Actually what the states refer to is something called helicity, not spin. However the two are closely related: helicity is the component of the spin in the particle's direction of motion. Since this is quantized electrons and quarks have only two possible states: either the spin is in the same direction as the direction of motion (right-handed) or it is opposite (left-handed).
The names come from the curl of your fingers in your left and right hands. If you pretend that the electron is a physically spinning object then for a right-handed particle if you curl your fingers in the direction of rotation your thumb points in the direction of motion. For a left handed particle you need to used your left hand.
I don't know how it is in the UK, but as a STEM graduate (and a software engineer), I can't really understand what you're implying about science and engineering not already being well paid jobs.
Take a look outside the UK. I'm a physicist, not an engineer, so with engineering or in industry it might be different. However as a scientist and an academic I had a look at UK based academic jobs after my postdoc and the picture was bleak to say the least. Apart from not being able to afford any sort of decent house (and this was up north just over a decade ago before the bubble) my sister who is 5 years my junior and has no advanced degrees would have been earning practically the same amount as a primary school teacher as I would have as a junior faculty member plus it would have been a slight step down from my US RA salary!
Now compare that to the offer I had from Canada where the salary was about 75% higher (and on a rapidly rising scale), the job had the possibility of tenure (no 5 year renewable contract) and the cost of a house was less than half what it was in the UK. Since I had a wife and kids to support guess which job I took? If the salary situation for scientists is so poor that even a british academic who is not really motivated by money beyond enough for a comfortable life and would have likes to have stayed in the UK is highly motivated to leave what on earth is the point of providing scholarships? It's already cheaper to go to university in Canada from the UK than it is to go to a UK university so why not save the UK some money and let british students come over here earlier because, unless the UK fixes the salary issue, the sad truth is that many of those with families who are willing to look abroad will be leaving in order to be able to support those families - either that or giving up science for management.
Perhaps a better solution would be for companies to stop paying all the money to the managers and pay more of it to the people who actually make the company work. That way more people will want to get science and engineering because they lead to a valued and well paid job. Why would someone motivated by money take a few thousand pounds from the government now when they can get hundreds of thousands of pounds more over their career doing a far less challenging degree and setting themselves up to become a manager?
All waves — whether visible light, sound, radio or otherwise — have a physical property known as time reversal symmetry — a wave sent one way can always be sent back.
No, not all waves. Kaon and B-meson waves violate time reversal symmetry. We have known about this for almost 20 years since the first CPLEAR paper on the evidence of this and the more recent papers from Babar have confirmed it beyond any reasonable doubt. I'm always amazed how such a fundamental result as the laws of physics defining a direction of time (even when you take account of phase space/entropy effects) seems to be forgotten by many physicists.
Nuance is out, and so seem to be reassessment and compromise.
I'd certainly agree that is my impression of a lot of issues in the US - you seem to have two extremes with no middle ground and while I no longer live there it does seem from the outside that the problem is getting worse and not better. It exists elsewhere too but nowhere near to the same extent as the US. However with Snowden I think you have an issue that is very likely to force people to one side or the other.
Snowden broke extremely serious laws and severely embarrassed the US government and damaged US reputation worldwide. He comes across as an intelligent person knowing full well exactly what he was doing and why so there is no possibility to claim that it was somehow inadvertent or he could not foresee the consequences. So either you have to really choose between whether or not he was justified in breaking the law and that pretty much forces you into one camp or the other....but that does not have to mean that your opinion is a "fixed belief" it just means there are few tenable middle positions for this topic.
Too much news, too fast, the TV presenting them with headstrong showmen instead of analytical journalists
You can also add to this the fact that with so many media sources to choose from you can select only the news and opinions that you want to hear so your opinion is never, or rarely challenged.
The excuse "but I was just following orders" has already been tried.
True, but it typically only fails as an excuse when the people who gave the orders have been removed from power. The problem with illegal orders is that while those giving them are in power not following them is illegal but once they are out of power having followed them is illegal. It's a no-win situation for those involved.
Understanding the 19th century telegraph system helps understand our current global internet.
That might be true but learning about our current global internet directly is a more efficient way to understand it. If you don't already understand modern internet technology then surely it is a higher priority to learn about this directly rather than teach them the full history of how it was developed? We don't teach physics students the details of epicycles before covering Newtonian gravity nor do we teach students latin (any more) before learning modern languages like French. If my kids are interested in those topics then I'd certainly help them learn them but in terms of encouraging them to learn it I'd leave that up to their own personal interest - it's not something I think they need to know.
Denying the Holocaust is illegal here in Germany not because of opinion but because it is a false statement, clearly and irrefutably documented.
Do you arrest people who deny evolution or climate change? These are clearly and irrefutably documented facts. The reason that denying the holocaust is illegal is entirely because of public opinion - or rather public fear as to what it might lead to. It happens to be a false statement too but that is justification after the fact otherwise why single out just the one false statement from all the other false things idiots say?
The danger with laws like this is that they try to force individuals into thinking or believing a particular thing. No matter how well intentioned it is this simply does not work. The only way to fight ignorance, even willful ignorance, is with education not laws. Think of it like a vaccination: education does not seem to take hold in everyone exposed to it but so long as it reaches enough of the population there is sufficient immunity that stupidity and ignorance can't become dangerous and spread.
yup, they're economists basing everything around economics.
True, but the proposal is not just economics but economics with a political bias thrown in. For example you could allow selling of human organs to encourage supply while requiring that they are sold to a central agency that then distributes them to hospitals based on where they will be most effective. This would be using economics to encourage supply while still maximizing the life saving potential of those organs by directing them based on medical need and prognosis rather than bank balance. It would probably also work well in the majority of countries which have a national health care system.
While I'm still not sure I really agree with even this it would be one way to use economics to address the stated problem of a lack of supply. Of course it would not let rich people use their money to get preferential access to organs but surely this was an unimportant, unintended side-effect of the original proposal, right?
... the world out there will NOT believe in you when they know you are from Russia
Really? All of my Russian colleagues in physics are incredibly talented and well trained and have great senses of humor too! Based on this experience I'd have zero hesitation in accepting a suitably skilled Russian grad student and I hope this programme causes more of them to apply to my institute. If they have to go back to work in Russia afterwards then that's not a bad thing - science it a global enterprise and it will undoubtedly help Russia build ties with the global community is is good for everyone.
Yellowstone super volcano is a planetary killer - or best scenario: many, many, many years of the equivalent of nuclear winter.
With "many, many, many years" meaning about 10 if you read the article (yes, I know it's slashdot...). However if you are worried about the more immediate effect then I'd rather be west than east of the super volcano given that the prevailing winds are westerlies and will distribute the ~1,000 cubic kilometres of ash mainly to the east of the eruption.
However there is some hope for the long term. With global warming predicted to hit +4C by around 2100 having a super volcanic eruption may actually be a good thing in a century or two.
Firstly a sign of a good educator is if he can explain concepts so a 9 year old will understand it.
No, that is a sign of a good educator who is actually teaching nine year olds. I can teach quantum mechanics at a level that a nine year old can understand it but I absolutely do not do that when I'm lecturing in university because it would require that I leave out all of the detailed concepts and maths that those taking a physics degree need to know.
Secondly from personal experience up to 1/2 of a first year University course is very basic since they assume no knowledge.
You went to a bad university. Everywhere I've been as a student, postdoc or a faculty member has intro courses which rely heavily on secondary school level material. It's true that the level starts a bit below the end of secondary school to give students from different backgrounds time to catch up but it's still well above primary school level.
I suspect a large number of the "failures" are just people who had good intentions to follow a course but didn't devote the time to it after all.
Really? I suspect that the majority are people just curious to find out what an online course is like and so sign up to find out and then, when it fails to meet expectations, drop out.
As for the level of education offered I suspect it varies hugely. My 9 year old son signed up for a Udacity python course and managed to complete 50% of it so I suspect that the level of education from that course was around the primary school level - quite a bit below the university level it is supposed to be at.
...while saying things like, "I find your lack of faith disturbing."
That's your generic Dark Lord, your internet Dark Lord would say "I find your lack of windows disturbing." or "I am altering the website's terms of service. Pray I don't alter them any further.".
They think a "slouchy scholar" is cooler? So what?
Well it makes sense that the non-conformist is better at their job. If they can still hold a job while violating the norms of the position then it probably means there is some other reason why s/he still has a job. Ironically though this is not necessarily true for university professors because we have tenure and, so long as we satisfy public decency laws, we can dress how we like and provided our teaching and research is up to standard there is not much that anyone can do about it.
It's interesting actually... I genuinely wondered why you don't get mildly electrocuted when you touch the completely exposed connectors end of it
For the same reason that you don't get "mildly electrocuted" from the exposed terminals of a battery or when kids play with Scalextrix or model trains both of which have lots of exposed metal with an electrical potential between them. Your body's electrical resistance is large enough that a small DC voltage is not enough to drive a current large enough that you would notice it.
The disabling of the power unless it it plugged in is more probably to prevent the magnets making the plug stick onto a metal surface and short out the supply which would likely blow some internal fuse that would not be trivial to replace.
There is certainly no arguing that strictly enforced gun control is the immediate way to stop this problem. However this is really just like giving aspirin to lower a fever: it's addressing the symptoms not the underlying cause. While it may bring the US some immediate relief from these horrendous crimes in the long term it is not a solution and if the underlying cause is not addressed my guess is that given time someone will start to commit the same sort of crimes using weapons constructed from things which are a lot harder to control e.g. explosives, poison gas etc. made from commonly available and useful chemicals.
Well for a real frozen time effect you need the LHC - time passes over 14,000 times slower for the protons in it than it does for us. Although it is a little bit less interesting on film given that the protons don;t really do much!
While I agree that the device is really interesting comparing it to the LHC is like comparing a pea shooter to a nuclear missile. Our "cameras" are 14 storeys tall, take 25 million pictures per second, have single cables that are over 500m long and took decades of work by thousands of people to design and build. The feeling you get when something that big finally works and, even better, discovers some new, fundamental physics is a little bit more intense.
You're missing the point -- the vacuum itself has no temperature; that was the statement.
A temperature is just a measure of energy. In material this is the energy of the vibrations of the atoms and molecules. In a vacuum it is the vibration of the EM field. Put a 'cold' material in a 'hot' vacuum and it's atoms will start to vibrate with a particular energy associated with the EM energy in that vacuum. Put a 'hot' object into a 'cold' vacuum and it will radiate EM energy and heat up the vacuum.
The energy may be stored in slightly different ways but it's really not any more different than the fact that water stores in energy in H20 molecular vibrations and nitrogen storing it in N2 molecular vibrations. We don't have separate concepts of temperature for these two materials so neither should we have a different concept for vacuum what stores its energy in EM field vibrations: they all couple and will exchange their heat energy.
True but a vacuum can still have a temperature - even an idealized perfect one. All a temperature is is a measure of energy - in a solid this energy is stored in vibrations of the atoms and molecules in a vacuum it is stored as vibrations of the EM field.
I've met plenty of engineers from cultures where questioning and innovation are highly discouraged and they couldn't innovate their way out of a paper bag.
True and I believe that is why this discrepancy in knowledge has not had any real, noticeable impact yet because at university you have to question if you are going to learn anything. However this is not a static picture - standards in the west are dropping and at some point all the innovation in the world is not going to help us because our kids won't have enough background to be able to ask interesting questions or, to use your analogy, they will find the inside of the paper bag so new and exciting because they have not seen one before that they won't know why anyone would want to innovate their way out of it.
Slashdot Mirror
Actually what the states refer to is something called helicity, not spin. However the two are closely related: helicity is the component of the spin in the particle's direction of motion. Since this is quantized electrons and quarks have only two possible states: either the spin is in the same direction as the direction of motion (right-handed) or it is opposite (left-handed).
The names come from the curl of your fingers in your left and right hands. If you pretend that the electron is a physically spinning object then for a right-handed particle if you curl your fingers in the direction of rotation your thumb points in the direction of motion. For a left handed particle you need to used your left hand.
I don't know how it is in the UK, but as a STEM graduate (and a software engineer), I can't really understand what you're implying about science and engineering not already being well paid jobs.
Take a look outside the UK. I'm a physicist, not an engineer, so with engineering or in industry it might be different. However as a scientist and an academic I had a look at UK based academic jobs after my postdoc and the picture was bleak to say the least. Apart from not being able to afford any sort of decent house (and this was up north just over a decade ago before the bubble) my sister who is 5 years my junior and has no advanced degrees would have been earning practically the same amount as a primary school teacher as I would have as a junior faculty member plus it would have been a slight step down from my US RA salary!
Now compare that to the offer I had from Canada where the salary was about 75% higher (and on a rapidly rising scale), the job had the possibility of tenure (no 5 year renewable contract) and the cost of a house was less than half what it was in the UK. Since I had a wife and kids to support guess which job I took? If the salary situation for scientists is so poor that even a british academic who is not really motivated by money beyond enough for a comfortable life and would have likes to have stayed in the UK is highly motivated to leave what on earth is the point of providing scholarships? It's already cheaper to go to university in Canada from the UK than it is to go to a UK university so why not save the UK some money and let british students come over here earlier because, unless the UK fixes the salary issue, the sad truth is that many of those with families who are willing to look abroad will be leaving in order to be able to support those families - either that or giving up science for management.
Perhaps a better solution would be for companies to stop paying all the money to the managers and pay more of it to the people who actually make the company work. That way more people will want to get science and engineering because they lead to a valued and well paid job. Why would someone motivated by money take a few thousand pounds from the government now when they can get hundreds of thousands of pounds more over their career doing a far less challenging degree and setting themselves up to become a manager?
All waves — whether visible light, sound, radio or otherwise — have a physical property known as time reversal symmetry — a wave sent one way can always be sent back.
No, not all waves. Kaon and B-meson waves violate time reversal symmetry. We have known about this for almost 20 years since the first CPLEAR paper on the evidence of this and the more recent papers from Babar have confirmed it beyond any reasonable doubt. I'm always amazed how such a fundamental result as the laws of physics defining a direction of time (even when you take account of phase space/entropy effects) seems to be forgotten by many physicists.
Nuance is out, and so seem to be reassessment and compromise.
I'd certainly agree that is my impression of a lot of issues in the US - you seem to have two extremes with no middle ground and while I no longer live there it does seem from the outside that the problem is getting worse and not better. It exists elsewhere too but nowhere near to the same extent as the US. However with Snowden I think you have an issue that is very likely to force people to one side or the other.
Snowden broke extremely serious laws and severely embarrassed the US government and damaged US reputation worldwide. He comes across as an intelligent person knowing full well exactly what he was doing and why so there is no possibility to claim that it was somehow inadvertent or he could not foresee the consequences. So either you have to really choose between whether or not he was justified in breaking the law and that pretty much forces you into one camp or the other....but that does not have to mean that your opinion is a "fixed belief" it just means there are few tenable middle positions for this topic.
Too much news, too fast, the TV presenting them with headstrong showmen instead of analytical journalists
You can also add to this the fact that with so many media sources to choose from you can select only the news and opinions that you want to hear so your opinion is never, or rarely challenged.
The excuse "but I was just following orders" has already been tried.
True, but it typically only fails as an excuse when the people who gave the orders have been removed from power. The problem with illegal orders is that while those giving them are in power not following them is illegal but once they are out of power having followed them is illegal. It's a no-win situation for those involved.
Understanding the 19th century telegraph system helps understand our current global internet.
That might be true but learning about our current global internet directly is a more efficient way to understand it. If you don't already understand modern internet technology then surely it is a higher priority to learn about this directly rather than teach them the full history of how it was developed? We don't teach physics students the details of epicycles before covering Newtonian gravity nor do we teach students latin (any more) before learning modern languages like French. If my kids are interested in those topics then I'd certainly help them learn them but in terms of encouraging them to learn it I'd leave that up to their own personal interest - it's not something I think they need to know.
AFAIK, it's illegal in the US to use genetic information in choosing health insurance rates.
That is clearly not true since they already differentiate as to whether or not you have a Y chromosome.
Denying the Holocaust is illegal here in Germany not because of opinion but because it is a false statement, clearly and irrefutably documented.
Do you arrest people who deny evolution or climate change? These are clearly and irrefutably documented facts. The reason that denying the holocaust is illegal is entirely because of public opinion - or rather public fear as to what it might lead to. It happens to be a false statement too but that is justification after the fact otherwise why single out just the one false statement from all the other false things idiots say?
The danger with laws like this is that they try to force individuals into thinking or believing a particular thing. No matter how well intentioned it is this simply does not work. The only way to fight ignorance, even willful ignorance, is with education not laws. Think of it like a vaccination: education does not seem to take hold in everyone exposed to it but so long as it reaches enough of the population there is sufficient immunity that stupidity and ignorance can't become dangerous and spread.
yup, they're economists basing everything around economics.
True, but the proposal is not just economics but economics with a political bias thrown in. For example you could allow selling of human organs to encourage supply while requiring that they are sold to a central agency that then distributes them to hospitals based on where they will be most effective. This would be using economics to encourage supply while still maximizing the life saving potential of those organs by directing them based on medical need and prognosis rather than bank balance. It would probably also work well in the majority of countries which have a national health care system.
While I'm still not sure I really agree with even this it would be one way to use economics to address the stated problem of a lack of supply. Of course it would not let rich people use their money to get preferential access to organs but surely this was an unimportant, unintended side-effect of the original proposal, right?
The Daleks dropped that when they found that DR-DOS made them run a lot faster.
... the world out there will NOT believe in you when they know you are from Russia
Really? All of my Russian colleagues in physics are incredibly talented and well trained and have great senses of humor too! Based on this experience I'd have zero hesitation in accepting a suitably skilled Russian grad student and I hope this programme causes more of them to apply to my institute. If they have to go back to work in Russia afterwards then that's not a bad thing - science it a global enterprise and it will undoubtedly help Russia build ties with the global community is is good for everyone.
sometimes a publisher contracts/purchases a development studio that actually knows it's shit?
Well that would be the case for EA. I imagine most development studios "know it is shit" by now. You did mean to include that apostrophe right?
Yellowstone super volcano is a planetary killer - or best scenario: many, many, many years of the equivalent of nuclear winter.
With "many, many, many years" meaning about 10 if you read the article (yes, I know it's slashdot...). However if you are worried about the more immediate effect then I'd rather be west than east of the super volcano given that the prevailing winds are westerlies and will distribute the ~1,000 cubic kilometres of ash mainly to the east of the eruption.
However there is some hope for the long term. With global warming predicted to hit +4C by around 2100 having a super volcanic eruption may actually be a good thing in a century or two.
Firstly a sign of a good educator is if he can explain concepts so a 9 year old will understand it.
No, that is a sign of a good educator who is actually teaching nine year olds. I can teach quantum mechanics at a level that a nine year old can understand it but I absolutely do not do that when I'm lecturing in university because it would require that I leave out all of the detailed concepts and maths that those taking a physics degree need to know.
Secondly from personal experience up to 1/2 of a first year University course is very basic since they assume no knowledge.
You went to a bad university. Everywhere I've been as a student, postdoc or a faculty member has intro courses which rely heavily on secondary school level material. It's true that the level starts a bit below the end of secondary school to give students from different backgrounds time to catch up but it's still well above primary school level.
I suspect a large number of the "failures" are just people who had good intentions to follow a course but didn't devote the time to it after all.
Really? I suspect that the majority are people just curious to find out what an online course is like and so sign up to find out and then, when it fails to meet expectations, drop out.
As for the level of education offered I suspect it varies hugely. My 9 year old son signed up for a Udacity python course and managed to complete 50% of it so I suspect that the level of education from that course was around the primary school level - quite a bit below the university level it is supposed to be at.
Unlike religion it is possible to "worship" two or more OSes
Ah but at a fundamental level you can only have one endianess at a time and, unless you return to the source, it's hard to switch!
...while saying things like, "I find your lack of faith disturbing."
That's your generic Dark Lord, your internet Dark Lord would say "I find your lack of windows disturbing." or "I am altering the website's terms of service. Pray I don't alter them any further.".
They think a "slouchy scholar" is cooler? So what?
Well it makes sense that the non-conformist is better at their job. If they can still hold a job while violating the norms of the position then it probably means there is some other reason why s/he still has a job. Ironically though this is not necessarily true for university professors because we have tenure and, so long as we satisfy public decency laws, we can dress how we like and provided our teaching and research is up to standard there is not much that anyone can do about it.
It's interesting actually... I genuinely wondered why you don't get mildly electrocuted when you touch the completely exposed connectors end of it
For the same reason that you don't get "mildly electrocuted" from the exposed terminals of a battery or when kids play with Scalextrix or model trains both of which have lots of exposed metal with an electrical potential between them. Your body's electrical resistance is large enough that a small DC voltage is not enough to drive a current large enough that you would notice it.
The disabling of the power unless it it plugged in is more probably to prevent the magnets making the plug stick onto a metal surface and short out the supply which would likely blow some internal fuse that would not be trivial to replace.
There is certainly no arguing that strictly enforced gun control is the immediate way to stop this problem. However this is really just like giving aspirin to lower a fever: it's addressing the symptoms not the underlying cause. While it may bring the US some immediate relief from these horrendous crimes in the long term it is not a solution and if the underlying cause is not addressed my guess is that given time someone will start to commit the same sort of crimes using weapons constructed from things which are a lot harder to control e.g. explosives, poison gas etc. made from commonly available and useful chemicals.
Well for a real frozen time effect you need the LHC - time passes over 14,000 times slower for the protons in it than it does for us. Although it is a little bit less interesting on film given that the protons don;t really do much!
While I agree that the device is really interesting comparing it to the LHC is like comparing a pea shooter to a nuclear missile. Our "cameras" are 14 storeys tall, take 25 million pictures per second, have single cables that are over 500m long and took decades of work by thousands of people to design and build. The feeling you get when something that big finally works and, even better, discovers some new, fundamental physics is a little bit more intense.
You're missing the point -- the vacuum itself has no temperature; that was the statement.
A temperature is just a measure of energy. In material this is the energy of the vibrations of the atoms and molecules. In a vacuum it is the vibration of the EM field. Put a 'cold' material in a 'hot' vacuum and it's atoms will start to vibrate with a particular energy associated with the EM energy in that vacuum. Put a 'hot' object into a 'cold' vacuum and it will radiate EM energy and heat up the vacuum.
The energy may be stored in slightly different ways but it's really not any more different than the fact that water stores in energy in H20 molecular vibrations and nitrogen storing it in N2 molecular vibrations. We don't have separate concepts of temperature for these two materials so neither should we have a different concept for vacuum what stores its energy in EM field vibrations: they all couple and will exchange their heat energy.
True but a vacuum can still have a temperature - even an idealized perfect one. All a temperature is is a measure of energy - in a solid this energy is stored in vibrations of the atoms and molecules in a vacuum it is stored as vibrations of the EM field.
I've met plenty of engineers from cultures where questioning and innovation are highly discouraged and they couldn't innovate their way out of a paper bag.
True and I believe that is why this discrepancy in knowledge has not had any real, noticeable impact yet because at university you have to question if you are going to learn anything. However this is not a static picture - standards in the west are dropping and at some point all the innovation in the world is not going to help us because our kids won't have enough background to be able to ask interesting questions or, to use your analogy, they will find the inside of the paper bag so new and exciting because they have not seen one before that they won't know why anyone would want to innovate their way out of it.