night with your sister or cousin in exchange for fixing your car or decorating your house you would be pretty pissed. Especially if they did so "as brazenly and obnoxiously as possible".
Actually isotropy means that it looks the same in every direction (there is no favoured direction). Homogeneity means that it is the same everywhere (there is no favoured point). The universe is thought to be both isotropic and homogenous.
I am not sure exactly what you mean about the absolute reference point/frame. The equivalence of all inertial reference frames in special relativity is referring to physical measurements/results being equivalent for all observers who are not accelerating. I am not sure how a point like the centre of the universe would mess this up. I would be interested to know if I am missing something though.
In the UK lots of parents didn't let doctors give it to their kids because of scare stories about link between it and autism (which has been shown to not exist). It is the low uptake of the vacine (which is not very effective and so needs near 100% uptake to prevent outbreaks) which is causing cases here. I think that the resurgence of mumps in the UK is a completely different issue to the growing numbers of cases of dieseses like rickets here and abroad. Mumps outbreaks here are simply a result of irresponsible scare mongering by the british tabloids.
None of the satellites you have mentioned are designed completely by students. Express is not based on any designs made by professionals like CubeSats are.
3 of them are being carried on Express. Unfortunately CubeSats are not really designed by students like SSETI's satellites, their critical sub-systems are based heavily on a design done by professionals. They are not nearly as interesting.
I am actually working on a satellite being built by teams of students distributed at different universities at them moment. One of the things we will be doing is launching a box of hardware that people seem to disagree over whether it will work in space. We will test this hardware during flight and are measuring other parameters like total ionising dose and the plasma current. Hopefully this will make what we are doing cheaper next time because we will be able to use lots of off the shelf hardware that we did not know would work this time.
Our orbit will pass through the Van Allen belts so this is about as much of a torture test as you can get.
The above described business plan is covered by business practice patent #123987 held by me. Any attempt to use this idea to make money would infringe and would force me to sue you. Business is definitely booming!
I can't believe this made it onto the front page. The guy who wrote this is a raving loony. He makes Ayn Rand look like a communist. (read some of his other articles here ) I find it difficult to take seriously the opinions of someone who believes that justice should be privatised.
Of course there is going to be lower prices where Microsoft is competing. If you have to compete with someone who breaks all the rules it is hard. One of the things you are going to have to do is lower prices.
Microsoft is a large company. If you are competing with them then you are facing a lot of competition (a significant proportion of the total marketing budget for the whole software industry is Microsoft's) so of course there is more pressure on you to lower prices.
"First, in a poll of adult computer users taken by USA Today, only 6 percent said that "reducing Microsoft's influence" was a "major issue" to them. Most consumers love Microsoft's products. " As much as 6% of computer users think reducing Microsoft's influence is important? In other words most people who have actually used a computer that is not running Microsoft software (windows) think Microsoft is a bad thing, so bad in fact that reducing their influence is a "major issue". Hardly anyone thinks reducing Esso's influence in the oil market is a major issue but there is a whole campaign to boycott them, people hate Esso. Sounds like people hate Microsoft's products to me.
Just because prices fall because a company exists it doesn't make it good. It is well known that companies with too much market power lower prices to squeeze out competition so they can raise prices later and stop innovating (predatory pricing). This is a problem where there are barriers to entry in a market. Computer software has some of the highest barriers to entry of any market. You have to spend almost all of your costs (development costs) before you make a cent and there are proprietary standards that mean it is very hard to compete with an established rival since everything uses there standard.
This guy actually doesn't believe in market failure. Of course he thinks anti-trust laws are bad.
Quantum encryption may not be as hard to crack as people think. Firstly there is the problem that it relies on only one photon ever being transmitted at a time. You can easily reduce the power such that so few photons are transmitted that the probability of this happening is small but you can not ever eliminate the chance. Also the less power you have the more times no photon is transmitted at all and so the slower the connection. So in practice people will use enough power that there will be a small chance of obtaining the key (although this chance will be really really small if security is really important).
Assuming that it is unbreakable is dangerous. Quantum Theory while a very good theory is not the end of the story. The quantum systems people study to understand what is happening when a photon is emitted and transmitted through a optical fibber are also a simplification of what really happens and although the assumptions made are good ones there may be some subtle effect present that is only apparent when you solve a much more detailed (currently unsolvable) problem that more closely models reality. There may turn out to be away to crack it. No one can say for sure.
You might joke about the officials sense of humour but a British citizen was charged and given a prison sentence for joking to a friend about carrying a bomb while waiting to have her bag scanned (presumable for bombs or weapons) and her person scanned (for weapons) in the US. If they weren't listening in on her private conversation they wouldn't have had to get worried. Anyway doesn't america believe in freedom of speech? Doesn't locking someone up for something they said (to a friend) sort of conflict with that?
Almost all countries ask you to provide the address you are staying in if you enter them and are a foreign national (the main exception being EU countries if you are an EU citizen). This is regrettable but it is done by the authorities not a private corporation. They have a Privacy policy you can read. Also if you are staying at more than one place or don't know your address the customs officials will just say leave it blank or put the first address down, they are not interested in collecting a whole list of people you visit. It is totally different to a private company arbitrarily deciding that they want to collect detailed, personal information about you for the hell of it with no assurances about how they will use it (illegally I might add).
If I want to travel to the US I have to give them biometric data to be allowed into the country. They are already making it difficult for people to travel there (I heard about one high energy physicist that was not allowed to visit Fermilab for 2 weeks because of immigration checks). Because of their policy towards visitors, I would not visit the US unless I absolutely had to (professional reasons).
The US lawmakers don't usually let the fact that something is being done by somebody outside their boarders where it is perfectly legal stop them from claiming the person is breaking US law and trying to get them extradited. (DMCA claims against DVD Jon and that Australian crack author)
Despite not being given the chance to vote in the US (not being a US citizen) they seem to have decided that they have the juristiction to make laws that I have to follow while in the UK. The UK government also seems to have decided that it is ok for them to extradite me based on my violation of US law without a British judge having to agree (whithout demanding the same be applied to US citizens with regard to UK law) by making the Extradition Act law.
Slashdot Mirror
It really depends on how they are packed.
You can quite easily contain the field from the magnets with a piece of iron. You could also pack the magnets in opposite directions so that any residual field from one magnet cancels the field from another.
If they are packed properly, I don't see why it should be a problem for a compass even if it is right next to the crate of magnets.
I agree that you would need to check that the compass is pointing in the correct direction before taking off (which is presumably standard procedure anyway). The compass being affected is certainly a lot more obvious then electrical interference so less of a danger. It would seem sensible to warn the pilot though to make sure he checks for any problems.
It sounds to me that the captain reacted violently before checking if the cargo was actually dangerous. If there was any danger then I think it should be obvious before taking off (the magnet pointing at the crate and not north).
There seems to be a lot of irrational, unscientific behavior when it comes to interference and flying. Electrical interference is well understood physically. It should be easy to generate fields at a range of frequencies in a range of positions inside the cabin to test what is safe and what is not. That way we could have rules surrounding electronics based on real threat, not superstition. TFA article mentions that interference has been blamed for a recent accident but not any tests like this being done or any measures to shield the planes (if a mouse is enough to endanger a plane then making sure no one carries anything dangerous is obviously isn't going to work).
Unfortunately magnets are not able to induce a current in wires/other electronics simply by being close to them. (If they did we wouldn't have to worry about where our energy is going to come from or global warming, we'd just use magical perpetual motion machines made out of magnets and wires).
The magnetic field needs to be varying (AC driven electro magnet) or the wire needs to be moving relative to the magnet. A crate of magnets sitting below a bunch of electronics is fine.
If the electronics included a hard drive then that would be different (it would still have to be very very strong magnets). A quick check of wikipedia shows that the first hard drive was introduced 3 years before the last DC-6 was produced so I doubt that is a problem.
What? A Repetitive joke? On slashdot? Never!
I have never heard another physicist refer to it as the god particle (except when satirising media articles on the subject). It is an unfortunate expression and I don't like it.
The Higgs boson is an important part of a theory called the Standard Model, our best theory of the interactions of fundamental particles. It is the last fundamental particle in this theory left to be discovered and is an integral part of it. Looking for the Higgs is about understanding nature at its most fundamental level and I think that makes it worthwhile. The LHC is aiming to find or disprove the existence of the Higgs and explore other new physics. There is also a huge amount of spin out technology which comes from it which is also useful (although I am far less interested in that). If you are interested in what the LHC is for have a look at CERN's FAQ or wikipedia .
The data analysis for the LHC experiments uses the LHC Computing Grid . The analysis is spread out between different sites (exactly what happens at which sites depends on the experiment). The PCs which make up the grid though are largely (fom what I have seen) Dell PCs.
Data analysis for particle physics is highly parallelisable (large number of events, on which you want to run the same analysis) so large numbers of inexpensive computers makes more sense than super computers.
Sounds like I won't be voting for him then.
Not that I was planning on voting anyway.
I am no expert on stats but I think you are confusing standard deviations. The SD of the IQ of the population of the world is (as you say) supposed to be 15 (by design). The standard deviation you need to calculate the standard error of their measurement is the standard deviation of the distribution of results of a measurement of a particular person's IQ (ie the square root of the mean square difference between their true IQ and the result of the test).
To work this out, you could:
You could assume that this distribution is the same for everyone and then divide this standard deviation by the square root of the number of people in each group to get a standard error for each group.
I am sure this method has problems but it is only an example.
In practice, for a decent test, the standard deviation of the results for a person with a given IQ should be much less than 15 and so I think your conclusion still applies.
"Either he gets the sex or he offends the other partly so badly that he never hears from him again." I don't think there is any question about it. If someone demanded a night with your sister or cousin in exchange for fixing your car or decorating your house you would be pretty pissed. Especially if they did so "as brazenly and obnoxiously as possible".
Actually isotropy means that it looks the same in every direction (there is no favoured direction). Homogeneity means that it is the same everywhere (there is no favoured point). The universe is thought to be both isotropic and homogenous. I am not sure exactly what you mean about the absolute reference point/frame. The equivalence of all inertial reference frames in special relativity is referring to physical measurements/results being equivalent for all observers who are not accelerating. I am not sure how a point like the centre of the universe would mess this up. I would be interested to know if I am missing something though.
In the UK lots of parents didn't let doctors give it to their kids because of scare stories about link between it and autism (which has been shown to not exist). It is the low uptake of the vacine (which is not very effective and so needs near 100% uptake to prevent outbreaks) which is causing cases here. I think that the resurgence of mumps in the UK is a completely different issue to the growing numbers of cases of dieseses like rickets here and abroad. Mumps outbreaks here are simply a result of irresponsible scare mongering by the british tabloids.
Believe me getting a launch is not easy. Although I am not going to say it is harder than building a satellite, that is very hard too.
None of the satellites you have mentioned are designed completely by students. Express is not based on any designs made by professionals like CubeSats are.
Satellites this size are usually refered to as micro. Micro satellites have just become the norm.
3 of them are being carried on Express. Unfortunately CubeSats are not really designed by students like SSETI's satellites, their critical sub-systems are based heavily on a design done by professionals. They are not nearly as interesting.
Our orbit will pass through the Van Allen belts so this is about as much of a torture test as you can get.
I have been wondering about this point since I read the summary. This comment is seriously underrated.
apart from being a unit of the police
The above described business plan is covered by business practice patent #123987 held by me. Any attempt to use this idea to make money would infringe and would force me to sue you. Business is definitely booming!
Of course there is going to be lower prices where Microsoft is competing. If you have to compete with someone who breaks all the rules it is hard. One of the things you are going to have to do is lower prices.
Microsoft is a large company. If you are competing with them then you are facing a lot of competition (a significant proportion of the total marketing budget for the whole software industry is Microsoft's) so of course there is more pressure on you to lower prices.
"First, in a poll of adult computer users taken by USA Today, only 6 percent said that "reducing Microsoft's influence" was a "major issue" to them. Most consumers love Microsoft's products. " As much as 6% of computer users think reducing Microsoft's influence is important? In other words most people who have actually used a computer that is not running Microsoft software (windows) think Microsoft is a bad thing, so bad in fact that reducing their influence is a "major issue". Hardly anyone thinks reducing Esso's influence in the oil market is a major issue but there is a whole campaign to boycott them, people hate Esso. Sounds like people hate Microsoft's products to me.
Just because prices fall because a company exists it doesn't make it good. It is well known that companies with too much market power lower prices to squeeze out competition so they can raise prices later and stop innovating (predatory pricing). This is a problem where there are barriers to entry in a market. Computer software has some of the highest barriers to entry of any market. You have to spend almost all of your costs (development costs) before you make a cent and there are proprietary standards that mean it is very hard to compete with an established rival since everything uses there standard.
This guy actually doesn't believe in market failure. Of course he thinks anti-trust laws are bad.
Assuming that it is unbreakable is dangerous. Quantum Theory while a very good theory is not the end of the story. The quantum systems people study to understand what is happening when a photon is emitted and transmitted through a optical fibber are also a simplification of what really happens and although the assumptions made are good ones there may be some subtle effect present that is only apparent when you solve a much more detailed (currently unsolvable) problem that more closely models reality. There may turn out to be away to crack it. No one can say for sure.
You might joke about the officials sense of humour but a British citizen was charged and given a prison sentence for joking to a friend about carrying a bomb while waiting to have her bag scanned (presumable for bombs or weapons) and her person scanned (for weapons) in the US. If they weren't listening in on her private conversation they wouldn't have had to get worried. Anyway doesn't america believe in freedom of speech? Doesn't locking someone up for something they said (to a friend) sort of conflict with that?
If I want to travel to the US I have to give them biometric data to be allowed into the country. They are already making it difficult for people to travel there (I heard about one high energy physicist that was not allowed to visit Fermilab for 2 weeks because of immigration checks). Because of their policy towards visitors, I would not visit the US unless I absolutely had to (professional reasons).
Despite not being given the chance to vote in the US (not being a US citizen) they seem to have decided that they have the juristiction to make laws that I have to follow while in the UK. The UK government also seems to have decided that it is ok for them to extradite me based on my violation of US law without a British judge having to agree (whithout demanding the same be applied to US citizens with regard to UK law) by making the Extradition Act law.
Could they just have been offered significant sums of money to stop (on condition they don't tell anyone)
I agree. Funny would have been much better. The problem is Slashdot is full of zealots.