True but currently there is no way to avoid that if I want to get from A to B rapidly so that's a (very tiny) risk I'm willing to take. What I am not willing to do is to double that risk unnecessarily when there are better technological options available including the pat down which carries zero risk. Why take even small risks with your health when there is no good reason to do so?
You have exactly two anecdotes about having no problem. How can you compare that to somebody who has flown with his equipment probably hundreds of times and only has a half-dozen anecdotes of problems?
Well there are also many of my physics colleagues who have, from time to time, flown with equipment and none of them has ever had trouble with security that I remember hearing about (although a few have had issues with customs forms). We do this quite a lot in particle physics so I think I can compare quite well with his anecdotes which are clearly very old since he mentions being invited to the cockpit which has not been possible since 2001 on a commercial plane. Besides if he has flown "hundreds of times" and only had an issue a tiny number of times why is he making such a fuss about it? His own statistics should tell him that this is a rare occurrence so there is no need to make a big deal about it.
Homeopathy has been shown not to work (read the third paragraph) so any theory which explains why it does work is clearly wrong because one of the predictions of such a theory (that homeopathy works) has been proven wrong.
No it cannot because it has no constraints on what is possible. String Theory does. For example if there is no SUSY then there is practically no possibility for Sting Theory. So if we ever get up to the Planck scale with future accelerators and still see no sign of SUSY then String Theory is probably toast. There is no equivalent possibility for creationism because the answer "god made it that way" can be used to answer anything.
So if I had a physical theory that needed the whole of the universe and 10^70 atoms to be testable it would be ok ?
No, because that would make it untestable in principle since the person running the test would be part of the test. Plus with the accelerating expansion of the Universe parts of the universe we can see today are now causally disconnected from us (or will be in the future) which completely prevents us from interacting with them to set up such a test.
And had the LHC not found the Higgs boson it wouldn't have destroyed the standard model.
Actually yes it would have because we had an upper limit set on the Higgs mass, about 1 TeV/c^2, above which the SM violated the unitarity bound without the Higgs i.e. the calculated probability of an event happening would have exceeded 100%. When that happens your model is broken. However you are right than just being testable was not the reason physicists love the Higgs mechanism: the reason we love it is because it is an extremely elegant solution to the problem of particle masses.
To be a useful, interesting scientific theory you need something which, with the right technology, is testable and which also explains a problem with current understanding. Without the former you have a story, not a scientific theory, and without the latter you might have a scientific theory but nobody will be interested in it and so want to test it.
String theory is arguably not science not because it makes predictions we cannot test, but because it basically makes no predictions at all.
It makes no predictions at all at low energy. However if by some miracle we figured out how to build a Planck-scale accelerator tomorrow and went to the String Theorists asking for predictions of what we would see I expect that we would immediately get predictions for phenomena which would start to rule out the possibilities. The String Theorists I've asked about predictions have all indicated that the problem is making predictions of low energy phenomena and not at high energy. This is not surprising given the huge difference in energy scale - in some ways it would probably be like trying to use the Standard Model of particle physics to explain low temperature superconductors. In theory this should work but in practice it would be hopelessly complex and almost impossible to use to come up with any sensible predictions for observable phenomena.
Problem is, supersymmetry (SUSY) is the only theory that even attempts to explain why the masses of particles are as small as they are -- including the Higgs particle. Without SUSY, the Higgs, W, and Z bosons become nearly infinitely massive due to loops in their feynmen diagrams.
Not quite. Only the Higgs is affected since it is the only scalar particle. Its mass does not become even vaguely close to infinite they just get dragged up to the Planck-scale at 10^19 GeV. SUSY is not the only possible explanation: Large Extra Dimensions solves the problem by reducing the Planck scale to ~10 TeV or so (but introduces other problems like why do protons appear stable).
Sparticles are a good candidate for dark matter, but they're unlikely to be detected by the LHC.
Only the lightest sparticle is good candidate for Dark Matter and, if produced, it can be detected at the LHC by the missing momentum which is carries which is a typical signature in almost all SUSY searches. However to confirm that it is Dark Matter we need the underground experiments to see it as well since all the LHC will be able to tell is that it lived long enough to escape the detector i.e. about 50ns if travelling close to the speed of light. However to be Dark Matter it needs to be stable enough to last ~13.8 billion years without appreciable decay.
If no sparticles are found at higher energy levels, then someone will have to explain what's wrong with particle physics in general
That depends. Suppose I tosh a coin and keep getting heads. How many heads in a row do I need to get before you become suspicious that something is not right (e.g. that I'm lying or tossing a two headed coin)? 10 heads in a row? 20 heads? Even if you are suspicious how many heads do I need to tosh before you are certain that something is wrong? This is the problem that the Standard Mode faces. It is not impossible that the light Higgs came about by really phenomenal luck but the chance of that happening is about the same as tossing ~110 heads in a row. In my subjective opinion that means that there must be some physics we are missing but this is a subjective opinion and you still cannot completely rule out that it could be just down to phenomenal chance.
The author claims that there is no test that can be done that would prove String Theory true as opposed to other theories.
Unfortunately the author has proven many times that he does not understand particle physics in previous posts. The problem with String Theory is that there are far too many possible theories to consider (last count I heard it was around 10^500) to make detailed, concrete predictions. The second that we get an experimental signature for something like String Theory that number would collapse and theorists would be able to start studying the detailed predictions of a vastly smaller number of models. This would undoubtedly lead to some clever theorist coming up with signatures unique to String Theory which other, competing models would not have.
If you can't come up with ANY difference it would mean that the theories must be mathematically equivalent for all situations which are possible. We have had this happen in physics before. Matrix mechanics and wave mechanics are both different ways of doing the same Quantum Mechanics. Nobody worries about which is the "right" way because both make mathematically equivalent predictions.
That is not my understanding. If we could build an accelerator that could reach the Planck scale then we could test quantum gravity and study the emission of gravitons, quantum decay of black holes etc. which I understood String Theory made predictions for. Certainly with the Large Extra Dimension theories which the LHC looks for the different theories can provide different signatures in particular circumstances for effects leading up to Black Hole formation.
The condition for science is that it has to be testable in principle, NOT that it has to be testable within the limits of current technology. When Higgs came up with his theory there was no accelerator capable of testing it (although we did not know that at the time). So would that make the Higgs mechanism non-science until the 21st century when we built the LHC? Clearly not. So, unless String theory is completely untestable in principle, regardless of potential future technological advances, it is science albeit science which is currently impossible to test with current technology.
Can it be scaled up enough to build cars, bridges and buildings out of it?
I think the real question is whether it should be used for these purposes. If you do decide to go ahead and get a car made of this alloy please get a dash cam with wireless streaming because you may end up with a spectacular youtube video, albeit is short sone since the camera probably won't take long to melt!
I completely agree...because I've done exactly what you suggest! I was flying to give a public outreach talk on physics and took some demos with me which included a microwave transmitter and receiver plus other electronics. At check-in I told the person behind the counter that my checked bag contained equipment which might look a bit strange since it was for physics demos for a talk I was giving. She told me that she didn't think it would be a problem but told me I could take it direct to a scanner they had in the check-in hall itself for checked bags. I took it there, explained again, the guy scanned it and said it looked fine and off it went on the conveyor belt.
I did the same on the flight back with the same result. No problems whatsoever and some curiosity as to what the demo was. I expect that if you explain that you have scientific equipment in your bag, why you have that equipment and that it might look a bit strange to the X-ray in advance you'll not have any problems. If you want to use actually a scientific device on the plane then the best thing to do is ask permission beforehand and not just state that you are going to use it to some random check-in person who probably has no technical background whatsoever. If this guy put even the tiniest amount of thought into getting his gear through security and getting permission to use it on a plane then I expect he would not have half the problems he claims to.
The problem with that argument is that you can make it almost anywhere because it is always safer not to risk making people angry. For example in the US any member of the public might be carrying a gun and if they saw something which made them angry they might shoot someone. So you'd better not allow any signs anywhere which might offend someone. Then of course they might overhear something so better ban that type of speech as well and pretty soon you can kiss all your freedoms goodbye.
Too bad we don't have s similar limit for copyright.
You do only instead of having to fight and defend the trademark to keep it protected with copyright companies have to fight the copyright law to keep on extending it so it remains protected.
You could project rings of glowing dots up a space about 3 feet from the hilt, creating a cylinder of glowing light in the air very similar to the appearance of a lightsaber, but harmless.
I would not describe the power of laser required to do this as "harmless".
I would agree but only if the scanner is of the safe sort which uses Terahertz radiation. While a pat down would not be pleasant I'd take it any day over the backscatter X-ray scanners which have a tiny, but non-zero, chance of giving you cancer. While this risk is tiny there is absolutely no need to take it given that there are perfectly safe scanners available. So if the TSA is going to be able to compel you to get scanned then they need to be compelled to provide safe scanners which use non-ionizing radiation.
This only applies to airlines and the airline did not deny the family boarding, the US government did. This is clearly stated in the second sentence of the page you linked:
This concerns delays, cancellations and overbooking that prevent you from boarding
They had applied for "authorization" in advance, which isn't the same as a visa.
Only in the semantics since a visa really is just authorization to travel to a country. I often wonder if anyone in the US government appreciates the irony of still referring to it as the "visa waiver program" since effectively you are applying for a visa (even if they refuse to call it that) to be part of the visa waiver program.
This is actually the problem with the fast breeder program is that it works by converting Uranium-238 into highly fissionable Plutonium-239. This means that you need lots of Plutonium reactors to burn the fuel but this poses a security risk because the Plutonium fuel is relatively easy to convert into a nuclear weapon unlike most uranium fuel which nowadays is not weapons grade and so cannot be used to build a nuclear device.
So while there may be some efficiencies with recycling the fuel the security concerns, especially in this day and age, perhaps out weigh any benefit.
After some of the damage we have done in the last 15 years, I don't know if that's still the case.
It's not and I was in the US and saw the change firsthand myself since it affected me. I was an RA with a US university and worked part of the time at Fermilab. When I started there in the late 1990's the senior European postdocs who were on the experiment I was on were all looking for faculty positions in the US. 4 years later, after the 11/9 attacks, almost every European postdoc, myself included, was looking to get out of the US at the earliest possible opportunity. I don't know any who were planning to stay.
Slashdot Mirror
True but currently there is no way to avoid that if I want to get from A to B rapidly so that's a (very tiny) risk I'm willing to take. What I am not willing to do is to double that risk unnecessarily when there are better technological options available including the pat down which carries zero risk. Why take even small risks with your health when there is no good reason to do so?
You have exactly two anecdotes about having no problem. How can you compare that to somebody who has flown with his equipment probably hundreds of times and only has a half-dozen anecdotes of problems?
Well there are also many of my physics colleagues who have, from time to time, flown with equipment and none of them has ever had trouble with security that I remember hearing about (although a few have had issues with customs forms). We do this quite a lot in particle physics so I think I can compare quite well with his anecdotes which are clearly very old since he mentions being invited to the cockpit which has not been possible since 2001 on a commercial plane. Besides if he has flown "hundreds of times" and only had an issue a tiny number of times why is he making such a fuss about it? His own statistics should tell him that this is a rare occurrence so there is no need to make a big deal about it.
What about homeopathy?
Homeopathy has been shown not to work (read the third paragraph) so any theory which explains why it does work is clearly wrong because one of the predictions of such a theory (that homeopathy works) has been proven wrong.
Creationism could make the same argument.
No it cannot because it has no constraints on what is possible. String Theory does. For example if there is no SUSY then there is practically no possibility for Sting Theory. So if we ever get up to the Planck scale with future accelerators and still see no sign of SUSY then String Theory is probably toast. There is no equivalent possibility for creationism because the answer "god made it that way" can be used to answer anything.
So if I had a physical theory that needed the whole of the universe and 10^70 atoms to be testable it would be ok ?
No, because that would make it untestable in principle since the person running the test would be part of the test. Plus with the accelerating expansion of the Universe parts of the universe we can see today are now causally disconnected from us (or will be in the future) which completely prevents us from interacting with them to set up such a test.
And had the LHC not found the Higgs boson it wouldn't have destroyed the standard model.
Actually yes it would have because we had an upper limit set on the Higgs mass, about 1 TeV/c^2, above which the SM violated the unitarity bound without the Higgs i.e. the calculated probability of an event happening would have exceeded 100%. When that happens your model is broken. However you are right than just being testable was not the reason physicists love the Higgs mechanism: the reason we love it is because it is an extremely elegant solution to the problem of particle masses.
To be a useful, interesting scientific theory you need something which, with the right technology, is testable and which also explains a problem with current understanding. Without the former you have a story, not a scientific theory, and without the latter you might have a scientific theory but nobody will be interested in it and so want to test it.
String theory is arguably not science not because it makes predictions we cannot test, but because it basically makes no predictions at all.
It makes no predictions at all at low energy. However if by some miracle we figured out how to build a Planck-scale accelerator tomorrow and went to the String Theorists asking for predictions of what we would see I expect that we would immediately get predictions for phenomena which would start to rule out the possibilities. The String Theorists I've asked about predictions have all indicated that the problem is making predictions of low energy phenomena and not at high energy. This is not surprising given the huge difference in energy scale - in some ways it would probably be like trying to use the Standard Model of particle physics to explain low temperature superconductors. In theory this should work but in practice it would be hopelessly complex and almost impossible to use to come up with any sensible predictions for observable phenomena.
Problem is, supersymmetry (SUSY) is the only theory that even attempts to explain why the masses of particles are as small as they are -- including the Higgs particle. Without SUSY, the Higgs, W, and Z bosons become nearly infinitely massive due to loops in their feynmen diagrams.
Not quite. Only the Higgs is affected since it is the only scalar particle. Its mass does not become even vaguely close to infinite they just get dragged up to the Planck-scale at 10^19 GeV. SUSY is not the only possible explanation: Large Extra Dimensions solves the problem by reducing the Planck scale to ~10 TeV or so (but introduces other problems like why do protons appear stable).
Sparticles are a good candidate for dark matter, but they're unlikely to be detected by the LHC.
Only the lightest sparticle is good candidate for Dark Matter and, if produced, it can be detected at the LHC by the missing momentum which is carries which is a typical signature in almost all SUSY searches. However to confirm that it is Dark Matter we need the underground experiments to see it as well since all the LHC will be able to tell is that it lived long enough to escape the detector i.e. about 50ns if travelling close to the speed of light. However to be Dark Matter it needs to be stable enough to last ~13.8 billion years without appreciable decay.
If no sparticles are found at higher energy levels, then someone will have to explain what's wrong with particle physics in general
That depends. Suppose I tosh a coin and keep getting heads. How many heads in a row do I need to get before you become suspicious that something is not right (e.g. that I'm lying or tossing a two headed coin)? 10 heads in a row? 20 heads? Even if you are suspicious how many heads do I need to tosh before you are certain that something is wrong? This is the problem that the Standard Mode faces. It is not impossible that the light Higgs came about by really phenomenal luck but the chance of that happening is about the same as tossing ~110 heads in a row. In my subjective opinion that means that there must be some physics we are missing but this is a subjective opinion and you still cannot completely rule out that it could be just down to phenomenal chance.
Build an accelerator that can reach the Planck scale which is about 10^15 times higher in energy than the LHC.
The author claims that there is no test that can be done that would prove String Theory true as opposed to other theories.
Unfortunately the author has proven many times that he does not understand particle physics in previous posts. The problem with String Theory is that there are far too many possible theories to consider (last count I heard it was around 10^500) to make detailed, concrete predictions. The second that we get an experimental signature for something like String Theory that number would collapse and theorists would be able to start studying the detailed predictions of a vastly smaller number of models. This would undoubtedly lead to some clever theorist coming up with signatures unique to String Theory which other, competing models would not have.
If you can't come up with ANY difference it would mean that the theories must be mathematically equivalent for all situations which are possible. We have had this happen in physics before. Matrix mechanics and wave mechanics are both different ways of doing the same Quantum Mechanics. Nobody worries about which is the "right" way because both make mathematically equivalent predictions.
It is.
That is not my understanding. If we could build an accelerator that could reach the Planck scale then we could test quantum gravity and study the emission of gravitons, quantum decay of black holes etc. which I understood String Theory made predictions for. Certainly with the Large Extra Dimension theories which the LHC looks for the different theories can provide different signatures in particular circumstances for effects leading up to Black Hole formation.
The condition for science is that it has to be testable in principle, NOT that it has to be testable within the limits of current technology. When Higgs came up with his theory there was no accelerator capable of testing it (although we did not know that at the time). So would that make the Higgs mechanism non-science until the 21st century when we built the LHC? Clearly not. So, unless String theory is completely untestable in principle, regardless of potential future technological advances, it is science albeit science which is currently impossible to test with current technology.
Can it be scaled up enough to build cars, bridges and buildings out of it?
I think the real question is whether it should be used for these purposes. If you do decide to go ahead and get a car made of this alloy please get a dash cam with wireless streaming because you may end up with a spectacular youtube video, albeit is short sone since the camera probably won't take long to melt!
I don't suppose who ever modded my post off-topic would care to explain the reasoning because I really don't see how this is the least bit off-topic.
I completely agree...because I've done exactly what you suggest! I was flying to give a public outreach talk on physics and took some demos with me which included a microwave transmitter and receiver plus other electronics. At check-in I told the person behind the counter that my checked bag contained equipment which might look a bit strange since it was for physics demos for a talk I was giving. She told me that she didn't think it would be a problem but told me I could take it direct to a scanner they had in the check-in hall itself for checked bags. I took it there, explained again, the guy scanned it and said it looked fine and off it went on the conveyor belt.
I did the same on the flight back with the same result. No problems whatsoever and some curiosity as to what the demo was. I expect that if you explain that you have scientific equipment in your bag, why you have that equipment and that it might look a bit strange to the X-ray in advance you'll not have any problems. If you want to use actually a scientific device on the plane then the best thing to do is ask permission beforehand and not just state that you are going to use it to some random check-in person who probably has no technical background whatsoever. If this guy put even the tiniest amount of thought into getting his gear through security and getting permission to use it on a plane then I expect he would not have half the problems he claims to.
But you could go for "The Untrademarkables".
The problem with that argument is that you can make it almost anywhere because it is always safer not to risk making people angry. For example in the US any member of the public might be carrying a gun and if they saw something which made them angry they might shoot someone. So you'd better not allow any signs anywhere which might offend someone. Then of course they might overhear something so better ban that type of speech as well and pretty soon you can kiss all your freedoms goodbye.
Too bad we don't have s similar limit for copyright.
You do only instead of having to fight and defend the trademark to keep it protected with copyright companies have to fight the copyright law to keep on extending it so it remains protected.
So does this mean that Microsoft should now count anyone who has looked through a window as a Windows user?
You could project rings of glowing dots up a space about 3 feet from the hilt, creating a cylinder of glowing light in the air very similar to the appearance of a lightsaber, but harmless.
I would not describe the power of laser required to do this as "harmless".
I would agree but only if the scanner is of the safe sort which uses Terahertz radiation. While a pat down would not be pleasant I'd take it any day over the backscatter X-ray scanners which have a tiny, but non-zero, chance of giving you cancer. While this risk is tiny there is absolutely no need to take it given that there are perfectly safe scanners available. So if the TSA is going to be able to compel you to get scanned then they need to be compelled to provide safe scanners which use non-ionizing radiation.
Well, there's Disneyland Paris, but...
This concerns delays, cancellations and overbooking that prevent you from boarding
None of these apply in this case.
They had applied for "authorization" in advance, which isn't the same as a visa.
Only in the semantics since a visa really is just authorization to travel to a country. I often wonder if anyone in the US government appreciates the irony of still referring to it as the "visa waiver program" since effectively you are applying for a visa (even if they refuse to call it that) to be part of the visa waiver program.
4. you have lots of weapon's grade plutonium.
This is actually the problem with the fast breeder program is that it works by converting Uranium-238 into highly fissionable Plutonium-239. This means that you need lots of Plutonium reactors to burn the fuel but this poses a security risk because the Plutonium fuel is relatively easy to convert into a nuclear weapon unlike most uranium fuel which nowadays is not weapons grade and so cannot be used to build a nuclear device.
So while there may be some efficiencies with recycling the fuel the security concerns, especially in this day and age, perhaps out weigh any benefit.
After some of the damage we have done in the last 15 years, I don't know if that's still the case.
It's not and I was in the US and saw the change firsthand myself since it affected me. I was an RA with a US university and worked part of the time at Fermilab. When I started there in the late 1990's the senior European postdocs who were on the experiment I was on were all looking for faculty positions in the US. 4 years later, after the 11/9 attacks, almost every European postdoc, myself included, was looking to get out of the US at the earliest possible opportunity. I don't know any who were planning to stay.