I can make exactly the same argument for physics, maths, chemistry etc. only in this case your prior knowledge is insufficient. Obviously you would expect to develop a far better understanding of the subject if you choose to study it at university but I completely disagree that it is impossible to teach students the basics of what they need to know at school because they lack experience of a hard life. If that were the case then surely third world countries would be leading the planet in study of the humanities?
I absolutely agree that there are some fundamentals that every university student should know (I'd include basic calculus in that as well). All I'm doing is saying where those fundamentals should be learnt. If your society wants to do it by adding a 5th year on to university then that's your choice but it seems a really bad one. The alternative is to graduate engineers with less knowledge of engineering and since these are the people building your bridges, buildings, electronic devices etc. and you might not like the consequences of that either.
Yes, at school. This is where everyone should be exposed to a broad range of subjects to a reasonable level so they have an idea of which area (sciences, engineering, humanities etc.) they want to study at university. In the system I went through (before the UK government damaged it) everyone going to university had to do maths up to basic calculus, english language and literature plus a foreign language and a humanity up to the age of 16 (O' level) if they wanted to go to university.
If students are no longer leaving school with a broad enough and deep enough background as they should then fix the schools: don't dump the responsibility on the universities. Any broadening of programs at university comes at a cost of either lengthening the program or lowering the standards required to graduate in the particular field of study.
For example you construct a wormhole and transmit a message thru it from earth to mars.
Possibly correct (needs negative mass!) but it would not violate causality. It would be impossible for someone to stop the message being sent unless they were in the wormhole hence, even if in their frame the events happen in reverse order, it is not possible to violate causality from outside the wormhole.
You are making an assumption that such frames would need to exist. We don't really know if this is true at all.
Yes we do - basic first year relativity. If two events are causally connected i.e. event A causes event B then you can easily show that if the speed of information propagation between them exceeds 'c' you can construct a valid, inertial frame where the order of events is reversed. Go look at the relativity chapter in any first year university text book and there will be a section on proving this - at least it has been in all the text books I've used for teaching first year calculus based intro physics courses.
FTL wouldn't cause any problems with causality at all but a lot of other theories would have to go.
Correct - the theory you are wanting to get rid of is Special Relativity. This is the most precisely tested scientific theory there has ever been and not only is there no indication whatsoever of it being wrong but it is known that tunnelling does not carry information faster than light.
What you said violates the principle you stated, i.e. no information can travel faster than the speed of light. But a shadow could be used like a signalling device...
Indeed a shadow could be used as a signalling device but only from the object creating the shadow to the surface on which the shadow lies NOT between two points on the surface where the shadow lies. Same with the torch/laser: it communicates information from the earth to the moon NOT between two points on the moon (unless they signal the earth and then the earth signals back to the moon which, of course, will not be faster than light).
What is unclear though is whether tunneling can carry information. There is some indication that it can...
No that is clear - it cannot. If it could, and if there was any indication that it could, it would be direct evidence of the violation of causality. This is a "Big Thing" at ANY scale because all I have to do is find an intertial frame where the receipt of the information precedes its reception and then stop the information being transmitted. Having this restricted to a distance of a few cm just makes the resulting paradox less entertaining, but just as implausible, as the ones you see on Star Trek.
Can't the slashdot editors be more active with their copy? Nothing goes faster than light. period.
Correction: no information travels faster than light. It is easy to imagine a system which looks like something is moving faster than light: shine a bright enough torch on the moon. If you move the torch fast enough it will look like the spot on the Moon is moving faster than light. This is perfectly fine because there is no way to change the where the beam moves if you happen to be where the beam is pointing at a particular time i.e. no information flows between one spot and the next because everything is under the control of the torch wielder back on earth.
In QM tunnelling the transmission speed of information is always below the speed fo light and so there is no problem (if you know secondary [high] school physics this is like the difference between phase velocity and group velocity of a wave in a wave guide). However where the editors messed up is the statement:
...in circuits that warp even the most basic rules of physics.
These circuit DO NOT warp the basic rules of physics. Quantum mechanics IS a "basic rule of physics" - it is certainly counterintuitive but it is a fundamental rule of physics.
That's ok until the lawyers get involved and suddenly I get classified as a "slave to a foreign government".;-)
While I doubt that would really happen the problem is that if the politicians don't see a problem with treating foreigners differently in matters of justice law enforcement is going to start behaving that way. You might be able to get a judge to eventually rule that they are wrong but by this point you have been dragged through courts and had to fight the US government for those rights at a huge cost in time and money. You might expect to have to do that in some countries but not one whose government claims to champion human rights around the world surely?
I'm as fed up with all this PC crap as anyone but the solution is NOT to throw out our basic concepts of fairness and justice and target everyone who has a particular religious belief. That way you become no better than the fundamentalist terrorists themselves.
What we need to be doing is stamping down hard on the fundamentalists who preach violence and not shy away from this because of "religious freedom". If we had governments with the strength to target the fundamentalists that cause the problem and not give up when the going gets tough we could start to sort this problem out without the need to resort to indiscriminate attacks on a whole religion that will inflame the situation further.
Preferably, those liberties should extend to immigrants as well as natives.
The US is the only place I have ever been where that is apparently not the case. I was quite shocked to hear politicians and government officials on the news at one point explaining that the protections of the US constitution did not apply for foreigners in the US. While it is understandable that things like voting and extended habitation rights do depend on citizenship laws concerning the rights of someone accused of a crime, or freedom of speech have to be the same for everyone - it's fundamental to justice. They are called human, not US citizen, rights for a reason.
Only if you consider American citizens enemies of the American government.
Well, if you look back at history all US governments have fallen because of American citizens. Is it any wonder they are worried about you? Votes are lethal weapons to a democratic government and they need to know that yours are pointing in the right direction.
Actually the old idea of the aether was far more similar to the Higgs field than Dark matter or energy: it exists with a non-zero value everywhere in the universe and can be made to vibrate. However a vibration of the Higgs field is the Higgs boson, not a photon.
What he is advocating is not justice, indiscriminate or otherwise. There are many peace loving islamic people and tarring them with the same brush as the extremists is just ignorant. If you are not convinced then think about another collective group: your country. Would you want to be held accountable for the actions of your government? Assuming you are in a democracy, you have far more control their actions that than a muslim has over the actions of other muslims.
his appointment to the House of Lords is a strong argument in favour of getting rid of the undemocratic House of Lords, or at least making it an elected body.
Really? You think the people we elect to the house of commons are any better?
Being able to see gravity exists is a ways away from seeing that gravity is described by GR, which is what the conflict comes down to.
Eh? I don't know what you were discussing but I was discussing that the SM cannot explain gravity not whether General Relativity accurately describes gravity. Since the SM cannot explain gravity it cannot explain why an object will fall when dropped. Could you bolt some monstrosity onto the SM to explain that one situation? Possibly but I doubt it and, even if you did, what you added would not be gravity.
That is like arguing that special relativity does not preclude faster than light travel. You cannot add FTL travel to SR without inconsistencies (like breaking causality) but you technically can add it. You could also imagine developing a framework which expanded on SR and allowed FTL velocities. In the same way adding gravity to the Standard Model creates inconsistencies (renormalization cut-off) but you can imagine a framework which expands on the SM and somehow incorporates gravity.
The only difference between these two is that gravity is a phenomenon that clearly exists whereas FTL does not (as far as we know). Hence we say the SR forbids FTL because we have no way to incorporate FTL and we do not see it. In the same way the SM forbids gravity: it leads to inconsistencies in the theory just like FTL does in SR. However since gravity clearly exists we conclude that the SM is wrong not that gravity is forbidden!
I don't think anyone likes the Standard Model, it's inelegant and has more "elementary" particles than can be easily memorized, but it keeps making accurate predictions.
Actually that is not really true: just about anyone can do a very simple experiment which is inconsistent with the predictions of the Standard Model. Pick up an object and then let it go. There is nothing in the Standard Model which will predict the behaviour you observe. That's why we physicists don't like it. Parts of it are extremely elegant - e.g. the Higgs mechanism - but since it can't explain gravity we know it is wrong and yet we still cannot find any better model that works for all the other fundamental forces and gravity...not to mention explaining other phenomena like Dark Matter, matter/anti-matter asymmetry of the universe, baryon number violation... etc. The number of particles and free parameters is a minor issue!
Already been theorised and some experiments claimed to see them a while ago until they fixed their analysis. I'd personally hold out a bit longer before believing in tetraquarks - this is by no means the first claim to observe them and QCD spectroscopy is notoriously hard from both an experimental and theoretical point of view.
Before broadband there was a thing known as a modem which hooked up to a telephone line. I realise that you may not have heard of these existing, as they did, in that uninteresting bit of history between the late Cretaceous and yesterday. However posting on Slashdot is entirely possible through such a device. Some are still rumoured to exist out in the wilds, far beyond the sight of the last suburb, where the 3G reception icon on your phone starts to flicker.
They are generally accepted as less sapient (inteligent, wise, capable of abstract thought) than us, but the difference is not as wide as you might think - roughly comparable to a 4 to 5-year old human child IIRC.
4 and 5 years old kids can talk, read, write and paint recognizable objects. Chimps cannot. They may be smart but they are not at the same level as even a 4-5 year old child.
How else do you have academic freedom unless you have ownership control of the work you produce?
Excellent point - I had not thought of it quite that way before. However my moral rights (which exist in most countries and certainly in Canada) would protect me from alterations. Also they could not use this to stifle free speech, only to attempt to profit from it. This would kill a lot of motivation to produce such work - in many cases not because we want to profit from it ourselves (academia is the wrong field if that is your goal!) but because we want to be free to share it with whomever is interested.
Academics don't need copyright. They need to be free of it.
There I would disagree slightly - we need copyright like the GPL needs copyright: I want copyright as a way to ensure that whatever I produce and release will remain free.
Sorry but, at least at the institute I work at in Canada, faculty do own the intellectual property rights to material we create - including course material. There has been a push to formally codify those rights more clearly in the era of increasing IP silliness though both to protect the university and the faculty.
So why do you let the academic unions make these sorts of statements (effectively) on your behalf?
I don't have a choice - in fact in Alberta the Post-secondary Learning Act (PSLA) requires that I be a member of our faculty association (they are not technically a union) as a matter of law. However the real reason they get away with a lot of this rubbish is that most of us are too busy with other far more interesting and exciting things like research and teaching to have the time to refute every idiotic notion they espouse. The sad thing is that the few times they actually are doing something useful they typically get ignored because their signal to noise ratio is so poor.
I would be getting something out of it: the pleasure of reaching out and teaching so many people that the university is making $1M/year; my salary and lastly recognition. Not to mention that I'm sure I would be able to get some fraction of that revenue diverted to my department and faculty.
As for being fired this assumes that your university admin would want to fire someone who can write $1M/year courses; that they have someone capable of taking over in administering the course and that they can get around tenure somehow (the normal performance route would be REALLY hard to prove if you'd written a course like that!). However if I found myself in that incredibly unlikely situation I'd would obviously feel really ticked off and would then apply for a job at another university and point them to the $1M/year course I wrote for my previous employer as evidence of why they should hire me. If I were actually capable of writing a course that good I'd probably end up with a better position that the one I had!
Slashdot Mirror
I can make exactly the same argument for physics, maths, chemistry etc. only in this case your prior knowledge is insufficient. Obviously you would expect to develop a far better understanding of the subject if you choose to study it at university but I completely disagree that it is impossible to teach students the basics of what they need to know at school because they lack experience of a hard life. If that were the case then surely third world countries would be leading the planet in study of the humanities?
I absolutely agree that there are some fundamentals that every university student should know (I'd include basic calculus in that as well). All I'm doing is saying where those fundamentals should be learnt. If your society wants to do it by adding a 5th year on to university then that's your choice but it seems a really bad one. The alternative is to graduate engineers with less knowledge of engineering and since these are the people building your bridges, buildings, electronic devices etc. and you might not like the consequences of that either.
Did you ever take a humanities class?
Yes, at school. This is where everyone should be exposed to a broad range of subjects to a reasonable level so they have an idea of which area (sciences, engineering, humanities etc.) they want to study at university. In the system I went through (before the UK government damaged it) everyone going to university had to do maths up to basic calculus, english language and literature plus a foreign language and a humanity up to the age of 16 (O' level) if they wanted to go to university.
If students are no longer leaving school with a broad enough and deep enough background as they should then fix the schools: don't dump the responsibility on the universities. Any broadening of programs at university comes at a cost of either lengthening the program or lowering the standards required to graduate in the particular field of study.
For example you construct a wormhole and transmit a message thru it from earth to mars.
Possibly correct (needs negative mass!) but it would not violate causality. It would be impossible for someone to stop the message being sent unless they were in the wormhole hence, even if in their frame the events happen in reverse order, it is not possible to violate causality from outside the wormhole.
You are making an assumption that such frames would need to exist. We don't really know if this is true at all.
Yes we do - basic first year relativity. If two events are causally connected i.e. event A causes event B then you can easily show that if the speed of information propagation between them exceeds 'c' you can construct a valid, inertial frame where the order of events is reversed. Go look at the relativity chapter in any first year university text book and there will be a section on proving this - at least it has been in all the text books I've used for teaching first year calculus based intro physics courses.
FTL wouldn't cause any problems with causality at all but a lot of other theories would have to go.
Correct - the theory you are wanting to get rid of is Special Relativity. This is the most precisely tested scientific theory there has ever been and not only is there no indication whatsoever of it being wrong but it is known that tunnelling does not carry information faster than light.
What you said violates the principle you stated, i.e. no information can travel faster than the speed of light. But a shadow could be used like a signalling device...
Indeed a shadow could be used as a signalling device but only from the object creating the shadow to the surface on which the shadow lies NOT between two points on the surface where the shadow lies. Same with the torch/laser: it communicates information from the earth to the moon NOT between two points on the moon (unless they signal the earth and then the earth signals back to the moon which, of course, will not be faster than light).
What is unclear though is whether tunneling can carry information. There is some indication that it can...
No that is clear - it cannot. If it could, and if there was any indication that it could, it would be direct evidence of the violation of causality. This is a "Big Thing" at ANY scale because all I have to do is find an intertial frame where the receipt of the information precedes its reception and then stop the information being transmitted. Having this restricted to a distance of a few cm just makes the resulting paradox less entertaining, but just as implausible, as the ones you see on Star Trek.
Can't the slashdot editors be more active with their copy? Nothing goes faster than light. period.
Correction: no information travels faster than light. It is easy to imagine a system which looks like something is moving faster than light: shine a bright enough torch on the moon. If you move the torch fast enough it will look like the spot on the Moon is moving faster than light. This is perfectly fine because there is no way to change the where the beam moves if you happen to be where the beam is pointing at a particular time i.e. no information flows between one spot and the next because everything is under the control of the torch wielder back on earth.
In QM tunnelling the transmission speed of information is always below the speed fo light and so there is no problem (if you know secondary [high] school physics this is like the difference between phase velocity and group velocity of a wave in a wave guide). However where the editors messed up is the statement:
...in circuits that warp even the most basic rules of physics.
These circuit DO NOT warp the basic rules of physics. Quantum mechanics IS a "basic rule of physics" - it is certainly counterintuitive but it is a fundamental rule of physics.
That's ok until the lawyers get involved and suddenly I get classified as a "slave to a foreign government". ;-)
While I doubt that would really happen the problem is that if the politicians don't see a problem with treating foreigners differently in matters of justice law enforcement is going to start behaving that way. You might be able to get a judge to eventually rule that they are wrong but by this point you have been dragged through courts and had to fight the US government for those rights at a huge cost in time and money. You might expect to have to do that in some countries but not one whose government claims to champion human rights around the world surely?
I'm as fed up with all this PC crap as anyone but the solution is NOT to throw out our basic concepts of fairness and justice and target everyone who has a particular religious belief. That way you become no better than the fundamentalist terrorists themselves.
What we need to be doing is stamping down hard on the fundamentalists who preach violence and not shy away from this because of "religious freedom". If we had governments with the strength to target the fundamentalists that cause the problem and not give up when the going gets tough we could start to sort this problem out without the need to resort to indiscriminate attacks on a whole religion that will inflame the situation further.
Preferably, those liberties should extend to immigrants as well as natives.
The US is the only place I have ever been where that is apparently not the case. I was quite shocked to hear politicians and government officials on the news at one point explaining that the protections of the US constitution did not apply for foreigners in the US. While it is understandable that things like voting and extended habitation rights do depend on citizenship laws concerning the rights of someone accused of a crime, or freedom of speech have to be the same for everyone - it's fundamental to justice. They are called human, not US citizen, rights for a reason.
Only if you consider American citizens enemies of the American government.
Well, if you look back at history all US governments have fallen because of American citizens. Is it any wonder they are worried about you? Votes are lethal weapons to a democratic government and they need to know that yours are pointing in the right direction.
Actually the old idea of the aether was far more similar to the Higgs field than Dark matter or energy: it exists with a non-zero value everywhere in the universe and can be made to vibrate. However a vibration of the Higgs field is the Higgs boson, not a photon.
The indiscriminate justice you advocate...
What he is advocating is not justice, indiscriminate or otherwise. There are many peace loving islamic people and tarring them with the same brush as the extremists is just ignorant. If you are not convinced then think about another collective group: your country. Would you want to be held accountable for the actions of your government? Assuming you are in a democracy, you have far more control their actions that than a muslim has over the actions of other muslims.
his appointment to the House of Lords is a strong argument in favour of getting rid of the undemocratic House of Lords, or at least making it an elected body.
Really? You think the people we elect to the house of commons are any better?
Being able to see gravity exists is a ways away from seeing that gravity is described by GR, which is what the conflict comes down to.
Eh? I don't know what you were discussing but I was discussing that the SM cannot explain gravity not whether General Relativity accurately describes gravity. Since the SM cannot explain gravity it cannot explain why an object will fall when dropped. Could you bolt some monstrosity onto the SM to explain that one situation? Possibly but I doubt it and, even if you did, what you added would not be gravity.
The Standard Model doesn't preclude gravity
That is like arguing that special relativity does not preclude faster than light travel. You cannot add FTL travel to SR without inconsistencies (like breaking causality) but you technically can add it. You could also imagine developing a framework which expanded on SR and allowed FTL velocities. In the same way adding gravity to the Standard Model creates inconsistencies (renormalization cut-off) but you can imagine a framework which expands on the SM and somehow incorporates gravity.
The only difference between these two is that gravity is a phenomenon that clearly exists whereas FTL does not (as far as we know). Hence we say the SR forbids FTL because we have no way to incorporate FTL and we do not see it. In the same way the SM forbids gravity: it leads to inconsistencies in the theory just like FTL does in SR. However since gravity clearly exists we conclude that the SM is wrong not that gravity is forbidden!
I don't think anyone likes the Standard Model, it's inelegant and has more "elementary" particles than can be easily memorized, but it keeps making accurate predictions.
Actually that is not really true: just about anyone can do a very simple experiment which is inconsistent with the predictions of the Standard Model. Pick up an object and then let it go. There is nothing in the Standard Model which will predict the behaviour you observe. That's why we physicists don't like it. Parts of it are extremely elegant - e.g. the Higgs mechanism - but since it can't explain gravity we know it is wrong and yet we still cannot find any better model that works for all the other fundamental forces and gravity...not to mention explaining other phenomena like Dark Matter, matter/anti-matter asymmetry of the universe, baryon number violation... etc. The number of particles and free parameters is a minor issue!
Already been theorised and some experiments claimed to see them a while ago until they fixed their analysis. I'd personally hold out a bit longer before believing in tetraquarks - this is by no means the first claim to observe them and QCD spectroscopy is notoriously hard from both an experimental and theoretical point of view.
Before broadband there was a thing known as a modem which hooked up to a telephone line. I realise that you may not have heard of these existing, as they did, in that uninteresting bit of history between the late Cretaceous and yesterday. However posting on Slashdot is entirely possible through such a device. Some are still rumoured to exist out in the wilds, far beyond the sight of the last suburb, where the 3G reception icon on your phone starts to flicker.
They are generally accepted as less sapient (inteligent, wise, capable of abstract thought) than us, but the difference is not as wide as you might think - roughly comparable to a 4 to 5-year old human child IIRC.
4 and 5 years old kids can talk, read, write and paint recognizable objects. Chimps cannot. They may be smart but they are not at the same level as even a 4-5 year old child.
How else do you have academic freedom unless you have ownership control of the work you produce?
Excellent point - I had not thought of it quite that way before. However my moral rights (which exist in most countries and certainly in Canada) would protect me from alterations. Also they could not use this to stifle free speech, only to attempt to profit from it. This would kill a lot of motivation to produce such work - in many cases not because we want to profit from it ourselves (academia is the wrong field if that is your goal!) but because we want to be free to share it with whomever is interested.
Academics don't need copyright. They need to be free of it.
There I would disagree slightly - we need copyright like the GPL needs copyright: I want copyright as a way to ensure that whatever I produce and release will remain free.
Sorry but, at least at the institute I work at in Canada, faculty do own the intellectual property rights to material we create - including course material. There has been a push to formally codify those rights more clearly in the era of increasing IP silliness though both to protect the university and the faculty.
So why do you let the academic unions make these sorts of statements (effectively) on your behalf?
I don't have a choice - in fact in Alberta the Post-secondary Learning Act (PSLA) requires that I be a member of our faculty association (they are not technically a union) as a matter of law. However the real reason they get away with a lot of this rubbish is that most of us are too busy with other far more interesting and exciting things like research and teaching to have the time to refute every idiotic notion they espouse. The sad thing is that the few times they actually are doing something useful they typically get ignored because their signal to noise ratio is so poor.
I would be getting something out of it: the pleasure of reaching out and teaching so many people that the university is making $1M/year; my salary and lastly recognition. Not to mention that I'm sure I would be able to get some fraction of that revenue diverted to my department and faculty.
As for being fired this assumes that your university admin would want to fire someone who can write $1M/year courses; that they have someone capable of taking over in administering the course and that they can get around tenure somehow (the normal performance route would be REALLY hard to prove if you'd written a course like that!). However if I found myself in that incredibly unlikely situation I'd would obviously feel really ticked off and would then apply for a job at another university and point them to the $1M/year course I wrote for my previous employer as evidence of why they should hire me. If I were actually capable of writing a course that good I'd probably end up with a better position that the one I had!